| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical head device which is suitable for a high-density disk which is made multi-valued in the height direction of pits of the optical information recording medium by improving the resolution in a focus vibrating direction without decreasing the light convergence diameter of a beam spot. SOLUTION: This device is provided with a light source 1 which emits a light beam, an objective 4 which converges the light beam on the optical information recording medium D, a condenser lens 4 which converges the reflected light of the light beam from the optical information recording medium D, and an optical detecting means 6 which detects the converged reflected light and outputs a detection signal. Then the optical detecting means 6 detects the light through a pinhole member 5 which is arranged at the focus position of the condenser lens 4 closely to the detection surface side of the optical detecting means 6. |
