diffraction
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Harvard makes distortion-free lens from gold and silicon, aims for the perfect image (or signal)
Imaging has been defined by glass lenses for centuries, and even fiber optics haven't entirely escaped the material's clutch. Harvard's School of Engineering and Applied Sciences might have just found a way to buck those old (and not-so-old) traditions. A new 60-nanometer thick silicon lens, layered with legions of gold nanoantennas, can catch and refocus light without the distortion or other artifacts that come with having to use the thick, curved pieces of glass we're used to -- it's so accurate that it nearly challenges the laws of diffraction. The lens isn't trapped to bending one slice of the light spectrum, either. It can range from near-infrared to terahertz ranges, suiting it both to photography and to shuttling data. We don't know what obstacles might be in the way to production, which leads us to think that we won't be finding a gold-and-silicon lens attached to a camera or inside a network connection anytime soon. If the technology holds up under scrutiny, though, it could ultimately spare us from the big, complicated optics we often need to get just the right shot.
Ricoh laser head reads/writes HD DVD and Blu-ray discs
While there is still doubt over if or when a Blu-ray and HD DVD capable drive will be available, Ricoh has created a single laser that is able to read discs in either format. Their new component will be able to read and write to Blu-ray, HD DVD, DVD and CD with one pickup and one objective lens. The 3.5-mm diameter, 1-mm thick round diffraction plate detects what kind of disc has been inserted, and adjusts to change the laser beam as necessary for the format. They'll be showing off the tech later this week at the International Optoelectronics Exhibition '06 in Japan.While both formats use blue lasers they record at different distances and widths, a single head that overcomes those differences could make a dual-format player cheaper and a more realistic possibility if licensing fees and agreements don't get in the way. Ricoh certainly doesn't think they will, saying this technology will "make it possible to build players and recorders for all formats which benefits consumers". That's the triple truth, although if this coming technology at all influenced Toshiba's conciliatory remarks recently is unknown.They see this technology becoming commercially available by the end of this year. It will only be available for playback devices initially, as a higher powered laser is needed for recording. Those of us waiting for a relatively inexpensive solution to the high definition format war will be waiting just a bit longer.
