WARP ANGLE MEASURING EQUIPMENT AND WARP ANGLE MEASURING METHOD OF OPTICAL RECORDING MEDIUM

摘要

Warp angle measuring equipment and a warp angle measuring method of an optical recording medium capable of measuring the warp angle of an optical disc or a cartridge for the optical disc incident to environmental variations, e.g. abrupt variation of humidity, temperature, or the like, in a short time. The warp angle measuring equipment (10) of an optical recording medium comprises a thermostat (22) containing an optical recording medium (20) where an article to be measure, i.e. an optical disc (16), is loaded to a cartridge (18) and conditioning the circumference of the optical recording medium (20) to specified environmental conditions, a laser oscillator (24) for oscillating a laser beam and irradiating the optical disc (16) with the laser beam, and a light receiver (26) for receiving the laser beam reflected off the optical disc (16) and detecting the relative angle of a reflection light path L2 to a laser beam irradiation light path L1.