| 摘要 |
PURPOSE:To provide the optical head including a front automatic light quantity controller which reduces the quantity of return light and attains sufficiently stable laser oscillation. CONSTITUTION:A semiconductor laser which oscillates laser light, optical systems 12, 13, and 14 which lead this laser light to an optical disk 15, and a light quantity detector 18 which receives a part of laser light led to the optical disk 15 by optical systems 12, 13, and 14 and detects the quantity of light are provided. A condenser lens 19 provided on the laser light incidence side of the light quantity detector 18 and a light shielding body 20 which is provided between the condenser lens 19 and the light quantity detector 18 and has a transmission hole 20a, which permits the laser light condensed by the condenser lens 19 to pass through, and intercepts laser light reflected from the light quantity detector are provided besides to constitute the optical head. |
