Learning Center
Light Measurement Basics
Radiometry, Spectroradiometry, & Photometry
Colorimetry Concepts
Radiometers & Photometers
Luminance Meters & Colorimeters
Summary & Reference

Summary and Reference

Summary
If precise measurement of light is required, the spectroradiometric method is the most ideal and comprehensive method as it records the spectral characteristics of light and further processes them mathematically to obtain radiometric, spectroradiometric, photometric, and colorimetric data.

When portability, speed of measurement, and cost of investment, is of priority, filter photometers are still preferred. However, one should have a good understanding of the f1’ value of the photometer and its calibration method. This information is important to ascertain whether the photometer is appropriate to measure the light source under test, considering its spectral energy distribution.

Finally, one should choose an instrument which make direct measurements of light characteristics, such as luminance, illuminance, luminous intensity, luminous flux and should not attempt any form of conversions across measurement geometries.

Reference
Billmeyer, Fred W (1981). Principles of color technology—2nd Edition. Wiley & Sons, New York.

Hutson, Geoffrey, H. (1990). Color Television — 2nd Edition. McGraw-Hill Book Company Europe, England.

The Photonics Dictionary — A Four-Book Set (1993). United States of America.

Joseph B. Murdoch. Illumination Engineering — From Edison’s lamp to the laser. Macmillian Publishing Company, England.

D. Allan Roberts. Radiometry/Photometry Terms. The Photonics Design and Applications Handbook 1993, United States of America.

Daniel C. McCarthy. Integrating Sphere Aids Absolute Calibration of Lamps. Photonics Spectra—December 1998, United States of America.

Richard Distl. Measure What You See. Photonics Spectra—May 2000, United States of America.

Ian K. Edwards. Counting Coup — Photometry: Origin of the science to applying handheld equipment. LD&A — December 1993.

Clarence E. Rash and Everette McGowin III. Measuring Light. Information Display 9/96. SID 1996.

Kenneth A. Miller. Colorimetry: Methods and Tools. The Photonics Design and Applications Handbook 1993, United States of America.