Increased display efficiency gives device manufacturers more freedom to design new, previously unfeasible, low power devices. By combining an energy efficient backlight design with an efficient light source, display powers can be lowered to levels where a power source other than alternating current AC mains becomes feasible. Examples of a USB powered monitor in the mainstream size, as well as a Power Over Ethernet POE All‐In‐One Thin Client/Monitor device are demonstrated with today's technologies as a combination of efficient LEDs, reflective polarizers and low power LCD panels.

Photon correlation spectroscopy (PCS) is routinely used to investigate the dynamics of colloidal particles undergoing Brownian motion. This technique is applicable to low-density colloidal suspensions in which the effects of multiple light scattering are minimal. We introduce a new low-coherence heterodyne PCS technique that allows direct investigation of colloidal suspensions of higher concentration than previously accessible with standard PCS. In this technique, low-coherence optical heterodyne interferometry is used tosuppress multiple light scattering, allowing preferential detection of single-scattering events.