Their time has come

In a recent posting on his Opto Insider blog, my colleague Tom Hausken from Strategies Unlimited (Mountain View, CA) stated: "The time for mid-infrared lasers has finally come ... change is coming with new solutions, new applications, and new companies." He noted that there are currently more than 50 companies now selling lasers or OPOs and OPAs [optical parametric oscillators and amplifiers] emitting in the mid-infrared (IR). The appeal of this wavelength range is that many gases exhibit "signature" absorption bands in the mid-IR and these signatures can be put to good use in spectroscopic scanners designed for industrial gas detection and monitoring. In one example, a commercial quantum-cascade-laser-based gas-detection engine is being developed for industrial applications (see page 33).

Terahertz waves are another region of the electromagnetic spectrum where the specific spectral properties of gases and solids promise unique detection opportunities, especially when combined with terahertz imaging—terahertz waves can penetrate a wide variety of nonconducting materials. Potential commercial applications include security screening, nondestructive testing, and biomedicine. Among the hurdles to jump before terahertz spectroscopic imaging can be successfully deployed on a commercial basis is acquisition time. To this end, researchers in Rome, Italy are working on terahertz detectors with microsecond response times fabricated by lithography, anticipating future integration into monolithic focal plane arrays (see page 51).

In another blog posting, Tom discusses the last decade's five best market trends in photonics. Among them, he lists the "green revolution," specifically solar and light-emitting diode (LED) technologies. The need for energy efficiency is driving a sea change in lighting technology, with the result that the market for high-brightness LEDs grew 68% last year, according to Strategies Unlimited. Characterizing the performance of all those devices at various points in the manufacturing process is an essential element of cost-effective volume production. Optical testing ensures the LEDs meet end-user requirements across a range of operating parameters (see page 55). LED lighting is definitely another technology whose time has come.