OPT3101: OPT3101:SDK Calibration problems

HEENA TYAGI

Part Number: OPT3101

Hi Alex,

As discussed in the other thread: https://e2e.ti.com/support/sensors-group/sensors/f/sensors-forum/1100949/opt3101-sdk-calibration-problems/4091915#4091915

I have added metal shield to my design. I have completed all the calibrations.

After calibration, my internal crosstalk is 3.4 and illumination crosstalk is 74.4. I am loading my crosstalk values in flash location.

But i am still getting wrong distance readings.

With my target set to a fixed distance, the results i am getting are varying amplitude and varying distance with fixed target.

Also, the distance value doesn't make any sense. Can you help me with this?

Regards

Heena

over 3 years ago

0 Alex Bhandari-Young over 3 years ago

TI__Mastermind 25855 points

Hi Heena,

How does the metal shield connect to your PCB?

Best,

Alex

0 HEENA TYAGI over 3 years ago in reply to Alex Bhandari-Young

Prodigy 30 points

Hi Alex,

Thank you for all you help so far.

I have managed to generate relevant distance readings.

I just have a last question. The distance readings I am getting are little different from actual reading.

At an actual distance of 300mm, I am getting 100 mm or so.

What could be the reason for that?

Regards

Heena

+1 Alex Bhandari-Young over 3 years ago in reply to HEENA TYAGI

TI__Mastermind 25855 points

Hi Heena,

Good to hear you are able to make progress. Distance accuracy at first order will depend on your phase offset calibration, especially if it is a constant offset.

After that, all the calibrations could impact as well (over temp, crosstalk, etc).

Best,

Alex

0 HEENA TYAGI over 3 years ago in reply to Alex Bhandari-Young

Prodigy 30 points

Hi Alex,

Thank you for your help.

I have one more question. I noticed that when my light covers two different distance, the output distance is an average of those two distances.

Is there anyway I can resolve this averaging problem?

Regards

Heena

+1 Alex Bhandari-Young over 3 years ago in reply to HEENA TYAGI

TI__Mastermind 25855 points

Hi Heena,

This is a fundamental property of these type of systems. You would need to use a narrower field of view emitter to decrease the detection area or increase the reflectivity of your target relative to the surroundings. The "averaging" acts like a weighted sum by the intensity of reflected light.

Best,

Alex

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OPT3101: OPT3101:SDK Calibration problems