In the research of detecting extinction ratio of polarimeter, some significant characters are discovered. One polaroid has
perfect extinction ratio in the visible, but its extinction ratio becomes weak in near infrared (NIR) region, and the
transmittance of a pair of vertical polaroid becomes strong in NIR region. This phenomenon has been found in several
other polaroids as well. The transmittance increases greatly in NIR even if the crystal Glan-Taylor prism polarimeter with
good polarization is used. The extinction ratio of the polaroid changes from 3:100 in visible to 98:100 in NIR. More
experiments have shown that the weakening of extinction ratio and the enhancement of transmittance of a pair of vertical
polaroid in NIR are closely associated with the intensity of incident light. When the light intensity increases, the effect
becomes clearer. The transmittance exceeds the theoretical results from classical physical optics, reaching 98%. Our
results provide two aspects of applications. First, because the extinction ratio of the polaroid is related to the wavelength
of incident light, the polaroid can be used in definite spectral range. Second, a pair of vertical polaroid can perfectly filter
the visible light, while making NIR light transmit. This research result can provide some conveniences at IR spectrum,
IR photography, IR imaging and IR detection.
Based on the principle that residual stress in crystal lattice leads to change of distance among atoms, an approximate
linear relationship between Raman shift and suffered strain of fibers is deduced. According to the stress-strain curve, a
linear relationship between the stress and Raman shift is also deduced, and the ratio coefficient of the stress and Raman
frequency shift is given. In high intensity carbon fibers, different spectra of the carbon fibers are obtained by Raman
spectroscopy. The approximate linear relationship between the carbon fiber tensile strain and Raman shift is validated
and the stress factor is given as well. Both the theoretic and experimental results show that the stress factor is
-486.7GPa.mm. The experiment results also show that the Raman spectroscopy is a very effective method for the
microstructure residual stress measurement. This method for residual stress measurement by Raman shift is able to be
used in textile, biology, materials etc..
In order to improve the detectability of low-light imaging CCD (charge coupled devices), we have brought forward a
magnetic mirror device to apply to microchannel electron vase plate ((MEVP)) of low-light imaging system at room
temperature. After introduced the principle of restricted electron in magnetic mirror field to accumulate enough time for
low-light CCD imaging, magnetic intensity has been calculated discretionary position in the mirror, the formula of
electron's velocity direction has been given through the throat of magnetic mirror in this paper. The educed electron's
angle distribution between velocity direction and magnetic mirror axis has been simulated at 7-10 degree. This answers
for the design needs of microchannel vase plate now. The electron's loop speckle imaging has been obtained by
experiment; the result is same as theoretical value. It is proved that if the electrons educed by the magnetic mirror field at
the same cone angle and approximate speed, the gain of microchannel plate will be more stable, so that it is favorable to
reduce the noise of photoelectronic imaging.
The charge packet transfer rate is one of the most important factors of charge transfer losing (CTL) in Charge Coupled
Devices (CCD). It is important to build up a model of CCD structure parameters, charge transfer efficiency (CTE),
transfer frequency of charge packet and work temperature etc. But it is very hard to build up an exact theoretical model
and find the analytical solution neither math nor physics. The traditional discussion of the working principle of CCD
build up a nonlinear partial differential equation, but it just consider the remainder electrons concentration while integer
k=0. In this paper, we increase the result of the electrons concentration while k=1, 2,..., n, and discuss the result. A more
accreted result of the charge packet rate had been got. The result is 81 percent of the CTL which is traditionally
discussed about of CCD. Then the CTE in low temperature is discussed using the result. And the optimum frequency of
the CCD is corrected also. The correction of the charge packet rate in CCD can enhance the performance of CCD.
The modified super-wide-angle Sagnac interferometer (SASI) is designed for upper atmospheric wind measurement. The
formula of SASI's optical path difference (OPD) is derived, in which the OPD versus the sine series of incidence angle
in order of 4. The SASI's fully compensations of super-wide-angle, achromatic, thermal, wavelength-independent
thermal conditions have been investigated. The SASI configuration for the above compensations was successfully setup
by selecting correct glasses from the 113 kinds of glasses. The optimized SASI is made of ZBaF17 and QF14 glasses,
and the arm lengths are accurately configured. Based on the configuration of glass types and arm lengths of SASI, it
shows that SASI achromatic condition is satisfied synchronously for three aurora's emission lines, which are 557.7nm,
630.0nm and 732.0nm respectively. The relative error of SASI's lengths does not exceed 1%. The full field of view
(FOV) of the SASI is 6°. It is about 5° in full angle from SASI optical axis to CCD farthest corner. The first order fringe
occupies about 67% of the CCD area.
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