Method and apparatus for preventing keystone distortion and equalizing luminance

摘要

A method and apparatus are provided for preventing keystone distortion and to equalize uneven luminance effects in a projected image. A projected image (750a) is produced by projecting light from a light source (102) through a deformed image (700a) rendered on a display device (110) (e.g., an LCD panel) and onto a viewing screen or surface (130) at a non-perpendicular angle. An original image (700) received for projection is deformed in proportion to the projection angle to generate the deformed image (700a), which is projected to yield the projected image (750a) having proportions closely matching the original image (700). Luminance intensity across the display image (1822) may be adjusted by calculating (2402,2410) an attenuation factor and adjusting the luminance intensity of at least one of the plurality of lines of pixels of the original image in proportion to its initial intensity and/or the position of that at least one line of pixels.