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DLP4500: DLP4500 with HDMI - pattern exposure time

Part Number: DLP4500

Hello!

I am using a DLP4500 module without its LEDs, to project some patterns with a laser beam.

So far I was using the pattern mode with the GUI interface, connecting the module via the USB port. This allowed me to choose the exposure time of each pattern.

Now I am trying to control the DLP via MATLAB connecting it as a second screen via the HDMI connector. I am able to send the patterns, but I think the micro-mirrors are continuously oscillating between the parked position and the pattern one, because I hear a buzzing noise, that I didn't hear with the other mode (my guess is that being the DMD used as a second screen this may cause it to be refreshed at the refresh rate of a normal screen, but I do not know if this is the case). By the way, I'd need the mirrors to be stable in the pattern position, because I am using a pulsed laser. So the question is basically if there is a way to set the exposure time of the patterns, when I am operating in video mode via HDMI.

I am pretty new to this technology so I hope I made myself clear, in case you need more details let me know.

Thank you!

Regards,

Luca

  • Hi Luca,

    Are you able to confirm the DMD is behaving as expected by first using the normal illumination and the GUI? Once you confirm that works (probably with pattern mode via external video) it will be easier to see if the Matlab code or DMD is at fault.

    Thanks,
    Kyle
  • Hi Kyle,

    thanks for your answer.

    So I tried to connect the DMD via HDMI using the GUI, using pattern mode via external video, but it doesn't work (unfortunately at the moment I can't try with the normal illumination). I mean the GUI seems not able to communicate with the DMD if connected via HDMI, it always display the red color on the "connected" button (to try that I set "pattern sequence" as "operating mode" and then I choose "video port" as the "pattern source").

    Besides, the PC sees the DMD as a second screen because I can share the window with it, so the two somehow communicate.

    I hope this is enough to give me some help, otherwise let me know.

    Thanks again,

    Luca

  • Hi Kyle,

    I think I probably resolved the issue, I was not choosing the proper options in the pattern settings and this didn't let me choose the exposure and period time for the patterns. Should I have other issues I'll open another thread.
    Thanks a lot for your time.

    Regards,
    Luca
  • Hi Luca,

    Glad to know you could resolve the issue. Thanks for your interest in TI DLP Technology, have a nice day. 
    Thanks & Regards,

    Hirak.