Corrective lenses, also known as prescription lenses, are optical devices that are used to correct refractive errors in the eyes. Refractive errors occur when the shape of the eye prevents light from focusing directly on the retina, resulting in blurred vision. The most common refractive errors include myopia (nearsightedness), hyperopia (farsightedness), astigmatism, and presbyopia.
Myopia is a condition in which distant objects appear blurry, while near objects can be seen clearly. This occurs when the eyeball is too long or the cornea is too steep, causing light to focus in front of the retina instead of directly on it. Hyperopia, on the other hand, causes nearobjects to look blurry, while distant objects may still be clear. This happens when the eyeball is too short, or the cornea is too flat, causing light to focus behind the retina.
Astigmatism occurs when the cornea or lens is irregularly shaped, causing blurred vision at all distances. It can cause distorted or elongated images, as the light does not focus properly on the retina. Presbyopia is an age-related condition in which the lens of the eye gradually loses its flexibility, making it difficult to focus on close objects. This typically occurs around the age of 40 and affects most people.
Corrective lenses work bending the light rays that enter the eye, redirecting them to compensate for the specific refractive error. There are three main types of corrective lenses:
glasses, contact lenses, and refractive surgery.
Glasses are the most common and widely used form of corrective lenses. They consist of lenses that are mounted in a frame, which is then worn on the face. The lenses can be specifically tailored to an individual’s prescription, providing the necessary correction for their refractive error. Glasses can correct a wide range of vision problems, from mild to severe prescriptions.
Contact lenses, as the name suggests, are lenses that are directly placed on the surface of the eye. They provide an alternative to glasses and are especially popular among those who want a more natural appearance or need vision correction for specific activities, such as sports. Contact lenses work floatin