发明申请
- 专利标题: LIGHT SOURCE FREQUENCY DETECTION CIRCUIT USING BIPOLAR TRANSISTOR
- 专利标题(中): 使用双极晶体管的光源频率检测电路
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申请号: US11942604申请日: 2007-11-19
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公开(公告)号: US20090128660A1公开(公告)日: 2009-05-21
- 发明人: Tiejun Dai , Sohei Manabe , Hongtao Yao , Jingzhou Zhang , Liping Deng
- 申请人: Tiejun Dai , Sohei Manabe , Hongtao Yao , Jingzhou Zhang , Liping Deng
- 申请人地址: US CA Sunnyvale
- 专利权人: OMNIVISION TECHNOLOGIES, INC.
- 当前专利权人: OMNIVISION TECHNOLOGIES, INC.
- 当前专利权人地址: US CA Sunnyvale
- 主分类号: G01J1/18
- IPC分类号: G01J1/18 ; H04N5/217
摘要:
An apparatus for measuring the power frequency of a light source includes a photo-sensitive transistor, a modulators and a logic unit. The photo-sensitive transistor generates an electrical signal that is responsive to light incident thereon from the light source. The modulator generates a modulated signal based on the electrical signal that toggles at a rate substantially proportional to the power frequency of the light source. The logic unit is coupled to receive the modulated signal and determine its toggling frequency.