A lens device is used with an imaging device having a imaging-lens and an aperture stop device. The sleep protector is cooperable with conventional cribs or beds, and is made up of a series of interconnected pipe members forming a support structure. An conductive body is provided at a lower end part of a body of the click rubber, and the base plate is provided with an upper contact and a lower contact which are vertically apart from each other and opposed to the conductive body.