发明授权
- 专利标题: Flash unit
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申请号: US09486338申请日: 2000-02-25
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公开(公告)号: US06345156B1公开(公告)日: 2002-02-05
- 发明人: Makoto Isozaki , Junichi Takagi , Kazumi Koike , Mitsuhiro Moriya , Keiji Uchiyama , Yukitsugu Hata
- 申请人: Makoto Isozaki , Junichi Takagi , Kazumi Koike , Mitsuhiro Moriya , Keiji Uchiyama , Yukitsugu Hata
- 优先权: JP9-228524 19970825; JP9-243869 19970909
- 主分类号: G03B1505
- IPC分类号: G03B1505
摘要:
In a flash circuit of a flash device, a Zener diode (37) is connected to a tap point (23f) located at an intermediate position of a secondary coil of an oscillation transformer (23). The oscillation transformer (23) and an oscillation transistor (22) constitutes an oscillation circuit. A potential at the tap point (23f) changes proportionally to a voltage charged in a main capacitor (41). When the main capacitor (41) is charged up to a set voltage, the Zener diode (37) conducts a Zener current, which activates a stopping transistor (38) and thus deactivates the oscillation circuit. When a flash charge switch (51) is turned on, an end of a light guide portion of a charge condition indicator (60) protrudes out of a lens-fitted film unit. When the main capacitor (41) is charged up to the set voltage, a light emission element starts lighting, and the light from the light emission element is projected from the end of the light guide portion.
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