• TI Thinks Resolved

DLP4710EVM-LC: Vertical Pattern shifted

Intellectual 255 points

Replies: 14

Views: 256

Part Number: DLP4710EVM-LC

Hello TI,

I use EVM to project 45 patterns (24 vertical patterns and 22 horizontal patterns). I found vertical patterns are shifted (please see below pictures), could you please help me to solve the problem?

Thanks!

Derlin 

  • Hello Derlin,

    What is the size of the image you are uploading?

    Thanks,

    Kyle

  • In reply to Kyle Rakos:

    Hi Kyle,

    These png files are about 80kBytes.

    Thanks! 

    Derlin

  • In reply to Derlin Chow:

    Hi Derlin,

    Can you please try by flipping the pattern and see are you seeing the shifted pixel on the same side ?

    Thanks,

    Navneet

  • In reply to Navneet Singh:

    Hi Navneet,

    Please see attached screenshots showing two similar patterns (white to black/black to white except center thin black line  ) and their projection respectively.

    The lower image of each screenshot is image (or pattern) 2 and the upper is image (pattern) 3. Let's look at pattern 2, the number of wider bars on the right hand side of center thin bar on the pattern file is "15", but projected pattern shows "16". The number of wider bars on the left hand side of center thin line on the pattern file is "16", but projected pattern shows "15"  

    I believe EVM starts the patter in the center of the image and causes the pattern shift in half. This does not happen to horizontal bars since it makes no different where to start for horizontal patterns. 

    In addition, I read through many posts on this forum, I think my problem is same as below post

    e2e.ti.com/.../3065313

    Thanks!

    Derlin

  • In reply to Derlin Chow:

    Hi Navneet,

    I attached my vertical pattern files, could you please try them on your end?

    Pre and post dark time: 1000us

    Exposure time: 8000

    Color: RGB

    Thank you!

    Derlin

    Thanks!

     

  • In reply to Derlin Chow:

    Hi Derlin,

    I will check and get back to you soon.

    Thanks,

    Navneet

  • In reply to Navneet Singh:

    Hi Derlin,

    we are trying to make a setup here and will try to reproduce the same.

    It is gonna take some more time as i am going on vacation, my colleague is currently looking in to this and we will get back to you with our findings very soon.

    Thanks,

    Navneet

  • In reply to Navneet Singh:

    Hi Navneet,

    No problem. I am looking forward to your answer!!

    Derlin

  • In reply to Derlin Chow:

    Derlin,

    Thanks for your patience on this issue. We will provide a response as soon as we run test on our setup.

    Regards,

    Philippe Dollo

  • Hi Derlin, and Navneet.

    I think it is not shifted, but merged with other pattern, maybe the next one.

    I have very similar issue, sometimes EVM resolved itself without any answer :)).

    Now I am facing with mixing patterns as attached picture:

    Some phenomenons I observed:

    1. Only vertical and horizontal patterns => Works fine

    2. Mixing with Diagonal pattern => got above issue

    3. Generating Bin file:

        - Only vertical and horizontal patterns (I have 34 of them in total):  firmware Bin file size: 1.4MB

        - With above Bin file, add diagonal pattern (8 patterns more): firmware Bin file size: 4.5MB

    All patterns are generated in 1bit format, file size is 129kB.

    I dont understand why it happened in this way?

    Any input for this issue would be appreciated.

    Thank you.

    Best regards. Bui Quang Lam