Proceedings Article | 1 March 2013
KEYWORDS: Convection, Cooling systems, Aluminum, Radiative transfer, Flat panel displays, Electronics, Reliability, Resistance, Light emitting diodes, Display technology
Flat panel displays are conventionally cooled by internal natural convection, which constrains the possible rate of heat
transfer from the panel. On one hand, during the last few years, the power consumption and the related cooling
requirement for 1080p displays have decreased mostly due to energy savings by the switch to LED backlighting and
more efficient electronics. However, on the other hand, the required cooling rate recently started to increase with new
directions in the industry such as 3D displays, and ultra-high-resolution displays (recent 4K announcements and planned
introduction of 8K). In addition to these trends in display technology itself, there is also a trend to integrate consumer
entertainment products into displays with the ultimate goal of designing a multifunction device replacing the TV, the
media player, the PC, the game console and the sound system. Considering the increasing power requirement for higher
fidelity in video processing, these multifunction devices tend to generate very high heat fluxes, which are impossible to
dissipate with internal natural convection. In order to overcome this obstacle, instead of active cooling with forced
convection that comes with drawbacks of noise, additional power consumption, and reduced reliability, a passive cooling
system relying on external natural convection and radiation is proposed here. The proposed cooling system consists of a
heat spreader flat heat pipe and aluminum plate-finned heat sink with anodized surfaces. For this system, the possible
maximum heat dissipation rates from the standard size panels (in 26-70 inch range) are estimated by using our recently
obtained heat transfer correlations for the natural convection from aluminum plate-finned heat sinks together with the
surface-to-surface radiation. With the use of the proposed passive cooling system, the possibility of dissipating very high
heat rates is demonstrated, hinting a promising green alternative to active cooling.
