Abstract: A lapping medium comprising a supporting body and a lapping layer formed on the supporting body. The lapping layer includes an abrasive and a binder. The abrasive comprises silica grains, which are pretreated with at least one coupling agent selected from a group consisting of a silane coupling agent, a titanate coupling agent, and an aluminum-contained coupling agent, and a binder.

Abstract: A light beam recording device. A light beam irradiated from a light beam irradiating device is scanned onto an object to be illuminated, which is provided in a vicinity of a focal position, while being focussed by a scanning optical system. A converging member is disposed on an optical path between the light beam irradiating device and the scanning optical system, and converges a light beam which is incident on the converging member. An optical path changing device is disposed in a vicinity of a converging position of a light beam which is converged by the converging member, and changes an optical path of the light beam.

Abstract: A cartridge including a cartridge case having a disc-shaped recording medium received therein so as to allow predetermined information signals to be recorded and reproduced, and a shutter molded of a synthetic resin to slidably open and close an opening portion formed on the cartridge case so as to allow at least a part of the disc-shaped recording medium to be exposed to the outside. In accordance with the present invention, the shutter is composed of an upper main plate, a lower main plate and a coupling plate which connects the upper main plate to the lower main plate via the coupling plate in an integrally molded state while having an U-shaped cross-sectional contour to hold the cartridge case in a clamped state. A gate used for performing a molding operation is formed on the outer surface of the side plate, with the position of the gate being determined such that it always remains within an effective opening region corresponding to the opening portion.

Abstract: A camera shake correction system which corrects the shaking of a picture image caused by the shake of a camera. In the camera shake correction system, a mirror is supported in front of a taking lens in such a manner that the mirror is free to incline about an angle of 45.degree. with respect to the optical axis of the taking lens, and the mirror is inclined at a half of the angular speed of the camera in the opposite direction to the shaking direction of the camera in accordance with the detection output of a shake sensor for detecting the shake of the camera, thereby stabilizing an object light incident on the image pickup surface of the camera.