How To Convert Bifocal Prescription To Reading Glasses
In this article, you will learn about the process of converting your bifocal eyeglass prescription to reading glasses. However, you can skip the calculations and contact your eye care professional directly; this does not present any issues. Nevertheless, if you wish to comprehend the entire conversion process clearly, please continue reading below. This is the primary reason why we have promoted this method so widely.
Examination by an optometrist
Your eyeglass prescription form is handwritten or printed out by the eye care specialist at the end of an optometric examination before we select your eyeglasses. You will find all the necessary information about your eyeglass prescription in this document. Of course, if you wish to know what each piece of data represents, please refer to the How to Read Your Prescription article.
Conversion of prescriptions
In the conversion process, the primary prescription data (shown above) are spheres (SPH) and ADD, and you only need to have the ability to add numbers. It’s so easy to convert eyeglass prescriptions to reading glasses. Here is the formula for doing so. You do not even need to know what they mean.
To convert a progressive eyeglass prescription to a reading eyeglass prescription, follow these steps:
Sphere (SPH) + ADD = New Sphere (Reading).
Does it seem straightforward? There are a few points to be noted, of course.
A sign must be added to the addition in the formula above.
Separate calculations are made for the left and right eyes.
The astigmatism (CYL) and axis data should be the same for left and right eyes, if available.
The following examples will help you better understand the process of converting an eyeglass prescription into a sphere (SPH) with a sphere (ADD) of -1.75 and an ADD of 2.25. Based on the formula above, a new Sphere (SPH) is formed by adding the original SPH (-1.75) to the ADD (2.25), resulting in 0.50 (usually the prescription is kept to two decimal places). This data represents the Sphere (SPH) for reading glasses. Astigmatism is present in CYL and the Axis remains the same if there is astigmatism.
A Sphere (SPH) with a diameter of 3.00 and an addition of 1.75, for example, is equal to 4.75 by multiplying the original Sphere (SPH) (3.00) by 1.75. You should keep the same Axis and CYL if you have astigmatism. Isn’t this simple? Your reading glasses are called the Sphere (SPH).
It is also possible to calculate the prescription for reading glasses after the conversion, but two sets of prescriptions are presented here. One is the prescription for glasses prior to the conversion, while the other is the prescription for reading glasses following the conversion.
How does farsightedness differ from shortsightedness?
Neither nearsightedness nor farsightedness are classified as refractive errors. Farsightedness, however, is characterized by the refractive state of parallel light beams being refracted by the relaxed eye and projected behind the retina, and is the result of inadequate refractive powers or insufficient eye axis lengths, respectively.
Seeing distant objects requires moving the focal point behind the retina to the retina using the power of accommodation, since the focal point behind the retina is behind the retina in a farsighted eye. Therefore, a convex lens is usually used to correct this problem. As a result of nearsightedness, the optical focus is in front of the retina, so a concave lens is required to correct it.
As a result, if we observe a nearsighted person through a concave lens (nearsightedness), his eyes are smaller; if we observe him through a farsighted lens (farsightedness), we see that his eyes are magnified. In addition, as the prescription increases, the nearsighted person’s eyes will shrink when they look through the glasses, whereas the farsighted person’s eyes will become larger.
What are the symptoms of farsightedness?
When reading, writing, or doing other close work, farsightedness is prone to producing visual fatigue due to the need to mobilize the eye muscles to adjust both far and near vision. Symptoms may include blurred vision, heavy eyes, pressure, soreness and swelling, deep eye pain, or a headache of different degrees.
There are often varying degrees of changes in the anterior segment and fundus of the eye with moderate to high farsightedness. The most common symptoms include a smaller eye, a shallow anterior chamber, and a smaller pupil. Conjunctival congestion can result from frequent adjustments, leading to chronic conjunctivitis, blepharitis, and blepharitis.
Aside from causing visual fatigue, farsightedness can also cause systemic symptoms, particularly neurological issues.
There are several complications that may occur with farsightedness, such as strabismus and amblyopia. A child with severe farsightedness may suffer diplopia as a result of hyperfocus due to hyperopia at an early age.