Heretofore, an eye cup is mounted on a window of the eye piece portion of a view finder optical system of a camera. This eye cup is used to cut light coming from around the window of the eye piece portion, thus a user can see an image at the screen clearly through the view finder optical system. And also, the light coming into the camera's main optical system is cut by the eye cup being in contact with the eye. Thus, the camera's main optical system is not disturbed by the light.
However, some of the users wear glasses when viewing an object. The eye cup has a contact surface with a shape that is only made in accordance with the eye.
That is, the shape of the contact surface is not made in accordance with the shape of the lens of the glasses. Thus, a clearance exists between the lens and the contact surface. When a man puts on the glasses to take a photograph, light coming through the clearance is reflected by the face of the lens, then the light enters the camera's main optical system through the window of the eye piece portion.