This PDF file contains the front matter associated with SPIE Proceedings Volume 8896, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.

Precision glass molding has a well-documented effect of a decrease in the index of refraction of the glass during the molding process. This index drop has such significant value that optical designs for molded lenses must take into account the index drop to accurately determine the optical performance of the final lens. Widespread adoption of chalcogenide glasses for molded infrared optics has raised a series of questions as to the behavior of these glasses under molding conditions. This paper will investigate the index of refraction changes in two different chalcogenide glasses and determine if these changes are significant enough for optical designers to consider in their designs.

Panoramic objectives are becoming, due to the availability of large area digital sensors, a diffuse optical system to catch very wide field of view (FoV). Typical panoramic lens have a view angle of 360° in azimuth (the plane orthogonal to the optical axis), just like a fish-eye, and plus and minus tens of degrees in elevation angle, i. e. above and below the horizon. Most common panoramic lenses use a curved, usually aspheric, mirror placed in front of a commercial objective to capture a 360° area around the horizon. More recent design use a catadiopter instead of a mirror. Both the solutions have the draw-back effect to obscure the frontal view of the objective, producing the classic "donut-shape" image in the focal plane. We present here a panoramic lens in which the frontal field is make available to be imaged in the focal plane, by means of a frontal optics, together with the panoramic field, producing a FoV of 360° in azimuth and 260° in elevation; it have then the capabilities of a fish eye plus those of a panoramic lens: we call it hyper-hemispheric lens. We design also a lens in which the frontal optics have a different paraxial focal length with respect to the equivalent panoramic; with this solution one can image, in the same sensor, the panoramic field plus an enlargement of a portion of it: that's the bifocal panoramic lens. Both the lenses have been designed and realized and we show here the optical scheme, the nominal performances and some pictures as an example.

In recent years, thermal detectors with a 17 μm pixel pitch have become well-established for use in various applications, such as thermal imaging in cars. This has allowed the civilian infrared market to steadily mature. The main cost for these lens designs comes from the number of lenses used. The development of thermal detectors, which are less sensitive than quantum detectors, has compelled camera manufacturers to demand very fast F-numbers such as f/1.2 or faster. This also minimizes the impact of diffraction in the 8-12 μmm waveband. The freedom afforded by the choice of the stop position in these designs has been used to create high-resolution lenses that operate near the diffraction limit. Based on GASIR^®1, a chalcogenide glass, two-lens designs have been developed for all pixel counts and fields of view. Additionally, all these designs have been passively athermalized, either optically or mechanically. Lenses for cooled quantum detectors have a defined stop position called the cold stop (CS) near the FPA-plane. The solid angle defined by the CS fixes not only the F-number (which is less fast than for thermal detectors), but determines also the required resolution. The main cost driver of these designs is the lens diameter. Lenses must be sufficiently large to avoid any vignetting of ray bundles intended to reach the cooled detector. This paper studies the transfer of approved lens design principles for thermal detectors to lenses for cooled quantum detectors with CS for same pixel count at three horizontal fields of view: a 28° medium field lens, an 8° narrow field lens, and a 90° wide field lens. The lens arrangements found for each category have similar lens costs.

Range-gated active imaging has significantly been improved in the recent past. Due to the availability of high power laser diodes around 800-860 nm, it is now possible to find off-the-shelf systems working with very sensitive light intensifier and laser diodes. On the other hand, eye-safe systems working around 1.5 μm suffer from a lack of intensified sensor in the SWIR band. The only existing intensified sensors require the use of high power pulsed laser sources for the illumination. Consequently, the type of source (diode or solid-state laser) gives fundamental differences between the two types of system. The first technique which uses laser diodes, μchip or fiber lasers, is called "accumulation" imaging. These sources are characterized by a low-pulse power and high repetition rate, mostly around a few tens of kHz. Here, each image is the result of the accumulation of hundred of pulses during the frame time. The second technique which uses a solid-state laser illumination is called "flash" imaging. Here, each image is the result of a unique high power illumination of the scene at low repetition rate, mostly around the video rate. In this paper, we investigate the theoretical and practical differences between these two imaging modes and its influence on image quality, on sensitivity to day light or stray light, on fog penetration capacity, on its sensitivity to turbulences and on laser safety (NOHD). For comparative experimental purposes, we've built a range-gated active imaging system which allows the investigation of both methods. We've carried out precise comparative studies between the two acquisition methods.

