It seems as if every telecommunications-related article I have read recently opens with a reference to our society's current "insatiable demand for bandwidth"—or words to that effect—before going on to highlight some aspect of this demand and its consequences. The fact that this phrase and other similar ones have become clichés, regardless of the particular magazine or Web site in which they appear, underscores the very real impact that developments in telecommunications technology are having in every aspect of our lives. Recently, for example, I read an article previewing upcoming changes in automobile design that described a system for delivering real-time e-mail text messages to drivers via a head-up display on the windshield. A scary thought perhaps, but a great example of how we are all apparently moving toward being "totally connected." A direct result of this trend is clearly evident in Part II (diode lasers) of this year's Annual Review and Forecast of the Laser Marketplace, which begins on p. 70. Telecom applications were responsible for more than 75% of last year's overall laser market revenue growth. Notes contributing editor Bob Steele, "It is difficult to describe developments in the telecom market without resorting to superlatives."
The cutting edges
Another major market for lasers is materials processing, which is only just beginning as far as diode lasers are concerned. But a better understanding of beam quality and higher powers will spur further growth. Newer diode-based systems targeted at the industrial marketplace can embody variable (zoom) optics that allow the system to address a range of applications—such as cutting, marking, and welding—with maximum efficiency (see p. 117).
Away from the major laser markets, optoelectronics (OE) offers an even broader range of applications possibilities. A major trend in imaging is the gradually increasing level of integration—sensing elements are being fully integrated with data-handling elements—which makes processing a captured image much more efficient than previously. Such an integrated vision system potentially can address some very specialized applications (see p. 101). Meanwhile, in this and other OE fields, fabrication processes are continually changing. A new production technique for optical coatings unifies thin-film deposition and microlithography to allow multipatterned arrays of different optical filters on a single substrate for such applications as dense wavelength-division multiplexing (see p. 109)—which brings us right back to dealing with society's voracious appetite for more bandwidth!