Photometry device

Abstract

In a photometry device, photopic vision luminance Lp is measured by a first luminance measuring unit including a first light filter 4 and a first photoelectric converter 5, and scotopic vision luminance Ls is measured by a second luminance measuring unit including a second light filter 6 and a second photoelectric converter 7. A calculation part 8 calculates mesopic vision luminance Lmes based on a measurement value (photopic vision luminance Lp) of the first luminance measuring unit and a ratio of a measurement value (scotopic vision luminance Ls) of the second luminance measuring unit to the measurement value (photopic vision luminance Lp) of the first luminance measuring unit. Consequently, the photometry device can improve measurement accuracy of the brightness (mesopic vision luminance) in mesopic vision.

Dependencies are inferred from the claim text.