Laser Gated-Viewing Advanced Range Imaging (LGVARI) methods sample range information in a wide range area with super-resolution from a few sampling points. In this paper three different methods are investigated: the Coding of Range- Gates, the Compressed Sensing Range Imaging and a hybrid method of the aforementioned LGVARI methods. In contrast to classical range imaging methods based on Nyquist sampling, the range information is not directly visible in the single images and has to be extracted from a complete sequence by means of computational optics. With LGVARI it is possible to sample range information from only a few sampling points (i.e. images) with super-resolution far beyond the limit of the Nyquist sampling theorem. It is shown that the three methods have a compression rate of < 5%.

Laser diode stacks are interesting laser sources for active imaging illuminators. They allow the accumulation of large amounts of energy in multi-pulse mode, which is well suited for long-range image recording. Even when laser diode stacks are equipped with fast-axis collimation (FAC) and slow-axis collimation (SAC) microlenses, their beam parameter product (BPP) are not compatible with a direct use in highly efficient and compact illuminators. This is particularly true when narrow divergences are required such as for long range applications. To overcome these difficulties, we conducted investigations in three different ways. A first near infrared illuminator based on the use of conductively cooled mini-bars was designed, realized and successfully tested during outdoor experimentations. This custom specified stack was then replaced in a second step by an off-the-shelf FAC + SAC micro lensed stack where the brightness was increased by polarization overlapping. The third method still based on a commercial laser diode stack uses a non imaging optical shaping principle resulting in a virtually restacked laser source with enhanced beam parameters. This low cost, efficient and low alignment sensitivity beam shaping method allows obtaining a compact and high performance laser diode illuminator for long range active imaging applications. The three methods are presented and compared in this paper.

A detector which can detect a broad range of explosives without false alarms is urgently needed. Vibrational spectroscopy provides specific spectral information about molecules enabling the identification of analytes by their “fingerprint” spectra. The low detection limit caused by the inherent weak Raman process can be increased by the Surface Enhanced Raman (SER) effect. This is particularly attractive because it combines low detection limits with high information content for establishing molecular identity. Based on SER spectroscopy we have constructed a modular detection system. Here, we want to show a combination of SER spectroscopy and chemometrics to distinguish between chemically similar substances. Such an approach will finally reduce the false alarm rate. It is still a challenge to determine the limit of detection of the analyte on a SER substrate or its enhancement factor. For physisorbed molecules we have applied a novel approach. By this approach the performance of plasmonic substrates and Surface Enhanced Raman Scattering (SERS) enhancement of explosives can be evaluated. Moreover, novel nanostructured substrates for surface enhanced IR absorption (SEIRA) spectroscopy will be presented. The enhancement factor and a limit of detection are estimated.

A novel Sagnac fiber optic sensor employing time delay estimation for distributed detection and location is proposed and demonstrated. The sensor employs Sagnac interferometer as interfering unit. A broadband, low-coherence source is spectrally sliced into two wavelength bands using wavelength division multiplexer. Therefore, the sensor consists of two Sagnac interferometers, multiplexed with a broadband light source, interfering unit and sensing fiber by wavelength division multiplexer, and hence four detected signals with two different wavelengths are obtained. After the demodulation scheme based on 3×3 coupler, two signals with fixed time delay are achieved and the location of the disturbance gained by time delay estimation enables the localization comparably accurate. Experimental results show that the sensor is especially advantageous for low location error to the application of intrusion detecting.

Recently Sofradir joined a very small circle of IR detector manufacturers with expertise every aspect of the cooled and uncooled IR technologies, all under one roof by consolidating all IR technologies available in France. These different technologies are complementary and are used depending of the needs of the applications mainly concerning the detection range needs as well as their ability to detect in bad weather environmental conditions. SNAKE (InGaAs) and SCORPIO LW (MCT) expand Sofradir's line of small pixel pitch TV format IR detectors from the mid-wavelength to the short and long wavelengths. Our dual band MW-LW QWIP detectors (25μm, 384×288 pixels) benefit to tactical platforms giving an all-weather performance and increasing flexibility in the presence of battlefield obscurants.

