Sulfur/selenium lamp with improved characteristics
Patent 5866980 Issued on February 2, 1999. Estimated Expiration Date: February 2, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
313/570, Greater than 760 torr313/571, Includes mercury in gas or vapor fill315/39, Discharge device load with distributed parameter-type transmission line (e.g., wave-guide, coaxial cable)315/245Resistance in the condenser circuit
The spectral energy characteristic of a discharge lamp is controlled by changing the density of the fill substance. The spectral characteristic can be shifted while substantially maintaining its shape by changing the density of the fill. A sulfur or selenium containing discharge lamp which is operated at a pressure of at least about 1 atmosphere contains a low ionization potential substance in the fill. Characteristics which are improved are one or more of spatial color uniformity, extinguishing characteristics, and bulb starting reliability. Particular substances which are added to the fill are alkali metal containing substances, III B metal containing substances, and alkaline earth metal containing substances. When light is reflected back into the bulb, the light which is re-emitted is stronger in the higher wavelengths.
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February 2, 2016. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
