Close

3D Glasses

A project log for prism laser scanner

bringing additive manufacturing to the next level

hexastormHexastorm 07/12/2019 at 18:310 Comments

In my previous post, I outlined how a transparent polygon scanner can be used for detecting eye diseases.

Logically, a transparent polygon scanner can also be used in 3D glasses.  Reflective polygon scanners are used for creating a screen in a laser TV.  A scanning prism can also be used to create a Laser TV; especially if the configuration is used as described in the wide scan angle log..

A lot of companies are active in 3D glasses; e.g. Google Glass, Magic Leap, Oculus and Hololens.

Colors are created in a laser TV by  coupling three lasers of different wavelength and optical power in the same bundle.

For 1080p at 100 hertz. you would like something on the order of 100,000 lines per second.

At 30.000 RPM and 8 sides prism you have 4000 lines per second.

This is not enough;

Option 1:  Miniaturization
Scale down the size of the prism, this will make it easier to spin it at high speed. The angular momentum drops due to lower mass and radius, which implies lower energies at a fixed RPM. The fastest spinning disk ever made at 600 million RPM is also small.

Option 2: Fiber array
You could use 20 fibers where each fiber has 3 lasers but once you have multiple lasers per color, then you have to get everything very precisely aligned with 6 degrees of freedom. This is a tough problem with just 3 colors. Let alone 20 fibers with 3 laser colors.

Option 3: Increase the number of facets
There are prism which have 72 facets and can be spun at 70.000 rpm  (see roadrunner).

Option 4:  Optical transformation
Project 1920x1080x100 pixels but divide it over 4000 lines where each line has 51840 pixels. This would however require a small spot for a 20 mm long line  of something like 385 nm which seems unfeasible

In summary, the problem seems quite hard. A polygon would be needed that can be spun at say <200000 rpm. The second in the other direction can then be created by a second prism.
Still there are many companies that believe in this see Scanning Mirror Devices Patent by Apple Computers.
I claim everything Apple claims; with the fancy pictures and all... major difference; using a scanning prism!

Discussions