臺灣博碩士論文加值系統

隨著智慧型手機需求的與日俱增，微型投影技術已逐漸成為智慧型手機的基本配備之一。觀察現今所有的微投影光源，基本上大多使用RGB-based LED 來做為發光源進而混合生成為投影用之白光光源，主要之原因在於LED 具備有壽命長、消耗功率低、體積小等優點。此外，目前相當熱門的可見光通訊技術在室內短距離通訊傳輸上的應用，其所使用的光發射器也是以LED 為主要發光源。
但目前可見光通訊技術應用於室內短距離通訊上所使用的LED 仍是以使用藍光LED 激發黃色螢光粉的LED 為主，這類光源與目前投影機所使用之RGB-based LED 光源不同，雖其價格較投影用之RGB-based LED 便宜，但因藍光LED 激發黃色螢光粉將會使得LED 頻寬受限於螢光粉的轉換時間，所以若使用RGB-based LEDs，將不會有這些問題產生，且LED 的傳輸頻寬也將能有效的增加幾倍。因此本論文嘗試將微投影架構與短距離可見光通訊技術做結合，首先探討現今微投影技術的分類以及原理，接著嘗試進行微投影機之設計。在微投影機的設計中，首先使用光學模擬軟體Zemax 及Fred 進行微投影機的照明與成像系統之模擬設計與性能分析，來達到透鏡組橫向色差與光斑皆小於一個像素、畸變小於2%及調變轉移方程式各場角的光在43 lp/mm 上皆大於50%的狀態；且照明系統在成像元件上為均勻光，而在投影平面上，照度可以達到200 lux。初步所模擬設計之微投影系統其大小約為8×6×3.2 cm3，相當於掌上型之行動裝置大小。而在使用微投影系統專用之RGB-based LED 光源來進行短距離可見光通訊之實現上，本論文透過等化器之設計來改善RGB-based LED 之傳輸頻寬。經由設計與實作後，量測結果顯示紅光頻寬已從原始的6.2 MHz 提升至25.2 MHz、綠光頻寬從原始的8.6 MHz 提升至27.8 MHz 而藍光頻寬則從原始的9.3 MHz 提升至26.2 MHz。為進行數據資料傳輸測試，本論文在0.5 公尺的傳輸距離下，使用OOK 調變方式進行訊號傳輸測試。量測結果顯示RGB-based LED 在誤碼率為10-3 的條件下，總傳輸速率可以達到300Mb/s 以上。

With the increasing demands on smart mobile phone device in modern society,
micro-projection is widely expected to become an essential module in the future smart mobile phone device. In most of current micro-projectors, RGB-based LED has been widely used as the major light sources to perform the color mixture of white light,since using RGB-based LEDs as the light source have the advantages of longevity,low power consumption, and small size compared with other conventional light sources. Moreover, white light LEDs have also been used as the major light source of optical transmitter in the recent developed visible light communication system (VLC)for short-range data transmission. However, phosphor-based white light LEDs are currently used in most of VLC system as they are cheaper than RGB-based LEDs. Nevertheless, the modulation bandwidth of this kind of phosphor-based white light LED has restricted by its phosphor conversion time, and therefore RGB-based LEDs are promising to offer a higher modulation bandwidth as they don't have this problem. In this research, a VLC system based on micro-projection architecture for short-range data transmission is investigated. The research, started with the review of micro-projection technologies and their operation principle. A reflective Ferroelectric
Liquid Crystal on Silicon (FLCoS)-based micro-projection architecture composed of an illumination system and an image system has been designed and simulated by
optical simulation tools (Zemax and Fred). From the performance evaluation, the
image lens system achieve a lateral color and spot size less than one pixel, distortion less than 2%, and a MTF (modulation transfer function) in every field at 43 lp/mm is greater than 50%. Moreover, the simulation results have also shown that the illumination performance is uniform and can provide more than 200 lux based on a projection size of 8×6×3.2 cm3. In order to implement an experimental VLC system based on micro-projection architecture, RGB-based LED for micro-projection
application was utilized as the light source to perform data transmission in our
research works. The equalization technique was also used to improve the modulation bandwidth of RGB-based LED. From the experimental measurements, the results have shown that modulation bandwidth of RGB-based LED after equalization design can be improved from 6.2 MHz to 25.2 MHz (for Red-LED), from 8.6 MHz to 27.8 MHz (for Green-LED), and from 9.3 MHz to 26.2 MHz (for Blue-LED). Finally, a digital data transmission test using on-off keying (OOK) modulation scheme was
performed in this RGB-based LED visible light communication link at a distance of 0.5m. The results demonstrated that a high-speed aggregative data transmission rate over 300Mb/s can be achieved at a bit error rate (BER) of 10-3.