In parallel we have been pursuing further infrared developments on future MWIR detectors, such as the VGA format HOT detector that consumes 2W and the 10μm pitch IR detector which gives us a leading position in innovation. These detectors are designed for long-range surveillance equipment, commander or gunner sights, ground-to-ground missile launchers and other applications that require higher resolution and sensitivity to improve reconnaissance and target identification. This paper discusses the system level performance in each detector type.

We report on materials and technology development for short-wave infrared photodetectors based on InGaAs p-i-n and avalanche photodiodes (APDs). Using molecular beam epitaxy for the growth of thin layers with abrupt interfaces, which are required for optimized APD structures, excellent crystalline quality has been achieved for detector structures grown on 3-inch InP substrates. For the fabrication of focal plane detector arrays, we employed a mesa etching technology in order to compare the results with the commonly utilized planar technology. Camera detector arrays as well as test structures with various sizes and geometries for materials and process characterization are processed using a dry-etch mesa technology. Aspects of the process development are presented along with measured dark-current and photo-current characteristics of the detector devices.

Optical antennas hold great promise for increasing the efficiency of photovoltaics, light-emitting devices, and optical sensors¹. This paper discusses one strategy to achieve frequency selective detection at mid-infrared region, which utilize the plasmonic absorption nanoantenna. The infrared devices realized by such nanoantenna array have merits such as more flexibility of frequency selectivity, and its highlights of polarization properties, which will develop increased functionality for next generation focal plane arrays². We investigated one example of such nanoantenna devices to tune its plasmonic resonance for achieving frequency selectivity and polarization properties. We also demonstrated its multiplex band absorption, and one tactics to broaden its absorption spectrum. The broad infrared sensitivity of nanoantenna devices would enable multiplex bands infrared imaging detectors. The optical properties of such examples are simulated and measurement which shows perfect absorption in certainty frequency-band. By exploiting nanoantenna as light-harvesting and carrier generation element, plasmonic absorption nanoantenna devices would realize both polarization- and wavelength-selective detection, which would overcome the band gap limitations of existing semiconducting materials.

Since the advent of the laser in 1960, the protection of human eyes and sensors against intended or unintended damage by laser radiation is a hot research topic. As long as the parameters of a laser source such as the wavelength and the output power are known, adequate laser safety can be ensured simply by utilizing conventional laser protection filters which are based on absorption or interference effects. This is typically the case in cooperative environments like a laboratory or industrial facilities. A very different situation prevails in military defense or civil security. There, the parameters of encountering laser threats are usually unknown. Protection measures, helping against all types of laser threats, are the long desired objective of countless research activities. The biggest challenge in finding an effective measure arises from single laser pulses of unknown wavelength. The problem demands for a passive protection concept and may be based for example on intensity dependent effects. Moreover, the requested solutions shall comprise add-on possibilities like thin films to be put on existing optics, windshields or glasses. Unfortunately, such an all-embracing solution is still far out of reach.

The Fraunhofer IOSB has been working on the evaluation and development of non-conventional laser protection methods for more than 20 years. An overview of the past and present research activities shall be presented, comprising protection measures against laser damaging and laser dazzling.

Si based sensors, in particular CMOS Image sensors, have revolutionized low cost imaging systems but to date have hardly been considered as possible candidates for gun muzzle flash detection, due to performance limitations, and low SNR in the visible spectrum. In this study, a CMOS Single Photon Avalanche Diode (SPAD) module is used to record and sample muzzle flash events in the visible spectrum, from representative weapons, common on the modern battlefield. SPADs possess two crucial properties for muzzle flash imaging - Namely, very high photon detection sensitivity, coupled with a unique ability to convert the optical signal to a digital signal at the source pixel, thus practically eliminating readout noise. This enables high sampling frequencies in the kilohertz range without SNR degradation, in contrast to regular CMOS image sensors. To date, the SPAD has not been utilized for flash detection in an uncontrolled environment, such as gun muzzle flash detection. Gun propellant manufacturers use alkali salts to suppress secondary flashes ignited during the muzzle flash event. Common alkali salts are compounds based on Potassium or Sodium, with spectral emission lines around 769nm and 589nm, respectively. A narrow band filter around the Potassium emission doublet is used in this study to favor the muzzle flash signal over solar radiation. This research will demonstrate the SPAD's ability to accurately sample and reconstruct the temporal behavior of the muzzle flash in the visible wavelength under the specified imaging conditions. The reconstructed signal is clearly distinguishable from background clutter, through exploitation of flash temporal characteristics.

