The manufacturing procedure of a 500 mm in diameter, f/2 hyperbolic primary mirror based on Computer-Controlled Polishing is introduced in detail. The mirror was finally polished to the shape accuracy of 13 nm rms and the surface roughness of 2 nm Ra. Testing methods and data analysis for different stages ranging from grinding to polishing are discussed. Some critical factors affecting the efficiency and accuracy of the grinding/polishing procedure are summarized. In addition, the preliminary work to make large off-axis asphere mirrors is presented. The difficulties in polishing and testing for both circular aperture and rectangular aperture mirrors are previewed, and a possible solution is given. To control the geometrical parameters such as radius of curvature and conic constant, a new profiler has been built, and it has proven very useful to improve the grinding efficiency. Finally, the manufacturing of small aspheres using deterministic grinding tool is also introduced. The fine grinding procedure of LOH's asphere grinding machine is presented.

We describe the silver coating of 1.3-m secondary nirror being used for infrared observations at Subaru Telescope. This was the first successful in-house runof silve coating on thelarge moern astronimical mirror. Silver was desposited over the chromium bondange layer, using a 1.6-m vacuum coating chamber at the Advanced technology Center of the National Astronomical Obervatoryof Japan in March 1998. The reflectnc eand scatter performnce are measured by micrScan at 670 nm and 1300 nm. Monitor over 17 month shows the silve coated mirror continues to maintain high refleciton.

In wide linear-field of view, large relative aperture mirror system, it is unavoidable to use high order aspheric surfaces. In this paper the design of the compensators for testing the secondary and the tertiary mirror of a 3 mirror system is described. The surfaces under testing have high order up to r¹⁶. The diameter of the secondary is 112 mm, radius of curvature is 211.462 mm, and the conic constant is 0.07744075. The diameter of the tertiary is 272 mm, radius of curvature is 197.722 mm, and the conic constant is 0.2623604. Three elements and four elements compensators have been designed. The residual aspherical aberration has been minimized to about λ/20.

Three-dimensional or x-y-z profilometer is a well-established method for measuring non-symmetric aspherical surface. In this paper, the design of three-dimensional, x-θ -z profilometer called dual gauge profilometer (DGP), which uses a granite straight edge with high precision linearity as reference to reduce the linearity error of ball slide, is presented. The benefits of using this reference structure, data processing and error surface reconstruction are also discussed. Through the use of the novel profilometer, a non- symmetric off-axis mirror with 600 millimeter in diameter can be measured with accuracy of 4 microns Peak to Valley (PV) within 40 minutes, including data processing time.

The increase of the primary mirror diameter for the modern telescopes brings to the necessity to search for the universal high-productive technology of optical mirror manufacture, that would allow loss of the optical quality. Such a technology has been developed by the authors. The main principle, taken as a basis, includes the fact, that the optical elements have a rigid light structure that is connected with the facial (operating) and rear plates in a non-detachable manner. The parameters of such a structure are chosen from the conditions to provide for the demands to the optical element rigidity, both in the exploitation and in the manufacture process as well. The optical elements (mirrors) produced by the given technology, surpass the known ones by their physical and mechanical characteristics, that allows to reach the ultimate optical characteristics, using in this case the traditional approaches and means for the optical surface processing. The given technology, in combination with bearing frame of the same construction and precision actuators (for example, magnetorheological ones), allows to create not only large mirrors but also segmented mirrors in large range of sizes.

Removal function models play an important role in the computer simulation and the practical Computer Controlled Optical Surfacing. This paper presents a novel general model, which can simulate the removal function of a grinding (polishing) tool with any configuration, as long as the tool runs in dual rotation mode. The removal functions of a dual rotation tool with a single pad or with two pads were calculated by this general model and by the existing single pad and two-pad removal function models, respectively and the simulation results coincide with each other. The grinding & polishing experiments also verify this general model. A set of optimized seven-pad flexible grinding (polishing) tool was developed according to this model. A template function model, which simplified the two-dimension parallel circles tracks programming problem into a one-dimension problem was derived from this model. A Φ300 mm, F5.9 focus lens, with 46 μm aspheric degree was successfully fabricated according to the programming results after 8 hours 43 minutes fine grinding & 15 hours polishing.

The advantages of common path interferometers for reducing effects of vibrations are well known. A scatterplate interferometer is one common-path interferometer that is well suited for the testing of large concave mirrors, however due to the common path characteristics it is difficult to perform phase-shifting. This paper describes a phase-shifting scatterplate interferometer where the phase-shifting is achieved by making use of the polarization characteristics of a birefringent scatterplate. The major advantage of this design is that it does not require any optical components to be placed near the surface under test. The theory of the interferometer is presented and experimental results are shown.

Complex optical system, especially the all-reflecting off-axis spherical system is developed and used in the remote sensing camera and the UVX lithophotography. The alignment becomes more important to such system. In this paper, a computer-aided alignment method is described. The wavefront errors are obtained by using the autocollimating interferometric test at some field of views. A serial of aberrations explained by the coefficients of Zernike polynomials is gotten. They are the object values and will be corrected. The least square method is used to determine the misalignments. This method is demonstrated by the results of numerical simulation. The practical experiments are also given.

A computer-aided alignment method is put forward in this paper. It combines laser shearing interferometry and computer- aided optimization, accurately measures the alignment of the optical elements of the system being aligned and gives the adjustment project to control the wavefront quality. The theoretical analysis and experiments demonstrate the ability and effectiveness of this computer-aided alignment method and it especially suits for the on-site alignment of large and complex optical system.

Cryogenic optical system undergoes wide temperature change; therefore it must be athermal. That means when the system is cooled down to very low temperature, its imaging property should be kept as good as at room temperature. One way to achieve athermal optical system requires that all optical and mechanical parts in the system be made from same material. An all-reflective cryogenic optical system was thus developed in IOECAS, in which aluminum alloy was utilized to make such a system. This paper describes the key techniques for manufacturing this cryogenic optical system: material selection, forging process of the aluminum alloy blanks, initial machining, heat treatments, and final figuring. The cryogenic test of the developed system proved the validity of the manufacturing process.

The control system of adaptive optic of a large astronomical segmentated telescope was designed and tested. The dynamic model and the amplitude-frequency analysis of the new magnetic rheology (MR) drive are presented. The loop controlled drive consists of hydrostatic carrier, MR hydraulic loop controlling system, elastic thin wall seal, stainless seal which are united in a single three coordinate manipulator. This combination ensures short positioning error δφ⪅50 nm and small time of response. The main feature of a large astronomical telescope (diameter 25 m) is the large number (in our case 512) of primary mirror segments usage, which are united in one reflecting system. This design makes easier the problem of the primary mirror manufacturing but brings another problem to ensure precise movement of every mirror segment movement and to provides a perfect coincidence of the mirror segments constantly. Suggested parameters of the drive, based on magnetic rheology (MR) liquid are: precision δφ⪅50 nm, time of response T≤0.2 s. Error of positioning of loop-controlled MR drive may be expressed: δφ = δ_r + δ_db + δ_f + δ_i, where δ_r -- 'reproduction' error (depends on drive structure and controlling system, and in our case the drive ensures δ_r = 0); δ_db -- 'disturbance' error (δ_db = 5...10 nm); δ_f -- error, because of static friction forces action (δ_f equals k_t x F_st = 2 x I_s/k_i = 30 nm, where k_t -- transformation coefficient of the drive; F_st -- static force in the drive; I_s -- 'starting' current in the drive; k_i -- transformation coefficient of the measuring system); δ_i -- 'instrumental' error. In case of a laser interferometer usage δ_i = 10 nm and the summarized error is δφ≤50 nm. Time of response T of the drive depends mainly on the combination of time constants of the next elements: MR-valve T_m, elastic elements (pipes, thin-wall tubes, bellows) T_el, moved object (mirror segments) T_s. Experiments show what the MR drive ensures: T_m = 20 ms, T_cl = 20 ms, T_s = 100 ms. Analysis of the amplitude-frequency graphs shows, that the MR-drive ensures summarized time of response till T≤110 ms.

