Blind Spot vs. Yellow Spot
Key Differences
Blind Spot
Also known as scotoma, it is an obscuration in the visual field. A blind spot is a region in the visual field present on the retina which corresponds to the lack of light detecting photoreceptors on the optic disc where the fibers of optic nerve passes through the optic disc. Because Blind spot have no cells for the detection of light on the optic disc, the corresponding part of this field of vision is invisible. So the part of image that falls on this field of vision is not perceived because it has no photoreceptors optic disc is present on the nasal side to the macula lutea. It is in oval shape and measures approximately about 1.5mm in diameter. Blind spot is also an entry point into the eye for the major blood vessels which supply blood to the retina. Blind spot lacks depression. And the eye coats are also absent at the blind spot. Artificial blind spots can also be present, it can be because of anything that blocks light from reaching the photoreceptors or may be because of local adaptation of the retina as just seeing after a very bright light.
Yellow Spot
Also known as macula lutea. It is an oval shaped pigmented are which is present in the center of the retina of the human eye. Yellow spot is a specialized structure for high acuity vision because it contains high density of cones (photoreceptors with high acuity). It is called yellow spot because it absorbs excess blue and ultraviolet light that enters into the eye. So we can say that this region of the retina act as a natural sunblock. The yellow coloration of this region comes from its content of lutein and zeaxanthin, which are yellow colored xanthophyll carotenoids. Macula lutea can only be viewed with light from which red has been filtered. The fovea is present at the center of the macula and have the largest concentration of the cone cells. Thus, the yellow spot is responsible for the central, high resolution, color vision that is possible only in good light. Yellow spot or macula lutea have eye coats. Yellow spot lacks visual receptors but it is sensitive to light.
