Development of a Photometer Having Variable Spectral Responsivity

抄録

A photometer having variable spectral responsivity has been developed. The equipment is composed of a linear variable interference filter (LVIF), a MOS linear image sensor (CCD), driver/amplifier circuits, a 12-bits A/D converter and a note-type personal computer. The intrinsic relative spectral responsivity has been calibrated throughout the wavelength range from 400 to 700 nm by using the distribution temperature standard lamps. Then, it is possible to change its effective spectral responsivity as desired by weighting the output of each CCD element. In this study, the performance of the equipment as an illuminance meter, a simple spectroradiometer and a colorimeter has been evaluated by setting the relative spectral responsivity of the equipment to the spectral luminous efficiency, to a constant and to the matching functions, respectively. As a result, it is shown that the equipment has similar performance to a precise class of illuminance meter on the market. It is confirmed that the performance of the equipment almost meets the requirement for its use as a simple spectroradiometer and a colorimeter. Consequently, it is expected that this equipment can function as a mesopic photometer whose spectral responsivity varies with brightness.