| 摘要 |
PROBLEM TO BE SOLVED: To realize the reduction of the number of parts, miniaturization, cost reduction and high access, in an optical head in which recording is performed one side or both sides of a land and a groove, a light emitting/ receiving element, an optical medium recording/reproducing device and a method for detecting a track discriminating signal. SOLUTION: A spot forming means is provided among the optical head, the light emitting/receiving element, a light source and a light separating means of the optical recording medium recording/reproducing device, a main luminous flux which forms a main spot for recording and/or reproducing on the information recording surface of the optical recording medium is separated from a sub-luminous flux which forms a sub-spot in a position apart from the main spot on the information recording surface of the optical recording medium by diffracting light beams emitted from the light source, and moreover a focal position of the sub-spot which is formed on the information recording surface of the optical recording medium is shifted in the radial direction orthogonal to the track of the optical recording medium. |
