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EP 0136726 A3 19860122 - EMISSIVE MATERIAL FOR HIGH INTENSITY SODIUM VAPOR DISCHARGE DEVICE

Title (en)

EMISSIVE MATERIAL FOR HIGH INTENSITY SODIUM VAPOR DISCHARGE DEVICE

Publication

EP 0136726 A3 19860122 (EN)

Application

EP 84111973 A 19841005

Priority

US 53960583 A 19831006

Abstract (en)

[origin: EP0136726A2] A high intensity sodium vapor discharge device includes an elongated envelope containing an elongated arc tube having a fill of noble gases and an electrode with emissive material thereon or therein with a free energy of formation per mole of oxygen more negative than the free energy of formation of barium oxide.

IPC 1-7

H01J 61/073

IPC 8 full level

H01J 61/073 (2006.01)

CPC (source: EP)

H01J 61/0737 (2013.01)

Citation (search report)

[X] US 4052634 A 19771004 - DE KOK JOHANNIS
[X] IEE PROCEEDINGS, vol. 128, no. 6, part A, September 1981, pages 415-441, Old Woking, Surrey, GB; J.A.J.M. VAN VLIET et al.: "High-pressure sodium discharge lamps"

Designated contracting state (EPC)

BE DE FR GB NL

DOCDB simple family (publication)

EP 0136726 A2 19850410; EP 0136726 A3 19860122; CA 1227521 A 19870929

DOCDB simple family (application)

EP 84111973 A 19841005; CA 464359 A 19840928