A polarizing Michelson interferometer for the far-infrared and millimetre regions

A polarizing Michelson interferometer for the far-infrared and millimetre regions is described. It uses a simple mechanical drive to attain high-resolution spectra with excellent frequency accuracy, as evidenced by measurements of the rotational parameters for N₂O, for which the D parameter is measured with an uncertainty of ± 190 Hz; comparable with the accuracy of microwave techniques.     

A high efficiency polarizing interferometer for the far infrared fourier-transform spectroscopy

Conclusion The new polarizing interferometer was constructed, in which all the radiation entering the interferometer can be utilized. From the experimental results in the atmosphere and for the water-vapour, it is seen that this spectrometer can work satisfactorily from 5 cm^–1 to 1/2d cm^–1. Comparison of the spectrun by this interferometer with one by the standard Michelson interferometer shows that the gain of luminosity is almost as expected. Grid with substrate causes the interference and produces the spectral response in the higher frequency region. Another configuration of two grids and two plane mirrors is proposed for the polarizing interferometer of high luminosity and of very simple design.     

A high efficiency polarizing interferometer for astronomical observations in the submillimetric region

We describe a high efficiency polarizing interferometer for astronomical observations in the submillimetric and millimetric region. The results obtained during tests at the focal plane of TIRGO (Gornergrat) lead to the conclusion that the instrument works with the expected efficiency and can be used for astronomical observations of faint sources.     

Design of polarizing interferometer in sub-millimeter wavelength range

Based upon the quasi-optical technique consideration, the dependence of polarizing interferometer properties on Gaussion beam parameters were analyzed. The formulas for PI construction design and the errors of mechanical alignment of polarizing interferometer based on Gaussian beam parameters are given.     

正交偏振180°旋转剪切干涉仪及其应用

本文报道了一台正交偏振180°旋转剪切干涉仪的工作原理和性质,并把它应用于透镜几何偏心量.轴外非对称波像差等方面的定量检测,显示了独特的功能和极高的灵敏度.     

Photothermal method of measuring weak absorption in a polarizing interferometer

Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 50, No. 5, pp. 783–790, May, 1989.     

新型偏振风成像干涉仪中偏振化方向对调制度和干涉强度的影响研究

简要论述了新型偏振风成像干涉仪的原理;分析了偏振风成像干涉仪的各光学部件的偏振化方向对调制度和干涉强度的影响;给出了起偏器的偏振化方向、干涉仪两臂λ/4波片及出射位置处λ/4波片的光轴取向偏离理想方向时干涉仪调制度和干涉强度的理论表达式;采用计算机模拟分别给出了调制度随各偏角变化的曲面图及风速、温度反演误差随各偏角变化的曲线图;给出了温度精度为5K、风速精度为20m/s时偏振化方向的误差容限.该研究对新型偏振风成像干涉仪的研究、研制提供了一定的理论依据和实践指导,对高层大气光学被动探测以及空间探测、对地观测都具有科学意义和应用前景.     

A new type of quasi-optical cavity in millimeter wave-band

A new type of cavity-the resonator of plane mirrors with dielectric tubes is analyzed theoretically and experimentally. Making use of equivalent dielectric constant method, we calculated the field distribute, quality factor, attenuate and transmission constant in the cavity. We measured the parameter of the cavity and discovered that the cavity's quality factor is high, band-width wide, modes less and structure simple.     

Polarization Sagnac interferometer with a reflective grating beam splitter

All-reflective interferometric gravitational-wave detector configurations with a diffraction grating as a power beam splitter have been proposed to reduce thermal lensing. We demonstrate the use of a diffraction grating as a polarization beam splitter in a zero-area polarization Sagnac interferometer.     

A new kind of compound solid-state quasi-optical power combiner

In this paper, a new kind of solid-state quasi-optical power combiner is presented. It consists of two or more singlecavity multiple-device power combiners and a Fabry-Perot cavity. The experimenal results using six Gunn diodes at X-band show that the total output power is higher than 400 mW, the total combining efficiency is as high as 83%, and the frequency stability is better than 10^–5.     