Balloon-borne Solar Telescope is an optical telescope with effective aperture of 80 cm. To reduce polarization effect to measuring of solar magnetic field, the optical system is specially designed and the collimating lens is special and difficult to calibrate. To reduce the gross weight of telescope, the primary mirror is lightweight with thickness- to-diameter ratio of 1/10. But the system must reach to its imaging quality of diffraction limit. So some special techniques are introduced to guarantee the optical imaging quality. First, lateral shearing interferometer is used to test every optical component after they are assembled in barrels or cells; then two visible points that can be seen through alignment telescope form the optical axis of every component. After system optical axis is established also by alignment telescope, those optical components can be calibrated precisely on it. Since lacking standard mirror that is the same size as primary mirror, some ground-base trial observations without vacuum tube were taken to test the imaging quality. According to astronomer's conclusion, the system can get high resolution solar image when in operation.

A kind of super larger, aperture combined, reflective plane wavefront is recommended in this paper. Structure principle and the method of forming accurate plane wavefront are described. Accuracy is analyzed, and several results of local experiments for arguments are discussed. All these prove that the SLAPW with accuracy higher than λ/20(λ-wavelength) can be constructed, which will be used in testing astronomic instruments with any super large aperture.

The development of a lightweight space optics remote sensor with wide field and high resolution is one of the key projects of the researchers. As the traditional approaches couldn't meet the requirements of the project, some modern strategies and methods should be adopted. A high precision, long shaped meniscus mirror is studied in this paper, and its material selection, shape, lightweight strategies, machining method, multi-point support pattern and structure are described. Fused silica or Zerodur is selected as material of the mirror in connection with specific stiffness, dimension stability, machining and cost. An aspherical long shaped meniscus mirror is designed for the optical system. There are rarities of lightweight patterns, i.e. triangular, rectangular, circular and hexagon, and the open hexagon (honeycomb) lightweight pattern is selected with regard to the mechanical and thermal property of the mirror. The mirror should be supported at the edge. With the computer simulation, 6-point flexural support pattern is employed, and the conflict problem between multi- point constraint and freeing the degrees of freedom (DOF) is solved. While the mirror is under the loads (0 gravity at different directions, temperature level exchanging and specified temperature gradient, etc.), the deformation of its surface profile is also acceptable. Finally, the machining method of the mirror is introduced and the allowable assembly error of the mirror set is presented.

The surface of K9 glass substrate whose size is 220x220x40mm³ is polished by bowl-feed polish with polishing agent of ultra pure water combined with cerium dioxide (CeO₂). The super smooth surface with standard rms surface roughness less than 1 nm and reflective wavefront 0.127 λ(p-v) (λ=632.8 nm) was got. The high reflective thin film, whose reflectivity measured by Lambda 19 photometer is more than 99.5% at wavelength 1054 nm for incidence angle 0°, and whose laser induced damage threshold is 26 J/cm² (1054 nm, 1 ns), was coated on this super smooth surface of K9 glass substrate by electronic beam evaporation deposition in the APS1504 coating machine. After alternately coating hafnia (HfO₂) and silicon dioxide (SiO₂) multilayer on the K9 glass substrate surface, this mirror's reflective wavefront is 0.17 λ(p-v) (λ=632.8 nm). The high quality cavity mirror was got.

This paper introduces our research on design and manufacture of space remote sensor's big lightened scan mirrors in brief. And we also look forward to the development.

In the investigation of Inertial Confinement Fusion (ICF), the high power laser beam must be focused on the target (focus plane) given. In the ICF indirect drivers, the target fixed in a cavity is cylinderal, there are the Deuterium and the Tritium in the target, the experiment result relatives with the temperature radiated in the cavity, and the temperature relatives with the laser energy power incided. Thus, it is key that there must be enough of energy incided, and the energy runs out barely. So, to increase the laser energy incided, the focus spot should be very small. Base on the design of focus optical systems of the SHENGUANG serial facilities and the theory analyses, as the diffraction of the light, the laser beam passing through the optical systems gets a spot on the focus plane. In order to reduce the edge of the main spot or the focus spot size, we advance a method of dividing aperture of the focusing optical system, the diffraction theory of light shows that the diffraction main spot is reduced, it indicates that the method of dividing the aperture may be recommended.

The largest astronomical telescope in China with 2 (DOT) 16 m aperture had been installed in 1989 at Xinglong station of Beijing Astronomical Observatory (BAO). From observations of many years including international cooperation programs, a lot of valuable astronomical data and some influential achievement had been obtained. This equipment had been appraised in December 1996. The optics of the telescope has some distinctive features. It has the Ritchey-Chretien Cassegrain system of focal ratiof/9, and the Coud'e system of focal ratiof/45. In this paper, the principle and procedure of alignment of Cassegrain and Coud'e optical systems are described. In the process of adjusting we used two sets of micro-alignment telescope (MAT) and its accessories, designed and manufactured an especially cube prism and its mechanical device. We also used a telescope tube of a 6' theodolite and some adjustable reticles to finish the alignment. With a star as the light source, Foucault's knife-edge test photograph of the optical system at the Cassegrain focus is given. After assembling the fused quartz field corrector on Cassegrain focus, a star cluster photograph, with a whole field of view (30 X 30 cm) also performed. Finally, in the whole field of view from center to edge and corner, the images are round. A member of the appraisement committee measured the linear size. The diameters of dim stars are 0 (DOT) 18 - 0 (DOT) 20 mm. These show that the alignment of the optical system, the design of the fused quartz field corrector, the select of the fused quartz material and its fabricate method are successful.

An ellipsoid mirror with Φ500 mm aperture has been successfully manufactured by NAIRC. The parameters of the mirror are as follows: diameter is Φ500 mm, radius of curvature is 1996 mm, conic constant k=-0.9545, requirements of surface accuracy are λ/10 (P-V) and λ/40 (RMS), (λ=632.8 nm). Based on the surface type, three kinds of test optics are designed. The errors of the elements in the testing optical path are analyzed. The small tools are used to figure the asphericity of the mirror. Finally surface accuracy of λ/10 (P-V) and λ/50 (RMS) are reached.

In this paper, according to the structural features of large reflecting mirror positioning system and the fitting requirement and professional standard of 'Matched Fit,' we explained in detail for the design principle if machining tolerance of the reflecting mirror fitting hole and positioning central shaft. The design procedure and computing method of the tolerance and the technological design process and the guaranteeing measurement when the 'Matched Fit' mode of production is adopted.

