Invention Grant
- Patent Title: Strobe light-emission control apparatus
- Patent Title (中): 频闪发光控制装置
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Application No.: US10452204Application Date: 2003-06-03
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Publication No.: US06788892B2Publication Date: 2004-09-07
- Inventor: Takashi Yano
- Applicant: Takashi Yano
- Priority: JP2002-165251 20020606; JP2002-195402 20020704
- Main IPC: G03B1505
- IPC: G03B1505

Abstract:
When a strobe flash is not emitting light, a photoreception current that is output from a phototransistor is detected and correction current corresponding to amount of extraneous light is produced by a voltage-controlled current source. Further, a light-emission control apparatus, receives emitted light reflected from the subject and halts the light emission when a value obtained by integrating a photoreception signal exceeds a first predetermined threshold value. If a period of time from start of light emission by the discharge tube to that at which the integrated value exceeds the threshold value falls within a predetermined period of time, the integrated value is reset and integration is performed again. Further, the aperture of a diaphragm is reduced and the threshold value is raised from the first threshold value to a second threshold value.
Public/Granted literature
- US20030228143A1 Strobe light-emission control apparatus Public/Granted day:2003-12-11
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