Method and apparatus for measuring internal defects for position and depth
AssigneeMitsui Mining & Smelting Co., Ltd.
InventorsKazuo Moriya, Hideo Wada, Katsuyuki Hirai
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Abstract
A method for measuring internal defects of a specimen, comprising the steps of allowing a finely focused laser beam to be incident into a specimen from its surface and observing the scattered light of the said laser beam from inside the said specimen from the surface of the specimen and in a different direction to the optical axis of incidence of the laser beam.
Claims16
A methd of measuring internal defects of a specimen having a flat surface through which the defects are to be measured and which is sufficiently smooth for a laser beam to be incident into the specimen, comprising the steps of:
- allowing a laser beam to be incident into the specimen through said flat surface;
- and
- observing the scattered light of the incident laser beam from the defects through said flat surface and in a direction different from the optical axis of the incident laser beam,
- wherein the laser beam is finely contracted whereby the observed position of each defect corresponds to the depth of the defect.
An apparatus for measuring internal defects of a specimen having a flat surface through which the defects are to be measured and which is smooth enough for a laser beam to be incident into the specimen, comprising:
- means for allowing a laser beam to be incident into the specimen through said flat surface;
- and
- means for observing the scattered light of the incident laser beam from the defects through said flat surface and in a different direction from the optical axis of the incident laser beam,
- wherein the laser beam is finely contracted and the observed position of each defect corresponds to the depth of the defect.
Dependencies are inferred from the claim text.