• State TI Thinks Resolved
  • Locked Locked
  • Replies 2 replies
  • Answers 1 answer
  • Subscribers 32 subscribers
  • Views 1177 views
  • Users 0 members are here
Support feedback
Options
Options
Related

This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

OPT8241 Saturation & dynamic range

Pierre Cottin
Prodigy 90 points
Other Parts Discussed in Thread: OPT8241, OPT9221

Hi,

When acquiring a range image with OPT8241, is there a way to check if a pixel data is saturated or invalid and then reject distance measurement accordingly?

What kind of signal dynamic range could I expect while maintaining a valid distance measurement?

Thanks.

Pierre Cottin

  • 0
    TI__Intellectual 2030 points
    Pierre,

    With the default settings, there is no indication of saturation. But you can set saturation_threshold to a typical value of '1200' to configure the TFC (OPT9221) to declare all pixels which have a ambient value less than or equal to '1200' as saturated. The flag data for each pixel will have the saturation information. Refer to the description of "FLAG BIT" in the datasheet. There is no one setting that works perfectly for all systems. For a given system you can figure out if the pixels are saturating by the following method -
    - Reduce the distance between camera and target till you see a drop in amplitude. (Amplitude increases with reducing distance till the pixels get saturated)
    - At that position, configure the saturation_threshold register to make sure that the saturated pixels indeed show up as saturated in the flag data. The value you obtain should be typically about '1200'

    For checking the typical dynamic range you can achieve for a given configuration, we would recommend that you try the system estimator tool here - www.ti.com/.../sbac124 on this page - www.ti.com/.../toolssoftware. The estimator tool is the best place to get started as the dynamic range depends on several system configurations as well external conditions such as number of sub-frames, quads, modulation frequency, HDR (High dynamic range) setting and the presence of ambient light.

    Regards