| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical pickup device in which miniaturization is attained and the number of parts is reduced and which copes with two wavelengths without using a composite prism. SOLUTION: The device is provided with a light emitting part 60 which emits first and second laser beams different in wavelength, a grating which generates a pair of sub beams, and a hologram which generates positive and negative high order light from the laser beam reflected by a recording medium and guides it to a light receiving part. The light receiving part is composed of a pair of tripartite light receiving elements 72, 76 which generate a reading signal and a focus error signal by a beam size method and a pair of two-set sub beam receiving elements 73, 77 one set each of which is provided in each of a pair of tripartite light receiving elements and which generate the tracking error signal by a three-beam method. The tripartite light receiving element is divided into three light receiving areas by two parallel parting lines, and the light emitting part is set up so that a straight line which connects respective light emitting points of the first and second light emitting sources is to be parallel with the parting line of the tripartite light receiving element. |
