Suppose that an imaging system samples a checkerboard image at 8 samples (pixels) / mm of the checkerboard. What should be the minimum size (side-length (mm) x side-length (mm)) of a square of the...

Suppose that an imaging system samples a checkerboard image at 8 samples (pixels) / mm of the checkerboard. What should be the minimum size (side-length (mm) x side-length (mm)) of a square of the checkerboard, which will not cause aliasing in the image?