The potassium dihydrogen phosphate (KDP) crystal elements served as switcher and frequency converter are the key components in large laser system for inertial confinement fusion (ICF). Such kinds of crystal components, which can be treated as thin plates, are usually fixed on a vacuum chucker connected to the worktable and fabricated by the single point diamond turning machine. The bend due to the vacuum chucking is one of the most important contributors aggravating the distortion of the crystal plate. In this paper, we analyze the influence of vacuum chucking on the distortion of the crystal plate by using finite element analysis method. The calculating results show that the parameters of the chucker, such as the size of the chucking hole, the distribution of the holes, the vacuum pressure and the status of holding the crystal plate, are closely related to the distortion. Another interesting result is that the chucking force from the holes would have effect on the waviness of the surface.

Varied line-space (VLS) plane grating is the great achievement in the history of gratings. But its fabrication is so difficult that only few countries can make it with a grating ruling engine. This paper firstly studies the focusing property of the VLS plane grating. Then a VLS plane grating is designed. The ray-tracing result shows that the grating has a good self-convergence feature. A VLS grating sample was ruled using the improved equi-space, intermittent grating ruling engine in Changchun Institute of Optics and Fine Mechanics (CIOM). The groove spacings of the grating sample were measured by using Talystep. The results show that the groove spacing is varied continuously, which gives the conclusion that the design method and the VLS control method in this paper are effective.

Numerical simulation of temporal evolution and spatial distribution of directors in a liquid crystal (LC) microlens is presented. We show that splay deformation and twist deformation obtained for the LC microlenses with a pre-tilt angle and without one are quite different. Details of director orientation in both types of LC microlenses are discussed.

It is known that for the converged laser beam, the axial intensity distribution corresponds to a Gaussian curve, that is, the intensity on the focal plane is the peak intensity. When it defocuses, the intensity would decrease rapidly. In some cases, optical data storage, for instance, we expect the intensity within a certain distance to be almost equal. In this paper, we propose to use a pure phase superresolution apodizer to optimize the axial intensity distribution of the converged laser beam and at the same time attain superresolution. The intensity point spread function remains almost identical within certain region and the depth of focus is extended.

Composite recording material was synthesized by hydrolysis and polycondensation of tetraethoxyorthosilicate and silane with photoinitiator added. With infrared spectral, the mechanism of response to light of the material was investigated. Vibrational spectroscopy is used to provide insight into the structure changes that occur when films are exposed with UV light. The decrease of absorption intensity in v(C = O) 1698 cm^-1 and v(C = C) 1636 cm^-1 bands reveal the polymerization in material after irradiation. Comparative experiments between two systems with mixed initiation and sole initiation are exported. UV spectra show that the transmittance of the sol-gel thin films drops down in a wavelength range of UV with addition of photoinitiator and irradiation. Developed in dilute base solution, micro-optical elements, such as gratings, were fabricated by contact copy with UV-exposure.

To realize a well defined binary grating (for grating originals as well as grating masks), it is helpful to use a rectangular resist profile because of the importance of the fill factor. This can be achieved easier by e-beam writing than by holography. On the opposite, well-known handicaps of e-beam writing are large writing times and grating ghosts (caused e.g. by stitching errors). We fabricated chromium grating masks (period 500 nm, size 100 mm x 100 mm) by an extremely fast and specialized e-beam direct writing process. The typical and critical parameters, like fill factor and wave front, were locally measured in the whole grating area. The paper will show the method of e-beam writing and the results of lateral grating quality. The remaining errors are separated in problems caused by the writing process and in problems related to resist technology and etching process.

The high frequency compensation of the array micro-optical elements (MOE) is presented in this paper. The authors analyzed the spatial frequency loss of the profiles of the elements by Fourier series at first, and give the compensation scheme in the mask moving (M2) project exposing system. The blazed grating is discussed as an example with the smart mask design and element fabrication. As a result, the transitions of the 5 micrometer blazed gratings were cut down from 1.58 μm to 1.29 μm.

Optical subwavelength gratings are of growing interest for the realization of special optical effects such as artificial birefringence or antireflection layers, for example. The optical properties of such elements strongly depend on the accuracy of the fabrication technology and tools. Although e- beam lithography is known to be a high-accuracy fabrication method, even with this technology systematic grating errors may occur which affect the optical function. One example is the existence of grating ghosts (i.e. undesired propagating diffraction orders) which may occur even in the case of subwavelength grating periods. In this paper we describe how this effect is related to the address grid of the e-beam writer. Measurements of the diffraction spectrum of subwavelength gratings indicate the importance of this effect. The adaptation of grating period and address grid allows the fabrication of ghost-free subwavelength gratings.

We designed and fabricated a diffractive optical element (DOE) applied to improve the characteristics of the divergent angles of the high power infrared semiconductor laser. The fabrication of the DOE and the test of the infrared illuminating system integrated with the DOE are studied in this paper. In order to reduce the difficulty of the micro- fabrication, we proposed a method of quantizing the continuous profile partly with different level while the DOE was designed. The diffraction efficiency of the DOE and the ellipticity of the illuminating system were tested and the results of the experiment illustrated that the DOE with variable-level step phase achieved the design requirement very well.

An interesting scope in micro optics is the transformation of an arbitrary incoming wave front into another arbitrary intensity distribution. This task includes simple focusing as well as the sophisticated control of the propagation properties of the illumination wave. For the reasons of wave length independence and high efficiency, it is necessary to use refractive elements. The design of these beam shaping elements is made by well-known numerical methods based on wave optics. One technology for the fabrication of refractive micro optical elements is gray tone lithography which is capable of the realization of continuous surface profiles with a total height of up to 65 μm. With the use of gray tone lithography on a preform, even higher profiles are capable of being produced. We fabricated high quality lens arrays and different beam shaping elements. The generation of top-hat intensity distributions with different (non separable) shapes or a line of constant intensity are examples of application. We used a single mode fiber as well as a laser diode and a multi mode fiber as light sources. The illumination waves are Gaussian or Gaussian-like beams.

Performances of diffractive and refractive microlens array have been studied and compared. Besides the diffractive microlens array which can be fabricated by means of the microfabrication technologies, method for manufacturing continuous profile refractive microlens array with larger sag depth has been developed for solving the unique problems like diode laser alignment. Both diffractive and refractive microlens array with different numerical aperture and other parameters are fabricated according to the application requirements, experimental results are given.

A uniform period fiber Bragg grating can be chirped by applying an axially strain gradient. We have demonstrated a novel technique for making the chirped fiber Bragg gratings (CFBG), which involves bonding an unchirped fiber grating to the surface of a tapered stainless steel plate which is strained by loading. Three kinds of tapered profiles (convex, gradient and concave) of plates and two kinds of loading procedures (bending and dilating) were used as the means of an in situ absolute center wavelength shifting and reflection bandwidth broadening of a CFBG. By this method, the center wavelength of a CFBG could be tuned from 1548.92 nm to 1550.99 nm, and a maximum adjustable chirp bandwidth of 2.00 nm was obtained for a fiber Bragg grating in 50 mm length. An application in the accelerometer was introduced.

The transmission characteristics of phase-shifted long-period gratings (LPGs) are simulated theoretically by a combination of coupled-mode theory and fundamental-matrix method. It is suggested that a phase-shifted LPG device cascaded with another normal LPG can be used to flatten the gain spectrum of an erbium-doped fiber amplifier (EDFA) with all three gain peaks. The results of simulations have shown that a broadband amplifier with peak-to-peak 0.7 dB gain variation over 36 nm can be practically realized. It proves that such a gain- flattening fiber filter is indeed plausible, and has a potential application in gain-flattening in dense wavelength- division multiplexed (DWDM) telecommunication systems.

