Abstract: An arc lamp assembly which includes in combination a reflector and a light source which is surrounded by said reflector. A dichroic coating on the reflector functions to reflect radiation in the range of about 300 to 600 nm. The light source is an arc lamp which contains a metal halide fill component which includes a mixture of scandium iodide, or other suitable lanthanide, indium iodide, sodium iodide and sodium iodide, whereby the lamp assembly emits effective amounts of WV radiation to cure selected chemical compositions.

Abstract: A high performance miniature projection lamp which includes a glass envelope having a pair of opposite neck portions each with a coaxial central opening having a reduced section and an hermetically sealed central chamber having a volume of about 130 mm.sup.3 which contains a fill. The fill includes an argon pressure at room temperature at a range of about 0.5 atmospheres to about 2.0 atmospheres and mercury in an amount in the range of about 5 mg to about 15 mg, and a mixture of metal halide material in an amount from about 50 up to 1000 micrograms. A pair of axially aligned electrodes are positioned at opposite neck portions and separated form each other by a predetermined distance. The electrodes each have a shank portion which each having a coil wrapped around its end.

Abstract: An improved compact, white color and pulse operated high pressure sodium vapor arc discharge lamp employing a radiation sensitive getter RF flashed onto the inner surface of the outer lamp envelope has a ceramic radiation shield interposed between the arc tube and getter.

Abstract: A reflector lamp assembly having an integral photo-sensor and sensing circuit arrangement associated therewith provides for sensing the ambient light conditions at a point adjacent the top surface of the lamp envelope. The photo-sensor element is disposed within a sensor housing member mounted along an edge portion of the top surface of the lamp. A channel pathway is integrally formed with the sensor housing member and extends along the side lamp envelope to protect the sensor lead wires extending from the photo-sensor device to the sensing circuitry contained in the threaded screw base. The sensing circuitry is disposed vertically within a cavity formed in the bottom of the screw base so as to achieve optimum thermal dissipation properties for the sensing circuit. A collimator tube can be inserted into an opening formed at the top of the sensor housing member so as to control the field of view for sensing the ambient light conditions occurring near the top surface of the lamp assembly.

Abstract: The present invention is directed to a control circuit for providing a substantially constant current to a high-pressure sodium lamp. The control circuit preferably comprises a circuit for providing a rectified voltage signal, and a ballast having first and second contacts to operatively connect the lamp therebetween. The ballast generates and controls a peak current through the lamp based on the value of a controlled voltage. The control circuit further comprises a current sensor to sense the amount of current through the lamp, and a buck-boost voltage control circuit to control the value of the controlled voltage in order to provide a substantially constant peak current through the lamp based on the amount of current sensed by the current sensor. By controlling the amount of voltage seen by the lamp, the buck-boost voltage control circuit controls the amount of current through the lamp, thereby providing constant color temperature regardless of the fluctuations in lamp impedance.