Low thermal-mass LEDs: size effect and limits

Finite Size Scaling and Low Mass Glueballs

We propose finite lattice effects as a probe of the glueball mass spectrum, and give an analysis of the recent SU(2) Monte Carlo data of Brower, Nauenberg and Schalk in terms of a gas of free glueballs. For Z 4 lattices with L = 4, 5, 6 fits are made to ~(m = 1/a~) which indicate a rather large effective number of degrees of freedom (i.e. statistical degeneracy where a spin J counts as 2J+ 1) f...

Thermal Management of LEDs: Package to System

Light emitting diodes, LEDs, historically have been used for indicators and produced low amounts of heat. The introduction of high brightness LEDs with white light and monochromatic colors have led to a movement towards general illumination. The increased electrical currents used to drive the LEDs have focused more attention on the thermal paths in the developments of LED power packaging. The l...

Open-Hole Size and Thermal Cycling Effects on Mass Loss and Surface Degradation of Polymer Matrix Composites

Degradation is a common problem for polymer matrix composites (PMCs) under low thermal cycling conditions. This paper investigates the effects of low thermal cycling on total mass loss (TML) and surface degradation of PMCs. Unnotched and open-hole specimens were weighed before and after low thermal cycling. The total mass loss and surface degradation of the specimens were studied over 250 cycle...

TherMal siMulaTion and characTerizaTion opTiMizes leds for auToMoTive applicaTions

Effect of Thermal Properties of Die Attach Materials on Performance of High Power Blue Leds

InGaN-based High Power blue LEDs exhibit a maximum light conversion efficiency of 40%, which decreases further at high drive currents. Thus, more than 60% of the electrical input power is dissipated as heat in an LED chip, leading to a rise in the junction temperature of the LED. Junction temperature has a significant impact on the light conversion efficiency of the LEDs. Also, it reduces LED l...