EXPOSURE DEVICE OF MASTER DISK FOR OPTICAL RECORDING MEDIUM, EXPOSURE METHOD OF MASTER DISK FOR OPTICAL RECORDING MEDIUM, OPTICAL PICKUP AND OPTICAL RECORDING METHOD

摘要

PROBLEM TO BE SOLVED: To provide an exposure device and an exposure method of a master disk for optical recording medium which enables forming a rugged pattern such as a pit and a group with high accuracy and to provide an optical pickup and an optical recording method which enables performing the recording to an optical disk with high recording density. SOLUTION: This exposure device of a master disk 10 for optical recording medium is constituted so as to be provided with an objective part 7 having a semiconductor laser or gas laser which emits a laser beam and an optical fiber 8 and form an opening whose diameter is smaller than wavelength λ of the laser beam on the emitting end surface 7A of the optical fiber 8. Then, the laser beam is applied to photoresist via the optical fiber 8 and the exposure to the master disk 10 for optical recording medium is performed in such a state that the length WD between the photoresist on a substrate and the emitting end surface 7A is made shorter than the wavelength λ of the laser. Likewise, this optical pickup is constituted so as to be provided with an objective part having a semiconductor laser and an optical fiber and form an opening whose diameter is smaller than the wavelength λ of the laser beam on the emitting end surface of the optical fiber. Further, the laser beam is applied to a recording layer via the optical fiber and the recording of information is performed in such a state that the length between the recording layer of optical recording medium and the emitting end surface of the optical fiber is made shorter than the wavelength λ of the laser beam.