Light collector for photosensitive luminaire control

Claim 1

A LUMINAIRE HAVING AN OUTER HOUSING, AN APERTURE IN SAID HOUSING, A PHOTOSENSITIVE CELL DISPOSED WITHIN SAID HOUSING AND ADJACENT SAID APERTURE, A LIGHT COLLECTING MEMBER CONSISTING OF A SOLID BODY OF TRANSPARENT MATERIAL HAVING A SUBSTANTIALLY SYMMETRICAL CONICAL CONFIGURATION, SAID LIGHT COLLECTING MEMBER EXTENDING THROUGH SAID APERTURE AND HAVING ITS BASE DISPOSED WITHIN SAID HOUSING AND IN OPPOSED RELATION TO SAID PHOTOSENSITIVE CELL, ONE SIDE OF THE CONICAL PORTION OF SAID LIGHT COLLECTING MEMBER HAVING A REFLECTIVE SURFACE PROVIDED THEREON SO THAT LIGHT RAYS MAY ENTER SAID COLLECTOR ONLY THROUGH THE OPPOSITE SIDE THEREOF AND SO THAT SAID LIGHT RAYS WILL BE REFLECTED TOWARD SAID BASE PORTION BY SAID REFLECTIVE SURFACE, SAID BASE PORTION HAVING A PLURALITY OF ANNULAR V-INCROSS-SECTION CONCENTRIC GROOVES FORMED THEREIN, THE APEX ANGLE OF SAID CONICAL LIGHT COLLECTING MEMBER BEING APPROXIMATELY 40 DEGREES AND THE APEX ANGLE OF EACH OF THE GROOVES BEING APPROXIMATELY 60 DEGREES.