JPS57120805A - Inspecting method of surface defect - Google Patents

Inspecting method of surface defect

Info

Publication number
JPS57120805A
JPS57120805A JP594281A JP594281A JPS57120805A JP S57120805 A JPS57120805 A JP S57120805A JP 594281 A JP594281 A JP 594281A JP 594281 A JP594281 A JP 594281A JP S57120805 A JPS57120805 A JP S57120805A
Authority
JP
Japan
Prior art keywords
produced
space
contrast
interference
defects
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP594281A
Other languages
Japanese (ja)
Other versions
JPH0158442B2 (en
Inventor
Tomohiro Kuji
Kazuo Yamaguchi
Nobuyuki Akiyama
Shigeo Endo
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Proterial Ltd
Original Assignee
Hitachi Metals Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hitachi Metals Ltd filed Critical Hitachi Metals Ltd
Priority to JP594281A priority Critical patent/JPS57120805A/en
Publication of JPS57120805A publication Critical patent/JPS57120805A/en
Priority to US06/695,231 priority patent/US4647196A/en
Publication of JPH0158442B2 publication Critical patent/JPH0158442B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/84—Systems specially adapted for particular applications
    • G01N21/88—Investigating the presence of flaws or contamination
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
    • G01B9/00—Measuring instruments characterised by the use of optical techniques
    • G01B9/02—Interferometers
    • G01B9/0209—Low-coherence interferometers

Abstract

PURPOSE:To prevent overlooking owing to the insufficiency of contrast by generating always a pair or more of bright and dark interference fringes within a detection range. CONSTITUTION:A dark interference fringe 44 is produced in the position of a space 41 where the reflected light from surface 8 of an object to be inspected and the reflected light from a virtual image 9 on the surface of a reference mirror weaken to each other on account of interference. Further, a interference fringe 45 is produced in the position of space 42 differing from space 43 as extent of 1/2lambda from space 41. If the conditions of the interference are changed along the direction of the movement or the like of the object 8 under such conditions, contrast can be given to defects 25 depending upon locations. The determination of places where the good contrast is obtained depends upon the rate of ruggedness of the defects, and if arrangement is so made that at least a pair or more of bright and dark interference fringes are produced within the range that can be detected with a detector, 1-2 places where the contrast maximizes are produced and the detection of the defects is made possible.
JP594281A 1981-01-20 1981-01-20 Inspecting method of surface defect Granted JPS57120805A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP594281A JPS57120805A (en) 1981-01-20 1981-01-20 Inspecting method of surface defect
US06/695,231 US4647196A (en) 1981-01-20 1985-01-28 Surface flaw detection method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP594281A JPS57120805A (en) 1981-01-20 1981-01-20 Inspecting method of surface defect

Publications (2)

Publication Number Publication Date
JPS57120805A true JPS57120805A (en) 1982-07-28
JPH0158442B2 JPH0158442B2 (en) 1989-12-12

Family

ID=11624947

Family Applications (1)

Application Number Title Priority Date Filing Date
JP594281A Granted JPS57120805A (en) 1981-01-20 1981-01-20 Inspecting method of surface defect

Country Status (1)

Country Link
JP (1) JPS57120805A (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0356543U (en) * 1989-10-03 1991-05-30

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5417764A (en) * 1977-07-08 1979-02-09 Nippon Telegr & Teleph Corp <Ntt> Plane shape measuring system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5417764A (en) * 1977-07-08 1979-02-09 Nippon Telegr & Teleph Corp <Ntt> Plane shape measuring system

Also Published As

Publication number Publication date
JPH0158442B2 (en) 1989-12-12

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