Being the luminous intensity sensor which detects the luminous intensity of the luminous intensity control unit null interior which

摘要

PROBLEM TO BE SOLVED: To accurately correctly detect an illuminance distribution in a room in a simple structure of good construction convenience by setting a plurality of photodetecting elements in a sensor main body, and separating a light from a photodetecting window by a shielding plate set between the photodetecting elements. ;SOLUTION: Photodetecting elements (photodiodes) 15a, 15b for detecting an external illuminance (luminous flux) entering through a photodetecting window 14 are securely set to a printed board 16 at a ceiling part inside a sensor main body 1c. The photodetecting window 14 for detecting the external luminous flux is formed at a design face 13 at a lower part of the sensor main body 1c. A shielding plate 17a controlling an angle (a direction) of incidence of light detected at each photodetecting element 15a, 15b, that is, controlling a condensation area is provided at the photodetecting window 14. The shielding plate 17a completely separates a luminous flux α from a direction of the window and a luminous flux β from a direction opposite to the window, and therefore the photodetecting elements 15a, 15b set via the shielding plate 17a detect the luminous fluxes α, β, separately. Accordingly, an illuminance of a plurality of detection areas can be detected correctly.;COPYRIGHT: (C)1998,JPO