Wave-plate detection device and method

Abstract

The invention discloses a wave-plate detection device, comprising a light source, a polarizing arm, a sample platform for placing a wave plate to be detected, a polarization detection arm and a detector; the centers of the polarizing arm, the wave plate to be detected and the polarization detection arm are on the same line; the light emitted by the light source is polarized and modulated by the polarizing arm to become modulation polarizing light; the modulation polarization light couples the wave plate information through the wave plate to be detected, and then the modulation and polarization detection are performed on the modulation polarization light through the polarization detection arm; and then the processed modulation polarization light is received by the detector. The invention utilizes the Mueller matrix to establish the relation between the wave plate characteristic parameter and the Mueller matrix, adopts the Mueller matrix ellipsometer to measure the Mueller matrix spectroscopic data of the wave plate to be detected so as to further obtain the characteristic parameter spectral data of the wave plate to be detected. The invention obtains the all characteristic parameter spectral data of any wave plate from one time measurement, and the parameter spectral data comprise phase retardation, a fast axis azimuth, a fast-slow axis transmittance amplitude ratio angle and a depolarization index.

Description

technical field [0001] The invention belongs to the field of optical element detection, and more specifically relates to a wave plate detection device and method. Background technique [0002] The wave plate is an optical element commonly used in the field of optical instrument design and optical measurement. It can cause the two vertical components of polarized light to produce an additional optical path difference (or phase difference). The optical path difference is called the phase retardation of the wave plate. The phase retardation properties of the wave plate can be used to change the polarization state of light waves (for example, from linearly polarized light to circularly polarized light, from elliptically polarized light to linearly polarized light, etc.), or to examine the polarization state of light waves. Wave plates are usually made of birefringent crystals. Commonly used birefringent crystals include mica, gypsum, magnesium fluoride, sapphire, and crystalline...

AI Technical Summary

Problems solved by technology

These existing technologies can accurately detect and calibrate certain optical characteristic parameters of the wave plate, but there are several shortcomings in the following aspects: (1) the existing technology can only characterize one or two characteristic parameters of the wave plate , such as phase retardation or fast-axis azimuth, it is difficult to conduct a comprehensive detection and characterization of the wave plate; (2) Some techniques usually only give the parameters of a certain wavelength point of the wave plate, and then use the dispersion equation of the material to calculate It is also difficult to directly detect the spectral parameters of the wave plate in one measurement even if the parameter values ​​of other wavelengths are obtained, or the spectral data of the wave plate is given by scanning the wavelength; (3) Some technologies have high detection accuracy, such as laser frequency splitting The current national standard for wave plate phase delay detection is based on this method), but the detection process and data processing are relatively complicated, and the technical requirements for operators are relatively high

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