Snipers and other optically guided weapon systems are serious threats in military operations. We have studied a SWIR (Short Wave Infrared) camera-based system with capability to detect and locate snipers both before and after shot over a large field-of-view. The high frame rate SWIR-camera allows resolution of the temporal profile of muzzle flashes which is the infrared signature associated with the ejection of the bullet from the rifle. The capability to detect and discriminate sniper muzzle flashes with this system has been verified by FOI in earlier studies. In this work we have extended the system by adding a laser channel for optics detection. A laser diode with slit-shaped beam profile is scanned over the camera field-of-view to detect retro reflection from optical sights. The optics detection system has been tested at various distances up to 1.15 km showing the feasibility to detect rifle scopes in full daylight. The high speed camera gives the possibility to discriminate false alarms by analyzing the temporal data. The intensity variation, caused by atmospheric turbulence, enables discrimination of small sights from larger reflectors due to aperture averaging, although the targets only cover a single pixel. It is shown that optics detection can be integrated in combination with muzzle flash detection by adding a scanning rectangular laser slit. The overall optics detection capability by continuous surveillance of a relatively large field-of-view looks promising. This type of multifunctional system may become an important tool to detect snipers before and after shot.

Infrared guided missile seekers utilizing pulse width modulation in target tracking is one of the threats against air platforms. To be able to achieve a “soft-kill” protection of own platform against these type of threats, one needs to examine carefully the seeker operating principle with its special electronic counter-counter measure (ECCM) capability. One of the cost-effective ways of soft kill protection is to use flare decoys in accordance with an optimized dispensing program. Such an optimization requires a good understanding of the threat seeker, capabilities of the air platform and engagement scenario information between them. Modeling and simulation is very powerful tool to achieve a valuable insight and understand the underlying phenomenology. A careful interpretation of simulation results is crucial to infer valuable conclusions from the data. In such an interpretation there are lots of factors (features) which affect the results. Therefore, powerful statistical tools and pattern recognition algorithms are of special interest in the analysis. In this paper, we show how self-organizing maps (SOMs), which is one of those powerful tools, can be used in analyzing the effectiveness of various flare dispensing programs against a PWM seeker. We perform several Monte Carlo runs for a typical engagement scenario in a MATLAB-based simulation environment. In each run, we randomly change the flare dispending program and obtain corresponding class: “successful” or “unsuccessful”, depending on whether the corresponding flare dispensing program deceives the seeker or not, respectively. Then, in the analysis phase, we use SOMs to interpret and visualize the results.

Infrared (IR) camera modules for the LWIR (8-12_m) that combine IR imaging optics with microbolometer focal plane array (FPA) sensors with readout electronics are becoming more and more a mass market product. At the same time, steady improvements in sensor resolution in the higher priced markets raise the requirement for imaging performance of objectives and the proper alignment between objective and FPA. This puts pressure on camera manufacturers and system integrators to assess the image quality of finished camera modules in a cost-efficient and automated way for quality control or during end-of-line testing. In this paper we present recent development work done in the field of image quality testing of IR camera modules. This technology provides a wealth of additional information in contrast to the more traditional test methods like minimum resolvable temperature difference (MRTD) which give only a subjective overall test result. Parameters that can be measured are image quality via the modulation transfer function (MTF) for broadband or with various bandpass filters on- and off-axis and optical parameters like e.g. effective focal length (EFL) and distortion. If the camera module allows for refocusing the optics, additional parameters like best focus plane, image plane tilt, auto-focus quality, chief ray angle etc. can be characterized. Additionally, the homogeneity and response of the sensor with the optics can be characterized in order to calculate the appropriate tables for non-uniformity correction (NUC). The technology can also be used to control active alignment methods during mechanical assembly of optics to high resolution sensors. Other important points that are discussed are the flexibility of the technology to test IR modules with different form factors, electrical interfaces and last but not least the suitability for fully automated measurements in mass production.

A cavity blackbody is the appropriate IR reference source for IR sensors which require high radiance levels. It combines high emissivity independent from wavelength and high speed warm up and high stability thanks to its light trap structure. However, the inconvenient of this structure is that it leads to a prohibitive cooling time. HGH developed a method to speed up the cooling time.