摘要............................................................. I
Abstract.........................................................II
誌謝............................................................. IV
目錄............................................................. V
圖表索引...........................................................VII
第一章 緒論........................................... 1
1.1 前言..............................................1
1.2 研究動機...........................................2
1.3 論文架構...........................................2
第二章 結合行動顯示裝置之可見光通訊系統 .....................3
2.1 微投影顯示裝置.......................................3
2.1.1 微投影機主要光源比較................................3
2.1.2 微投影機成像元件之比較..............................7
2.2 可見光通訊系統.......................................11
2.3 行動顯示光源用於可見光通訊之特性分析.....................15
第三章 LED 微投影機設計模擬與分析 ........................ 21
3.1 照明系統設計........................................21
3.1.1 微投影機照明系統分類................................21
3.1.2 光度學...........................................23
3.1.3 照明系統模擬設計與性能分析...........................25
3.2 成像系統設計........................................32
3.2.1 成像品質評估......................................32
3.2.2 成像系統設計與性能分析..............................35
3.3 微投影機性能模擬與結果分析............................40
第四章 可見光通訊光源量測及分析 .......................... 44
4.1 LED 積分球量測與分析.................................44
4.2 LED 原始頻寬量測與分析...............................45
4.2.1 上升下降時間量測推估出頻寬...........................46
4.2.2 3 dB 頻寬量測點頻測試法.............................47
4.3 LED 頻寬改善方法.....................................50
第五章 可見光通訊系統鏈結 ................................ 55
VI
5.1 等化器設計..........................................55
5.2 頻寬改善............................................56
5.3 資料傳輸測試.........................................58
5.4 總結...............................................65
第六章 結論與未來展望.................................... 66
6.1 總結 ..............................................66
6.2 未來展望 ...........................................67
參考文獻............................................... 68

Christian Pohlmann, “Visible light communication,” Seminar
Kommunikationsstandards in der Medizintechnik, 2010.
[2] Sridhar Rajagopal, Richard D. Roberts, “IEEE 802.15.7 visible light
communication: modulation schemes and dimming support,” IEEE
Communications Magazine, March, 2012.
[3] http://www.ted.com/talks/harald_haas_wireless_data_from_every_light_bulb
[4] http://www.samsung.com/global/microsite/galaxybeam/
[5] 中村修二(Shuji Nakamura)，黎奧丹(Michael Riordan), “綠光雷射即將現身”，
科學人雜誌，2009年5月。
[6] CIE, in Proc. Commission Int. l’Eclairage, 1924.
[7] Edward Buckley, “Laser wavelength choices for pico-projector applications,”
Journal of Display Technology, vol. 7, no. 7, July, 2011.
[8] Kishore V. Chellappan, Erdem Erden, “Laser-based displays: a review,” Applied
Optics ,vol. 49, no. 25 , September 1, 2010.
[9] Zhaomin Tong, Xuyuan Chen, “Compound speckle characterization method and
reduction by optical design,” Journal of Display Technology, vol. 8, no. 3, March,
2012.
[10] Byong-Deok Choi, “Image quality enhancement in AMOLED microdisplay for
mobile projectors, ” IEEE Transactions on Consumer Electronics, vol. 57, no. 2,
May, 2011.
[11] 陳金鑫，黃孝文，夢幻顯示器OLED材料與元件，五南圖書出版社，2012年
二月。
[12] http://www.ti.com.tw/articles/detail.asp?sno=18
[13] Peter F. Van Kessel, Larry J. Hornbeck, “A MEMS-based projection display,”
69

