Abstract

Photometric standards can be attained using silicon photodiodes whose absolute spectral responsivity is self-calibrated. However, this method requires laborious measurements at many wavelengths over the visible region. In this paper a new method is proposed in which the responsivity [A / m] for the photometric quantity of a silicon photodiode, which is combined with a Vλ-correction filter of known spectral transmittance, can be self-calibrated by measuring the surface reflectance and the recombination loss of the silicon photodiode for white light. The derived equation for this method requires that the spectral responsivity of the monitor detector for the surface reflectance measurement be proportional to wavelength. This requirement is approximately fulfilled by high quality silicon photodiodes, but this approximation causes a systematic error. To clarify this error, computer simulation has been applied using the measured spectral data of commercially available silicon photodiodes both for the self-calibration sample and for the monitor detector, and of Vλ-correction filters, with data of CIE Standard Source A as white light. The simulation revealed that the systematic error was <0.2%.

© 1989 Optical Society of America