Producing a projection system with a single full-color LCD, which requires only one optical train instead of three, greatly reduces system cost, weight, and size but further reduces image brightness while increasing pixel visibility due to the additional appearance of individual red, green, and blue sub-pixels. At Projectavision, we have devised various optical techniques to reduce these drawbacks. This paper reports on several of these techniques and presents a computer analysis to quantify the effectiveness and limitations of some of this optical technology. The paper reports on `Depixelization' utilizing micro-lens arrays, as well as prism wedges and spatial filtering. Quantification analysis demonstrates a 90% reduction in pixel visibility due to depixelization as well as 60% reduction in the brightness difference between dead pixels and neighboring functioning pixels. This results in a greater tolerance for such dead pixels, while retaining resolution with very minimal loss of MTF. This paper also reports on some of the optical designs we devised for `brightness enhancement' to reduce light loss in the projection systems. Additionally, the paper reports on both front- and rear-screen projection prototypes and 3D video projection.
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