| 摘要 |
PURPOSE:To secure focusing by displaying a focus zone which varies according to the movement of a focusing member and a zooming adjusting member for a lens in an electronic viewfinder. CONSTITUTION:The output voltage of a detection resistance 6 for a focusing ring position is converted by a voltage follower 21 into a signal S21, and the output voltage of a detection resistance 7 for a zoom ring position is converted into a signal S20 by a voltage follower 22; and those signals S21 and S20 are used as correcting signals of monostable multivibrators 22, 23, 24, and 25. The monostable multivibrator 24 receives the correcting signal S20 as a pulse input and an output S22 is supplied to a clock input CL; and its output S24 is a pulse with pulse width t4. Then, outputs S24 and S25 are supplied to the video circuit (not shown in figure) of the electronic viewfinder through an NAND circuit 26. The display of focus zone is displayed brightly by mixing the output pulses s24 and S25 with the input signal of the electronic viewfinder. |
