High pressure sodium lamp having reduced internal diameter

Abstract

A high pressure sodium lamp (100) having an evacuated glass envelope (6) with a plurality of electrically conductive support members therein and extending therethrough. An elongated arc tube (14) having a pair of electrodes (26) extending therethrough is affixed to the electrically conductive support members within the glass envelope. A gas fill includes a quantity of mercury and sodium within the elongated tube. The arc tube is selected from a translucent material that, when the lamp is operating, will have a wall temperature of about 1250 degrees Celsius, a wall loading of from about 18.9 to about 22.2 w/cm sqr., and a power consumption of from 150 to 400 watts. Further, the amount of mercury is reduced from 14.4 mgs/arc tube to 10.8 mgs/arc tube, allowing lamps having power consumption from 150 to 400 watts to pass the Toxicity Characteristics Leaching Procedure (TCLP).

Dependencies are inferred from the claim text.