Almost 80 percent of the population in the world has seeing problems. So you can say eyeglasses are an inseparable part of people’s life. Those with eye problems can not think of a day without their eyeglasses. But when the first eyeglass was invented is not clear. It is believed that in the 13th century the Venetian glass blowers used reading stones which were made from solid glass and were placed in a handheld single frame made from wood or bone. These were like magnifying glasses.
The actual eyeglass concept was most probably introduced in the 12th century in Pisa, Italy by Salvino D’Armate. He used two small glasses in one frame which, worked like magnifying glasses, and they used it to read. These could be mounted on the bridge of the nose. All these glasses helped read or look at close objects. In the early 1400 glasses for looking far were introduced. In the 16th century, the first eyeglass frame like the modern one was invented, by the Spanish craftsmen. In the 17th century, people understood properly the concept of nearsightedness and farsightedness. And they also got a clear idea of how concave and convex lenses work.
There are mainly two problems in seeing that may happen to your eyes. One is you can not see things in the far, and the other is you have problems seeing things closer to you. The first one is called myopia, and the later is called hypermetropia or presbyopia. In myopia, the image you want to see is projected in front of your retina and the reason behind is that the focal length of your eye lens has decreased.
In hypermetropia or presbyopia, the image of the object is projected behind your retina. For hypermetropia, this happens as the focal length of your eye lens increases and for presbyopia, your eyeball gets hard and loses its capability to focus properly. Myopia is treated by using a concave progressive lens and hypermetropia or presbyopia is treated by a convex lens. For people above 40, both problems can occur.
In that case, a contact lens that helps to look far and near is used and called a bifocal lens. Our focus in this article will be convex lenses or reading glasses. This article will be helpful for you to know how to choose reading glasses.
Types of lenses:
- Concave: This type of lenses is preferable for people who can not see in the far as the image of the object is projected in front of the retina due to a decrease in focal length of the eye lens. The concave lens helps to project the image on the retina thus solving the myopia problem.
- Convex: These lenses are best for people who can not see objects near them or can not read properly as the image of the object they are trying to look at is projected behind the retina. This happens when the focal length of the eye increases. The convex lens projects the image on the retina thus solving the problem.
- Bifocal: These types of lenses have two parts. The upper part works as a concave lens, and the lower part works as a convex lens.
- Trifocal: These types of lenses have three parts. Two parts are for seeing far away and reading or looking at very close range. The third or upper part helps to see things at an intermediate distance or in your arms reach.
- Anti-reflective: This coating helps your eyes to avoid glares and reflections.
- UV protective: This coating is specially designed to save your eyes from eye strain because of ultraviolet rays from the sunlight.
- Scratch-resistant: This type of coating helps your lenses from getting scratched easily.
- Blue light coating: Due to the frequent use of mobile devices and computers our eyes may feel hurt or fatigued. This happens due to harmful blue lights from these devices. These blue lights directly pass through the retina by harming it. The blue light coating helps to block this harmful light from harming your eyes.
- Photochrome: Some people may find it difficult to work in direct sunlight. Photochromic coating or photochromic lenses are helpful for them. This coating changes the color of the glass too dark to avoid direct sunlight.
- Tinted coating: Tint can help to see better. Yellow-type tint increases contrast, gray does not change the color of objects, and light tint may be helpful to hide the wrinkles around your eyes.
- Mirror coating: Mirror coating is for fashion only. This coating is available in many colors. This coating hides your eyes.
Type of frames:
- Full rimmed: This type of frame encloses the lenses and is quite rugged. Full rimmed frames can be found in both plastic and metal.
- Rimless: These frames have only the arms, bridge, and hinges. They are very lightweight.
- Semi-rimless: These frames only cover the upper portion of the lenses. Lightle heavier than rimless glasses.
- Low bridge: These frames are suitable for those who have a low nose bridge.
- Wire frames: These lightweight frames are only for circular face shape lenses.
How to choose the perfect reading glass?
If you are suffering from vision problems, then first you have to consult with an eye doctor. Tell him what problem you are facing and how severe it is. He will check your eyes and give prescription glasses or prescription reading glasses or prescription lens or prescription eyeglasses for your eyes. In most cases in presbyopia doctors prefer reading glasses.
If your eye problem is not severe, then you can go for over-the-counter glasses. First, you should take a diopter strength eye exam. A Diopter chart is a chart in which there are rows of words according to the power of the eyes. You can decide the lens power by understanding at which row you can see clearly. After getting the power from the test you can decide what type of lens you want. Plastic lenses are more durable than glass lenses. If you suffer from sunlight, then choose photochromic lenses.
If you work frequently on a laptop or computer and use mobile phones a lot then obviously you should go for blue light lenses. After choosing the type of glass you can choose what type of frame you like, or best suits you. In case you can not get a diopter test over the counter reading glasses have magnification marked on them. You can try several then choose the one through which you can see better.
The eyes are very important parts of your body. Negligence of eye problems can cause permanent damage to your eyes. Whenever you are feeling uneasy or having trouble with your vision consult with a good eye doctor first and follow whatever he prescribes. You should check your eyes to a doctor at least once a year. Hopefully, by going through this article, you will be able to understand how to choose reading glasses.