| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical head and an optical disk apparatus which are small and which can achieve a high recording density. SOLUTION: Laser beams 3a radiated from a semiconductor laser 2 are shaped to be parallel beams 3b by a collimating lens 4, and it is bent at right angles by a return mirror 5 so as to be incident on a condensing hologram 10A. A parallel beam 3c which is incident on the condensing hologram 10A is condensed by the face 6b of a transparent medium 6 to be condensed for condensing, and a light spot 9b is formed on the face 6b to be condensed. Light which is condensed in the light spot 9b is passed through a very small hole 7a from the face 6b to be condensed, so as to be leaked to the outside of the transparent medium 6 for condensing as near-field light 9b. When a recording layer 8a on an optical disk 8 is irradiated with the near-field light 9b, a recording operation and a reproducing operation are performed. |