In this paper, the process of fabrication of binary optical elements by thin film deposition has been introduced. An eight-level phase microlens array has been fabricated with 20 X 20 rectangularly shaped microlenses, focal length of 100 mm and lens size of 0.8 mm for the wavelength of 0.6328 μm. Our measurements show that all the step heights are nearly identical and the controlled precision of step heights was better than 1 nm.

In this paper we give a brief review of the fundamental acousto-optic interaction theory. Design and fabrication considerations for Multichannel Bragg Cell are studied. We designed and fabricated a four-channel LN/ZF-6 modulator which has 75 MHz center frequency, 15 MHz bandwidth and more than 10% diffraction efficiency.

Concave gratings are now being widely developed for applications of spectrometers, imaging spectrometers and homochrometers. But for the holographic manufacture of concave gratings, it's hard to design the recording parameters because of the nonlinear equations set. We have developed an interactive program, which can be used to auto-design the position parameters of the two recording spherical wave, and evaluate the results by using a ray-trace procedure. The performance is satisfactory.

The principle, method and technical characteristics of high- precision centering and undeformed cementing technique for optical lens are presented in the paper. The method has been used in achromatic lens of 5X and 10X projection photolithographic objective in IOECAS'. The decentration error is within 1" and surface accuracy maintains in original ± λ/20 approximately ± λ/40. The method has the advantages of high precision, fast speed and undeformation.

In this paper, we have discussed the development trend of modern ultra-precision machining technology, described the new structural and control technologies recently used, especially the characteristics of Linear Motors and their applications in ultra-precision machining system. We have also presented our own conception on the future development of ultra-precision machining technology.

The requirements to the design of the optical components, the surfaces of which are machined by diamond turning, are systematized. It is demonstrated that the requirements to the design are determined by the type and parameters of the machine on which processing is realized as well as by the optical component application taking into consideration the possibilities of the technology control of component geometry and optic parameters and the technology of the assembling of the whole device. The examples of the design of the low cooled off-axis, W shaped, scanning and other types of optical components. There are presented design of the some components that may be manufactured only by means of diamond turning (polygon mirrors with different tilt angles, mirrors with concentric and shifted optical surfaces). Recommendations and design solutions that are suggested may be used for the designers of the optical devices.

A quantitative expression for mid-spatial frequency error of the large planar mirror fabricated by computer controlled polishing is employed in terms of wavefront's power spectral density (PSD). The PSD information is calculated from wavefront measured by large phase shifted interferometer. The optimized process parameters are investigated to reduce the mid-spatial frequency error with adequate efficiency to meet the conventional requirements such as P-V and RMS wavefront errors. Based on the criteria of efficiency and PSD, the optimized parameters have been obtained for fabricating precision planar mirror. As an application, a 270 mm x 270 mm x 30 mm mirror has been finished after 10 polishing hours. The P-V value of the reflective wavefront is 0.19 λ (λ= 0.6328μm), and the PSD distribution has also met the requirements.

Though Optical lens with free-form lens (FFL) can be significantly used in optical rectification, it is very difficult to manufacture it. Computer-controlled optical surfacing technology is used to fabricate it efficiently. In the stage of figuring FFL, the component is fixed with vacuum flat sucking disk, then ground by the progressive mode while the abrasion wheel is trimmed on-line. A lapping and polishing tool that conforms to the shape of FFL is used to finish the optical mirror. Because FFL has no any constraints, general interferogram technique can not be applied to its measurement and the accuracy of three-coordinate measuring machine is too low. So a high-precision measurement method based on image conversion is developed to measure the surface. Generally speaking, the precision after forming is under tens of micron. Then the error correction technology is employed to improve surface precision. Getting input controlled variables from error dot matrix involves deconvolution. Least-square filtration is used to solve deconvolution and wavelet analysis is used to filter fringe and tip. Then the surface after error correction is measured again. So a closed loop is formed. The accuracy of optical mirror in our experiment is under 4 micrometers while Ra is under 5 nm.

To test the small aspherical mold surface with large NA, we develop a kind of null lens system which is made up of four thin lenses, the first two thin lenses form a system with small NA which is mainly used to produce positive spherical aberration; the other two thin lens form a large NA system which offers negative spherical aberration; the latter together with that of the front two elements meets the null testing need. The wavefront variation of testing system due to the manufacture & test & assembly and adjustments error is analyzed, by this analyses, we know that we are capable of measuring the aspherical surface to the accuracy of 0.05λ, it is enough to satisfy the testing of mold surface of compact disc object lenses.

People usually take the machining of elements with super- smooth surfaces just as a polishing process. But occasionally super-smooth polishing cannot be accomplished even conducted under a succeeded polishing procedure, resulting in the failure of obtaining super-smooth surfaces repeatedly. A concept of super-smooth surfaces machining 'process technology' is proposed which takes super-smooth surfaces machining as a system in general, not merely a polishing process. We take the machining of super-smooth surfaces as a chain consisted of some key nodes. The failure at any node will result in the failure of the final surfaces. The nodes in the process technology system refer to a series of key sub- items, such as sample material selection, pre-machining, and super-smooth surface evaluation, et al. With the aid of polishing experiments, the effects of some key sub-items are discussed.

In this paper, based on the indentation under different loads, the influence factors for brittle-ductile transition of optical glasses has been investigated theoretically through the simulation of a single grain grinding with the diamond indenter. By the surface and fracture features, the grinding rules and the critical load conditions for the brittle-ductile transition of different optical glasses, the critical grinding depth of the single grain and its influence factors are obtained for the brittle-ductile transition in ultra-precision grinding process. The experimental results show that brittle- ductile transition of optical glasses is controlled by cutting depth of a single grain. When the cutting depth is less than the critical depth, optical glasses are ground in ductile mode. When mean grain size is less than 20 μm, ductile mode grinding of optical glasses can be realized with the relatively larger tangential speed and smaller feed. Otherwise, lubricants is the important factor influence critical cutting depth. Finally, the experimental results of BK7 and FCD1 optical glasses grinding are given.

According to Preston equation, mathematics model of magnetorheological finishing (MRF) is established in this paper. We analyze the pressure acting on workpiece of this model, and find out that the pressure consists of hydrodynamic pressure and magnetization pressure. At same time, the magnetic field used in magnetorheological finishing is introduced, and the expression of intensity of this magnetic field is given. A MRF example for convex spherical surface workpiece in this magnetic field is presented, the mathematical expression of the pressure is deduced, and the rationality of the mathematical expression of the pressure and the reliability of the mathematics model is verified by experiment. Based on mathematics model of magnetorheological finishing and experiment, the curves and the laws of the effect on magnetorheological finishing by several parameters are given.

In order to ensure surface shape accuracy of ground optical parts produced by locus forming, factors of precision grinding machine that affects surface shape accuracy of the part are theoretically analyzed. Formulas used to calculate the error that can be canceled through the machine fine-adjusting device are deduced. Using calculated error values to adjust the fine- adjusting device is able to reduce the surface shape error, and then surface shape accuracy of parts is ensured.

