Search results
Results from the WOW.Com Content Network
Find the area between a circle and its involute over an angle of 2 π to −2 π excluding any overlap. In Cartesian coordinates, the equation of the involute is transcendental; doing a line integral there is hardly feasible. A more felicitous approach is to use polar coordinates (z,θ).
The pars plana (also known as orbicularis ciliaris [1]) (Latin: flat portion) is part of the ciliary body in the uvea (or vascular tunic, the middle layer of the three layers that comprise the eye). It is about 4 mm long, located near the junction of the iris and sclera , and is scalloped in appearance.
The optic cup is the white, cup-like area in the center of the optic disc. [1] The ratio of the size of the optic cup to the optic disc (cup-to-disc ratio, or C/D) is one measure used in the diagnosis of glaucoma. Different C/Ds can be measured horizontally or vertically in the same patient. C/Ds vary widely in healthy individuals.
For a shooter, eye relief is also a safety consideration. If the eye relief of a telescopic sight is too short, leaving the eye close to the sight, the firearm's recoil can force the optic's eyepiece to hit and cut into the skin around the shooter's eye, leaving a curved scarring laceration on the medial end of the supraorbital ridge and the ...
The young human eye can change focus from distance (infinity) to as near as 6.5 cm from the eye. [32] [33] This dramatic change in focal power of the eye of approximately 15 dioptres (the reciprocal of focal length in metres) occurs as a consequence of a reduction in zonular tension induced by ciliary muscle contraction.
The first two sort of floaters may collect over the fovea (the center of vision), and therefore be more visible, when a person is lying on his or her back looking upwards. Blue field entoptic phenomenon has the appearance of tiny bright dots moving rapidly along squiggly lines in the visual field.
The 2017 video game Perception places the player in the role of a blind woman who must use echolocation to navigate the environment. [35] In the 2012 film Imagine, the main character teaches echolocation to students at a clinic for the visually impaired. This unconventional method spurs a controversy but helps students explore the world. [36]
The globe of the eye, or bulbus oculi, is the frontmost sensory organ of the human ocular system, going from the cornea at the front, to the anterior part of the optic nerve at the back. More simply, the eyeball itself, as well as the ganglion cells in the retina that eventually transmit visual signals through the optic nerve. [1]