Volumetric display - 3D images in the air

[pocaracas]

Ladies and Gentlemen, the future is approaching!

Volumetric displays will be a reality within my lifetime!

https://www.nature.com/articles/d41586-018-01125-y

The technique, described in Nature on 24 January1, works more like a high-speed Etch a Sketch: it uses forces conveyed by a set of near-invisible laser beams to trap a single particle — of a plant fibre called cellulose — and heat it unevenly. That allows researchers to push and pull the cellulose around. A second set of lasers projects visible light — red, green and blue — onto the particle, illuminating it as it moves through space. Humans cannot discern images at rates faster than around 10 per second, so if the particle is moved fast enough, its trajectory appears as a solid line — like a sparkler moving in the dark. And if the image changes quickly enough, it seems to move. The display can be overlaid on real objects and viewers can walk around it in real space.

[Angrboda]

This is gonna be great! It will make answering email and browsing the forum just so much better!

[Anomalocaris]

Ladies and Gentlemen, the future is approaching!

Volumetric displays will be a reality within my lifetime!

https://www.nature.com/articles/d41586-018-01125-y

The technique, described in Nature on 24 January1, works more like a high-speed Etch a Sketch: it uses forces conveyed by a set of near-invisible laser beams to trap a single particle — of a plant fibre called cellulose — and heat it unevenly. That allows researchers to push and pull the cellulose around. A second set of lasers projects visible light — red, green and blue — onto the particle, illuminating it as it moves through space. Humans cannot discern images at rates faster than around 10 per second, so if the particle is moved fast enough, its trajectory appears as a solid line — like a sparkler moving in the dark. And if the image changes quickly enough, it seems to move. The display can be overlaid on real objects and viewers can walk around it in real space.

Several problems I can see with this technology:

1. It seems to me to be able to manipulate the location of the particle truely freely, there needs to be 6 lasers That can reach it to move it in both direction on each of X,Y and Z axis. This means the device projecting the image will have to have laser emitting appendages, above, below, to the left, right and in front and behind the image. This make it somewhat cumbersome.

2. I m not sure if a laser that can heat a particle enough to move it rapidly in the air can be eye safe.

3. How long will the particle last under repeated propulsive heating by the lasers?

4. Can one particle truly be moved so fast and accurately that it can etch complete images within each 1/10 of the second?

5. How would a whiff of breeze affect the motion of the laser propelled particle? Or does this only work in a vacuum tank?

[pocaracas]

Of course!

Several problems I can see with this technology:

1.  It seems to me to be able to manipulate the location of the particle truely freely, there needs to be 6 lasers That can reach it to move it in both direction on each of X,Y and Z axis.   This means the device projecting the image will have to have laser emitting appendages, above, below, to the left, right and in front and behind the image.  This make it somewhat cumbersome.

Not handheld, gotcha!

2.  I m not sure if a laser that can heat a particle enough to move it rapidly in the air can be eye safe.

Near-visible... I'm guessing also near-Infrared. Aimed mostly upward, should be ok.

3.  How long will the particle last under repeated propulsive heating by the lasers?

Don't know. They don't say. They say they are using a cellulose particle.... like paper?

4. Can one particle truly be moved so fast and accurately that it can etch complete images within each 1/10 of the second?

Apparently, so. It's even almost fast enough for a 25fps camera to only pick up some flicker.

5. How would a whiff of breeze affect the motion of the laser propelled particle?  Or does this only work in a vacuum tank?

A breeze would disrupt the thing, but it doesn't seem to have to be done in a vacuum tank... just indoors, closed windows.