This paper combines nonabrasive polishing with cryogenic polishing and proposes a new method to get super-smooth surface with angstrom dimension -- cryogenic polishing without abrasive. We describe its process and give some experiments to show how to keep stabilization in polishing and how to reduce effects of water quality of ice disk on surface roughness. Experiment results show that modifying ice disk before polishing for eliminating vibration and water quality of ice disk have a vital effect on surface roughness. Experiments of polishing K9(Chinese type) glass with ice disk of tape water, pure water and de-ionized water show that workpiece surface roughness polished by ice disk of de-ionized water is the lowest, up to about Ra 0.5 nanometer (nm). This is a new process to gain super-smooth surface with angstrom level on optical material.

In this paper, the authors present a new technique which through electrolytic truing, could use metal bonded supermicro diamond wheel to machine optical glasses and obtain optical surfaces with best-quality finish. Using this technique to machine K9, F4 and zerodur, the surface roughness Ra could reach a value less than 10 nanometer and a planeness less than 1 μm. In addition, the authors have also studied some phenomena occurred in the grinding process.

Sagittal focusing double-crystal monochromator, which has the double functions that are dynamically monochromating synchrotron light and focusing the monochromatic light, is the kernel instrument of hard x-ray beam line in synchrotron radiation, and sagittal focusing crystal is the key part in the monochromator. The sagittal focusing monochromator, which is being manufactured, has energy range, 5 to approximately 20 KeV, focusing radius, 0.8 to approximately 5 m, focusing precision ΔR/R, better than 0.75%, and at 10 KeV, meridional anticlastic deformation, less than 1.8 arcsec, sagittal focusing slope error, less than or equal to 2 arcsec. This paper discusses the design, manufacturing and testing about the sagittal focusing crystal in the sagittal focusing monochromator.

The newest achievement of super smooth processing technology of optical element bowl-feed polishing (BFP) is described. The need background and developing tendency of super-smooth optical elements are analyzed. The key problems of BFP have been found, the process parameters have been determined, and the basic method of BFP has been worked out by the study of process factors and processing principle. Φ50 mm k9 glass sample with 0.5 nm surface roughness and better than λ/8 surface shape has been processed.

ELID (Electrolytic In-process Dressing) grinding is a new ultra-precision machining technique which employs in-process electrolysis to dress the metal bond diamond wheel in grinding process. In this paper, the principle of ELID grinding is introduced. An optical glass sample is ground by using cast iron bond diamond wheel and ELID technique. Tested by WYKO RST Plus, the grinding surface roughness Ra is 2.48 nm. A conclusion can be drawn that using ELID technique can realize the ultra-precision grinding of optical glass.

Experiment methods such as X-ray diffraction, ICP-AES, TEM are adopted to study the relationship between optical properties and inside defects of CVDZnS samples which deposit at different experiment conditions. Through our studies, we draw the conclusion that there inside the material exists a kind of Zn-H associated particle which functioned as optical scatter centers. These scatter centers will lower the transmittance of CVDZnS both in the visible and the IR spectral regions. However, these Zn-H associated particles can be diminished through Hot Isostatic Pressing processing, and after the processing the transmittance of ZnS will substantially improved, especially in the visible spectral region.

Based on the anisotropy of granular structure, the reasonable criterion was given to understand the generation of the prior cleavage or slip for each cleavage system or slip system. The phenomenon that the roughness of the diamond turned single crystal materials's surface distributes in scallop is explained, and a turning method is presented to eliminate the scallop distribution. Beside this, the AFM was used to observe the micro-topography of the light and shade area of brittle single crystal material's diamond turned surface. The criterion is in good agreement with the observed results.

A scheme of tunable optical orthogonal encoder/decoder for all optical code division multiple access communication is proposed in this paper. It consists of a fiber splitter, a fiber combiner, N of 2 x 2 electro-optic switches and N of optical delay lines. It overcomes the poor correlation, small capacities and narrow tunable range of prime-code and 2ⁿ code tunable optical encoder/decoder found in the literature. The configuration of the proposed tunable encoder/decoder is simple and it is flexible for application. In addition, it has low optical power loss and easy in practical uses.

In this paper a practical optical CDMA (Code-Division Multiplexing Access) encoder/decoder based on optical fiber delay lines (OFDL) for OOCs (optical orthogonal codes) is proposed, its performance is analyzed in three aspects, (1) The probability of bit error versus chip pulse width, (2) Stability versus temperature, pressure and strain, (3) The relationship between length error and bit error rate in NRZ format and RZ format.

Based on the theory of near-field optics, the principle of light transmission of optical fiber microprobe is analyzed and the theoretical data of the topography of ideal optical fiber microprobe are presented. All kinds of factors influencing probe topography are also discussed. Grounded on repeated tests, a fabrication approach of the tip of optical fiber microprobe, which is of simpleness, good repetition and easy fabrication, is formed. A method for plating Au film is developed to fulfill the requirements of high light reflectivity, chemical stability and conductivity. The result observed by SEM shows that the Au film is uniform and continuous. The good performance of light transmission of the plating-Au-film optical fiber microprobe is proved by light transmission tests.

This paper introduces the functions of collimation and beam shaping of LD can be integrated within a single micro-optical element -- GRIN lens. A symmetric and collimated laser beam can be achieved when the GRIN lens with two different focal lengths is positioned correctly. The design, the fabrication of the GRIN lens are demonstrated respectively. The effect of elliptic mask apertures on the parameters of GRIN lens is analyzed.

This paper studies the effect of abrasives size on machined workpiece surface in solid abrasives lapping. From the results it can be seen that the value of roughness of the machined workpiece surface increases as the size of abrasives increases. Its principle is same as ultraprecision grinding and tradition lapping. But for same size abrasives, the results got in this paper is better than them in ultraprecision grinding and tradition lapping. In this paper, the roughness of machined workpiece surface can reach Ra2.83 nm, by using the abrasives which size is 3.5μm.

Some important progresses in Chinese optical manufacturing technology in the 20th century were reviewed in three development stages. Then the present situations of Chinese optical manufacturing of binocular and camera were shown. At last, six main trends of manufacturing technology of optical elements in the early 21st century were given, considering the national conditions.

Direct bonding without the use of adhesives was demonstrated on Ti:sapphire laser crystals with a bonding surface of 12 mm x 6 mm and the bonded region was evaluated from the macroscopic to the atomic level by three different methods. Wavefront distortion caused by the bonded region of 10 mm x 5 mm was estimated at 0.031 wavelengths (λ) at 633 nm. Micro defect measurements by a laser tomography method showed that the number of micro defects on the bonded region were much smaller than that of the intrinsic ones inside the crystal. From a magnified inspection, atoms in the bonded region were well arranged with the same regularity as inside the crystal. In addition, micro defects 1 nm in size appeared slightly along the bonded interface where the titanium ion concentration was four times higher than other parts of the crystal.

Three interferometric methods for testing the large concave spherical mirrors with long radius of curvature, the large convex spherical and flat surfaces and the large aspherical mirrors are described respectively. A number of testing results obtained with each form of interferometer are presented.

In absolute interferometric flatness testing, various flats are measured in multiple configurations to approximately solve for the surface figure of each flat independent of the reference flat used. This measurement sequence generally involves rotation of one flat as well as removal and replacement with different flats. The deviation between the rotation center of the flat and the coordinate center of the software system used causes measurement errors, as do any errors in replacement location and general error sources associated with interferometry. In this paper techniques are described to optimize the accuracy of the three-flat absolute flat testing technique, and the various sources of measurement error are analyzed. Use of crosshairs for positioning and rotation adjustment as well as general methods to improve interferometric testing are described. Results from the high- accuracy absolute flat testing are compared with standard absolute flat results to evaluate how to achieve improved measurement results.

