Early in August, The New York Times ran an article proclaiming the end of the picture tube. Cathode-ray tubes (CRTs) are "heading for the dustbin of history much faster than anyone expected," wrote our colleague and contributor Eric Taub. But unlike a dead-end technology like the SACD — whose death I proclaimed in my last column — many characteristics of the CRT live on in HDTV systems.

Way back in 1940, Vladimir Zworykin, a pioneer in the development and commercialization of television, said in his early textbook on TV that the CRT "will continue to keep step with the inevitable advance of television standards." He would probably be as impressed with the technology's 66-year-plus longevity as I am. Zworykin would also be the first to recognize those capabilities and limitations of picture-tube technology that have survived into the HDTV era.

Take scanning, for instance — the process by which an image is disassembled in a camera and reassembled on a TV tube. The concept of line-by-line scanning was fundamental to early television because it was used in both the image sensors (such as Zworykin's Iconoscope, a sort of picture tube in reverse) and in display CRTs. We still speak of pictures being built up of scan lines, even though solid-state CCD image sensors in video cameras, as well as all fixed-pixel display technologies (LCD, DLP, LCoS, plasma), don't have to scan the image line by line — they all sense or display an entire frame all at once. In principle, you could directly hook up a 1080-line CCD camera to a 1080-line fixed-pixel display on a pixel-by-pixel basis, though it would take a couple of million cables! Other CRT-derived systems similarly survive into HDTV, including interlaced video encoding and the precise shades of the red, green, and blue primary colors for HDTV (derived from CRT-phosphor colors).

While CRTs won't be missed by anyone with a small apartment, there are people already very concerned about the eventual shutdown of CRT production lines — those whose profession requires them to monitor video quality for transmission or mastering purposes. Almost all of these folks are now making decisions about video quality using relatively small CRT monitors. This isn't a bad thing, since no fixed-pixel technology can reproduce the whole video dynamic range quite as smoothly as a CRT with its truly black blacks.

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