液晶投影機的色彩均勻性與光電特性

Abstract

本論文利用液晶連續體理論、廣義瓊斯矩陣法與色度學來分析液晶投 影機的色彩均勻性與光電特性。在此，提出了一套方便且具彈性的液晶投 影機模擬方法，可幫助液晶投影系統的設計以及規格的決定。利用這套模 擬方法，本論文探討了不同鍍膜設計、照明光強度均勻性以及液晶板光電 特性三方面對色彩均勻性表現的效應。 為了使液晶投影機的色彩更加 均勻，本論文建議採用漸層鍍膜的雙色分光鏡方式，來補償不同入射角造 成的鍍膜分光頻譜漂移，可使得色彩表現更加飽和。除此之外，本論文的 分析結果也顯示不同照明光強度均勻性對液晶投影機色彩均勻性影響極大 ，這顯示設計液晶投影機時，色彩均勻性可經由改善光強度均勻性來達成 。至於液晶板引起的亮度不均勻效應，也利用液晶分子的數值模擬以及光 學穿透的計算得到數值上的結果。這可提供電子驅動方式及光學設計上的 依據，以使投影效果達到色彩均勻的目標。綜合以上，這種整體的分析對 於改善液晶投影機的色彩均勻性有很大幫助。 The chromatic uniformity and electro-optic propertiesof LC projector was analyzed based upon liquid crystaltheorem, extended jones matrix method and chromatics. Here, a convenient and flexible simulation tool for LCprojector was developed , which can greatly reduce thecomplicated process in design work and the determinationof specification in LC projector. Using this tool, theeffect of different dichroic coating design, uniformityof illumination and electro-optic properties of LCpanels were investigated. In order to achieve higher chromatic uniformity of LCprojector, gradation coating on dichroic mirrors issuggested to compensate the shift of dichroic spectrumdue to the change of light incident angles, and moresaturated color performance can be achieved. Moreover,the illuminating uniformity strongly affects chromaticuniformity of the display imagery. Thus chromaticuniformity can be improved by increasing illuminatinguniformity of LC projectors. Finally, the non-uniformtransmittance effect caused by LC panels was calculatednumerically by simulating LC molecular deformation andoptical transmittance. This result can be used to adjustchromatic uniformity of LC projector by proper drivingmethods or optical designing. The presented analyses arevery useful to improve the chromatic uniformity of LCprojectors.