Lateral shearing interference has such unique merits in optical testing, (1) anti-shock, (2) reference spherical surface is unnecessary. (3) the ratio of intensity of two beams is 1:1 in any case, (but in ordinary interference, the ratio of intensity of two beams isn't always 1:1 in any cases, because its ratio can be change according to different testing condition, in some cases maybe it is 1:25, so the interferogram is vague). But its interferogram is different from ordinary interferogram for same tested wavefront (so the experience for testing ordinary interference isn't applied to shearing interference completely). That is to say, the position and the amount of the error wavefront can't be taken clear, even if for the same tested wavefront, the shearing interferograms aren't same completely, when using different shearing distance. The quantitative process just solves this problem through two shearing interferograms whose shearing directions are normal to each other so the real error condition of tested wavefront can be calculated. The calculation can use two different ways, that is: Transposition Zernike Coefficients Method and Extended Simultaneous Equations Method. At last showing 2 types shearing prisms. We can use it to get two shearing interferograms at the same time and to change the shearing distance arbitrarily.

Using interferometer to test an optical component with super- long radius will face two very difficult problems: how to measure the radius precisely and how to avoid air disturbance and vibration, especially for a convex surface. In order to solve these problems we design a cement doublet, which is combination of plano-convex and plano-concave lenses, as a compensator to generate super-long focal length. This cement doublet looks like a plane plate, but has very little optical power. Two cemented lenses are made of different optical glasses with very small differential of refraction index. This Compensator is inserted between the interferometer and the optical component to be tested. Advantages of above design are the distance between the interferometer and tested component can be shortened to a desired value and air disturbance and vibration can be reduced to an acceptable level. Only thing you should do is to control the refraction index difference tightly.

The power spectral density (PSD) was employed to be the specific criterion of the large aperture optical components. Its definition and calculation has analyzed in detail, and the results were given consequently. Furthermore, the calculation of the averaged PSD in different situation is discussed.

In modern semiconductor and optics industries, there is a strong demand for a highly sensitive and non-contact surface profilometer. This paper describes an optical heterodyne surface profiling interferometer for on-line non-contact measurement with automatic focusing which has been developed recently. The essential feature of the profilometer is a newly designed common-path configuration to minimizes the effects caused by vibration, air turbulence and other environmental variations. A single-mode frequency-stabilized laser diode (780 nm) serves as the light source to make the whole system compact (total volume 250L x 200W x 100Dmm). A powerful signal processing scheme is also developed, which includes three parts: automatic voltage control, phase measurement and automatic focusing control. All these make the repeatability and stability of the profiling interferometer greatly improved. The system has vertical resolution of 0.39 nm and lateral resolution of 0.73 micrometer. During approximate an hour, the stability is within 1.95 nm (3σ).

A description is given of a refractometer on which refractive indices of solid materials have been measured from 0.4 micrometer to 12 micrometer. The computer controls the procedure of measurement and automatic measuring is achieved. Infrared light, visual light and grating monochromatic provide the system with continual monochromatic wave. Different detector and different method of measurement are used at different range of wavelengths. Oscillating slit technique is used to improve measuring accuracy. Refractive index values are obtained with an estimate uncertainty of 5 x 10^-6 in visual waveband and 2 x 10^-4 in infrared waveband. Values of refractive indices for germanium are given in the end.

Far-ultraviolet IMaging Spectrograph (FIMS) is a far ultraviolet diffuse imaging spectrometer which will be launched in 2002 as the main payload of KAISTSAT-4. We have designed the optics for observing diffuse emission sources by employing an off-axis parabolic cylinder mirror in front of a slit which guides lights to a diffraction grating. The reflective diffraction grating is an ellipse of rotation providing angular resolution. We describe our plan to measure the off-axis parabolic mirror and our initial experiments to establish the measurement technique. To assist manufacture of the off-axis parabolic cylinder, a cylindrical wavefront generated using computer generated hologram (CGH) will be used during the polishing to check errors in surface profile using the Fizeau interferometer.

A measuring method of residual stress distribution in xenon flashlamp tube is described in this paper. The stress birefringence of both front surface and back surface of the xenon flashlamp tube could be obtained quantitatively. In our experiments, the smallest measuring optical path difference is 0.2 nm. The resolution power of optical path difference of our system could be 0.01 nm. Preliminary measuring results indicate that this system could justify the measuring precision requirement of stress birefringence of xenon flashlamp tube. Because of the simple operation of this measuring system, this system is convenient to be automated at little cost of precision, which is a very important merit when there are mass measurements to do.

The vectorial shearing interferometer is based on the Mach- Zehnder configuration, by incorporating the displacement shearing system, composed of a pair of wedge prisms that modify the optical path difference and the tilt of the sheared wave front with respect to that of the reference wave front. The variable shear and tilt may be implemented along any direction, by choosing the displacements Δx and Δy. The number of fringes and their orientation may be controlled with the shear direction and its magnitude. The shearing direction may be chosen along an arbitrary direction. A gradient of the phase function is obtained in any direction with the knowledge of the prescribed displacement in the x- and y-directions.

A pixel-level image fusion scheme based on Laplacian pyramid decomposition is presented. The basic idea is to perform a Laplacian pyramid decomposition of each source image first, then the Laplacian pyramid of the fused image is constructed using region-based weighted operators according to different fusion rules, finally the fused image is obtained by taking inverse pyramid transform. Both visual quality (regarded as contrast and presence of fine details) and absence of impairments or artifacts are concerned in our method. This approach has been successfully used in image fusion. The experimental results show that the fusion scheme is effectual and the fused images are more suitable for human visual or machine perception.

A Digitalization measurement method of large radius of curvature is presented in this paper. Non-contact Newton's rings are formed by an interferometer. The interferogram is imaged in CCD array. The scale of image pixels corresponding to Newton's rings that related to the radius of curvature is obtained by scanning fringes or other optical methods. The radius of curvature of spherical surface detected that can be both convex and concave is up to 25 Meter. The accuracy of measurement is better than 0.3 percent.

In this paper, we introduce and discuss in details the laser damage test facility and threshold measurement program of optics. The test facility with different nanosecond pulses at maximum 20 Hz can perform all the usual damage tests: 1-on-1, N-on-1, S-on-1, R-on-1, and the raster scanning method. The test damage facility has ability for measuring the damage threshold of the small and large scale optics. The 1-on-1 and the functional damage threshold are discussed, and know that the functional damage may be better to apply for HR coatings.

An adaptive phase-shifting interferometry, insensitive to the disturbance of constant term of phase perturbations induced by environmental vibration and air turbulence is introduced. Where high frequency intensity modulation of laser beam and phase lock-in as well as the closed loop control techniques are used. The wobble of interference fringes can be compensated, and sequentially be locked at arbitrarily chosen phases for phase-shifting testing. Comparing with other similar techniques, here the depth of signal modulation is not limited by the magnitude of optical path difference (OPD) and the fringe contrast is not reduced by the modulation, hence a high SNR can be obtained. The experimental results and conclusions are presented.

One of principle difficulties in zonal wavefront reconstruction is computationally intensive. In this paper the method of wavelet decomposition is applied to the reconstruction matrix, then a threshold is added to the wavelet-coefficients matrix to remove the high resolution wavelet coefficients which can be ignored. The resulting matrix is sparse, leading the computational cost decreases greatly, so the computational speed increases. Theoretical analysis and computer simulation are made and expected result is got.

