Measurement of laser energy and power

Measurements of laser energy and power are discussed with emphasis on those methods which attempt to establish the accuracy or standards for such measurements. Devices to attenuate laser radiation are summarized. The principles and limitations of the methods are stressed rather than design details of the apparatus. It is found that standards for the measurement of laser power and energy are yet to be definitely established. Thus caution should be exercised in accepting stated accuracies for laser output measurements.