Polarized imaging characteristics of the twisted nematic liquid-crystal structure leading to an electrically regulated polarimetric camera prototype

Abstract A polarimetric camera prototype is proposed, which is mainly based on coupling a twisted nematic liquid-crystal (LC) material driven electrically with an arrayed CMOS sensor to rapidly select and establish the required polarization state of the imaging light field. The mechanism for electrically manipulating polarized rotation by a thick functional LC film of more than 20 μ m, which clearly presents a featured signal voltage window effect based on electrically switching and further regulating between the polarized sensitive and non-sensitive modes, is analyzed carefully. The key controllable parameters including a degree of polarization and a set of azimuth of polarization outfrom the imaging prototype can be employed as the prior clues for effectively actuating and tuning the polarized LC chip. The operation for remarkably enhancing the target detection and recognition efficiency according to the segmented profiles, edge details or featured symbols of selected objects will lead to an obvious boost for efficiently capturing and identifying targets of interest. The relationship between the polarization state or re-oriented rotating angle of the imaging micro-beams and the signal voltage loaded over the LC chip is investigated through fine-tuning the root-mean-square voltage based on an ordered variance of the polarization azimuth in the range from the initial 0° to the final 90°. The comparative imaging measurements demonstrate the effectiveness of the electrically regulated polarimetric camera prototype, highlighting a possible future development by upgrading the polarized photosensitive array.