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Journal of the Optical Society of America A

Journal of the Optical Society of America A

| OPTICS, IMAGE SCIENCE, AND VISION

  • Editor: Stephen A. Burns
  • Vol. 24, Iss. 5 — May. 1, 2007
  • pp: 1250–1265

Maximum permissible exposures for ocular safety (ANSI 2000), with emphasis on ophthalmic devices

François C. Delori, Robert H. Webb, and David H. Sliney  »View Author Affiliations


JOSA A, Vol. 24, Issue 5, pp. 1250-1265 (2007)
http://dx.doi.org/10.1364/JOSAA.24.001250


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Abstract

After discussing the rationale and assumptions of the ANSI Z136.1-2000 Standard for protection of the human eye from laser exposure, we present the concise formulation of the exposure limits expressed as maximum permissible radiant exposure (in J cm 2 ) for light overfilling the pupil. We then translate the Standard to a form that is more practical for typical ophthalmic devices or in vision research situations, implementing the special qualifications of the Standard. The safety limits are then expressed as radiant power (watts) entering the pupil of the eye. Exposure by repetitive pulses is also addressed, as this is frequently employed in ophthalmic applications. Examples are given that will familiarize potential users with this format.

© 2007 Optical Society of America

OCIS Codes
(170.4460) Medical optics and biotechnology : Ophthalmic optics and devices
(330.3350) Vision, color, and visual optics : Vision - laser damage

History
Original Manuscript: August 10, 2006
Manuscript Accepted: September 26, 2006
Published: April 11, 2007

Virtual Issues
Vol. 2, Iss. 6 Virtual Journal for Biomedical Optics

Citation
François C. Delori, Robert H. Webb, and David H. Sliney, "Maximum permissible exposures for ocular safety (ANSI 2000), with emphasis on ophthalmic devices," J. Opt. Soc. Am. A 24, 1250-1265 (2007)
http://www.opticsinfobase.org/josaa/abstract.cfm?URI=josaa-24-5-1250


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References

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  40. The discrepancy comes from reducing the source radiance from 100CBJcm−2sr−1 (ANSI Table 5b) to 20CBJcm−2sr−1 [ANSI Section 8.3(1)], and thus a factor of 5, to account for change in the pupil diameter instead of a factor 5.44 [ANSI Section 8.3(2)].
  41. Extrapolation of the MPΦ from cell 7 (Table ) toward shorter exposure durations intersects the MPΦ from cell 4a at a duration tex=2.75×10−3(CBα)1.33. The shortest value for tex occurs for CB=1(400<λ<450nm) and α=1.5mrad and equals 4.7ms.
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