Far infrared spectroscopy of praseodymium magnesium nitrate using a polarizing interferometer

A number of contradictions exist in the published far i.r. spectra of praseodymium magnesium nitrate. Spectra recorded with improved spectrophotometric accuracy with a polarizing interferometer have enabled these to be resolved. Transitions from the ground doublet to the first excited singlet state of the Pr³⁺ ion showed no evidence of the small ground state splitting. The Zeeman splitting of this absorption is as predicted from the ground stateg-value but the components are of unequal width. Other features of the spectrum are described.     

Interferometric phase microscopy using slightly-off-axis reflective point diffraction interferometer

An interferometric phase microscopy (IPM) is proposed using slightly-off-axis reflective point diffraction interferometry for quantitative phase imaging. A retro-reflector consisting two mirrors is used to generate an angle between the object beam and reference beam, and a 45° tilted polarizing beam splitter is used to split the horizontal and vertical components of the both beams. Two carrier interferograms with π/2 phase-shift can be acquired in one shot, and the phase distribution of a thin specimen can be retrieved using a fast reconstruction method. The new IPM without loss in the utilization of the input-plane field of view combines the real time and optimizing detector bandwidth measurement benefit associated with slightly-off-axis method, high stability associated with common path geometry, and simplicity in terms of procedure and setup. Experiments are carried out on both static and dynamic specimens to demonstrate the validity and stability of the proposed method.     

The design and preparation of a Fabry-Perot polarizing filter

A novel single-cavity narrowband Fabry-Perot （FP） polarizing filter at normal incidence, constructed from a sandwich structure with sculptured anisotropic space layer and symmetric isotropic HR mirrors, is designed and prepared. The optical performances of transmittance, phase shift, central wavelength, and bandwidth for two polarized states are analyzed with the characteristic matrix. The numerical studies accord reasonably well with the experimental results. It is demonstrated that the polarization state of the electromagnetic wave and phase shift can be modulated by employing an anisotropic space layer in the polarizing beam splitter system. The birefringence of the anisotropic space layer provides a sophisticated phase modulation by varying the incidence angles over a broad range to have a wide-angle phase shift.     

Character recognition: A new multiple filter

A multiple filter obtained with only one exposure is proposed for character recognition by means of correlation filtering. The filter is obtained by Fourier holography from a transparency in which the different characters are matched to a determined angle among them.     

Multipass interferometer using a filamentary spatial filter

A multiple pass interferometer using a filamentary spatial filter is developed. We can change the sensitivity of the interference fringe pattern by selecting the order of multiply reflected image without reduction of the fringe visibility.     

小孔干涉仪滤波孔的研究

用惠更斯-基尔霍夫公式对小孔干涉仪的滤波孔进行计算及分析后指出:尽管滤波孔小于爱里斑,滤波孔的位置对参考波的质量仍有影响。在接收面上参考波位相有较大偏移处,往往伴有较大的光强变化(变弱)。给出实验结果,并进行了讨论。     

Analysis of the mode of operation of a polarizing interferometer in dispersive Fourier transform spectroscopy

An analysis is given of the mode of operation of a polarizing interferometer constructed in a configuration which has been widely used to measure the refractive indices of solids and liquids in the far-infrared by dispersive Fourier transform spectroscopy. It is shown how the instrument produces an inverted interferogram and that the efficiency, which is essentially constant below the cut-off region, is approximately half the peak efficiency of a conventional Michelson interferometer at the centre of the beam-splitter pass band. It is also shown how the appropriate amplitude and phase spectra of the specimen are obtained in the usual way by taking the ratio of the complex Fourier transforms of double sided specimen and background interferograms.     

A quasi-optical universal polarizer

This paper describes the design and measurement of a quasi-optical universal polarizer for use in the 100–170 GHz frequency range. The instrument may be configured to convert an arbitrary elliptical polarization state into a linearly polarized stale suitable for feeding a fixed waveguide receiver. A transmission loss of 0.15 dB was measured at 140 GHz and the rejection of the orthogonal polarization state was greater than 50 dB.The author would like to express his thanks to John Fessey and John Maduzak for useful discussions.