20140125559 | OPTICAL DEVICE FOR VIRTUAL IMAGE DISPLAY WITH UNEQUAL FOCAL LENGTH AND HIGH MAGNIFICATION - An optical device for virtual image display with unequal focal length and high magnification, comprising an image display, an optically transparent material and a mirror; the optically transparent material being disposed at an oblique angle between the image display and the mirror, and, on the optically transparent material, the side opposite the image display being coated with a reverse anti-reflective film, the other side being coated with a polarizing film or successively with a polarizing film and a forward anti-reflective film; and the included angle between the mirror and the optically transparent material together with the deposition angle M of the reverse anti-reflective film being 90°. The present invention is an optical device structural design with a virtual image optical design including a birefringence function, providing a new design with innovative and improved optics. When magnifying a spatial and virtual image to an even greater extent, the image is larger and clearer, and the planarity of the image is greater, there is no distortion, and user requirements for a head mounted display in the HMD product market can be met. | 05-08-2014 |