Color process of Contact lenses
Pigment printing process
It refers to the direct printing of pigments or patterns on the inside of the lens and then drying, which is the main production process of poor-quality chromatic contact lenses. Usually, small factories and small workshops use this method. The lens is being phased out because the pigment can easily seep out from the surface during wearing, causing discoloration and staining, and irritation to the eyes, which is a big risk.
Pigment build-in process
To be specific, the lens made by sandwich technology is a three-layer structure, the front and rear are colorless transparent layers, and the middle is a colored layer. After the processing of sandwich technology, the color layer is wrapped in the middle of the front and rear transparent layer, so that the pigment will not contact the eyes, which will not cause irritation and injury to the eyes. The downside of this process, however, is that the lenses are slightly thicker than normal contact lenses and are less oxygen-permeable, so they are not suitable for long-term wear.
The pressed film manufacturing process
This is a relatively new method of a similar sandwich process, and the color (pattern) is also made between the front and rear layers of the lens. But the color (pattern) is used to fill in the film process. During lens curing, the pigment seeps into the material instead of sticking to the surface. It feels as if the lens is covered in color within a single layer. This reduces the middle layer and makes the lens thinner, which naturally makes it more comfortable and permeable to oxygen.
What Are High-Index Lenses?
High index lenses are eyeglasses lenses that are designed to be thinner and lighter than regular lenses. High-index lenses have a high refractive index than their conventional counterparts. So, they are generally recommended for people who have significantly high refractive errors and strong prescriptions for nearsightedness, farsightedness or astigmatism.
High-index lenses correct all types of refractive errors. And they are also available as single vision lenses, or a reading prescription that corrects presbyopia, such as in a bifocal or progressive lens.
High-index lens has a higher refractive index and which is ranging from 1.53 to 1.74. A lens with an index of 1.74 could be up to 50 percent thinner than a regular plastic lens with an index of 1.50.
How to Test Blue Light Glasses (Amber and Red Lenses)
This section will show you how to test blue light glasses with amber or red lenses.
1. The Black and Blue Squares Test
1. Prepare black and blue paper.
2. Wear your blue light glasses after sunset and check whether both paper appear black.
3. If they do not appear black, your blue light glasses can’t block all blue light.
2. RGB Color Chart Test
1. Prepare an RGB color chart as follows.
2. Wear your blue light block glasses and look at the chart.
3. After wearing blue light blocking glasses, if the B section becomes black and the G section becomes darken, it shows that your blue light glasses block blue light and some filter some green light.
4. The less bright the green circle with your blue light glasses, the better they are.
Besides the above ways, you can ask the professional optician to perform a professional blue light glasses test, which would be more reliable. After that, you can know whether your glasses work effectively to block blue light.
What’s more, if you want to purchase a pair of effective blue light blocking glasses, you can try Koalaeye Optical. It is cheap and provides free shipping services.
What are the benefits of keyhole glasses?
These 1950s classic keyhole bridge glasses are suitable for average larger surfaces where wider bridge joints are needed. A wide bridge of the nose will allow the upper margin to run along or below the eyebrow, which will shorten the long face while keeping it close to the face. The design prevents the top of the bridge of the nose from touching the top of the nose, which can be considered uncomfortable and leave marks on contact with the skin. Especially if the frames are dark. The keyhole bridge can be used to adjust the nose shape if necessary.
Anti-fog lens cloth
Anti-fogging glasses cloth is composed of multiple layers of material pressed together, and the material absorbed a sufficient amount of antifogging agent. It can be directly wiped on any lens. Like spray anti-fogging agents, anti-fogging time is relatively short, and can not be wiped or washed. Long time use will affect the life of the lens. The range of lenses available is limited.
What Are Single Vision Lenses?
What are single vision lenses? You may have the same question. Single vision lenses have only one prescription for a given distance. Most reading glasses and distance glasses have single vision lenses because they are designed for people who are difficult in seeing either near or far. Some people are using their single vision glasses for both far and near depending on their types of prescription.
You can choose to wear single vision reading glasses to correct your eyesight if you have trouble reading text on your phone or computer screens. You can also wear single vision glasses to help you make out traffic signs while driving.
Single vision lenses for farsightedness are thicker at the center than those for nearsightedness, which are thicker at the edges. And the single vision lenses generally range between 3-4mm in thickness. The thickness varies depending on the size of the frame and lens material chosen.
After learning some information about one lens glasses, do you know the benefits of them? So, in the following part, we will show you the advantages of single vision lenses.
How to choose blue light blocking glasses?
Nowadays, electronic products such as mobile phones and computers have become indispensable tools in our lives. While these high-tech products bring us convenience and fun, they also bring symptoms such as eye fatigue and myopia. Subsequently, blue light blocking glasses have also received everyone's attention. Anti-blue glasses are only suitable for people who use electronic products for a long time, not for people who are visually fatigued. Exposure to such unnaturally strong blue light for a long time every day, especially for teenagers and children, needs to pay more attention to the prevention of blue light. So, how to choose suitable blue light blocking glasses for kids?
Anti-blue light is necessary, but not all blue light can be filtered out, because blue light will interfere with the body's melatonin secretion after being over-filtered, thereby affecting sleep. Therefore, when choosing blue light blocking glasses, you should choose appropriately according to your own eyes.
For how to choose anti-blue glasses, consumers can distinguish from the color of the lenses. Generally speaking, a lens with a yellow color will have the effect of blocking blue light. But too dark lenses will affect the contrast sensitivity. Therefore, it is recommended that consumers choose moderately. In addition, consumers should also pay attention to whether the glasses products (lenses, frames) have conformity marks, etc. It is best to choose professional and well-known glasses shops to match glasses.
