Calibration - How to display the circle Image

[fschiffers]

Hello,

first off: This is a great package and outstanding research! Thanks for putting all the work in making this open-source which really great documentation!

I am looking at " https://github.com/computational-imaging/neural-holography/blob/main/utils/calibration_module.py "

I haven't found any function that displays the binary pattern of the circles. I assume we are supposed to create and capture this image by ourselves. Is this correct?

Second - since the SLM is configured as phase-only, I believe that a binary pattern with circles should not provide a clear image of the binary pattern when observed with the camera. I was wondering if you have used a polarization filter to operate the SLM in intensity-only mode to capture a clear image for the tomography and afterward switch back to phase-only mode?

Thank you for your time!

[evanypeng]

Hello,

first off: This is a great package and outstanding research! Thanks for putting all the work in making this open-source which really great documentation!

I am looking at " https://github.com/computational-imaging/neural-holography/blob/main/utils/calibration_module.py "

I haven't found any function that displays the binary pattern of the circles. I assume we are supposed to create and capture this image by ourselves. Is this correct?

Second - since the SLM is configured as phase-only, I believe that a binary pattern with circles should not provide a clear image of the binary pattern when observed with the camera. I was wondering if you have used a polarization filter to operate the SLM in intensity-only mode to capture a clear image for the tomography and afterward switch back to phase-only mode?

Thank you for your time!

Hi there,

Sorry for the delayed response. And thanks so much for your interest in our work.

For calibration dot patterns (as shown in our supplement), you could use any programming/software to generate the pattern and then use ASM to generate the hologram to display. Thus, we didn't include the pattern in the GitHub. Then you just need to tune the parameters in the calibration module. We leave this to readers' creativity.

We didn't use an extra polarization filter. The homography was acquired using the same setup as the actual display. Note that even though it would be a binary dot pattern (target), the hologram to display is still phase-only.

Hope this helps resolve your questions.

Cheers,
The authors.