Just a few years ago, as part of an assignment to organize a spectroscopy conference on the California coast, I solicited contributions from local laser manufacturers to defray the cost of graduate student attendance and to enhance our social hours. Sponsors were invited to distribute sales literature in the back of the hall, but they were not supposed to do laser demos. So I was surprised to see people gathering around the Spectra-Physics sales rep who was holding something smaller than a shoe box in his hand. It was plugged into an ordinary 110-V wall socket, and a familiar-colored green light came out the end!
"What is that?" I asked.
"Our new diode-pumped Nd:YAG laser," he replied.
"But," I stammered, "that can't be a laser! Besides, you're not supposed to do product demos here."
"It's a laser, all right, but it's not really a product," he assured me. "We just put a doubling crystal in front to make the beam visible." Then he handed me some literature that introduced me to the world of diode-pumped solid-state lasers.
Obviously this new technology has garnered more than casual interest. In the seven or so years since I saw my first diode-pumped laser, many other manufacturers have jumped into this rapidly growing market. In our most recent forecast of laser markets (see Laser Focus World, Jan. 1996, p. 50), senior editor Steve Anderson estimated that several thousand diode-pumped solid-state lasers, worth in excess of $40 million, will be sold this year. High-power diode-pumped visible lasers are available now, too. These devices are touted as replacements for ion lasers, especially in scientific applications such as pumping Ti:sapphire lasers; an article on p. 63 explains the latest technology from Spectra-Physics Lasers.
The microlasers described on p. 73 offer another novel approach to laser design. Palm-sized, yet diode pumped, these lasers have potential—especially at visible and UV wavelengths—to be used in many applications.
Back to Basics is back
Detectors may be one of the most pervasive optoelectronic devices both in and out of the laboratory. This month, we begin another Back to Basics series with articles describing photodetectors and the myriad applications evolving around them. In the introduction on p. 95, physicist/writer Eric Lerner summarizes some detector applications; subsequent articles will categorize detectors by spectral region and device complexity and explain operating principles for various detectors.