OSA's Digital Library

Optics Express

Optics Express

  • Editor: Michael Duncan
  • Vol. 12, Iss. 12 — Jun. 14, 2004
  • pp: 2610–2615

Random target method for fast MTF inspection

Sampo M. Backman, Anssi J. Makynen, Timo T. Kolehmainen, and Kai M. Ojala  »View Author Affiliations

Optics Express, Vol. 12, Issue 12, pp. 2610-2615 (2004)

View Full Text Article

Enhanced HTML    Acrobat PDF (236 KB)

Browse Journals / Lookup Meetings

Browse by Journal and Year


Lookup Conference Papers

Close Browse Journals / Lookup Meetings

Article Tools



A random target method for fast MTF inspection is proposed. The setup includes a random target, lens under test and a CCD camera with focus adjustment. The target consists of a random black and white pattern of a flat spectrum. The MTF of the lens is acquired by imaging the random target on the CCD using the lens under test, and then analyzing the spatial frequency content of the image. Frequency range up to about 50 cycles/mm is possible using commonly available CCD imagers. Measurement speed and precision depend on the sample matrix size used in calculation. A matrix of 128*128 samples per measured field point provides better than 2% precision and a few second’s total execution time (ordinary PC-computer) per lens including best focus evaluation and the measurement of tangential and sagittal MTF curves of 5 field points. Thus fast MTF inspection of low to medium quality lenses seems possible.

© 2004 Optical Society of America

OCIS Codes
(110.4100) Imaging systems : Modulation transfer function
(120.4630) Instrumentation, measurement, and metrology : Optical inspection

ToC Category:
Research Papers

Original Manuscript: April 8, 2004
Revised Manuscript: May 25, 2004
Published: June 14, 2004

Sampo Backman, Anssi Makynen, Timo Kolehmainen, and Kai Ojala, "Random target method for fast MTF inspection," Opt. Express 12, 2610-2615 (2004)

Sort:  Journal  |  Reset  


  1. H. Kubota and H. Ohzu, �??Method of Response Function by Means of Random Chart,�?? 47, 666-667 (1957). [CrossRef]
  2. A. Daniels, G. Boreman, A. Ducharme and E. Sair, �??Random transparency targets for modulation transfer measurement in the visible and infrared regions,�?? Opt. Eng. 34, 860-868 (1995). [CrossRef]
  3. E. Levy, D. Peles, M. Opher-Lipson and S.G. Lipson, �??Modulation transfer function of a lens with a random target method,�?? Appl. Opt. 38, 679-683 (1999). [CrossRef]
  4. E.C. Ifeachor and B.W. Jervis, Digital signal processing (Prentice Hall, 2002), Ch. 3.
  5. Sine Patterns LLC, 3800 Monroe Avenue, Pittsford, NY 14534, USA.

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.

« Previous Article  |  Next Article »

OSA is a member of CrossRef.

CrossCheck Deposited