We report realistic performance simulation results for a new MWIR camera. It is designed for early detection of long distance missile plumes over few hundreds kilometer in the distance range. The camera design uses a number of refractive optical element and a IR detector. Both imaging and radiometric performance of the camera are investigated by using large scale ray tracing including targets and background scene models. Missile plume radiance was calculated from using CFD type radiative transfer algorithm and used as the light source for ray tracing computation. The atmospheric background was estimated using MODTRAN utilizing path thermal radiance, single/multiple scattered radiance and transmittance. The ray tracing simulation results demonstrate that the camera would satisfy the imaging and radiometric performance requirements in field operation at the target MWIR band.

The Materials and Components for Missiles Innovation and Technology Partnership (ITP) is a research programme supporting research for guided weapons at Technology Readiness Levels 1 to 4. The Anglo-French initiative is supported by the DGA and the MoD, with matched funding from industry. A major objective is to foster projects which partner UK and French universities, SMEs and larger companies. The first projects started in January 2008 and the first phase completed in spring 2013. Providing funding is secured, the next phase of the programme is due to start later in 2013. Selex ES leads Domain 3 of the MCM-ITP which develops Electro-Optic sensor technology. In collaboration with DGA, MoD and MBDA, the prime contractor, we identified 4 key objectives for the first ITP phase and focussed resources on achieving these. The objectives were to enable better imagery, address operationally stressing scenarios, provide low overall through life cost and improve active and semi-active sensors Nine normal projects and one ITP innovation fund project have been supported within the domain. The technology providers have included 3 SMEs and 8 research centres from both the United Kingdom and France. Highlights of the projects are included. An outline of the priorities for the domain for the new phase ise provided and we encourage organisations with suitable technology to contact us to get involved.

Autonomously operating semi-stationary multi-camera components are the core modules of ad-hoc multi-view methods. On the one hand a situation recognition system needs overview of an entire scene, as given by a wide-angle camera, and on the other hand a close-up view from e.g. an active pan-tilt-zoom (PTZ) camera of interesting agents is required to further increase the information to e.g. identify those agents. To configure such a system we set the field of view (FOV) of the overview-camera in correspondence to the motor configuration of a PTZ camera. Images are captured from a uniformly moving PTZ camera until the entire field of view of the master camera is covered. Along the way, a lookup table (LUT) of motor coordinates of the PTZ camera and image coordinates in the master camera is generated. To match each pair of images, features (SIFT, SURF, ORB, STAR, FAST, MSER, BRISK, FREAK) are detected, selected by nearest neighbor distance ratio (NNDR), and matched. A homography is estimated to transform the PTZ image to the master image. With that information comprehensive LUTs are calculated via barycentric coordinates and stored for every pixel of the master image. In this paper the robustness, accuracy, and runtime are quantitatively evaluated for different features.

Spectral imagers in the Long Wave IR spectral range (8 to 12 microns) suffer from the problem of high production costs because the existing commercial cooled array detectors are expensive, and in fact they are prohibitively expensive for many applications. As a result, the drive to lower the cost of Long Wave IR spectral imagers is strong: this is the main motivation for CI to investigate a new design that allows these spectral imagers to be more affordable. One area of possible cost reduction without relinquishing the advantages of a cryogenically cooled detector is the method used to provide the spectral information. CI Systems has developed a long wave IR (7.7 to 12.3 micron) spectral imager concept using a Circular Variable Filter (CVF), (a proprietary component based on multiple layer interference filter technology) which has advantages over the interferometric Fourier Transform method commonly used in this spectral range. The CVF method has its own development challenges; however, once proven, this concept may be more suitable and affordable for applications in which a spectral resolution of 0.5% of the wavelength (or 50 nm at 10 μ) is required. The design of the optical system must minimize background signals without being cooled to cryogenic temperatures, so we called it VIrtually COld (or VICO). CI is in the final stages of prototype building and characterization. Present initial calibration results and measurement examples are given in this paper.

The compressive sensing framework states that a signal which has sparse representation in a known basis may be reconstructed from samples obtained from a sub-Nyquist sampling rate. Due to its inherent properties, the Fourier domain is widely used in compressive sensing applications. Sparse signal recovery applications making use of a small number of Fourier Transform coe±cients have made solutions to large scale data recovery problems, i.e. images, applicable and more practical. The sparse reconstruction of two dimensional images is performed by making use of sampling patterns generated by taking into consideration the general frequency characteristics of natural images. In this work, instead of forming a general sampling pattern for infrared images of sea-surveillance scenarios, a special sampling pattern has been obtained by making use of a new iterative algorithm that uses a database containing images recorded under similar conditions to extract important frequency characteristics. It has been shown by experimental results that, the proposed sampling pattern provides better sparse recovery performance compared to the baseline sampling methods proposed in the literature.

In this paper, we investigate the application of compressive sensing theory to single detector infrared seekers. Compressive sensing is a novel signal processing technique which enables a compressible signal to be constructed using fewer measurements obtained in a specific way below the Nyquist rate. Single detector image reconstruction applications using compressive sensing have been shown to be successful. Infrared seekers utilizing single detectors suffer from low performance compared to costly focal plane array detectors. The single detector, pseudo-imaging rosette scanning seekers scan the scene with a specific pattern and process the resultant signal with signal processing methods to estimate the target location without forming an image. In this context, this type of old generation seekers can be converted to imaging systems by utilizing the samples obtained by the scanning pattern in conjunction with the compressive sensing theory framework. In this study, infrared images have been reconstructed from samples obtained by the rosette scanning pattern for different sample numbers and it has been shown that the results obtained are comparable to the results obtained by other sampling methods proposed in the literature.

The photogrammetric system in vacuum cryogenic environment is designed to measure the sharp deformation of the satellite antenna due to the thermal deformation. The method of the measurement is based on the close-range photogrammetric techniques. This system includes CCD photography assembly, scale bars, support structures and the software. A test was performed by using this system, and the sharp deformation of a reflecting antenna was measured. In the test, a plenty of data was acquired, then the measurement method was proved feasible. According to analysis, we can acquire that the relatively measurement precision by this system can reach to 1:20000.

A large-scale in-door illumination simulating system was designed and developed by Beijing Institute of Spacecraft Environment Engineering for solar illumination test requirements of a deep-space sensor. Metallic Halide Lamps and Tungsten Halogen Lamps with good accuracy and small collimating angle lanterns, which are high-power and good-match with sunlight, distribute on the wall of the laboratory in order to make good uniformity in an area of 20m×20m. Design results show that, firstly, total average radiation intensity is 400.4W/m². Secondly, intensity are 48.5W/m² in 600nm～700nm and 5.1W/m2 in 965nm～995nm. Thirdly, incident angle of the system range from 15° to 45°. Fourthly, uniformity with 15°, 30° and 45° are ±12.4%, ±8.1% and ±14.9% respectively. Finally, shadow profile in the area is clear. The results of acceptance test match the design results very well and meet the requirements totally. The system has been used in laboratory test of the detector successfully.

Thermal imagers and used therein infrared array sensors are subject to calibration procedure and evaluation of their voltage sensitivity on incident radiation during manufacturing process. The calibration procedure is especially important in so-called radiometric cameras, where accurate radiometric quantities, given in physical units, are of concern. Even though non-radiometric cameras are not expected to stand up to such elevated standards, it is still important, that the image faithfully represents temperature variations across the scene. Detectors used in thermal camera are illuminated by infrared radiation transmitted through an infrared transmitting optical system. Often an optical system, when exposed to uniform Lambertian source forms a non-uniform irradiation distribution in its image plane. In order to be able to carry out an accurate non-uniformity correction it is essential to correctly predict irradiation distribution from a uniform source. In the article a non-uniformity correction method has been presented, that takes into account optical system’s radiometry. Predictions of the irradiation distribution have been confronted with measured irradiance values. Presented radiometric model allows fast and accurate non-uniformity correction to be carried out.

