William Brown
Accountancy at Timberwood St, Littleton, CO

5033833, Jul 23, 1991

Feb 26, 1990

7/485276

William C. Brown - Littleton CO

Martin Marietta Corporation - Bethesda MD

G02B 1306, G02B 1700

350443

An omni-directional antenna for use with light or other electromagnetic radiation has a surface extending outward from a central axis. The surface can be either radially symmetrical or asymmetrical. A portion of the surface adjacent to the axis is substantially transmissive and the remainder of the surface is substantially reflective. The reflective portion of the surface curves radially outward from the transmissive portion. The shapes and sizes of the transmissive and reflective portions of the surface are fixed such that upwardly directed rays striking the surface of the device parallel to the axis will be refracted by the transmissive portion and/or reflected by the reflective portion of the surface into a substantially omni-directional output pattern, when the device is used as a transmitter. Conversely, when used as a receiving antenna, rays striking the transmissive portion of the surface will be refracted and rays striking the reflective portion will be reflected into a downwardly directed output pattern substantially parallel to the axis.