US Patent 7446822 High-resolution image projection

A lightweight, compact image projection module, especially for mounting in a housing having a light-transmissive window, is operative for causing selected pixels in a raster pattern to be illuminated to produce an image of high resolution of VGA quality in monochrome, color or gray scale. Pixel size is controlled as a function of distance of the image from the module to control image resolution and allow the image to remain sharp and clear over an extended range of distances from the module.