We wouldn’t be the first to compare the optics of the eye to a camera. The eye is actually a satellite extension of the brain but it is much more complex. If you understand the interaction of the lens optics, the camera body, the film/receptor, aperture, and other basic photography concepts, you will have a better understanding of how eye floaters are seen and interpreted by the eye and brain.
A comparison of the optics of a camera and the eye
Unlike the static image created by a camera, eye floaters are a dynamic visual phenomenon that are interpreted by the brain’s visual cortex and the awareness of these floaters are influenced by the person’s personality type or other factors such as focus of attention to the floaters, vocational activities, ambient light, background detail, and other external factors.
A common complaint: Floaters while working on a computer
Depending on the location of the floater material in the eye, the shadow can be seen as soft vs. hard edged, distinct vs. vague. The mobility of the floater is influenced by the liquefaction (breakdown of gel to more watery fluid) of the vitreous as well as the amount of eye, head, and body movement. The awareness of the eye floaters also depends greatly on the visual task performed. Bright ambient light (e.g. daytime driving) and/or brightly backlit visual material (e.g. computer monitors will tend to accentuate the shadows.
Here is a combination illustration showing the position of an opaque object positioned in the middle of the eye. The dark disk toward the front of the eye represents the pupil opening (small opening in this example) The light rays enter the eye through a small opening and cast a fairly well-defined shadow onto the retina. The box to the right shows how it might be seen by someone looking out towards a plain white background.
Here is that same object but now the light is passing through a much larger dilated pupil such as at nighttime or when the doctor dilated the eyes with eye drops. Since the light is entering from a much larger opening, the shadows overlap. The light coming in from the periphery decreased the shadow in the center. The result is a much less prominent and less bothersome or distinctly defined shadow.
Your awareness of a floater (as well as treatability with the laser) depends on a multitude of factors: size, density, proximity to retina, size of pupil opening, central vs. peripheral location, and velocity and direction of movement. There is no simple test to determine if your eye floaters are treatable.
