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Three Dimensional Images in the Air

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Re: Three Dimensional Images in the Air

#11

Post by jsmcgd »

alex_c wrote: post #6

Can anyone explain to a layperson what produces the actual "glow" in thin air? The best I can do on my own is that the laser beam(s?) is(are?) focused on a point and briefly converts some of the air at that point into plasma, which glows? (on its own? because of the laser?) How hot does that get?

I was thinking the same thing. Wikipedia tells us that a flame is visible at 525 °C (977 °F). (I don't know if this is relevant as they talk about a 'plasma' and not a flame.) This might sound too hot to be safe but it only has to be that temperature for a very short time so presumably the energy density doesn't have to be very high.

Re: Three Dimensional Images in the Air

#13

Post by jsmcgd »

13ren wrote: post #9

Help me, Hacker-News; you're my only hope Q. Does "scanning" have the same meaning as in "raster scanning", where you cover the area (volume) in a set pattern? If so, I would have thought a vector approach would work better here... Q. What is a "motor orbit"? " The linear motor system enables the position of the laser focal point to be varied by high-speed scanning of a lens set on the motor orbit. Incorporation of t…

I kept thinking of that scene in Star Wars too!

Instead of a raster or vector approach how about an array of lasers all with fixed focal lengths that project into a predetermined 3D viewing space? Kind of like a 3D LCD setup. Tbh they've probably already thought of these ideas. As Obi-Wan says: "Patience".

Re: Three Dimensional Images in the Air

#14

Post by 13ren »

jsmcgd wrote: post #13
13ren wrote: post #9

Help me, Hacker-News; you're my only hope Q. Does "scanning" have the same meaning as in "raster scanning", where you cover the area (volume) in a set pattern? If so, I would have thought a vector approach would work better here... Q. What is a "motor orbit"? " The linear motor system enables the position of the laser focal point to be varied by high-speed scanning of a lens set on the motor orbit. Incorporation of t…

I kept thinking of that scene in Star Wars too! Instead of a raster or vector approach how about an array of lasers all with fixed focal lengths that project into a predetermined 3D viewing space? Kind of like a 3D LCD setup. Tbh they've probably already thought of these ideas. As Obi-Wan says: "Patience".

I think that's a good idea, but wow too expensive! Why not have a laser for each voxel in 1000x1000x1000 space? :-) Seriously, that may be the kind of breakthrough needed for this research to be commercially viable.

Re: Three Dimensional Images in the Air

#15

Post by LogicHoleFlaw »

iamwil wrote: post #3

"The emission time of the laser pulse light is on the order of a nano-second (10-9 sec). Our device uses 1 pulse for each dot to that the human eye can recognize plasma emission by utilizing the after-image effect, and enables a 100 dot/sec display." Still not quite ready for prime time. 100 dots/sec isn't enough to make a display, but rather, a skeletal dot array.

It looks almost exactly like the dot-frame images of the Death Star in the original Star Wars films.

The more things change...

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