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Lens That Writes on Both HD-DVD and Blu-Ray
morpheus83 writes "Ricoh claims they have developed an optical component that reads and writes all disk formats -- Blu-ray Disc and HD-DVD, as well as DVD and CD -- with one pickup and one objective lens. The component is a 3.5-mm diameter, 1-mm thick round diffraction plate with minute concentric groves on both sides which function as a diffraction grating. Based on disc information the drive can identify which format disk is loaded, Ricoh's optical diffraction component adjusts the laser beam with its diffraction grating for each format and passes it to the objective lens."
...and when that dedicated licensed device dies or breaks? Then what?
Most consumers will get bit by DRM, but only after the fact when it is too late.
This kind of multi-numerical aperture diffractive lens has already been used in several DVD players for CD compatibility. As an example, check out this link.
Notice that you do not only need different numerical aperture lenses to read every format, you also need to generate lasers of the proper wavelengths. There are several solutions for this, but the easiest is to use three different laser diodes.
Actually, dispite what the misleading headline would like you to believe, this isn't the first to read both HD and BluRay, and TFA doesn't make that clam... It's the first to read both, and read CDs and DVDs too with a single head. That's the tricky part, as CDs and DVDs use a different wavelength than HD-DVD and BluRay. Prior to this, if you wanted backwards compatability, you needed a second lens.