背投影顯示器對比提升之改善

A study of contrast improvement on LCoS Projection display

陳宏緯(Hun-wei Chen)

指導教授 ： 章明

中原大學/工學院/機械工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400195

摘要

I
一般的液晶背投影顯示器LCoS 投影系統，都是使用高壓汞燈做為投影光源，汞燈的特性在綠光的光能量相較於紅光、藍光強，導致混合成白光時偏綠。為了改善此狀況，一般皆利用調整LCoS 上的電壓，來降低綠光的能量，使得R、G、B 的能量匹配，得到所要的色溫、標準的白場及較高的對比度。本研究則提出一個新的架構用以改LCoS 投影顯示器的效能，主要構想係於光學引擎內的光學元件著手，透過使用Econtrast filter 來降低綠光，而得到較白的白場；本研究成果已實際用於LCoS 投影顯示器的光學系統內，相較於調整顯示器上電壓的方法，其實際白場與暗場之對比量測數據由821:1 提升至1008:1，提升幅度高達22.8%。
關鍵字：液晶背投影顯示器(LCoS)、對比度

關鍵字

對比度 ； 液晶背投影顯示器

並列摘要

ABSTRACT
A high-pressured mercury lamp is usually adopted to be the lightsource of the projection in a LCoS projection system. When comparedwith red or blue lights, the green light’s luminous energy within themercury lamp is more intense, causing the white light that is formed by a mix of the primary RGB colors to tend to shift towards green.
In order to improve this situation, generally the voltage within the LCoS is adjusted to reduce the energy of the green light, so that the energy distribution levels of the primary colors RGB is balanced,achieving the standard color emperature, a brighter white-valve and a higher contrast.
This research proposes a new overhead construction to improve the potency of the LCoS projection monitor. The main idea begins with the
optics of the optical engine. Through using an Encontrast filter to reduce the green light, a whiter valve is able to be obtained. It has been actively applied to the LCoS projection monitor optical system. When compared with the voltage method in an adjusting display, the contrast data of the white and dark valve increased from 821:1 to 1008:1 and the promotion scope reached as high as 22.8%.
Keyword:LCoS,Contrast

並列關鍵字

Contrast ； LCoS

參考文獻

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