LED Multiplexer Brightens Up Medical Device Market

BREAKTHROUGHS

ZoroLight combines red, green, and blue LEDs to produce white light, providing more lumens than white LEDs do.

The lights of bulky, heat-generating, bulb-based illumination sources are dimming compared with compact light-emitting diode (LED) systems that can last 10 to 20 times longer. Recognizing that few LED multiplexing modules were available to OEMs, Bookham Inc. saw the light at the end of the optical filter tunnel. Rather than using lenses to capture light in free space, it has designed its LED module to trap light in a tunnel of highly reflective dielectric-coated surfaces that are geometrically optimized for efficient light collection and filter performance.

The ZoroLight LED multiplexer uses proprietary Advanced Energetic Deposition dielectric thin-film optical coating pro­cesses and Z-filter combina­tion optics. “We believe we are the only company to offer a com­pact device that combines a filter and LED light source solu­tion bright enough for OEM ana­lytical applications,” says Ben Standish, product line manager, thin films division. Requiring less space than traditional free-space LEDs and xenon bulbs, the multiplexer is also less prone to accumulating dust and other contaminants that can compromise product performance, Standish adds.

Combining red, green, and blue (RGB) LEDs to make white light, ZoroLight multiplexing optics allow for color balancing and produce more lumens than white LEDs alone, Standish says. The pro­duct can be used instead of free-space lenses and dichroic color-combining filters used to generate RGB white light.

Using Luminus PhlatLight LEDs to output thousands of lumens at as many angles, the RoHS-compliant multiplexer can be used in medical products to provide visual illumination via fiber bundles and liquid light guides. Another potential application is as an LED light source for diagnostic analysis equipment.

“ZoroLight optics were designed to facilitate the use of LEDs in pocket-sized video projectors,” Standish says. “We have high-brightness designs optimized for use with [digital light processing] chips in video projection, heads-up displays, and other industrial applications. Many of these designs work equally well for medical applications.”

Ranging in length from 80 to 200 mm, the multiplexer is able to accommodate up to six LEDs and typically achieves a collection efficiency rate of 65 to 85%. Standish stresses that the company spent a considerable amount of time developing the technology’s core enabling optical filters—which are critical for attaining high efficiency rates. To meet the diverse needs of OEMs, the intensity and size of the multiplexer’s wavelengths are customizable. “Designs can be customized to include [ultraviolet]- and [near infrared]-wavelength LEDs in addition to visual wavelengths,” Standish adds.

Bookham Inc., Santa Rosa, CA
www.bookham.com