| 摘要 |
PURPOSE:To attain accurate driving control over a focusing optical system by controlling the speed of a motor according to pulses from a 2nd pulse generating means. CONSTITUTION:Part of luminous flux passed through a main mirror 33 is reflected by a submirror 38 and guided to a photoelectric conversion part 39. The output signal of this photoelectric conversion part 39 is outputted to a 2nd control circuit 40, which calculates a defocusing quantity. This focusing quantity is transmitted to a 1st control circuit 31 in a lens barrel 41 and a 1st control circuit 31 calculates the lens driving quantity command value of the focusing optical system L2 according to the defocusing quantity and drives a motor 9 through a motor driving circuit 42. Consequently, the motor speed is stabilized and the position control accuracy of a lens is improved. |
