| 摘要 |
An optical device includes a source such as an LED, a microdisplay such as an LCoS panel, and a relay prism between them. The relay prism has input and output surfaces arranged to tilt the system optical axis, At least one of those surfaces is a cylindrical surface that, along with the tilt, changes the aspect ratio AR of light emanating from the source to the AR of the microdisplay without clipping. The cylindrical surface defines parallel cross sections, each of which define a center of curvature that together define a line that crosses the system optical axis or an extension thereof. This preserves total luminance since clipping is not used to change the AR, and provides substantially uniform illumination across the new AR. Also detailed is a method and further details of an exemplary pocket sized optical engine for which the output of the microdisplay is directed to a projection lens. |
