Patent ID: 6088534
Filing Date: 2000-07-11
Classification: G03B

Abstract:
A camera provided with an aperture controllable shutter having a diaphragm, comprising:a photographing lens having a variable focal length to be set in a desirable focal length, the full open aperture diameter thereof being constant as the focal length varies so that the full open aperture value thereof is varied;a detector which detects the set focal length of the lens;a first decision means for determining the extent to which the aperture diameter is capable of being controlled toward an opening direction of the aperture controllable shutter in accordance with the focal length detected by said detector;a light metering device which measures the brightness of an object to be taken;a driving mechanism which actuates the diaphragm of the aperture controllable shutter for opening the aperture;a second decision means for determining the movement of the diaphragm of the aperture controllable shutter in accordance with the full-aperture diameter determined by the first decision means and the object brightness measured by said light metering device; anda controller which controls the driving mechanism corresponding to the movement of the diaphragm determined by said second decision means.