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浏览/检索结果: 共3条，第1-3条 帮助 限定条件 内容类型：会议论文    专题：长春光学精密机械与物理研究所    第一署名单位    第一作者单位    通讯作者单位     已选(0)清除 条数/页：5101520253035404550556065707580859095100   排序方式：请选择作者升序作者降序题名升序题名降序发表日期升序发表日期降序提交时间升序提交时间降序 LED optical engine based on rectangular CPC for micro-projection display (EI CONFERENCE) 会议论文 4th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, November 19, 2008 - November 21, 2008, Chengdu, China Wang S.-Y.; Sun W.-J.; Bu W.-B.; Meng Z. 收藏  |  浏览/下载：11/0  |  提交时间：2013/03/25 With applications in digital display  consumer electronics  medicine  automotive lighting  traffic signals  and general illumination  the light-emitting diode (LED) is the world's most efficient light source being mass produced today[1]. However  high cost is the main factor restricting widespread application of LED lighting  and the packaging is the most expensive aspect of LED products. Light emitting diodes (LED) are regarded as the most important light sources in solid-state lighting for their advantages in energy efficiency  long life  vivid colors  high reliability  environmental protection  safety and multiple applications. However  application of LEDs in projection display exist many questions such as low illuminance uniformity and low energy efficiency by reason of luminescence distribution and constructure specificity for LED  the study on application of LED in the micro-projection display and projection display is reported[2-8]. Considering the question mensioned above the rectangular CPC(Compound Parabolic Concentrator) system with three-color LED is applied in the projection display. 2009 SPIE.   Study on chroma balance based on grating spectrometer for LED (EI CONFERENCE) 会议论文 Light-Emitting Diode Materials and Devices II, November 12, 2007 - November 14, 2007, Beijing, China Sun W.-J.; Wang S.-Y.; Yin Y.-Z.; Rong X.-W.; Meng Z. 收藏  |  浏览/下载：19/0  |  提交时间：2013/03/25 A standard white light compounding algorithm based on combination of choma coordinates acquisition system with computer working current control system is presented for three-color LED. The chroma coordinates acquisition system consist of grating spectrometer and integrating sphere. The computer adjust and control the working current of three-color LED  then achieved chroma coordinates error between the compounded white light and standard white light D65  until the chroma coordinates is less than the threshold beforehand set by this technique. The compounded white light meet the chroma error demanded that is able to be changed  at the same time the chroma coordinates acquisition system and the working current control system are eliminated. The proposed algorithm the offset of central wavelength and the change of chroma coordinates due to working current variety for LEDs. Experimental results show that the proposed algorithm achieved lesser chroma error uv=0.001 relative to standard white light D65  enhanced chroma uniformity of illumination field.   Design of an improved data signal timing for an amorphous silicon active-matrix organic LED display (EI CONFERENCE) 会议论文 ICO20: Display Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China Liao Y.-P.; Zhang Z.-W.; Shao X.-B.; Liu J.-E.; Guo-zhu F. U.; Jing H.; Qiu F.-B.; Kai M. A. 收藏  |  浏览/下载：12/0  |  提交时间：2013/03/25 The most critical issue in the design of an active matrix organic light emitting diode (AM-OLED) display pixel is the pixel to the pixel luminance uniformity. By substituting four-thin film transistor (TFT) pixel circuit for two-TFT pixel circuit  the luminous uniformity has great improved  but it requires more components than the two-TFT pixel circuit. There are some barriers needed to resolve to utilize hydrogenated amorphous silicon transistor to lit OLED  such as low field effect mobility  low output current and threshold voltage shift. In this article  a two-a-Si:H TFT pixel circuit was designed  which consisted of one named switching TFT and the other named driving TFT. The driving TFT gate line structure modified and a data signal timing improved were reported. The modified driving TFT can provide enough current about 30 microampere to lit OLED and the novel data signal timing can provide a constant current to OLED by restraining the driving TFT threshold voltage variation. In the novel data signal timing  the control signals to the driving TFT gate include a data signal and a reverse data signal. The signals alteration is performed either at a frame rate or at a line rate. By experiments  the driving TFT output current value is plotted as a function of the time in different reversed voltage value. When the magnitude of the positive data signal and the negative data signal is equal  the variety of Vth  is smallest  about 1.28V after a fixed stressing time of 1.33104min  which shows the novel data signal timing can improved the driving TFT output-input current stability.