01-12-2009, 07:26 PM
ABSTRACT
The Virtual Retinal Display„¢ (VRD„¢) technology also known as a retinal scan display (RSD) or retinal projector is a new display technology being developed at Microvision Inc. The displayed image is scanned onto the viewer™s retina using low-power red, green, and blue light sources. Microvision™s proprietary miniaturized scanner designs make VRD system very well suited for head-mounted displays. In this paper we discuss some of the advantages of the VRD technology, various ocular designs for HMD and other applications, and details of constructing a system MTF budget for laser scanning systems that includes electronics, modulators, scanners, and optics , VRDs can give the user the illusion of viewing a typical screen-sized display hovering in the air several feet away. In principle the technology can provide full-color, high-resolution dynamic displays
normally VRD unit consists of 4 modules; drive electronics to break down an incoming source image into an information stream, a light source made up of laser(s) or LED(s), a scanner bank made up of horizontal and vertical scanners, and a lens to expand the image that projects through the scanners. As in a television, the scanners rapidly oscillate left-to-right or down-to-up, selectively permitting colors through in precise configurations that produce a high-resolution 2mm x 2mm field of pixels. Then a lens acting as an expander boosts the size of the image to something like 18mm x 18mm, allowing for a larger and more natural image. The pixel field is then projected onto the eye, where the eye's lens focuses the image onto the retina. Aside from tapping into the optic nerve itself, there may be no more effective way to display an image
read more
http://en.wikipediawiki/Virtual_retinal_display
http://swatijaininstetechno/VIRTUAL%20RETINAL%20SYSTEM.doc
