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1.
Appl Opt ; 59(22): G33-G40, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32749314

RESUMO

We calibrate and test a division-of-focal-plane red-green-blue (RGB) full-Stokes imaging polarimeter in a variety of indoor and outdoor environments. The polarimeter, acting as a polarization camera, utilizes a low dispersion microretarder array on top of a sensor with Bayer filters and wire-grid linear polarizers. We also present the design and fabrication of the microretarder array and the assembly of the camera and validate the performance of the camera by taking multiple RGB full-Stokes images and videos. Our camera has a small form factor due to its single-sensor design and the unique capability to measure the intensity, color, and polarization of an optical field in a single shot.

2.
Opt Express ; 26(14): 18279-18291, 2018 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-30114009

RESUMO

A snapshot multi-wavelength interference microscope is proposed for high-speed measurement of large vertical range discontinuous microstructures and surface roughness. A polarization CMOS camera with a linear micro-polarizer array and Bayer filter accomplishes snapshot multi-wavelength phase-shifting measurement. Four interferograms with 𝜋/2 phase shift are captured at each wavelength for phase measurement, the 2𝜋 ambiguities are removed by using two or three wavelengths.

3.
Opt Express ; 26(4): 4192-4193, 2018 02 19.
Artigo em Inglês | MEDLINE | ID: mdl-29475271

RESUMO

We correct two figures showing the micro-polarizer arrangement on the RGB full-Stokes camera.

4.
Opt Express ; 23(4): 4357-68, 2015 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-25836472

RESUMO

This paper presents a polarization microscope using an infrared (IR) full-Stokes imaging polarimeter. The IR polarimeter utilizes an optimized interference-based micropolarizer design, and provides full-Stokes images with resolution of 1608 × 1208 at 35 frames/second. The device fabrication, instrument calibration, performance evaluation, and measurement results are presented. The measurement error of the imaging polarimeter is less than 3.5%, and the standard deviations are less than 2%.

5.
Opt Express ; 22(3): 3063-74, 2014 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-24663597

RESUMO

In this paper, a full-Stokes imaging polarimeter operating at 580 nm using an array of elliptical polarizers is presented. The division-of-focal-plane polarimeter utilizes a set of four optimized measurements which represent a regular tetrahedron inscribed in the Poincaré sphere. Results from the device fabrication, instrument calibration and characterization are presented. The performance of the optimized full Stokes polarimeter, as defined by size of the standard deviation of the degree of circular polarization, is found to be approximately five times better than the performance of the simple full-Stokes polarimeter.

6.
Opt Express ; 20(25): 27393-409, 2012 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-23262690

RESUMO

A division-of-focal-plane polarimeter based on a dichroic dye and liquid crystal polymer guest-host system is presented. Two Stokes polarimeters are demonstrated: a linear Stokes and the first ever Full-Stokes division-of-focal-plane polarimeter. The fabrication, packaging, and characterization of the systems are presented. Finally, optimized polarimeter designs are discussed for future works.


Assuntos
Modelos Teóricos , Polímeros , Refratometria/instrumentação , Refratometria/métodos , Compostos de Boro/química , Calibragem , Desenho de Equipamento , Interpretação de Imagem Assistida por Computador/instrumentação , Interpretação de Imagem Assistida por Computador/métodos , Silicatos/química
7.
Opt Lett ; 36(16): 3269-71, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21847230

RESUMO

A vibration-insensitive interferometer is described to measure the thickness, refraction index and surface profile of thin-film stack at normal incidence. By satisfying the continuous boundary conditions of electric and magnetic fields at interfaces in a multilayer film stack, the reflection coefficient phase of the thin-film stack can be distinguished from the phase of spatial path difference, thus thickness and refraction index can be extracted. The experiment results showed that the measurement precision is significantly increased after the phase analysis was added into the reflectance analysis.

8.
Biomed Opt Express ; 10(4): 1638-1648, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-31061760

RESUMO

We introduce a snapshot multi-wavelength quantitative polarization and phase microscope (MQPPM) for measuring spectral dependent quantitative polarization and phase information. The system uniquely integrates a polarized light microscope and a snap-shot quantitative phase microscope in a single system, utilizing a novel full-Stokes camera operating in the red, green, and blue (RGB) spectrum. The linear retardance and fast axis orientation of a birefringent sample can be measured simultaneously in the visible spectra. Both theoretical analysis and experiments have been performed to demonstrate the capability of the proposed microscope. Data from liquid crystal and different biological samples are presented. We believe that MQPPM will be a useful tool in measuring quantitative polarization and phase information of live cells.

9.
Appl Opt ; 44(32): 6861-8, 2005 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-16294959

RESUMO

Recent technological innovations have enabled the development of a new class of dynamic (vibration-insensitive) interferometer based on a CCD pixel-level phase-shifting approach. We present theoretical and experimental results for an interferometer based on this pixelated phase-shifting technique. Analyses of component errors and instrument functionality are presented. We show that the majority of error sources cause relatively small magnitude peak-to-valley errors in measurement of the order of 0.002-0.005lambda. These errors are largely mitigated by high-rate data acquisition and consequent data averaging.

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