公开(公告)号：JP2001056300A

公开(公告)日：2001-02-27

申请号：JP23102399

申请日：1999-08-18

Applicant: SONY CORP

Inventor： TAKEDA MINORU ,  IMANISHI SHINGO ,  RODERIC KEERE

IPC: G11B7/004 ,  G01N21/95 ,  G11B7/09 ,  G11B7/125 ,  G11B7/26

Abstract: PROBLEM TO BE SOLVED: To detect defects of specific size without omission in an area used for exposure by irradiating an evaluation object disc master with evaluation laser beams of specific wavelength through an objective lens with specific numerical aperture, receiving the return light by a specified light receiving element, and processing the detected result. SOLUTION: In this disc master evaluating device 50, an air spindle 51 is moved in the radial direction of a disc master 2 or a glass master by a radially moving mechanism 52 in the state of the disc master 2 or glass master being rotatory-driven at the high speed rotating peed of 450 rpm for instance by the air spindle 51. Further in this state, evaluation laser beams L2 of 480-680 nm in wavelength are applied to irradiate the disc master 2 or glass master through an objective lens 53 of 0.8 or more in numerical aperture, and the return light is received by a light receiving element 71. The disc master evaluating device 50 processes the light receiving result S1 of the light receiving element 71 to detect a defect of about 100 nm of the disc master 2 or glass master.