Illuminating device

Claim 1

AN ILLUMINATING DEVICE COMPRISING A. A CIRCULAR PLATE OF TRANSLUCENT, LIGHT DISPERSING MATERIAL, B. A CIRCULAR LIGHT TUBE LYING IN A PLANE PARALLEL TO, AND SPACED FROM SAID PLATE AND BEING CONCENTRIC WITH THE LATTER, AND C. MEANS DEFINING A REFLECTING SURFACE OF REVOLUTION EXTENDING FROM THE PERIPHERY OF SAID CIRCULAR PLATE AND ENVELOPING SAID LIGHT TUBE, SAID REFLECTING SURFACE OF REVOLUTION BEING DEFINED BY A GENERATRIX REVOLVED ABOUT AN AXIS PERPENDICULAR TO SAID PLATE AT THE CENTER OF THE LATTER, SAID GENERATRIX INCLUDING (1) AN OUTER PART FORMED SUBSTANTIALLY AS AN ARC OF AN ELLIPSE HAVING ITS MAJOR AXIS EXTENDING RADIALLY WITH RESPECT TO SAID AXIS WITH THE RADIALLY OUTER FOCUS OF THE ELLIPSE LOCATED AT SAID LIGHT TUBE, AND (2) AN INNER PART EXTENDING FROM SAID ARC OF AN ELLIPSE TO SAID AXIS OF REVOLUTION AND FORMED SUBSTANTIALLY AS A REVERSED CURVE, SAID INNER PART OF THE GENERATRIX DEFINING A MOUND-LIKE CENTRAL PORTION ON SAID REFLECTING SURFACE OF REVOLUTION WHICH IS DIRECTED TOWARD SAID PLATE. SO THAT LIGHT RAYS EMITTED FROM SAID LIGHT TUBE IN DIRECTIONS AWAY FROM SAID PLATE ARE REFLECTED BY SAID SURFACE SO AS TO IMPINGE ON THE PLATE AND THEREBY EFECT HOMOGENEOUS ILLUMINATION OF THE PLATE WITH A HIGH LEVEL OF INTENSITY.