Recent terrorist attacks and possibilities of such actions in future have forced to develop security systems for critical infrastructures that embrace sensors technologies and technical organization of systems. The used till now perimeter protection of stationary objects, based on construction of a ring with two-zone fencing, visual cameras with illumination are efficiently displaced by the systems of the multisensor technology that consists of: visible technology – day/night cameras registering optical contrast of a scene, thermal technology – cheap bolometric cameras recording thermal contrast of a scene and active ground radars – microwave and millimetre wavelengths that record and detect reflected radiation. Merging of these three different technologies into one system requires methodology for selection of technical conditions of installation and parameters of sensors. This procedure enables us to construct a system with correlated range, resolution, field of view and object identification. Important technical problem connected with the multispectral system is its software, which helps couple the radar with the cameras. This software can be used for automatic focusing of cameras, automatic guiding cameras to an object detected by the radar, tracking of the object and localization of the object on the digital map as well as target identification and alerting. Based on “plug and play” architecture, this system provides unmatched flexibility and simplistic integration of sensors and devices in TCP/IP networks. Using a graphical user interface it is possible to control sensors and monitor streaming video and other data over the network, visualize the results of data fusion process and obtain detailed information about detected intruders over a digital map. System provide high-level applications and operator workload reduction with features such as sensor to sensor cueing from detection devices, automatic e-mail notification and alarm triggering. The paper presents a structure and some elements of critical infrastructure protection solution which is based on a modular multisensor security system. System description is focused mainly on methodology of selection of sensors parameters. The results of the tests in real conditions are also presented.

Range parameters are main factors in assessing the performance of observation devices. They can be determined on the basis of computer simulations, field or laboratory measurements, with the latter method being the most reliable and practical. The paper presents the methods used for the determination of detection, recognition and identification ranges based on well-known Johnson criteria and recently emerged TTP model. Theoretical background for both approaches are given, and the laboratory test stand is described together with brief methodology adopted for the measurements of selected, necessary characteristics of a tested observation system. The measurement results are presented and the calculated ranges for a selected set of IR cameras are given, obtained on the basis of both Johnson criteria and TTP model. Finally the results are discussed and the final thoughts on the TTP model application are presented.

Uneven response of particular detectors (pixels) to the same incident power of infrared radiation is an inherent feature of microbolometer focal plane arrays. As a result an image degradation occurs, known as Fixed Pattern Noise (FPN), which distorts the thermal representation of an observed scene and impairs the parameters of a thermal camera. In order to compensate such non-uniformity, several NUC correction methods are applied in digital data processing modules implemented in thermal cameras. Coefficients required to perform the non-uniformity correction procedure (NUC coefficients) are determined by calibrating the camera against uniform radiation sources (blackbodies). Non-uniformity correction is performed in a digital processing unit in order to remove FPN pattern in the registered thermal images. Relevant correction coefficients are calculated on the basis of recorded detector responses to several values of radiant flux emitted from reference IR radiation sources (blackbodies). The measurement of correction coefficients requires specialized setup, in which uniform, extended radiation sources with high temperature stability are one of key elements. Measurement stand for NUC correction developed in Institute of Optoelectronics, MUT, comprises two integrated extended blackbodies with the following specifications: area 200×200 mm, stabilized absolute temperature range +15 °C÷100 °C, and uniformity of temperature distribution across entire surface ±0.014 °C. Test stand, method used for the measurement of NUC coefficients and the results obtained during the measurements conducted on a prototype thermal camera will be presented in the paper.

This paper aims at the special requirement of small angle swing scanning control system (swing range is ±0.125°, swing frequency is 2Hz). We have emulated and certified the controlled device so that we make sure that the implementation of system is feasible in theory. Aiming at the key problem of the implementation of system, the algorithm and hardware design is improved and then the method of digital control is adopted so that the whole performance has improved a lot. The method can work out the difficult problem that the system control in low speed of rotation, small angle and high precision．

In this work, the applicability of charge controlled electrostatically tuneable optical filters is investigated. The filters are based on a Fabry-Pérot architecture, fabricated in a bulk micromachining process. Compared to surface micromachined devices, this design opens a path to higher optical performance due to the high planarity and low roughness of substrates but also introduces the drawback of acceleration sensitivity because of a moving mass. The common way of tuning those electrostatic actuators by applying constant voltages decreases the effective stiffness of the system and thus further increases this sensitivity for large deflections. In addition, the tuning range is limited to one third of the initial electrode spacing due to the pull-in effect. Therefore, designing voltage-controlled electrostatic actuators of such optical filters result in tough tradeoffs between initial electrode spacing, spring stiffness, supply voltage and chip area. In order to overcome the limitation of the tuning range and relax these tradeoffs, controlling the charge instead of voltage by using a switched capacitor amplifier is examined. Experiments have shown that it is possible to obtain a stable relative displacement of up to 60% limited by reflector tipping. Measuring gravity impact confirmed the expected reduced deflection dependency. Thus, it is possible to downsize the initial electrode spacing by 45% and the spring stiffness by 40% while achieving the same optical tuning range and acceleration sensitivity as in voltage mode. However, because of reflector tilting and the associated filter bandwidth degradation, a further tradeoff arises when using relative deflections greater 40 %.

