Detectors for wavelength independent radiometry

The development of spectrally flat detectors is discussed. Calibration of optical detectors and instruments is facilitated by the use of a convenient tunable source referred to a detector whose spectral response is well characterized or, preferably, is flat, which would obviate the need to perform detailed spectral measurements on each reference detector. Pyroelectric detectors have several advantages - ease of fabrication, excellent stability, and, as thermal detectors, a spectral response which can be enhanced by appropriate choice of absorbing coating and detector structure. The properties of black coatings and the design of light-trapping detector structures are considered, and various designs and responses of pyroelectric detectors are examined.