# 1000 Hz+ refresh rate displays/ projectors? (for making volumetric displays)

I have found only few volumetric displays for the kind of effect I'm looking for. They can be divided by two characteristics into two separate groups each: rotating or moving screens, and moving screens with a high refresh rate projector projecting on them or high refresh rate rotating displays.

EDIT: I have now come to the conclusion that projection-based rotating screens will work while displays/led arrays will not. Unless I can be finally be told whether LCD/other displays can be ran at few thousand Hz themselves, leaving the controller aside. And LED arrays are too low resolution for my goal (DMD chips projecting 600x600 pixels is fine, 128x128 leds is bulky for such rotations and low-res).

“Swept motion volumetric projected screens” seems the most promising.

if you want a 24 Hz refresh rate of a volume (a 3d frame), you can rotate a 2d screen 24 * 180 times. That's over 4000 frames per second. 180 is the number of "slices" (2d displays) the volumetric display has. Its one for each 1 degrees. 180 because 180 degree rotation of a 2d display is needed to create a 360 degree volume:

Finding out how to control a 900 RPM motor is easy, displaying 4000 frames each seconds... not so much. From the various articles I've found on the internet I now have only a basic idea how to build a real volumetric display. I will link to relevant sites below. 3 DMDs/DLP chips (for R,G,B) have been used before each projecting 1 bit monochrome dithered image.

1) Perspecta. In it a "high speed projector" projects 198 768x768 pixel "slices" at 24 Hz on a rotating screen (rotating at 730 rpm).

The projector is a "5kHz MEMS-based".

The slices are projected at approximately 6000 images/ s by a group of three Digital Micromirror Devices, microelectromechanical systems- (MEMS-) based spatial light modulators (Texas Instrument, Inc. Plano, Texas).

A very simplified illustration of how it works:

2) “angled mirror” type: http://gl.ict.usc.edu/Research/3ddisplay/

Simplified illustration: https://i.imgur.com/2ITO7ta.gif

While I have found such MEMS ( DMD chips ) there is literally no ready affordable board for controlling them. TI and partners only sell boards for video projector manufacturers, 3d printing companies and similar and therefore are extremely expensive for what they do and what a university student or hobbyist can afford. Are there any? http://www.ti.com/tool/dlplcr4500evm http://www.ti.com/tool/dlpd4x00kit

This last project is especially interesting since it is using a relatively cheap $600 1440 Hz projector from Texas Instruments. But I am unable to contact the author. I have some questions and doubts that his project was successful (seeing no final video to prove it worked). For one thing 1440 Hz seems too slow, it would only allow 12 fps and 120 slices for each volume and I'm not sure if in this case either persistence of vision will work and 120 slices instead of 180 will provide a convincing volume. And perhaps there are better options with other projection technologies? I can't find any mention of LCD projection. What about sending monochrome video data to a out-of-the-shelf video projector or modifying such a projector to work that way instead of these expensive "evaluation modules" Texas Instrument sells? So to sum up all my questions: 1) Is there a cheap ($600-700) way to project a monochrome video at few thousand Hz?
2) What can I use? Can a off-the-shelf video projector be made to work that way? How?
3) If not, can anyone help with building a control board from Texas Instruments DMD chips, DLP controllers and DM365 (TMS320DM365 Digital Media System-on-Chip (DMSoC)) which are used by the porfessional boards and are cheap by themselves?