The Epson E-TORL UHE Projector Lamp Advantage

While most new digital projectors ship with a lamp manufactured by either Philips, Osram Sylvania, Ushio, Phoenix or Panasonic, Epson has forged it's own path with its UHE lamp for Epson projectors.

Epson calls their lamp the "Twin Optimized Reflection Lamp or E-TORL".

To improve optical efficiency Epson engineers focused on tweaking the reflector of the traditional UHP (Philips), P-VIP (Osram), etc projection lamps. The first change was from the common parabolic reflector to an elliptical shape. The parabolic curvature allows, according to Epson, a significant portion of light to be "reflected away from the light path of the optical unit." The misdirected light results in some loss of effective projection brightness.

The elliptical shaped reflector designed by Epson reduces light "loss" and increases the optical efficiency of the lamp.

In addition, Epson added a sub-reflector to their E-TORL lamp. This reflector, according to Epson, "further improves efficiency by collecting and channeling the light from the area in the center of the lamp into the optics."

Epson calculates the net result of these reflector changes results in a 20% light projection efficiency improvement.

Another change Epson made to the conventional projection lamp incorporates an air gap between the reflector and the burner. This layer of air results in a cooler operating lamp and lengthens rated lamp life. Epson UHE lamps generally have a 4000 to 5000 hour life expectancy compared to a 1500 to 3000 hour rated life for other projector lamps.

If should be noted that the Epson UHE (E-TORL) lamp uses the same metal halide burner technology as UHP, P-VIP and other projection lamps. The conventional parabolic reflector lamps still drive the vast majority of projectors and provide excellent optical performance. Epson is betting a 20% optical efficiency improvement and longer lamp life with E-TORL lamps will help push buyers of projectors to the Epson brand.