enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Convergence insufficiency - Wikipedia

    en.wikipedia.org/wiki/Convergence_insufficiency

    Convergence insufficiency. Convergence Insufficiency. Other names. Convergence disorder. Specialty. Ophthalmology, optometry. Convergence insufficiency is a sensory and neuromuscular anomaly of the binocular vision system, characterized by a reduced ability of the eyes to turn towards each other, or sustain convergence .

  3. Snellen chart - Wikipedia

    en.wikipedia.org/wiki/Snellen_chart

    In the most familiar acuity test, a Snellen chart is placed at a standard distance: 6 metres. At this distance, the symbols on the line representing "normal" acuity subtend an angle of five minutes of arc, and the thickness of the lines and of the spaces between the lines subtends one minute of arc. This line, designated 6/6 (or 20/20), is the ...

  4. Visual acuity - Wikipedia

    en.wikipedia.org/wiki/Visual_acuity

    Eye examination for visual acuity. Visual acuity is a measure of the spatial resolution of the visual processing system. VA, as it is sometimes referred to by optical professionals, is tested by requiring the person whose vision is being tested to identify so-called optotypes – stylized letters, Landolt rings, pediatric symbols, symbols for the illiterate, standardized Cyrillic letters in ...

  5. Accommodation reflex - Wikipedia

    en.wikipedia.org/wiki/Accommodation_reflex

    The accommodation reflex (or accommodation-convergence reflex) is a reflex action of the eye, in response to focusing on a near object, then looking at a distant object (and vice versa), comprising coordinated changes in vergence, lens shape ( accommodation) and pupil size. It is dependent on cranial nerve II ( afferent limb of reflex ...

  6. Eye chart - Wikipedia

    en.wikipedia.org/wiki/Eye_chart

    Landolt C. Lea test. logMAR chart. An eye chart is a chart used to measure visual acuity comprising lines of optotypes in ranges of sizes. Optotypes are the letters or symbols shown on an eye chart. [ 1] Eye charts are often used by health care professionals, such as optometrists, physicians and nurses, to screen persons for vision impairment.

  7. Eye examination - Wikipedia

    en.wikipedia.org/wiki/Eye_examination

    29271-4. An eye examination, commonly known as an eye test[ 1], is a series of tests performed to assess vision and ability to focus on and discern objects. It also includes other tests and examinations pertaining to the eyes. Eye examinations are primarily performed by an optometrist, ophthalmologist, or an orthoptist .

  8. Refractive error - Wikipedia

    en.wikipedia.org/wiki/Refractive_error

    This means that the refractive power of the eye matches what is needed to focus parallel rays of light onto the retina. A distant object is defined as an object located beyond 6 meters (20 feet) from the eye. When an object is located close to the eye, the rays of light from this object no longer approach the eye parallel to each other.

  9. Accommodative insufficiency - Wikipedia

    en.wikipedia.org/wiki/Accommodative_insufficiency

    Differential diagnosis. Convergence insufficiency. Accommodative insufficiency ( AI) involves the inability of the eye to focus properly on an object. Accommodation is the adjustment of the curvature of the lens to focus on objects near and far. In this condition, amplitude of accommodation of a person is lesser compared to physiological limits ...