| 摘要 |
PURPOSE:To obtain the moving body following zooming device which can be set optionally to subject image magnification by controlling a zoom drive until distance information obtained by distance measuring operation reaches a specific value and placing a zooming mechanism in follow-up operation so that a set field angle is obtained. CONSTITUTION:When a check switch 6 is turned on in moving body follow-up mode, a control arithmetic part 1 performs distance measuring operation and calculates the intersection of the image magnification of the number of AF pulses and image magnification at a zoom lens position to calculate and hold a code. When the switch 6 is pressed next, AF distance measuring operation is performed, a code for arithmetic is found from the obtained number of AF pulses and the held code, and a zoom driving mechanism 10 is driven by controlling a zoom driving circuit 9 so that a gray code (code for arithmetic) outputted by a zoom position sensor 8 reaches a specific value D. Consequently, the position of a lens is so adjusted that the field angle which is set initially is obtained even if a subject distance varies after the field angle is set. This operation is performed continuously for the ON period of the switch 6 to hold constant image magnification at all times. Then a shutter is put in operation with a release switch 7 ON. |
