发明名称 Exposure control device of a video camera and method therefor
摘要 An automatic exposure control device of a video camera for recording and tie-recording with proper exposure level including an iris mechanism having a two-fin type iris rotated by a ring portion of which the rotational speed is in proportion to an iris control value while an electric battery is switched on and a photograph button is pushed. Recording is actually started after a predetermined period is passed following the pushing of the photograph button. A photometric integrating circuit outputs an iris integrating value from a brightness element of a photograph signal. A microcomputer determines the iris control value from the iris integrating value. During the predetermined period after the pushing of the photograph button, the iris control value is increased and output for every field in order to control the iris with high speed. After this predetermined period following the pushing of the photograph button, recording is actually operated while the iris control value is decreased and output for every field in order to control the iris with low speed.
申请公布号 US5825417(A) 申请公布日期 1998.10.20
申请号 US19970825183 申请日期 1997.03.27
申请人 FUJI PHOTO FILM CO., LTD. 发明人 YOSHIDA, MASANORI
分类号 H04N5/235;G03B7/095;H04N5/238;(IPC1-7):H04N5/238 主分类号 H04N5/235
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