Photometry

In this white paper, Pro-Lite’s Robert Yeo explains how the integrating sphere came into existence, what it does, how it works, and how it is used to simplify what would otherwise be complex measurements in fields such as radiometry & photometry, in measuring the optical properties of materials and in the calibration and distortion correction of cameras and image sensors.

The science of measuring the amount, spectral and spatial distribution of light emitted by a source is generally poorly understood. Few university-level physics or engineering syllabuses review the principles of optical radiation measurement, let alone the practicalities. This is despite our interacting with light almost constantly, both in nature and in our work and leisure activities. This white paper reviews the fundamental principles of light metrology.