Start-Up's Incredible Shrinking Infrared-Laser Sensor

Infrared-Laser technology used to be too large and unwieldy for many practical applications. But that may be changing, if Daylight Solutions (Poway, CA) has anything to say about it.The company has developed a method for drastically decreasing the size of infrared-laser technology, which used to be confined to university laboratories. A small metal case with a sliverlike semiconductor chip in the center and two small lenses on either end, the sensor detects and measures chemical vapor. With an eye toward medical applications, the company hopes that its miniaturized sensor will be used to detect glucose in the breath, eliminating the need for diabetics to draw blood through their fingers.Daylight's lasers operate in the midinfrared wavelength spectrum, remarks Timothy Day, the company's cofounder and chief executive officer. "It's the color of heat. It's the color snakes can see." The lasers are manufactured in part using quantum-cascade semiconductor chips, which were developed by Bell Labs in 1992. Daylight's contribution—called external cavity quantum cascade laser technology—consists of a patented structure for the chips that will enable them to be employed for commercial products.In addition to developing a marketable sensor, the company has also learned how to run the laser sensors on batteries and make them tunable like a radio. Tunability will enable them to detect a range of molecules without the need for complex adjustments.Having shrunk the sensor from the size of a desk to the size of a fast-food hamburger container, the company hopes to miniaturize it even more. "I look at this as next-generation technology," comments Paul Larson, the company's cofounder and chief operating officer. "It's like going from the mainframe computer to the desktop."