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  • #31
    OK, Trivial Pursuit time.

    Who made the first LEDs, when and what colour?
    Brian (the devil incarnate)

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    • #32
      Dunno - though Nichia produced the first blue ones in... 1993 IIRC.

      AZ
      There's an Opera in my macbook.

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      • #33
        Sorry, not true. The first blue ones were quite a bit earlier than that. Anyone else?
        Brian (the devil incarnate)

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        • #34
          Blue dyed ones, maybe. But TRUE blue ones not.

          AZ
          There's an Opera in my macbook.

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          • #35
            No! TRUE blue. In fact, the very first ones were blue but the guy who made them was able to produce red and yellow later. I'll post the details below, if you want to know.
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            It was in 1907 that Henry J. Round published a short paper in Wireless World, entitled "A Note on Carborundum". He described the "puzzling emission of cold blue light" from carborundum detectors under certain conditions, usually when the catswhisker potential was very negative relative to that of the crystal. Some blue LEDs today still use carborundum, but the gallium nitride ones discovered by Shuji Nakamura of Nichia Chemical in 1992/3 are certainly more efficient.

            So LEDs, and especially blue ones are really 93 years old!
            Brian (the devil incarnate)

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            • #36
              OK. USEFUL blue laser LEDs

              AZ
              There's an Opera in my macbook.

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              • #37
                Originally posted by KvHagedorn
                To each his own, but I remember seeing an article online about an apartment lit entirely with LEDs.. just seemed like a purplish, unnatural, ghostly light to me. I would rather have my home lit by lights of a cooler temperature.. it feels much less stressful to me. I don't care for rooms to be lit with flourescent lighting either.
                "For every action, there is an equal and opposite criticism."

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                • #38
                  Thanks TX

                  I find the Vos Pad pretty hideous, actually reminding me of some of the excesses of the 1930s. However, I suppose the light can be adjusted to any colour, rather than some of the exaggerations illustrated. Two things are not mentioned: a) the cost and b) the light level (can you actually read small print when seated in the sitting room-cum-clinic.

                  I wonder whether anyone can actually live in a place like that
                  Brian (the devil incarnate)

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                  • #39
                    Yep, that's the one. Who wants to sleep here?

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