Wavelength-multiplexed stereoscopic LC display using scanning backlight

Appl Opt. 2021 Mar 10;60(8):2331-2338. doi: 10.1364/AO.417280.

Abstract

A stereoscopic display system based on a wavelength-multiplexed and time-multiplexed technique is introduced. The system includes white LEDs, complementary multiband bandpass filters, 30 double-side-lit light guide bars, and a liquid crystal display panel, as well as a pair of complementary multiband bandpass filter glasses. The LEDs are divided into two groups, and each group is covered with a kind of complementary multiband bandpass filter. They can be controlled by the driving circuit and work in the scanning mode in synchronization with the liquid crystal display panel, as the liquid crystal display panel displaying the left and right images frame by frame. The backlight for the left and right images is sampled by complementary multiband bandpass filter1 and complementary multiband bandpass filter2, respectively, and can only pass through the corresponding glass lens, realizing channel separation. A prototype based on this principle was set up and experiments were carried out to evaluate the performance of the system. Double-side-lit backlight with light guide bars ensures the uniformity of the backlight while using fewer LEDs, and therefore reducing power consumption. Brightness through complementary multiband bandpass filter1 and complementary multiband bandpass filter2 is about 50.5 nits and 55.5 nits, respectively. It is demonstrated in our system that the scanning backlight with 30 light guide bars is capable of reducing cross talk to 2.2%. Furthermore, the resolution in the wavelength-multiplexed 3D mode is the same as the physical resolution of the liquid crystal display panel.