Varifocal glasses are corrective lenses used in glasses to correct a condition called presbyopia. Presbyopia is a condition associated with aging, in which the eye has a diminished capacity to focus on near objects. A varifocal lens is characterized by its property of gradually increasing lens power. The gradient starts at the wearers distance prescription, at the top of the lens, and reaches maximum addition power, or full reading power at the bottom of the lens. The length of the progressive power gradient depends on the design of the lens. The range of final addition power is from 0.75 to 3.5 diopters. The addition value that is prescribed depends on the level of presbyopia of the patient. Generally, older the patient, higher is the addition.
If you are looking to buy varifocal glasses online, there are a number of online retail stores which have progressive lenses on sale. Although they might require a week’s notice to prepare and design your lenses according to the consumer prescription, it would be well worth getting it done online, as they sell their glasses at market prices due to competitive market pricing. Also, you will have a number of options to choose from. All information regarding the sale of Varifocal glasses are listed on the stores websites.
Some of the advantages and uses of Varifocal glasses are listed below:
1.) The additional lens power required for clear vision at different distances is accounted for by the natural position of the eye during majority of the day, and can be further adjusted by positioning the head in such a way that the eye sees through the appropriate part of the lens.
2.) It requires only minor head adjustments, as these lenses are used for near vision tasks like reading which are lower in the vision field as compared to looking at distant objects which are higher in the vision field.
3.) Progressive addition lenses avoid the discontinuities or image jumps in the visual field and are more cosmetically attractive.
4.) Now let us look at some disadvantages of Varifocal glasses:
5.) Some distortions might arise while using these glasses, as well as blurring. For most people, these aberrations are highly disturbing, and the degree of discomfort may be so high that it makes them switch to traditional bifocals.
6.) You have to be precise in the positioning of your glasses. You have to position them close to your face and as high up as possible. If the lens is not placed properly, there may be greater difficulties in the visual field, depending on lens design. Your field of vision may become narrower, you may see only from one eye, or there might be blurring.
Users of varifocal lenses need some time to get used to their glasses. The time of adjustment may be a few days to a couple of weeks. This adjustment period may be characterized by frequent headaches as a result of wearing the glasses. Some people may not adjust to the glasses at all when they buy varifocal glasses online.