The rapidly increasing rate of technology development means that one day's "high tech" product becomes almost mundane the next. But it also means that technology in its many forms has woven itself into the very fabric of our lives, involving almost every aspect of the daily routine, from the cars we commute in to work, to the computer games our children play at home. So it is that in the wake of the events of September 11, advanced technology is one of the first places we look for help with improving the security of our everyday activities. Even before the terrorist attack, x-ray imaging was used at airports to inspect our luggage for weapons; on the street, law enforcement officials used infrared imaging to monitor criminal activity at night; and at our country's borders, increasingly advanced identity documents made it more difficult to pass through with forgeries.
Optoelectronics technologies underlie many of these security endeavors. Optical data storage, for example, takes various forms, but one commercial system allows creation of sophisticated identity cards that cannot be counterfeited as easily as their predecessors (see cover and p. 81). Besides the identity information one typically associates with such documents, these optical memory cards have the capacity to carry—in digital form—biometric information about the owner, such as an iris scan or a fingerprint, and it is probable that biometrics will now be under increasing scrutiny to see if it can help protect secure installations (see p. 168). Detectors also are fundamental to many security systems, be they simply sensing the presence of an intruder, or imaging and recording a secure area when an intruder is present. Recent developments involving the workhorse of detection, the photodiode, are discussed by Eric Lerner (see p. 133).
For many individuals, another facet of feeling personally secure is financial stability and an upbeat economic outlook. Five rules to help companies weather the bad times are presented by Tom Werner, CEO of Silicon Light Machines (Sunnyvale, CA; see p. 77); while "Business Forum" author Milton Chang helps us look for our own silver linings . . . and perhaps to find our own sense of security (see p. 74).
Editor's note: The scale accompanying the tiny bull on last month's cover and in a "World News" article was labeled incorrectly. The correct dimension is 2 µm and not the 2 nm that was shown. We apologize for the error.