This Letter introduces a polarization phase-shifting Newton interferometer that can be utilized for plane optical surface measurements, a setup constructed to realize the interferometer, and the experimental results from the use of the setup. The results confirm not only the validity but also the feasibility of the interferometer.

A shearing interference microscope using a Savart prism as the shear plate is proposed for inspecting step-heights. Where the light beam propagates through the Savart prism and microscopic system to illuminate the sample, it then turns back to re-pass through the Savart prism and microscopic system to generate a shearing interference pattern on the camera. Two measurement modes, phase-shifting and phase-scanning, can be utilized to determine the depths of the step-heights on the sample. The first mode, which employs a narrowband source, is based on the five-step phase-shifting algorithm and has a measurement range of a quarter-wavelength. The second mode, which adopts a broadband source, is based on peak-intensity identification technology and has a measurement range up to a few micrometres. This paper is to introduce the configuration and measurement theory of this microscope, perform a setup used to implement it, and present the experimental results from the uses of the setup. The results not only verify the validity but also confirm the high measurement repeatability of the proposed microscope.

A phase-shifting shearing interference microscope (PSSIM) is introduced in this paper. It is constructed by placing a Savart shear prism between the objective and sample of a polarizing microscope with a rotatable analyzer as the phase-shifter, and it is capable of determining contour height variation and deformation strain using the principle of shearing interferometry. This paper not only interprets the measurement theory but also presents an experimental setup of the PSSIM. Moreover, this paper exhibits the results from the uses of the setup; the results demonstrate the validity and applicability of the PSSIM.

Due to high technology requirements for modern display devices such as flexible, high resolution, thinner and higher transmission of polarizations, non‐destructive testing methods for evaluating quality of thin film plate polarizers are in high demand. In this paper, a system which can be used to observe defects and inhomogeneity of these thin film plate polarizers such as wide grid polarizers and thin film coating polarizers is proposed. This system consists of a collimated backlight light source, an afocal system, a polarizer, a rotation stage and a CCD camera. The collimated backlight is used to produces a collimating beam to pass through a sample under test. The afocal system shrinks the size of light beam from sample to pass through the polarizer. Based on Malus’s law, intensity of each pixel of images on CCD camera varies with the angle between the transmission axes of sample and polarizer, which is controlled by the rotation stage. Uniformity of thin film plate polarizers can be defined as polarization extinction ratio. This paper is to introduce the configuration and measurement theory, perform a setup used to implement it and present the experimental results from the uses of the setup. The results not only verify the validity but also confirm the feasibility of the proposed systems.

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