Those kind of light receptors don't have the lenses that cause our eyes to flip the image. They are omnidirectional and usually not even on the surface of the c

Those kind of light receptors don't have the lenses that cause our eyes to flip the image. They are omnidirectional and usually not even on the surface of the critter. Just a small bag of rhodopsin that triggers a nerve to depolarize. I think the geometric arguments in the article make sense in that context as well, the same way they would for a chemotactic or pressure sensor.