Patent ID: 6931651
Filing Date: 2005-08-16
Classification: G11B

Abstract:
1. An optical pickup comprising: a synthetic resin-made base in which a collimator lens and an objective lens are disposed at one end opening of a light passage hole with a half mirror, the base having a mounting surface formed on another end opening of the light passage hole that is penetrating the base; a laser diode disposed in a laser hole communicating with the light passage hole; a resilient plate made of a leaf spring having a central through hole, a first end portion secured to the mounting surface in such a manner as to be heightwise adjustable by an adjusting screw, a pair of left and right hinge portions formed by cutting out a slit in the vicinity of a second end portion that is opposite to the first end portion, and a pair of left and right leg portions formed integrally at both side edge portions of the second end portion, the leg portions extending toward the first end portion along a horizontal longitudinal direction; and a printed circuit board with a photodiode, the printed circuit board secured to the resilient plate in face-to-face relation to the central through hole while being positioned in the horizontal longitudinal direction and a horizontal transverse direction; wherein laser light is projected from the laser diode onto a disk through the half mirror, the collimator lens, and the objective lens, and reflected light thereof is received by the photodiode through the half mirror and the central through hole in the resilient plate, so as to read information recorded on the disk; a pair of fixing holes are respectively formed in the leg portions in such a manner as to be provided on a transverse phantom line passing through a central portion of the resilient plate and at positions spaced apart an equal interval from a longitudinal phantom line passing through the central portion of the resilient plate and extending in the horizontal longitudinal direction; a pair of threaded holes are formed in the mounting surface in such a manner as to be provided on a transverse phantom line passing through a central portion of the base and extending in the horizontal transverse direction and at positions spaced apart an equal interval from a longitudinal phantom line passing through the central portion of the base and extending in the horizontal longitudinal direction; an elongated engaging hole is penetratingly provided in one of the leg portions along the horizontal longitudinal direction; an elliptical positioning projection is projectingly provided on the mounting surface in face-to-face relation to the engaging hole; a support pedestal which is one step higher is integrally formed at an end portion of the mounting surface; the resilient plate and the leg portions are positioned on the mounting surface by engaging the positioning projection with the engaging hole; and fixing screws are respectively screwed into the threaded holes through the fixing holes in the leg portions, so as to fix the leg portions to the mounting surface and press the second end portion of the resilient plate against the support pedestal.