Bifocal glasses have the lenses with two powers meant for near vision and distance vision. The upper segment of the bifocal glass has power which corrects distance vision. The lower segment of the glass corrects near vision. When we read something, for instance, we look down and see through the lower segment of the glasses. When we look into distance, the line of sight passes through the upper segment. How are bifocal glasses different from [...]
The term ‘reading glasses’ is used for glasses which are used for near work including reading. The power of the lenses in the reading glasses may exclusively be only for near work or the glasses may have lenses for both distance and near work (bifocal or progressive reading glasses). Why do we need reading glasses? In children and young adults, the natural lens in the eye is more elastic and has the ability to change [...]
There are many known factors which promote worsening of myopia (short sightedness or near sightedness). Here is a list of those factors. Find out which ones are relevant to you or your affected relative and try to make changes so that you eliminate them and prevent worsening of short sightedness. It’s important to realize however that all factors are not modifiable. Constant wearing of glasses can cause worsening of myopia. Children with low myopia should [...]
Presbyopia is a condition of middle-age in which near vision becomes poor. It is usually corrected with glasses. The newer treatments are aimed at getting rid of glasses. Corneal inlays are tiny implants which are inserted into the cornea changing its shape and refractive power. Raindrop inlay is one such example. A gel-like device that looks like a miniature contact lens, the Raindrop inlay is smaller than the eye of a needle, and is placed [...]
We need reading glasses to correct presbyopia. Presbyopia is a condition which appears around the age of forty years in which distance vision is good but objects at close distance are blurred. This condition is related to age and is clinically similar to hypermetropia (far-sightedness) which is found in younger age group. Click here to know more about presbyopia. Symptoms of Presbyopia Around the age of 40 years, you may start noticing that you cannot [...]
All of us have different distances between the two eyes. The distance between the centers of pupils of both eyes is called as pupillary distance (PD) or inter-pupillary distance (IPD). This distance is important when you want to use glasses for sight. The power of the lens in the glasses is not equally distributed. It is usually more in the center and lesser in the periphery of the lens. Therefore, the alignment of the center of [...]
First, let me explain what intermediate vision means. Based on the distance between the object we see and our eyes, we use terms such as ‘distance vision’ and ‘near vision’. An example of distance vision is watching the television and example of near vision is reading something (printed material/phone) in your hand at a distance of about 12-18 inches. Intermediate vision is something between near and distance vision. For example, the distance between your eyes [...]