What Are Progressive Lenses?
Your eyes change with your age. When your reach your 40s, you may find that it is difficult for you to focus between a book, a website on a computer screen and the conference room whiteboard. Progressive lenses are growing in popularity among people who need help seeing near, far and in-between.
Progressive lenses have grown in popularity and are one of the most common solutions to treat vision loss that occurs with age or presbyopia. Progressive lenses have a seamless increase in magnification from the top to the bottom of the lens, helping you see clearly at all distances with just one pair of glasses. The top portion of the lens enables you to see the far-away objects, the middle portion of the lens enables you to focus on the intermediate objects and the bottom to see objects close-up. The prescription changes little by little across the lens surface providing a gentle transition.
After knowing what the progressive lenses are, do you know what are the pros and cons of progressive lenses? If not, keep on your reading and we will show you some information.
Drivers can wear night-vision goggles
Night-vision goggles can prevent headlights from blinding, add color saturation, and make the field of vision clearer. The normal night vision glasses are golden yellow in color and have a metal coating on the surface. This is the use of diamond high perspective reflection film technology, in the lens to add color and film layer, in order to maximize the brightness of the object being seen. It is to compensate for the light for driving, which makes light pass through your eye. It can increase the three-dimensional sense of objects, making the line of sight more clear, to avoid confusion caused by blinding headlights.
What Glasses Lens Thickness Should I Choose?
In this section, we will show you how to choose glasses lens thickness. Lens thickness will depend on the strength of your prescription, your pupillary distance, the size of the frame and the lens material. Usually, high prescription glasses are thick.
If you have moderate nearsightedness, you should choose thinner lenses at the edge thickness of your lenses will be more visible. If your sphere prescription is between -2.50 and -4.00, the lenses with a refractive index of 1.6 would be an ideal choice. A lens with a refractive index of 1.67 is suitable for sphere prescription between -4.00 and -6.00, and any prescription over that a lens with a refractive index of 1.74 will be more suitable.
So, when you purchase prescription glasses, consider the glasses’ lens thickness also. If you want to get a pair of prescription glasses online, Koalaeye Optical is recommended. It is an online optical store and provides all kinds of eyeglasses, sunglasses and frames. Besides, these glasses are stylish and cheap. If you purchased, the glasses will be mailed to you with great convenience.
Contact Lens Materials - Non-HEMA materials
The non-HEMA materials are hydrophilic soft lens material, which does not contain HEMA components. They are stronger and more oxygen permeable than most HEMA polymers.
The water content of regular hydrogel lenses varies from 30% to 58%. When oxygen passes through the hydrogel, it needs to be carried by water molecules in the material. Therefore, the higher the water content of the lens, the higher the oxygen permeability value. The softer the lens, the more comfortable it is to wear, which is conducive to the metabolism of the cornea. However, at the same time, the higher the water content of the lens, the faster the water evaporation, easy to dehydration, and easy to cause dry eyes. A lens with high water content has low material density, poor durability, and easy breakage, so they are suitable for making lenses that are frequently changed or discarded. On the contrary, the lens with low water content has good formability, easy operation, durability, and is not easy to dehydrate and cause dry eyes.
Why My New Glasses Give Me a Headache?
The new glasses make me dizzy or headaches. You may have these symptoms when getting a new pair of glasses. Why do the new glasses give me a headache? When getting used to the new glasses, your eyes and brain have to work harder to see clearly through your new lenses. The more your strain to see, the more likely you are to get a headache.
So, how long to adjust the new glasses? It may take a few days. If you still feel uncomfortable after wearing the new glasses for a few weeks, you should ask for the eye doctor or the optician to check whether your glasses are made correctly and check whether your prescription is correct.
In addition, if you want to get a new pair of glasses, you can try Koalaeye Optil, which is an online optical store and helps you to prescribe your eyeglasses with great convenience. Koalaeye Optical provides various glasses, including progressive glasses, blue light blocking glasses, sunglasses, driving glasses, and different shape frames.
Metal frames have many benefits.
It has a certain hardness, good softness, good elasticity, wear resistance, corrosion resistance, gloss, and good color and luster.?For example, for the high nickel alloy frame, nickel content reaches more than 80%. It mainly has nickel-chromium alloy, manganese nickel alloy. High nickel alloy’s corrosion resistance is better. In addition, the material elasticity is good.?Titanium frame has a high melting point, light material, strong corrosion resistance, and solid electroplating. The eyeglass frame that uses pure titanium is deft and comfortable, more in accord with human body engineering. And flexibility is good, long-term use is not out of shape. And they do not fade, do not cause skin allergy, relatively durable.? Memory titanium alloy frame refers to a new alloy made up of nickel and titanium according to the atomic ratio of 1:1.?Memory titanium is more resistant to corrosion than high nickel alloys but less resistant than pure titanium and β-titanium.
How To Choose Better Night Driving Glasses?
Driving at night has a high accident rate because of poor visibility, blinding headlights, and fatigue. Now the market exists a few main glasses: sunglasses polarizing lenses, Glasses that use or mimic the first generation of patented technology. So how do you compare the options between driving and wearing glasses?
Night driving lens is relatively special compared with daily driving lens, not only to prevent strong light and see the road more clearly. According to the national motor vehicle driver special glasses standards, QBT 2659-2004 daily light transmittance should be more than 8%, night light transmittance should be more than 75%. Be sure to consult customer service. Ask about the situation. Note that a pair of polarized sunglasses are not suitable for use at night, and the light transmittance must reach the national safety standards.
