What is blue light?
To prevent blue light, we must first understand what blue light is. The visible light with a wavelength range of 400-500 nanometers is called blue light. The light sources used in daily LED lighting and display products, including mobile phones, flat panels, and TVs, are mostly LED light sources excited by blue light. However, not all blue light is harmful to the human body. The human eye has an extremely low tolerance to blue light radiation in the 400-440 nanometer range. When the light intensity enters this threshold, photochemical damage is likely to occur. However, blue light radiation in the range of 459-490 nanometers is essential for regulating the human body's circadian rhythm and can affect the secretion of human melatonin, which in turn has an impact on the body's biological clock, alertness, and mood.
Scientifically effective anti-blue light lenses must not only block harmful blue light but also cannot filter beneficial blue light. Most of the ineffective anti-blue light products on the market currently have two types of problems. One is that there is almost no protective effect on the blue light in the vulnerable zone of the human eye. The other is excessive protection, shielding the blue light spectrum in the beneficial band so that the blue light that is beneficial for physiological adjustment cannot enter the human eye. At the same time, the color of the lens is yellow, which is prone to color shift, aggravating visual fatigue, and even inducing the risk of myopia.
What are progressive lenses?
Progressive lenses, also called progressive multifocal lenses, are lenses that have multiple focal points. If it is divided from the focal point, the lenses can be divided into single focal lenses, bifocal lenses, and multifocal lenses. The original intention of progressive multifocal lenses is to provide natural, convenient, and comfortable correction methods for presbyopia patients. A pair of glasses can see far away, close up, and mid-range objects. After wearing them, one pair of glasses is equivalent to using multiple glasses. Because of the different nature, characteristics and applicability, progressive lenses are more expensive than single vision lenses.
Why are some glasses expensive and others cheap?
Lenses do not regulate vision, but some progressive lenses can help the ciliary muscles to adjust. The quality of the lens is mainly determined by the transmittance, the surface, the aspherical surface, the refractive index, the coating quality.
The higher the refractive index, the thinner the lens, and the more expensive the price, for some people with high degrees, the lenses also play an aesthetic role. Commonly used are green film, and some are purple film, gold film, etc. How much cheaper is a relative number, and there are many other factors to consider besides price.
The working principle of driving glasses
The driving glasses are designed according to the polarized angle and radian of the lens and the principle of precision optics. It can only let the beneficial light pass through, and other light sources, like strong sunlight, car headlights, and other light sources are filtered, to eliminate the interference of external light, and avoid the appearance of eye-catching, dazzling, and other situations. That's basically how the driver glasses are designed.
5 Signs You Need Reading Glasses
In this section, we will list some signs you need reading glasses.
- You are over 40 years old. Everyone’s eyesight changes at a different rate, but most people develop presbyopia in their 40s. Presbyopia is a condition in which the eye strain to focus on nearby objects, which is different from farsightedness, a condition in which you can see distant objects clearly, but objects nearby may be blurry. Farsightedness is usually present at birth, but presbyopia develops during the aging process.
- If you find that you never seem to have enough light when reading, regardless of the room type or the number of lamps you have turned on, it may be time to get reading glasses. According to a study, a 60-year-old people requires three times as much light as a 20-year old to do the same task.
- If your eyes get tired when reading or working at your computer, you may need reading glasses. Do you find yourself dozing off at your computer, or do your eyelids get heavy when your reading or do detailed work? If so, you may be developing presbyopia, and you may need the reading glasses.
- Another sign you need reading glasses is that you are getting more headaches. Consistently straining your eyes to read or focus on craft could give more headaches. A headache right behind your eyes could be indicative of hyperopia. It is important to remember the 20-20-20 rule: every 20 minutes, look at something at least 20 feet away for 20 seconds. If your headaches persist, you should see an eye doctor and have a check.
- If you see halos, you may need reading glasses. When your lens cannot focus light into your retina, it makes your vision appear blurry. Thus, reading glasses can solve this problem.
Do I need reading glasses? After reading this post, you may have a basic understanding. If you need a pair of reading glasses, try Koalaeye glasses. They are stylish and cheap, and the glasses will be mailed to you with great convenience.
Identify reliable online stores
Online stores division of labor has customer service, processing, packaging, warehousing, after-sales service, operation, art, etc. For processing accuracy, although the equipment is now much higher than before, as long as it is artificial, there will be errors. Even with the highest Essilor automatic grinding machine at present, it is possible to produce errors when the center point and the suction cup are manually operated. After processing is completed, a responsible shop will recheck the number. If the error is large, it must be reconfigured. The formal glasses mall can ensure that the true lens and this is the basic point of a good pair of glasses. Find reputable brands that are proven and believed by most consumers. The online shops should have perfect pre-sale and after-sales service. Professional pre-sale service can give professional guidance.
What Are Colorblind Glasses?
Colorblind means that you can’t see the depth or richness of certain color shades. Colorblind glasses are eyeglasses with specially tinted lenses that help a colorblind person to see colors more accurately. Colorblind glasses do not cure color blindness or produce 100% normal color vision. But they enhance and partially correct certain color vision deficiencies of colorblind individuals.
Color blindness is common among people, especially in men. Blindness is an inherited condition, but can also be acquired. It can also occur if the eyes are damaged due to injury or from another disease that affects vision.
Colorblind glasses claim to assist with detecting differences between colors. They also claim to add additional vibrancy to the colors that people with color blindness may not fully experience.
