A more substantial problem is that diffraction limits the effective resolution of an optical system to well above the size of each of these pixels. This is a problem with current sensors at narrow apertures; lenses exhibit a measurable loss of sharpness, typically f/11 and up, because the airy disks expand as the aperture contracts. With hugely dense sensors like this, though... plugging some numbers into a website that explains the whole situation suggests that you'd need to shoot with apertures than f/1.8 to get circles of confusion smaller than the size of a single pixel.
That's right--even "fast" f/2.8 lenses are limited by physics to never being able to project detail onto individual pixels. You could potentially add a deconvolution stage in software to recover additional sharpness, but not in hardware.
Another thing. Do the math: the pixels are 2.1 micrometers square. Compare to trichromatic human vision, which detects red light peaking at 564 nanometers, 0.564 micrometers. The size of a pixel is within a factor of four of the wavelengths they measure. Staggering.
Glass isn't the problem. We need new laws of nature, since we're near the edges of the ones we have now.
"Protozoa are small, and bacteria are small, but viruses are smaller than the both put together."
