Abstract: There has been provided a drop-in cutting board assembly for an apertured countertop, wherein a vitreous cutting surface is located over a backing or strengthening member. A T-band holds the cutting surface and backing member together by means of a pair of opposed flanges joined together by an annular band located about the periphery thereof. An outwardly facing proportion of one of the flanges engages a peripheral margin of the countertop aperture to support the assembly in place and a channel formed integrally of the annular band extends below the countertop. A latch engages the channel and has free ends for engaging both the rearward portion of the backing member and the countertop for securing the assembly firmly within the aperture countertop.

Abstract: A reflector useful in dental surgical lighting systems has been developed, which reflector is derived from at least one base ellipsoid surface which has been divided into sections, each section being rotated outward so as to provide the cumulative effect of several ellipsoidal segments to produce a beam pattern of desired width.

Abstract: A reflector useful in dental surgical lighting systems has been developed, which reflector is derived from at least one base elipsoid surface which has been divided into sections, each section being rotated outward so as to provide the cumulative effect of several elipsoidal segments to produce a beam pattern of desired width.

Abstract: A luminaire for providing at least a shallow uniform equatorial zone of illumination above the pavement of airport taxiways and parking areas comprising a housing provided with an upper section having a vertical opening therethrough, a lens within the opening having a shallow frustoconical light exit face extending only slightly above the opening and a steeper generally conical light entrance face coaxial with and disposed below the light-entrance face, a lamp recessed substantially below the entrance face and proximate the axis of the light exit and entrance faces, and a reflector symmetrical about the axis of the exit and entrance faces for reflecting light rays from the lamp into the light entrance face at a predetermined range of angles of incidence therewith.