exemplary illustrations of different array patterns of leds are shown in fig1 a and 1 c and fig3 typical numbers of leds in an array can range from several dozen e g 80 leds in the exemplary 4 u00d7 20 array of fig3 to several hundreds as in the 437 leds in the exemplary 19 u00d7 23 array in fig1 a and 1 c more or fewer leds may be used and other patterns may be selected based on specific lighting requirements for the desired application and the light output of the individual leds selection of appropriate led numbers and arrangements is within the level of skill in the art a plurality of copper traces 4 printed on the upper surface of the pcb 12 serve as the electrical connection to each of the leds for delivering power for operation in the preferred embodiment pcb 12 is a metal core board mcpcb fig3 illustrates the structure of the mcpcb which is formed by laminating a thermally conductive dielectric layer 13 e g g10 epoxy or similar and a high thermal conduction metal base 14 in the preferred embodiment the metal base 14 is copper although aluminum or other metals may be used openings 11 formed through dielectric layer 13 allow direct contact between the led thermal pads and metal base 14 for optimal heat conduction as illustrated in fig3 the metal base has small pedestals formed on its upper surface to extend though the openings 11 in the dielectric layer 13 to contact the thermal pad of the leds an alternative approach would be to make the.