LEDs have been in use for some time in automotive applications, particularly in the center high mount stop lights (CHMSL). The LEDs are rugged and have extremely long life. The LEDs in use for CHMSLs have been hard-wired into position and generally, are not easily replaceable. Recently, the use of LEDs for stoplights and taillights has increased but, again, a simple, replaceable unit with adequate light output has not been forthcoming. U.S. Published Patent Application No. 2003/0063476 A1, assigned to the assignee of the present invention, discloses a replaceable LED lamp capsule having LED chips arranged about the periphery of a shaft; however, heat dissipation can be a problem with such a construction. Part of the latter problem arises because, at the power requirements necessary to supply the requisite light output for automotive use, a substantial amount of heat is generated which must be removed or the lifetime of the LEDs is severely limited.
USPTO Backgrounds
USPTO Backgrounds