The invention discloses an LCOS optical illumination
system for an AR-HUD projection unit, and belongs to the field of photoelectric illumination and display technologies. The
system comprises an illumination
light source, a collimating lens, a fly-
eye lens, an optical diffuser, a
wavelength selective light combination element, a polarized light conversion device, a
relay lens, a PBS
prism and an LCOS display
chip. The illumination
light source is a three-color LED
light source and is composed of a
red light LED, a
green light LED and a
blue light LED. After red primary light, green primary light and blue primary light are collimated by the collimation
system, the light parallelism is optimized, the
collimated light sequentially passes through the light
diffusion element to optimize the
light field uniformity and the fly-
eye lens to eliminate the non-uniform illumination, then is unified into a single
linear polarization state by the polarized light converter, is shaped by the
relay system and keeps the
light beam transmission quality, and finally is transmitted to the light source. And polarization state separation and light combination are realized through the PBS
prism, and finally, the light is accurately coupled to the LCOS display
chip, so that high-efficiency polarization state matching and
imaging quality optimization are completed. According to the HUD-PGU system, the illumination brightness of the whole system is improved, the color reducibility of the system is improved, the illumination uniformity of system imaging is improved, the
light energy utilization rate of the system is improved, meanwhile, the size of the HUD-PGU is reduced, and the manufacturing cost is reduced.