Search results
Results from the WOW.Com Content Network
The compound eyes of the arthropods are composed of many simple facets which, depending on anatomical detail, may give either a single pixelated image or multiple images per eye. Each sensor has its own lens and photosensitive cell(s). Some eyes have up to 28,000 such sensors arranged hexagonally, which can give a full 360° field of vision.
The vestibulo-ocular reflex is a reflex eye movement that stabilizes images on the retina during head movement by producing an eye movement in the direction opposite to head movement in response to neural input from the vestibular system of the inner ear, thus maintaining the image in the centre of the visual field. For example, when the head ...
Normal fundus photographs of the left eye (left image) and right eye (right image), seen from front so that left in each image is to the person's right. Each fundus has no sign of disease or pathology. The gaze is into the camera, so in each picture the macula is in the center of the image, and the optic disk is located towards the nose. Both ...
Floaters or muscae volitantes are slowly drifting blobs of varying size, shape, and transparency, which are particularly noticeable when viewing a bright, featureless background (such as the sky) or a point source of diffuse light very close to the eye. They are shadow images of objects floating in liquid between the retina and the gel inside ...
The human eye, showing the iris and pupil. In 1802, philosopher William Paley called it a miracle of "design."In 1859, Charles Darwin himself wrote in his Origin of Species, that the evolution of the eye by natural selection seemed at first glance "absurd in the highest possible degree". [3]
Certain one-celled microorganisms, the warnowiid dinoflagellates have eye-like ocelloids, with analogous structures for the lens and retina of the multi-cellular eye. [59] The armored shell of the chiton Acanthopleura granulata is also covered with hundreds of aragonite crystalline eyes, named ocelli, which can form images. [60]
A stereoscope presents 2D images of the same object from slightly different angles to the left eye and the right eye, allowing the viewer to reconstruct the original object via binocular disparity. When viewed with the proper vergence, an autostereogram does the same, the binocular disparity existing in adjacent parts of the repeating 2D patterns.
A stereoscope is a device by which each eye can be presented with different images, allowing stereopsis to be stimulated with two pictures, one for each eye. This has led to various crazes for stereopsis, usually prompted by new sorts of stereoscopes.