ABSTRACT
We propose an autostereoscopic display system that ensures full resolution for multiple users by directional backlight and eye tracking technology. The steerable beam formed by directional backlight can be regarded as the result of sparsely sampling the light field in space. Therefore, we intuitively propose an optimization algorithm based on the characterization for the state of the steerable beams, which is computed in matrix form using the plenoptic function. This optimization algorithm aims to optimize the exit pupil quality and ultimately enhancing the viewing experience of stereoscopic display. Numerical simulations are conducted and the improvement in exit pupil quality achieved by the optimization scheme is verified. Furthermore, a prototype of the stereoscopic display that employs dual-lenticular lens sheets for the directional backlight has been constructed using the optimized optical parameters. It provides 9 independent exit pupils at the optimal viewing distance of 400 mm, with an exit pupil resolution of 1/30. The field of view is ±16.7°, the viewing distance range is 380 mm to 440 mm. At the optimal viewing distance 400 mm, the average crosstalk of the system is 3%, and the dynamic brightness uniformity across the entire viewing plane reaches 85%. The brightness uniformity of the display at each exit pupil is higher than 88%.
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.