Proceedings of the IEEE, vol. 86, no. 8, August, 1998.
[14] Brennesholtz, Matthew S, Projection displays, U.K., J. Wiley and Sons, 2008.
[15] http://highscope.ch.ntu.edu.tw/wordpress/?p=1613
[16] Lueder, Ernst, Liquid crystal displays: addressing schemes and electro-optical
effects, New York, Wiley, 2001.
[17] http://www.itrc.narl.org.tw/Publication/Newsletter/no68/p10.php
[18] Lan Underwood, “A review of microdisplay technologies,” The University of
Edinburgh, 2000.
[19] Joseph M. Kahn, “Wireless infrared communications,” Proceedings of the IEEE,
vol. 85, no. 2, February, 1997.
[20] http://arstechnica.com/science/2009/02/yes-virgina-there-is-a-magenta/
[21] Toshihiko Komine, Masao Nakagawa, “Fundamental analysis for visible-light
communication system using LED lights,” IEEE Transactions on Consumer
Electronics, vol. 50, no. 1, February 2004.
[22] Xiaohan Liu, “Basic study on indoor location estimation using visible light
communication platform,” 30th Annual International IEEE EMBS Conference
Vancouver, British Columbia, Canada, August 20-24, 2008.
[23] Jonathan J. D. McKendry, David Massoubre, “Visible-light communications
using a CMOS-controlled Micro-Light-Emitting-Diode array,” Journal of
Lightwave Technology, vol. 30, no. 1, January 1, 2012.
[24] G. Cossu, A. M. Khalid, “3.4 Gbit/s visible optical wireless transmission based
on RGB LED,” Optics Express, vol. 20, no. 26, December 10, 2012.
[25] Ahmad Helmi Azhar, Tuan-Anh Tran, Dominic O’Brien, “A gigabit/s indoor
wireless transmission using MIMO-OFDM visible-light communications,” IEEE
Photonics Technology Letters, vol. 25, no. 2, January 15, 2013.
[26] Hoa Le Minh, Dominic O’Brien, “High-speed visible light communications
70

using multiple-resonant equalization,” IEEE Photonics Technology Letters, vol.
20, no. 14, July 15, 2008.
[27] Hoa Le Minh, Dominic O’Brien, “100-Mb/s NRZ visible light communications
using a post equalized white LED,” IEEE Photonics Technology Letters, vol. 21,
no. 15, August 1, 2009.
[28] A. Burton, H. Le Minh, Z. Ghassemlooy, “Smart receiver for visible light
communications: design and analysis,” 8th IEEE, IET International Symposium
on Communication Systems, Networks and Digital Signal Processing, 2012.
[29] E. Fred Schubert, Light-emitting diodes, 2nd ed, Cambridge University Press,
2006.
[30] F.K. Yam, Z. Hassan, “Innovative advances in LED technology,”
Microelectronics Journal 36, 2005.
[31] Paul Anthony Haigh, Zabih Ghassemlooy, “2.7 Mb/s with a 93-kHz white
organic light emitting diode and real time ANN equalizer,” IEEE Photonics
Technology Letters, vol. 25, no. 17, September 1, 2013.
[32] Optical performance optimisation, Forth Dimension Displays, August 14, 2008.
[33] PhlatLight™ PT54, Product summary data sheet, Luminus devices Inc, 2011.
[34] 蔡家壽，“高功率穿透式液晶顯示投影機之設計”，國立台灣科技大學碩士論
文，2011年六月。
[35] E. H. Stupp and M. S. Brennesholtz, Projection display, England, Wiley,1999.
[36] 陳昱達，“新型投影機光源之研究”，國立中央大學碩士論文，2008年七月。
[37] Michael D. Robinson, Gary Sharp, Polarization engineering for LCD projection,
Wiley, May 2005.
[38] Eugene Hect, Optics, 4th ed, Addison Wesley, 2001.
[39] 李介仁，“輕薄短小的DLP變焦投影鏡頭之設計探討”，國立中央大學碩士論
文，2002年五月。
71

[40] Hoa Le Minh, Dominic O’Brien, “80 Mbit/s visible light communications using
pre-equalized white LED,” Brussels, Belgium, ECOC 2008, September 21-25,
2008.
[41] 光電科技工業協進會，“投影光學元件”，2004年八月。