We present progress on bandpass infrared interference filters with very narrow passbands to be used for sensitive trace gas and volatile compound imaging and detection and are suitable for mode selection and tuning in singlemode External Cavity Quantum Cascade Lasers. The process parameters for fabrication of such filters with central wavelengths in the 3-12 μm range are described. One representative fillter has a passband width of 6 nm or 0.14% with peak transmission of 62% and a central wavelength of 4.4μm. Theoretically, it can be tuned through about 4% by tilting with respect to the incident beam and offers orders of magnitude larger angular dispersion than diffraction gratings. We compare filters with single-cavity and coupled-cavity Fabry-Perot designs. The filters pass the tests for adhesion and abrasion as stated in MIL-C-48497.

In this paper, the current status of infrared imaging detecting technology was introduced briefly. The impact of changes of target, environment and mission on the development of infrared imaging detecting technology was analyzed. The main innovation strategies of infrared imaging detecting technology–modifying information acquisition mode, enhancing realization ability and increasing resources utilization were discussed. The promoting effects of the advancement of basic theories and the revolution of relevant technologies on the development of infrared imaging detecting technology were analyzed. The fundamental law of the development of infrared imaging detecting technology was summarized as stepwise evolution from low into high dimension detection. And the developing trends and main characteristics of future infrared imaging detecting technology were deduced based on this fundamental law. Furthermore, technology directions that should be concerned were introduced according to the development of new concept and technologies for infrared imaging detecting, especially, meeting the new requirements through new concept imaging mechanism such as novel optical technology and computing imaging.

A reliability-based structural design method for infrared cryostat is put forward to obtain a design result with a quantitative reliability index. In this method, the reliability analysis is performed by integrating the finite element software ANSYS (functioning as the deterministic analyzer) with the probabilistic engineering analysis software NESSUS (functioning as the probabilistic analyzer), in which design parameters are treated as random variables. The probability of failure and probabilistic sensitivity level of design parameters are calculated, which would provide a quantitative judgment about whether there should be a redesign and which parameters should be modified in the redesign. As an example to illustrate this method, the IR focal plane displacement induced by random vibration has been analyzed in this paper. The probability of the focal plane displacement value exceeding a critical value is calculated and the focal plane stability reliability level has been increased from 82% to 99.9999%. The method can be widely applicable in the fields where uncertainty is assumed to have a significant impact on the structural response.

The recent necessity to protect military bases, convoys and patrols gave serious impact to the development of multisensor security systems for perimeter protection. One of the most important devices used in such systems are IR cameras. The paper discusses technical possibilities and limitations to use uncooled IR camera in a multi-sensor surveillance system for perimeter protection. Effective ranges of detection depend on the class of the sensor used and the observed scene itself. Application of IR camera increases the probability of intruder detection regardless of the time of day or weather conditions. It also simultaneously decreased the false alarm rate produced by the surveillance system. The role of IR cameras in the system was discussed as well as technical possibilities to detect human being. Comparison of commercially available IR cameras, capable to achieve desired ranges was done. The required spatial resolution for detection, recognition and identification was calculated. The simulation of detection ranges was done using a new model for predicting target acquisition performance which uses the Targeting Task Performance (TTP) metric. Like its predecessor, the Johnson criteria, the new model bounds the range performance with image quality. The scope of presented analysis is limited to the estimation of detection, recognition and identification ranges for typical thermal cameras with uncooled microbolometer focal plane arrays. This type of cameras is most widely used in security systems because of competitive price to performance ratio. Detection, recognition and identification range calculations were made, and the appropriate results for the devices with selected technical specifications were compared and discussed.

When the moon and the sun light enter into the field of view of the conical scanning earth sensor (CES), the real attitude of the spacecraft will be affected because of wrong CES measurements．To solve this problem, a new method based on the CES software can discriminate the interference effect．A series of ground are designed to verify this method effectiveness, and results indicate that this method can not only give a indication of the moon, but also can eliminate effect of the moon and the sun light on the CES’s measurements．Finally, the on-orbit flight data is presented to confirm this method validity．