Based on introducing the principle and method of processing technique for interference pattern with step using the characteristic of phase-shift interferometry. The paper has discussed a new phase-unwrapping algorithm for the phase map containing discontinuities. The correct phase values in the presence of discontinuities, especially those caused by the object with height steps, can be obtained. This algorithm is fast and accurate. The results of the measurement of three- dimensional object with height steps are presented. These techniques have been successfully applied to measure the surface and wave aberration of the system with step.

Among the theories of scatter plate interferometer, the method based on statistical optics is most successful. This method is developed in this paper. The method of equivalent field based on fractional Fourier transform and the method of statistical average based on statistical optics are used. The relations between the interference fringes and the wave aberration of the tested lens are described, when the two scatter plates are not in the conjugal planes of tested lens.

The principle of Hadamard transform imaging is analyzed, and the specific features of Hadamard transform imaging are discussed with emphasis placed on the basic performance and the channel capacity of the signal chain. An analyzing method for the minimum signal amount that can be detected in the non- ideal situation where there are disturbances in the sensing system and photon noise in the signal is discussed. The results of analysis show that the quantity of system signal in a chain is only about half the total of all signals and the capacity of the signal chain is not fully utilized when the S- matrix is used to carry out the code measurement, so the minimum amount of detectable signals is rather large. The method of Hadamard transform imaging with maximum signal capacity and the analyzing method for the minimum detectable signals are discussed. Based on the transmission and diffraction theory of near-field optics and the principle of Hadamard transform with maximum capacity, an imaging method with nano-resolution is proposed.

A simple phase-shift interference methods using a couple of double slits and a cylindrical lens are proposed to measure the phase modulation characteristics of liquid crystal spatial light modulator (LC-SLM). The experimental results employed the proposed in this paper are presented.

In the laser diode interferometer with a photothermal wavelength modulation which is used for optical fine measurement, intensity fluctuations of light source cause measurement errors through the fluctuations decrease greatly as compared with the injection current modulation of wavelength. In this paper, we investigated the effect of photothermal modulation parameters of wavelength on the intensity fluctuations of light source. Choosing appropriate photothermal-modulation parameters, we measured microdisplacements of object with a high measurement accuracy.

There are a few difference in the characters of the optical sensors of the particle's counter when it is been making because of the technical difference between the sensors. So, the criterion must been used for the sensors. In the traditional method, only one or two kinds of the standard particles is used as criterion because that the continual function of distribution of the particles can not be gotten from an old data processing method. That is to say there is not reflected absolutely for the characters of the sensor itself because of the non-linearity and continuity of the distribution. And than, the effecting of the criterion of the counter is weakening greatly. In this paper, a new infinite channels concept and a probability function are put forward, through which, the continual distribution function of the particles can be gotten by using the technology of the A/D conversion, coding channels, data address and sum. Three kinds of the distribution function of the standard particles are used as criterion, the criterion can be completed through the comparing the standard function and real-measuring function. At last, the debugging is very simple in the Electro-circuit instead of the optics and the effect of it is enhanced greatly.

There is very strong need to test mid-frequency power spectrum density (PSD) for optical surface used in high power laser system, aerospace high resolution camera, astronomy optical system, and X-ray optics, etc. To improve measurement accuracy and remove the error, the calibration of frequency response function for a phase-shifted interferometer must be done before PSD is tested by this interferometer. In this paper, the intensity function contributed by three plane-waves interference is given at first. On basis of this function, the sinusoidal phase grating with variable frequency formed by two plane-waves interference with appropriate ratio of two amplitudes is discussed and is used to calibrate the frequency response function of an interferometer. A test example is given and some error sources are pointed out and studied.

A new improved unwrapping algorithm based on the combination of modulation and phase fitting reliability is presented. For the measurement of the sand-like object and the surface with complex reflectivity, the noises such as saturation/cut-off and quasi-speckle in the fringe images are important error sources. The phase unwrapping algorithm only based on fringe modulation is not enough to bypass these error points. In this paper, the characteristics of the phase measurement errors caused by saturation/cut-off are analyzed, and a new phase reliability criterion that is sensitive to both modulation and some intensity noises is defined to reduce the unwrapping errors. With this new reliability criterion and 'flood' unwrapping algorithm, the phase unwrapping is implemented along the more reliable path and the errors are limited in the minimum areas.

Two major parts of application of CAD in footwear design are studied: the development of last surface; computer-aided design of planar shoe-template. A new quasi-experiential development algorithm of last surface based on triangulation approximation is presented. This development algorithm consumes less time and does not need any interactive operation for precisely development compared with other development algorithm of last surface. Based on this algorithm, a software, SHOEMAKER^TM, which contains computer aided automatic measurement, automatic development of last surface and computer aide design of shoe-template has been developed.

Fourier transform profilometry (FTP) is a popular method for automatic 3-D shape measurement, which has been widely used in many fields. Now a new method for improving the precision of FTP is presented, in which a gray image of the measured object is captured by CCD camera and used to eliminate the zero frequency component of the deformed pattern. This results in improving the measurement precision and the range of FTP. Theoretical analysis and experiments verify that this method achieves the measurement precision as π phase-shifting technique does, and the experimental setup is simpler because of no phase-shift device.

Remote fiber test systems are based on technique of optical time domain reflectometry (OTDR) and, in particular, on comparison check and current traces. Precision of tests is depended on choice of estimates and criterions of trace deviations. Estimates of deviations must be most sensitive to fiber optic parameter deviations. On other hand, its must be lowest sensitive to OTDR parameter deviations. The ways of mention problem decision are discussed. We offer one of solutions. This solution is based on analytical-statistical model. Some samples of numerical and experimental results are represented. Fiber optic communication lines, comparative method, OTDR, check traces, current traces, estimate, criterion of deviation, analytical-statistical model.

During fiber optic communication lines restoration often appear optical cable short insert joint quality control needs. It is problem to measure of short cable insert fiber splice losses on long-haul optical communication lines. This problem is caused by limits of dynamic range and resolution of optical time domain reflectometer (OTDR). We present overview of ways of short cable insert optical power losses control on long- haul optical communication lines. Theoretical and experimental proof some of this methods is considered. Numerical results are represented. A good agreement of theoretically predicted and experimental values is demonstrated.

Since Moire metrology has the advantages such as non-contact, high accuracy, more automatic and high speed, so it is widely used in many fields. But it has some difficulties for large object measurement. For this reason, we proposed a new fringe- pattern stitching algorithm. The algorithm is simple and easy to achieve. Computer simulation prove that this algorithm is feasible.

More than four intensity values will become cumbersome if the space bandwidth product of the CCD camera is to be fully exploited. But the shortest algorithms are also the ones that are most sensitive to intensity noise, mechanical vibration, and errors in phase-shifting. This paper presents the four- frame shorter phase demodulation algorithm for PSI which nearly insensitive to linear error.

The methods of surface irregularity testing and characteristic parameter measurement for aspherical mirrors are studied experimentally and computer-simulatively. An accurate method for paraxial curvature radius measurement of aspherical mirrors by a special micrometric rod, in the meantime of testing of surface irregularity, is described. Finally, the measurement accuracy is analyzed.

