No measurable physical quantity is ever infinite. In other words, only theoretical concepts can be definitively labeled as infinite. But that is perhaps an epistemological claim that is unnecessary here. So let’s dive into the nitty-gritty of how visual ‘resolution’ is actually measured. As we shall see, the number of light sensitive cells in the retina does not tell us what the ‘resolution’ of the visual system as a whole is. In some circumstances our visual ‘resolution’ exceeds that of the eye considered in isolation.
Visual acuity  is the sharpness with which we can distinguish patterns of light on the retina of the eye. This depends on the exact location of the light falling on the retina.