Mild Refractive Error Eye
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Refractive Errors Of The Human EyeDrugs Clinic Information What Is a Refractive Error? Refractive error means that the shape of your eye does not bend light correctly, resulting in a blurred image. The main types of refractive https://nei.nih.gov/health/errors/errors errors are myopia (nearsightedness), hyperopia (farsightedness), presbyopia (loss of near vision with age), and astigmatism. Symptoms Blurred vision Difficulty reading or seeing up close Crossing of the eyes in children (esotropia) Causes Overuse of the eyes does not cause or worsen refractive error. The causes of the main types of refractive error are described below: Myopia(close objects are clear, and distant objects are blurry) Also http://kellogg.umich.edu/patientcare/conditions/refractive.errors.html known as nearsightedness, myopia is usually inherited and often discovered in childhood. Myopia often progresses throughout the teenage years when the body is growing rapidly. Watch a video explaining myopia. Hyperopia (close objects are more blurry than distant objects) Also known as farsightedness, hyperopia can also be inherited. Children often have hyperopia, which may lessen in adulthood. In mild hyperopia, distance vision is clear while near vision is blurry. In more advanced hyperopia, vision can be blurred at all distances. Watch a video explaining hyperopia. Presbyopia (aging of the lens in the eye) After age 40, the lens of the eye becomes more rigid and does not flex as easily. As a result, the eye loses its focusing ability and it becomes more difficult to read at close range. This normal aging process of the lens can also be combined with myopia, hyperopia or astigmatism. Watch a video explaining presbyopia. Astigmatism Astigmatism usually occurs when the front surface of the eye, the cornea, has an asymmetric curvature. Normally the cornea is smooth and equally curved in all directions, and light entering the cornea is focused equally on all planes, or in all directions
often are the main reason a person seeks the services of an optometrist or ophthalmologist. But what does it really mean when we're told that our vision is blurry because we have a refractive error? We see http://www.allaboutvision.com/eye-exam/refraction.htm the world around us because of the way our eyes bend (refract) light. Refractive errors are optical imperfections that prevent the eye from properly focusing light, causing blurred vision. The primary refractive errors are nearsightedness, farsightedness and astigmatism. Refractive errors usually can be "corrected" with eyeglasses or contact lenses, or they can be permanently treated with LASIK and other vision correction surgery (also called refractive surgery). FIND A DOCTOR: Do you have a refractive error? refractive error Find an eye doctor near you to have your eyes checked. > How Light Travels Through the Eye In order to see, we must have light. While we don't fully understand all the different properties of light, we do have an idea of how light travels. Watch this video on what causes blurry vision and how we can correct it. A light ray can be deflected, reflected, bent or absorbed, depending on the different substances it mild refractive error encounters. When light travels through water or a lens, for example, its path is bent or refracted. Certain eye structures have refractive properties similar to water or lenses and can bend light rays into a precise point of focus essential for sharp vision. Most refraction in the eye occurs when light rays travel through the curved, clear front surface of the eye (cornea). The eye's natural (crystalline) lens also bends light rays. Even the eye's tear film and internal fluids (aqueous humor and vitreous) have refractive abilities. Recommended For You Say goodbye to discomfort with ULTRA contact lenses Learn how Optometry Giving Sight helps 670 million people to see again Questions about cataracts? Find all the answers in My Cataract Journey Save 10-30% off your eye exam using the BenefitsPal™ card How the Eye Sees The process of vision begins when light rays that reflect off objects and travel through the eye's optical system are refracted and focused into a point of sharp focus. For good vision, this focus point must be on the retina. The retina is the tissue that lines the inside of the back of the eye, where light-sensitive cells (photoreceptors) capture images in much the same way that film in a camera does when exposed to light. These images then are transmitted through the eye's optic nerve to the brain for i