Can DLP light commander be operated in terms of bitplanes?

Baoqing,

Welcome to the DLP & MEMS E2E forum.

Yes, it is possible to use the DLP LightCommander in the structured light mode (repeated pattern set). The LightCommander Control Software (GUI) allows projects to be defined and controlled. 8-bit patterns can run as fast as 716 Hz. 1-bit patterns can run as fast as 5000 Hz.

TI does not provide Labview code or interface. It is possible someone else has implemented this.

Please see this previous thread;

http://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/387/t/181290.aspx

Dear Baoquing,

Are you trying to update the each bit-plane individually?

Perhaps you have tried - the C200 of the DLP300 accepts 24-bits input. As Pascal noted, you can render the 24-bits as individual bit-planes. The fundamental limitation is that you must apply all bit-planes during every sync period. 

We provided a DLL file API in our X3-PM55 implementation so you can create your own Labview or Matlab solution. We can provide a programmable synchronization or trigger signal. Please contact us if you need further information.

- Adam

Keynote Photonics

Hi Pascal,

Thank you very much for your reply.

I tried to setup the DLP GUI. But I find that in structure light mode and DVI connection I cannot change the Frame Rate higher than 60, the max frame rate is 60. (However under Static Image Buffer data source I can change the frame rate. But Static Image Buffer is not what we want).

Is it possible to exceed the frame rate  60hz for DVI data source? 

Actually my problem is exactly the same as described here

http://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/387/t/181290.aspx

Either with video mode or structure light mode so far I can find out a way to run the projector faster than 60Hz.

Dear Adam,

I get the rough Idea that this specific projector can run 'faster" in the way we expect.  But far as we have got a light commander we have to first think about use that.  will consider C200 as another choice.

Thank you for your suggestion.

Baoqing

Baoqing,

You point to a thread that answers your question: 

http://e2e.ti.com/support/dlp__mems_micro-electro-mechanical_systems/f/387/t/181290.aspx

The video frame rate over HDMI (DVI) is in fact limited to 60Hz. However, the way that the LightCommander interprets each frame in the structured light mode is what makes the higher bit-plane rates possible. Each frame in video mode is RGB888 (24 bit color). However, in external (input from HDMI or from expansion port) structured light mode, the DLPC200 uses the 24 bits in an entirely different way than RGB888. It looks at the 24 bits in such a way as to assign groups of bits to bit-planes (structured light frames) according to the structured light mode setting - 8-bits or 1-bit.

If you select external 8-bits, then the video frame is interpreted such that each 8-bits across the full 24 bits is treated as an 8-bit gray scale pattern. Therefore, there are (up to) 3 8-bit gray scale pattern per video frame. If the frame rate is set to 60 Hz, then you will get 3x60=180 8-bit gray scale patterns per second.

If you select external 1-bit, then the video frame is interpreted such that each bit across the full 24 bits is treated as a 1-bit (B/W) pattern. Therefore, there are (up to) 24 1-bit (B/W) patterns per video frame. If the frame rate is set to 60 Hz, then you will get 24x60=1440 1-bit (B/W) patterns per second.

I hope this helps.

Hi Baoqinq,

We've been able to support a faster frame rate on the Port2  frame rate higher that 60 Hz on our X3-PM55 board, though we have to limit the number of bits/pixel rendered on the DMD. This port is connected to our FPGA. I know this doesn't help you out of your present dilemma but wanted to let you know it is possible.

Regards,

Adam
Keynote Photonics