Frequency Domain and pixel size

[houssain95]

TL;DR Summary

what is the relation between pixel size of CCD camera and field of view in frequency domain?

I'm developing an off-axis digital holographic camera. Initially, I employed a CCD camera with 6.7-micrometer pixels and successfully observed the first-order interference pattern in the Fourier domain. However, when I switched to a CCD camera with smaller pixels (1.67 micrometers), the first-order pattern vanished. Can you explain why this occurred?

 

[Baluncore]

Welcome to PF.,

Maybe the smaller pixel camera sensor was also smaller overall, so the sensor array fell within the first-order pattern. You unintentionally cut the low spatial frequency information by using a narrower camera.
What was your test image.
What did the first-order pattern look like?
What were the outer dimensions of the image arrays?