投影機核心技術下.ppt

投影機之核心技術 Core Tech of Projector Part II 唐逸中 工研院光電所 民國89年8月4號 TEL:(03)5918394 E-mail:h880073@itri.org.tw 內容綱要 Further Vision for Projection Display Further projector will focus on high brightness high lumen throughput high efficiency and high collective efficiency high lumen output How can I optimize it ? Etendue puts the ideal case into practice. Why is etendue so magic? Recently more and more paper emphasize etendue making use in collection illumination and light efficiency. Etendue is the same as entropy (the 2th law of thermodynamic) so is better than energy consideration (the 1th law of thermodynamic ) Watt , lumen ------------ 1th law Etendue ------------ 2th law History of Etendue Original : 1996 Philips Lab. Paper : Define Etendue Author : Brennesholtz Continuous : 1997 Philips Lab. Conference Notes Describe the etendue generally 1998 Welch Allyn Inc. Paper Use efficiency concept to explain etendue 1997-1999 Welch Allyn Inc. publish some technical report 1998 There is a bible “ Projection Displays” Present : SID 99 Philips Lab. (H. Monch) Fusion lighting Inc. (K. Kipling ) Why Do We Use Etendue? The key characteristic for projector is : Luminous flux The luminous flux depends on some factors : lamp lumen throughput (Arc gap) reflector collection efficiency projector architecture light valve aperture ratio projection lens Lamp/reflector collection is difficult to make accurately Etendue evaluates system performance What is Etendue? Define the etendue : Etendue Limited Systems Which better is etendue high or low? Optical beam low etendue( Ebeam) Light valve high etendue ( Evalve) If Ebeam Evalve not etendue limited All the light can be used. If Ebeam Evalve etendue limited All the light can’t be used. An etendue limited system is limited by high cost item such as the LV and projection lens. Trapezoid Rod Function Etendue