OSA's Digital Library

Applied Optics

Applied Optics


  • Vol. 27, Iss. 22 — Nov. 15, 1988
  • pp: 4620–4625

Inspection of surface flaws by comparator microscopy

L. R. Baker  »View Author Affiliations

Applied Optics, Vol. 27, Issue 22, pp. 4620-4625 (1988)

View Full Text Article

Enhanced HTML    Acrobat PDF (1197 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



The increasing attention paid in recent years to control of surface quality has exposed the lack of objectivity of existing standards relating to flaws such as digs and scratches. The present requirements of the customer and supplier of optical components for improved standards are discussed, and recent attempts to satisfy these requirements are reviewed. It is concluded that a technique, described as comparator microscopy, in which a width of line or slit is identified which removes from a transmitted or reflected beam the same amount of light as the flaw under examination, has much in its favor in terms of user needs. The method, which is under consideration as the basis of an ISO standard, is described, and results are presented indicating how this concept of line-equivalent width can be used to compare different national standard flaws. Extending this technique to measure flaws and polish on-machine is suggested as a future possibility.

© 1988 Optical Society of America

Original Manuscript: March 21, 1988
Published: November 15, 1988

L. R. Baker, "Inspection of surface flaws by comparator microscopy," Appl. Opt. 27, 4620-4625 (1988)

Sort:  Author  |  Year  |  Journal  |  Reset  


  1. S. Martin, “Influence of Surface Defects on the Glare Characteristics of a Night Vision System with Refractive Optics,” Opt. Acta 25, 1113 (1978). [CrossRef]
  2. K. H. Guenther, P. G. Wiener, J. M. Bennett, “Surface Roughness Measurements of Low Scatter Mirrors and Roughness Standards,” Appl. Opt 23, 3820 (1984). [CrossRef] [PubMed]
  3. D. Nyyssonen, “Theory of Optical Edge Detection and Imaging of Thick Layers,” J. Opt. Soc. Am. 72, 1425 (1982). [CrossRef]
  4. M. Young, “Objective Measurement and Characterisation of Scratch Standards,” Proc. Soc. Photo-Opt. Instrum. Eng. 362, 86 (1982).
  5. E. G. Johnson, “Simulating the Scratch Standards for Optical Surfaces: Theory,” Appl. Opt. 22, 4056 (1983). [CrossRef] [PubMed]
  6. J. M. Bennett, D. K. Burge, J. P. Rahn, H. E. Bennett, “Standards for Optical Surface Quality Using Total Integrated Scattering,” Proc. Soc. Photo-Opt. Instrum. Eng. 181, 124 (1979).
  7. MIL-O-13830A (1975). Optical components for fire control instruments: general specifications covering their manufacture, assembly, and inspection.
  8. BS 4301 (1982). Recommendations for the preparation of drawings for optical elements and systems.
  9. DIN 3140/7. Surface defects.
  10. M. Young, E. G. Johnson, “Tunable Scratch Standards,” Proc. Soc. Photo-Opt. Instrum. Eng. 525, 70 (1985).
  11. M. Young, “Scratch-and-Dig Standard Revisited,” Appl. Opt. 25, 1922 (1986). [CrossRef] [PubMed]
  12. J. A. Slater, D. A. Cox, “Scratches: at What Price Quality?,” Proc. Soc. Photo-Opt. Instrum. Eng. 654, 68 (1986).
  13. A. J. Cormier, “Assessment of Current Scratch Standards,” Proc. Soc. Photo-Opt. Instrum. Eng. 805, 152 (1987).
  14. R. E. Parks, “Progress on International Optics Standards,” Opt. News 13(9), 31 (1987). [CrossRef]
  15. A. Huard, “Visibility Method to Classify Macroscopic Surface Defects for Both Reflection and Transmission Systems,” Proc. Soc. Photo-Opt. Instrum. Eng. 525, 36 (1985).
  16. L. R. Baker, “Microscope Image Comparator,” Opt. Acta 31, 611 (1984). [CrossRef]
  17. L. R. Baker, “Surface Texture and Imaging Quality of Mirrors,” Proc. Soc. Photo-Opt. Instrum. Eng. 830, 23 (1987).
  18. L. R. Baker, J. Singh, “Comparison of Visibility of Standard Scratches,” Proc. Soc. Photo-Opt. Instrum. Eng. 525, 64 (1985).

Cited By

Alert me when this paper is cited

OSA is able to provide readers links to articles that cite this paper by participating in CrossRef's Cited-By Linking service. CrossRef includes content from more than 3000 publishers and societies. In addition to listing OSA journal articles that cite this paper, citing articles from other participating publishers will also be listed.


Fig. 1 Fig. 2 Fig. 3
Fig. 4

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited