Mueller polarimetric imaging system with liquid crystals

Abstract

We present a new polarimetric imaging system based on liquid-crystal modulators, a spectrally filtered white-light source, and a CCD camera. The whole Mueller matrix image of the sample is measured in approximately 5 s in the transmission mode. The instrument design, together with an original and easy-to-operate calibration procedure, provides high accuracy over a wide spectral range (500-700 nm). This accuracy has been assessed by measurement of a linear polarizer at different orientations and a thick wedged quartz plate as an example of a partially depolarized retarder. Polarimetric images of a stained hepatic biopsy with significant fibrosis have been taken at several wavelengths. The optical properties of Picrosirius Red stained collagen (diattenuation, retardance, and polarizance) have been measured independently from each other between 500 and 700 nm.

Turbid medium polarimetry in biomedical imaging and diagnosis

“…The Mueller matrix polarimeters based on liquid crystal variable retarders have the added advantage of enabling large area polarimetry imaging with high sensitivity and precision. For details of the designing and working principles of these polarimeters, the reader is referred to references [26,38,43,44]. Another important development in Mueller matrix polarimetry is the Snapshot Mueller matrix polarimeter [45].…”

“…It should be mentioned here that in each of the two polarization state imaging schemes (linear and circular), various sub-imaging strategies have also been investigated [44,45]. These include the co-polarized imaging, the polarization difference (or subtraction) imaging and the degree of polarization (DOP) imaging.…”

Mueller matrix interpolation in polarization optics

“…The measurement of the Mueller matrix entries attached to each pixel in an image is named Mueller imaging. The development of optical devices and systems [1], calibration procedures [2] and measurement inversion methods [3] [4] produced Mueller imaging systems with low noise measurement where the physical constraints on Mueller matrices are taken into account. These works contributed to popularize this imaging approach and examples of Mueller matrix imaging can be found for characterizing biological objects [5] or scattering media [6], with applications in dermatology [7], ophthalmology [8] or physics [9][10] for instance.…”

Single-pixel polarimetric imaging

“…The use of PI has spread into a great variety of optical applications, including scene analysis and target detection [2], polarization-sensitive microscopy [3], and segmentation of rough surfaces [4]. In the field of biomedical imaging, polarimetric techniques have been used for enhanced visualization of biological samples at different depths [5] as well as in vivo detection and diagnosis of cancerous tumors in tissues [6,7]. PI can be also combined with optical coherence tomography [8], ophthalmic adaptive optics [9], and hyperspectral imaging [10,11].…”

“…The high dynamic range (up to 70 dB), broad wavelength range, and accuracy on the Poincaré sphere of such commercial single-pixel polarimeters are readily transferred to PI. This fact opens a wide spectrum of application possibilities and eliminates the demand of sophisticated methods to optimize the design of current expensive polarimetric cameras based on pixelated sensors [7,15]. The CS algorithm is at the heart of our optical design, where the time-multiplexed acquisition process is brought off by a programmable spatial light modulator (SLM).…”