Patent ID: 6849842

Claim:
A pyranometer comprising: a reversible electric motor having an output shaft; a curved flat opaque band of selected width, said band having one end coupled to output shaft so that said band can rotate in time with said output shaft and so that the axis of rotation of said band is normal to said one end thereof; a mount adapted to for attachment to a supporting structure so as to provide adjustment of said mount in a first degree; motor-support means pivotally attached to said mount so as to provide adjustment in a second degree; a light sensor having a light-receiving surface; sensor support means for supporting said sensor so that the center of said light-receiving surface is substantially coaxial with the axis of rotation of said band, said sensor support means being adapted to permit adjustment of said light sensor in a third degree; and motor control means for controlling operation of said motor so that periodically said band rotates through a selected angle from one stowed position to a second stowed position, with said stowed positions being such that said band casts a shadow on said light-receiving surface only while it is rotating.