Uniform frontal illumination of planar surfaces: where to place the lamps

Michael A. Gennert; Norman Wittels; Gary L. Leatherman

doi:10.1117/12.135853

1 June 1993 Uniform frontal illumination of planar surfaces: where to place the lamps

Michael A. Gennert, Norman Wittels, Gary L. Leatherman

Author Affiliations +

Optical Engineering, Vol. 32, Issue 6, (June 1993). https://doi.org/10.1117/12.135853

Abstract

A method is presented for placing line, point, and ring light sources to produce uniform illumination of planar surfaces. Optimization consists in setting to zero as many terms as possible in a two-dimensional Taylor series expansion of the surface illumination. We analyze several practical lighting arrangements and discuss the significance of symmetry in lighting design. Four conditions are sufficient to produce optimal illumination: (1) place all lamps in a single plane parallel to the illuminated surface; (2) arrange linear sources in parallel pairs; (3) arrange point-source lamps to achieve fourfold symmetry with respect to any two orthogonal axes lying in the surface, this requires a minimum of four lamps; and (4) select lamp heights so that a line connecting each lamp to the center of the illuminated surface forms specific angles with the surface normal: 30 deg for line sources and approximately 39 deg for point and ring sources. Any lamp arrangement meeting these conditions produces an illumination function in which at least three orders of terms of the Taylor series expansion are zero. We also discuss circumstances under which some of these conditions can be relaxed.

Citation Download Citation

Michael A. Gennert, Norman Wittels, and Gary L. Leatherman "Uniform frontal illumination of planar surfaces: where to place the lamps," Optical Engineering 32(6), (1 June 1993). https://doi.org/10.1117/12.135853

Published: 1 June 1993

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available