understanding the invention and controller 300 and sensor 301 may be fabricated as a single integrated device the exterior surface 107 of elongate heat sink 101 has a plurality of light emitting diodes 109 disposed thereon each led 109 in the illustrative embodiment comprises a white light emitting led of a type that provides a high light output each led 109 also generates significant amount of heat that must be dissipated to avoid thermal destruction of the led as noted above cooling device 199 provides cooling to avoid thermal destruction by combining a plurality of leds 109 on elongate thermally conductive member or heat sink 101 a high light output light source that may be used for general lighting is provided conductive paths 129 are provided to connect leds 109 to an electrical connector 111 the conductive paths may be disposed on an electrically insulating layer 131 or layers disposed on exterior surface 107 in the illustrative embodiment shown in the drawing figures the conductive paths and insulating layer are provided by means of one or more flexible printed circuits 113 that are permanently disposed on surface 107 as more easily seen in fig6 printed circuit 113 includes an electrically insulating layer 131 that carries conductive.