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Favorite laser-pointer color? (hurray for diodes!)

  1. 650nm (red)

    0 vote(s)
    0.0%
  2. 632nm (orange-red)

    0 vote(s)
    0.0%
  3. 532nm (green)

    33.3%
  4. 593nm (yellow) (yeah, right)

    0 vote(s)
    0.0%
  5. 473nm (blue) (costs more than a laptop...)

    0 vote(s)
    0.0%
  6. 1400 keV gamma DeathStar (tm)

    66.7%
  1. Mar 19, 2006 #1
    I'm giving a small talk soon, so I've decided I should probably have a pointer to keep things on track. However, there are too many colors available, it's overwhelming; I don't like making decisions. My thoughts:

    Red just isn't that cool anymore. The dot is small and not very visible by comparison (to green). I've heard that the 635nm red-orange is more visible than the longer-wavelength reds (but I haven't seen one myself) - and still cheaper than green.

    Also, they now also have wireless remotes with lasers built in - only available in red I'm afraid. You can change slides and control the laser with the same hand - efficient!

    Green is extremely visible and keeps peoples' focus right where it needs to be. Also makes me look cool.

    Red-Green This overpriced novelty from Thinkgeek is an accident waiting to happen - it has two lasers, one on each end of the pointer (like a double light-saber). Oops wrong button! There goes an eye.

    Yellow and Blue are overpriced and overrated. Just look at this chart http://en.wikipedia.org/wiki/Luminosity_function to see why.

    Gamma-ray DeathStar (tm) (link) seems like a nice complement to any powerpoint presentation. Drawbacks - gamma rays are hard to focus, the dot might be too big to be useful (anyone have experience with this?); also, I've been told humanoids don't see gamma rays that well - is this true?
     
    Last edited by a moderator: Mar 19, 2006
  2. jcsd
  3. Mar 20, 2006 #2
    Really, I like the old stick with the pointed rubber tip and the loop on the other end for hanging it up when not in use. The nuns used to use these when I was in grade school. They also had these cool huge compasses for drawing arcs and circles on the chalk board that had a rubber thing in place of the metal point, and which accepted a stick of chalk into a kind of collet that was tightened by pushing a metal ring up a slotted taper.
     
  4. Mar 20, 2006 #3
    Have you tried the new white laser pointer?

    [​IMG]

    It really helps to shine light on the situation.

    Dude, seriously. You officially have the geekiest poll. Kudos. :rofl:

    Man you and your fancy pants presentation. My physics 3 professor would show us old films on old projectors. It was great. It had no sound, it would go tuk-tuk-tuk-tuk as the film spooled. Man I miss those lectures. He had old slides from the 60's that were out of production.
     
    Last edited: Mar 20, 2006
  5. Mar 20, 2006 #4

    Hurkyl

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    I've found green to be awfully bright: it can be bothersome to look at the green point on the wall for a nontrivial length of time.
     
  6. Mar 20, 2006 #5
    It takes only a couple of seconds to point to a figure on a slideshow, which is the intended use. It's much easier to immediatly notice a bright green dot, than a dim red one.

    I agree, it's bothersome to stare at it for long.

    Hurray for me!
     
  7. Mar 20, 2006 #6

    Moonbear

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    I like those too. Oh, oh, oh, they also used to have those chalk holders with 5 slots for the music teacher to draw scores on the board, or if you just put three pieces of chalk, the regular teacher could demonstrate the penmanship lessons. I loved the big compasses...they usually had a pencil eraser stuck on them though, to replace the rubber tip that had worn off between the time you were in school and I was in school. :biggrin:

    When I did my post-doc, we had a long, bamboo pole to use for the screen that was too tall to use the smaller pointers on. I was never sure if I was giving a presentation or getting ready to go surf fishing. :rofl: That was before everyone had cell phones everywhere, but I imagine it would come in handy now to reach into the audience and thwack someone in the head if their cell phone started ringing. I'm sure the nuns who taught you in school would have also liked it for the gum chewers and note passers and whisperers. :biggrin: It just isn't nearly as fun to blind people with a laser pointer.
     
  8. Mar 20, 2006 #7

    Moonbear

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    The red ones aren't that dim or hard to see if they have fresh batteries in them. I have a red one that is strong enough to shine several houses down the street!
     
  9. Mar 20, 2006 #8
    How do you know? :eek:
     
  10. Mar 20, 2006 #9

    Moonbear

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    It was covered in the "pointing devices" unit of the "How to Torture Students" course every professor and teacher is required to take. :biggrin:
     
  11. Mar 20, 2006 #10

    Astronuc

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    :rofl: But it would be highly effective with obnoxious and annoying self-declared experts who don't know have a clue about the subject matter and spout off dribble anyway. :biggrin: How many kW are we talking about here?

    Or one could use arrange a spherical battery of them and induce fusion reactions in tiny bits of solid D2. :biggrin: But they would have to probably upgraded to MW's.
     
  12. Mar 20, 2006 #11

    BobG

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    A yardstick works just as well. They're also cheaper and make a better sound when you smack them down on a desk, provided you don't smack them so hard they break.

    In high school, we had a math teacher that broke his yardstick all the time. He had a closet with spare yardsticks along one side and broken yardsticks tossed on the floor.

    There were lots of other stories about this guy, as well. He drove a Cadillac and wore a lot nicer suits than the other teachers. The rumor was that he'd invested in Xerox early and was rich. He didn't need to hold a teaching job to make a living - he taught just because he liked to torture students.

    Actually, he was normally a nice guy, but had a tendency to publicly humiliate students that he found particularly frustrating, in addition to scaring them half to death with those damn yardsticks.
     
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