An LTPS Ambient Light Sensor System with Sensitivity Correction Methods in LCD

• NAKAMURA Takashi

  Japan Display

• TADA Masahiro

  Japan Display

• KIMURA Hiroyuki

  Japan Display

抄録

An integrated ambient light sensor (ALS) system in low-temperature polycrystalline silicon (LTPS) thin-film-transistor liquid-crystal-displays (TFT-LCDs) is proposed and prototyped in this study. It is designed as a 4-bit (16-step-grayscale) ALS and includes a noise subtraction circuit, a comparator as an analog-to-digital converter (ADC), 4-bit counters, and a parallel-to-serial converter. LTPS lateral p-i-n diodes with a long i-region are employed as photodetectors in the system. An LSI source driver is mounted on the LCD panel with a sensor control block which provides programmable clocks and reference voltages to the ALS circuit on the glass substrate for sensitivity tuning. The reliability tests were conducted for 300 hours with 30000 lux illumination at 70 ^°C and at -20 ^°C. The observed deviations of the ALS values for dark, 1000 lux, and 10000 lux were within ±1.

収録刊行物

• IEICE Transactions on Electronics

  IEICE Transactions on Electronics E102.C (7), 558-564, 2019-07-01

  一般社団法人 電子情報通信学会

キーワード

• LTPS
• ambient light sensor
• p-i-n diode
• optical sensor

詳細情報

• CRID: 1390845713079646464
• NII論文ID: 130007671359
• DOI: 10.1587/transele.2018ctp0004
• ISSN: 17451353
• ISSN: 09168524
• Web Site: https://www.jstage.jst.go.jp/article/transele/E102.C/7/E102.C_2018CTP0004/_pdf
• 本文言語コード: en
• データソース種別:
  • JaLC
  • Crossref
  • CiNii Articles
• 抄録ライセンスフラグ: 使用不可