Astigmatism is a type of refractive error due to rotational asymmetry in the eye's refractive power. This results in distorted or blurred vision at any...

system with astigmatism is one where rays that propagate in two perpendicular planes have different foci. If an optical system with astigmatism is used to...

type of refractive surgery for the correction of myopia, hyperopia, and astigmatism. LASIK surgery is performed by an ophthalmologist who uses a femtosecond...

in substitution of the patient's crystalline, astigmatism is typically not corrected, as astigmatism is mainly attributable to a deformation of the cornea...

particularly in determination of corrective lens power in patients with astigmatism. It is also used for testing near point of the eye. Jackson cross cylinder...

most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short...

all three main optical aberrations – spherical aberration, coma, and astigmatism. This is primarily used to enable wide fields of view, much larger than...

presbyopia who also require a correction for myopia, hyperopia, and/or astigmatism. Benjamin Franklin is generally credited with the invention of bifocals...

implantation. Other common types of refractive errors are near-sightedness, astigmatism, and presbyopia. In young patients, mild hypermetropia may not produce...

treat common vision disorders such as myopia, hyperopia, presbyopia and astigmatism. The first theoretical work on the potential of refractive surgery was...

correct astigmatism. The disadvantages made this type fundamentally flawed for many wearers. The "astig"—named for its ability to manage astigmatism—or "bar-spring"...

common monochromatic aberrations are: Defocus Spherical aberration Coma Astigmatism Field curvature Image distortion Although defocus is technically the...

the drooping eyelid can cause other conditions, such as amblyopia or astigmatism, so it is especially important to treat the disorder in children before...

lens is a lens used to diagnose a type of refractive error known as astigmatism. The Stokes lens also known as variable power cross cylinder lens, in...

optical systems, even those exhibiting optical aberrations, including astigmatism, have at least one stigmatic pair. Stigmatism is applicable only in the...

may result in blurry vision, double vision, nearsightedness, irregular astigmatism, and light sensitivity leading to poor quality-of-life. Usually both...

because it provides high-quality outcomes with less surgically induced astigmatism than ECCE, no suture-related problems, quick rehabilitation, and fewer...

A stigmator is a component of electron microscopes that reduces astigmatism of the beam by imposing a weak electric or magnetic quadrupole field on the...

Cook was declared legally blind in the second grade because of severe astigmatism, but wore contacts and thick "Coke bottle" glasses to correct her vision...

myopia. An astigmatism is a condition in which the curvature of the cornea or lens is abnormal. Astigmatisms can be classified as corneal astigmatism in which...

the rod can be given as : Cylindrical lenses are prescribed to correct astigmatism. Cross cylinder, which is a combination of two cylindrical lenses with...

presbyopia and astigmatism). Introduced in 2005. Monthly Disposable: Acuvue Vita – (senofilcon C) silicone hydrogel material (available for astigmatism). Introduced...

Javal's rule is a mathematical formula used to estimate astigmatism based on keratometry readings. The estimate is useful for high cylinder measures,...

following Airy's development of methods to measure and correct ocular astigmatism. It has only recently[when?] become possible to measure the aberrations...

conducted to determine how much nearsightedness, farsightedness and/or astigmatism an individual may have. Additional specific measurements of the eye will...

of refractive error, along with nearsightedness, farsightedness, and astigmatism. Diagnosis is by an eye examination. Presbyopia can be corrected using...

Hefilcon B 45 10 Optima Toric Alphafilcon A 66 32 SofLens Toric for Astigmatism Omafilcon A 58-60 28–36.7 Proclear 1-Day, Proclear EP, Proclear 1 day...

). For example, the KISA% index (keratometry, I-S, skew percentage, astigmatism) is used to arrive at a diagnosis of keratoconus, to screen the suspect...

primarily in eyeglasses, contact lenses and intraocular lenses to correct astigmatism. A torus is the surface of revolution resulting when a circle with radius...

An oscilloscope, (formerly known as an oscillograph), (informally scope or O-scope) is a type of electronic test instrument that graphically displays varying...