Patent ID: 8824883

Claim:
A lens device for an image capturing apparatus incorporating a photographing lens and a diaphragm device configured to narrow an aperture area, the lens device comprising: a cylindrical housing that incorporates the photographing lens and the diaphragm device; a first operation ring that is mounted on an outer peripheral portion of the housing to be rotatable in a circumferential direction of the outer peripheral portion so as to adjust the aperture area of the diaphragm device; and a second operation ring that is mounted on the outer peripheral portion of the housing in parallel to the first operation ring to be rotatable coaxially with the first operation ring so as to adjust a transmittance of a light transmittance variable filter, wherein a correspondence relationship between an operation amount of the first operation ring and a change rate of an amount of transmitted light of the diaphragm device, and a correspondence relationship between an operation amount of the second operation ring and a change rate of an amount of transmitted light of the light transmittance variable filter are set to be the same.