LOW-PRESSURE ARC DISCHARGE LAMP HAVING INCREASED SURFACE BRIGHTNESS

摘要

An arc discharge lamp having a sealed envelope including a major body portion and at least one minor transverse end portion. A non-specular light diffusing surface is axially located between the minor transverse end portion and one of the lamp electrodes. A phosphor layer within the sealed envelope subtends the major body portion of the envelope. The surface brightness of the phosphor layer as viewed through the minor transverse end portion of the envelope is greater than the intensity of the external surface brightness of the phosphor layer on the major body portion of the envelope during operation of the lamp. A lamp array for use as an element in a picture display is also disclosed including a plurality of sealed envelopes. In the case of a color presentation of information, one picture element is composed of three sealed envelopes phosphor costed with the primary colors red, green and blue.