Search results
Results From The WOW.Com Content Network
S cones respond most strongly to blue short-wavelength light, peaking at 420 nm, and make up only around 2% of the cones in the human retina. The peak wavelengths of L, M, and S cones occur in the ranges of 564–580 nm, 534–545 nm, and 420–440 nm nm, respectively, depending on the individual.
The distribution of rods and cones (and classes thereof) in the retina is called the retinal mosaic. Each human retina has approximately 6 million cones and 120 million rods. [ 8 ] At the "center" of the retina (the point directly behind the lens) lies the fovea (or fovea centralis), which contains only cone cells; and is the region capable of ...
The fovea centralis is a small, central pit composed of closely packed cones in the eye.It is located in the center of the macula lutea of the retina. [1] [2]The fovea is responsible for sharp central vision (also called foveal vision), which is necessary in humans for activities for which visual detail is of primary importance, such as reading and driving.
Visual phototransduction is the sensory transduction process of the visual system by which light is detected by photoreceptor cells (rods and cones) in the vertebrate retina.A photon is absorbed by a retinal chromophore (each bound to an opsin), which initiates a signal cascade through several intermediate cells, then through the retinal ganglion cells (RGCs) comprising the optic nerve.
The retina (from Latin rete 'net'; pl. retinae or retinas) is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs.The optics of the eye create a focused two-dimensional image of the visual world on the retina, which then processes that image within the retina and sends nerve impulses along the optic nerve to the visual cortex to create visual perception.
The macula (/ˈmakjʊlə/) [1] or macula lutea is an oval-shaped pigmented area in the center of the retina of the human eye and in other animals. The macula in humans has a diameter of around 5.5 mm (0.22 in) and is subdivided into the umbo, foveola, foveal avascular zone, fovea, parafovea, and perifovea areas.
The light circle is the optic disc where the optic nerve exits the retina. The visual system in the human brain is too slow to process information if images are slipping across the retina at more than a few degrees per second. [28] Thus, to be able to see while moving, the brain must compensate for the motion of the head by turning the eyes.
Size and location on the retina: The location of the test spot affects the dark adaptation curve because of the distribution of the rods and cones in the retina. [20] Wavelength of the threshold light: Varying the wavelengths of stimuli also affect the dark adaptation curve.