Optical recording medium, master disc for manufacturing optical recording medium, and device and method for manufacturing master disc for manufacturing optical recording medium

摘要

An optical recording medium allowing high-density recording, where a groove having a shallow U-shaped cross section wider than certain width, a master for manufacturing optical recording medium, a manufacturing apparatus thereof, and a manufacturing method thereof are provided. A exposure beam (61) and a exposure beam (62) are recombined together with a first exposure beam (60) in a second PBS (47) so that traveling directions thereof may be the same direction. At this time, the exposure beam (61) and the exposure beam (62) are arranged so that both optical axes may be aligned at certain distance. Thereby, a width of a spot formed by combining these beams can be extended, and light exposure of the spot can be proper to form a shallow groove, as typically showed in FIG. 3.