Apparatus body of image pickup apparatus and lens adapter for equipping interchangeable lens to apparatus body

An apparatus body of an image pickup apparatus comprising:

• a fixing unit to which a lens adapter, to which an interchangeable lens is detachably attachable, is detachably attachable;
• and
• an electrical connecting portion that is formed as a first comb-shaped terminal that is electrically connectable with a second comb-shaped terminal of an electrical communication unit provided in the lens adapter,
• wherein the first comb-shaped terminal includes a plurality of contact members,
• wherein a contact position of each of the plurality of contact members of the first comb-shaped terminal contacting with the second comb-shaped terminal of the electrical communication unit is slidable relatively in an optical axis direction with respect to the apparatus body,
• wherein, in a state where the lens adapter is connected with the apparatus body, the first comb-shaped terminal is arranged further away from the optical axis than a third terminal of the electrical communication unit, which is electrically connected with the interchangeable lens, in a radial direction which is orthogonal to the optical axis direction,
• wherein in the apparatus body, a spacer is able to be inserted into a space between the apparatus body and the lens adapter in order to finely adjust a flange back, and
• wherein a length of a predetermined area in which the contact position of each surface of the plurality of contact members of the first comb-shaped terminal contacting with the second comb-shaped terminal varies relatively in the optical axis direction is sufficiently longer than an adjustment amount of the flange back.