Patent ID: 6314063
Filing Date: 2001-11-06
Classification: G11B

Abstract:
An integrated light emitting and receiving device for emitting light to a recording medium on which a plurality of pits are formed, focusing the light on the recording medium, receiving the reflected light influenced by the pits, and detecting a focus condition and tracking condition of the light focused on the recording medium in accordance with the information of the reflected light, said integrated light emitting and receiving device comprising:first and second light receiving elements which are provided on a substrate and are divided into a plurality of light receiving regions;a light emitting element which is provided on said substrate and emits light in a predetermined direction;a light splitting means which is provided on said first and second light receiving elements, emits the light input from said light emitting element to said recording medium, focuses the reflected light from said recording medium onto said first light receiving element, and focuses the reflected light reflected from the first light receiving element onto said second light receiving element;a tracking condition detecting means for detecting said tracking condition only from information on the amounts of light received by the light receiving regions of said first light receiving element; anda focus condition detecting means for detecting said focus condition only from information on the amounts of light received by the light receiving regions of said second light receiving element,wherein the second light receiving element is divided into four light receiving regions along two mutually crossing directions not along the longitudinal direction and transversal direction of said substrate.