In this paper, a testing method for optical polished surface in level instrumentation using Atomic Force microscope (AFM) is presented, and some results reached to nanmometer RMS are listed. In the paper it is indicated that different size of polished platforms are formed as difference of optical polished method and period. This research has important significance for improving optical polishing technology and obtaining supersmooth polishing surface.

This paper discussed the test of a wavefront with large aperture using synthetic wavefront method. This method means the whole tested wavefront was divided into a limited numbers of sub-apertures and Moire fringe moving was used to measure the average slopes of wavefront on the sub-apertures and then the whole wavefront was synthesized. The paper dealt an actual large aperture optical system with 500 mm diameter and 13 m focal length.

The Space Solar Telescope (SST) is being developed in Beijing Astronomical Observatory. Two sets of star sensors are needed to fit the requirement of high accuracy attitude determination of SST. The Attitude Determination and Control System (ADCS) of SST is narrated in this paper. How to mount and use the Star Sensors on SST is introduced. The structure of the data handling system and the features such as the precision, field of view (FOV), mass and power consumption of the Star Sensor are given. To elevate accuracy affected by designing and manufacturing of optical lens, mechanical and electrical parts, a calibration correction should be applied. The development of algorithms based on 'triangle set' for the recognition of star patterns, especially the consideration of preventing SST from 'lost in space' is discussed too. The altitude of SST is calculated by the valid data of the Star Sensors and the Sun Guide Telescope. The test results shows that the Star Sensor researched and developed by us can be used not only for SST, but also for other satellites.

In modern high power laser, reflected and transmitted wavefronts of optical components are being specified by the power spectral density function (PSD). In order to ensure accurate measurements of PSD of optical components, the test systems must be calibrated. This paper presents the results of the components wavefront measurements using large aperture laser Fizeau phase shifting interferometer. This paper also describes the testing results of optical components in size from approximately 100 mm X 100 mm to 240 mm X 480 mm, substrate including UBK7 glass, KDP crystal, Nd-glass. These measurements are performed after polishing, after coating and in Brewster. Using these data, we can qualify optical components and improve our fabrication processes under optics development program.

The optical scattering characteristics of two kinds of the rough costing surface with different materials ZrO₂ 8Y₂O₃ and NiCrAlY applied the plasma-thermal spraying are studied in this paper. The micrographs with different magnification of the thermal sprayed coating surfaces have been taken by a scan electron microscope (SEM). In addition, the intensity distribution of the spatial scattering has also been gotten using an He-Ne laser beam to irradiate the rough surface of the plasma-sprayed coating and compared with others spatial scattering out of reflection spot of a smooth glass plane. The experiment results shown that different coating material and the plane have different scattering distribution in space and can use a laser system with Gauss-shaped which have different light spot diameter to project on the rough surface of the thermal sprayed coating to measure some parameters.

With the Fresnel diffraction theory and Collins equation, the propagation of power spectral density (PSD) of wave-front with random spatial distribution is studied. The theoretical analysis for the propagation of PSD in some typical optical systems is concerned, and the detail simulant results are also given.

A phase-shifting method for circular grating Moire technique is introduced in this paper. The phase-shifting technique and the polarization method are combined to develop the phase- shifting of the circular grating Moire pattern, which is formed by Michelson interferometer through a series of simple components with some necessary polarization sections in the light path. It is a precise and applicable method and it can be performed in an ordinary situation.

Using a known delay interval produced by the standard flat lens and the optical film as the time standards for detecting ultrashort laser pulses, this paper have studied the standard measurement methods of time calibration of picosecond (10^-12S) and femtosecond (10^-15S) laser pulses respectively through Michelson-interference light path.

A fiber polarized-light Interferometer for high precise measurement of fabrication is introduced in this paper. This is a novel fiber senior combined polarized-light interference technology and fiber sensor technology. The accuracy of this method is 10^-2 nm in theory. It is suitable to on-line non-contact measurement and monitor in the production procedure. The principle, research and analysis of experimental results of this interferometer are described.

In this paper, we introduce a method that inspects the size and form-and-position tolerance of mirror's fitting hole in a high precision turning-and-boring coordinate lathe using rotating pick-up measurement. We elaborate the design of method of measurement and the key way for manufacturing the aided tools. The methods of assembly, of leveling and be concentric the mirror are also included. Meanwhile we explain the detail procedure of measurement and method of data acquisition and matters needing attention in the measurement. The main factor that affects the accuracy and its processing method is also reported in this paper.

In order to adjust and test 500 mm-caliber, 5m-focus resource satellite camera, basing on no focal-power adjustment, we have designed and produced a unique parallel light tube. This tube focus is 20 m, but tube-length is only 8 m different from an old by using magnifying-adjustment technology. Which is an internal pioneer, has a novel shape and longest focus. Because shorter tube length, it is influenced smaller by environment. The study open an new road to without taking out vacuum and low manufacturing expense. This paper introduces the key technology of design, adjusting and testing about the tube. At last relates manufacturing experience and improving thought.

As a practical monitoring tool for measurements of surface roughness and micro-displacement, an optical implementation of the method based on light scattering for measuring surface roughness and optical triangulation for measuring micro- displacement is proposed. The technique enables evaluation of the surface roughness and micro-displacement of specimen by using only one device. The measuring principle and basic analysis applied in the design are described in detail, after which the validity of the principle is demonstrated by the results of experimental evaluations. Experimental results show that micro-displacement measuring linear range within ± 300 μm can be obtained for measurements of specimen of surface roughness with R_a from 0.005μm to 0.1 μm.

When a fiber with four layers is illuminated by a laser beam collimated perpendicular to its axis, an asymmetry in the frontscattered light pattern will be observed. In our opinions, the eccentricity of fiber core results in it. We deduced the formula and achieved the intensity display from the different path between refracted rays by whole four layers and reflected rays by the fiber core using geometric ray tracing, and calculated the interference geometrically between the refracted rays that traverse whole four layers and one that go through only the outside three layers. The latter is responsible for the modulation of the intensity display. We found that the theoretical values nearly agreed with the experiment and the 5% eccentricity of the fiber core can be inspected. At the same time, this method can be used to in- line inspection of the eccentricity for the fiber manufacturing.

The active optical components, including deformable mirrors, tip-tilt mirrors, optical precision translational devices, and active mirrors, can be used to control wavefront, direction, path length of optical beams as well as the optical figure of mirrors. They make optical systems adjustable and controllable and endow the optical systems with flexibility and adaptability. In recent 20 years, a series of active components have been developed in Institute of Optics and Electronics, CAS., and used in adaptive optical systems, tracking systems and laser systems. In this paper the main specifications of these components will be described. Some typical results of systems using these components will be presented too.

Center for Optics Manufacturing (COM) technology developments have been redefining the capabilities and competitive dimension of the precision optics manufacturing industry. These developments include computer-controlled deterministic microgrinder and magnetorheological finishing systems that can produce spherical, aspheric and freeform optical surface form and figure accuracy in minutes, compared to the traditional manufacturing techniques that can take weeks. COM developed computer numerically controlled machining and finishing systems are a basic necessity in the manufacturer's battle to maximize flexibility, increase competitiveness, and achieve consistent high-yield product quality.

Glass molding is an advantageous method to manufacture aspherical lenses. However, it was not applicable for aspherical lenses with large aperture. We have succeeded in the development and manufacturing of glass molded aspherical lenses with large diameter of 60.5 mm by newly developed molding machine, process control and new material of mold.