Research On Color Waveguide Display

With the development of technology,helmet-mounted display(HMD),a revolutionary display technique initially used for military,has been widely used in many fields.Compared with the traditional HMD technology,the waveguide holographic HMD technology shows many advantages in lightweight and small size.At present,color holographic waveguide display low brightness due to immature technologies.To improve luminance,a color holographic waveguide composed of double-faced multiplexing grating with slanted angle deviation and another two systems based on double-faced or double-layer multiplexing grating with wavelength deviation are designed respectively.Firstly,the principles of three structures are described respectively,and then effects of in-coupler gratings on the optical characteristics of the waveguide display system are analyzed.Finally,the display performances of these different structure are analyzed.In this thesis,structures of red,green and,blue double-faced monochromatic grating with slanted angle deviation are optimized,respectively.Compared with the traditional one-side grating,the increment of total luminance coupling efficiency of red,green,green is 16.1%,10.9% and 6.1%,respectively.Accordingly,the color holographic waveguide display system based on double-faced gratings with slanted angle deviation is proposed.The simulation results show that the stray light and color crosstalk of the system is suppressed effectively.The system obtains the same color gamut as the traditional waveguide display system.Finally,we propose a novel holographic waveguide display system based on double-faced multiplexing gratings with wavelength deviated.The results show that the performance of the system is similar to that with slanted angle deviation.In order to improve the utilization of light,a novel holographic waveguide display system composed of double-layer multiplexing gratings on one side is proposed based on the doublefaced gratings structure we have proposed.Double-layer multiplexing gratings are used as both in-coupler and out-coupler.Herein the double-layer multiplexing structure can be either slanted angle deviation or wavelength deviation.The simulation results show that the color system can further improve the display brightness compared to the double-faced gratings structure,while the stray light and color crosstalk can also be effectively suppressed.