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NIST scientists create 'any wavelength' lasers

nist.gov

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Re: NIST scientists create 'any wavelength' lasers

#81

Post by dnnddidiej »

nine_k wrote: post #15
dnnddidiej wrote: post #11

Earlier quoted context omitted.

Genuine q: how close can you get to magenta with the rainbow?

What we call "magenta" is the sensation of both red and blue color-sensitive cells in the eye being excited at the same time. There's no single wavelength that produces this effect (unlike e.g. yellow). The closes you can get is violet, which looks faint to the eye. A rainbow gives you both red and blue; mute everything else, and you'll get magenta. That's what magenta pigments do when illuminated by white light (whi…

It never clicked before that yellow and magenta are snowflakes to each other in this regard. I thought they were equals, but magenta is more majestic!

Re: NIST scientists create 'any wavelength' lasers

#82

Post by com2kid »

TomatoCo wrote: post #64
da_chicken wrote: post #55

Earlier quoted context omitted.

I think it's important to remember that we're not perceiving some fundamental aspect of light. We're perceiving how the photosensitive portions of our retina convert light to stimulus, and how our brains construct a meaningful image from that stimulus in our mind. Like film photography doesn't happen in the lens or the world. It happens in that photosensitive chemical reaction, and the decision of the photographer.

It reminds me of how vinyl records are fairly lossy, but they provide a superior experience in some cases because those limitations have been accounted for during the mastering process. It's an entire pipeline from photomultiplier to recording medium to the inverse process and everything is optimized not for any particular mathematical truth but for the subjective experience.

Vinyls are sometimes preferred because people like white noise, same as tube amps.

Granted some CDs are mastered like garbage, and that led to some bad press for awhile. But you can master a CD so that it sounds exactly, as in mathematically exactly, as a vinyl record, if so desired.

It is also possible to make a digital amplifier that sounds exactly identical to vacuum tubes.

Humans have well and mastered the art of shaping sound waveforms however we want.

Re: NIST scientists create 'any wavelength' lasers

#84

Post by wyager »

The final frontier of display tech (as far as being able to elicit any physiologically possible eye response) is a pair of tunable lasers. You really can't go much farther than that for emissive displays! We're almost saturated (no pun intended) on useful resolution, so I expect color to be the next area of focus.

Re: NIST scientists create 'any wavelength' lasers

#85

Post by loudmax »

lwansbrough wrote: post #75

0.1nm please. It's x-ray lithography time!

I was thinking the same thing. The stuff ASML does to produce a light at exactly the right wavelength is bananas. Making of stream of molten tin, and shooting each droplet with a laser, twice! Then bouncing the light through a series of super high precision mirrors to capture just the right spread. If you can get a laser to produce your desired wavelength without all that complexity, that's a major breakthrough.

Re: NIST scientists create 'any wavelength' lasers

#86

Post by travisjungroth »

awesome_dude wrote: post #44
jcul wrote: post #42

Earlier quoted context omitted.

The whole idea of colour and light frequency is fascinating. These are just frequencies of light, but the subjective experience of them is so much more. And the whole thing of my perception of "red" or what I call "red" could be very different to someone else's subjective perception. But we would both call it red and associate it with the same thing, fire, love, heat, danger etc.

But also - colours don't exist without a name eg. Before Orange, there was only shades of yellow or reds

The name for the color doesn’t exist before the name. But, you can distinguish all sorts of colors you don’t know the name for. Look at a smooth color wheel or a wall of paint swatches.

Re: NIST scientists create 'any wavelength' lasers

#87

Post by travisjungroth »

jjmarr wrote: post #74

I'm excited for new displays where instead of RGB primaries that can only show a triangular subset of possible colours, we have dynamic primaries that can combine to show almost any colour.

I want all the colors! Give me the full spectral power distribution!

Re: NIST scientists create 'any wavelength' lasers

#89

Post by analog31 »

adzm wrote: post #24

Everyone talking about magenta and brown, but you can see an illusory color right now even without lasers! https://dynomight.net/colors/ behold, some kind of hyper-turquoise

I worked with a brown laser when I was in grad school. It made a couple of brown spots on the wall by accident.

Re: NIST scientists create 'any wavelength' lasers

#90

Post by tclancy »

jagged-chisel wrote: post #43

The "shrinking" circle: I did as asked and clicked the image to see the animation. I saw no shrinking. My eyes did fatigue and I saw the border between the red and green become a blurred gradient. What should I have experienced?

You have to not blink too much or it resets the effect. After about a minute, the intense blue shows up around the red. And I say that as a man who has yet to see anything in a Magic Eye poster after a half century of what some would call life.
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