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.
Evolution of hard coating technology
The first generation of the use of hard coating technology began in the early 1970s, the quartz material is deposited on the surface of a resin lens under vacuum conditions, form a very hard anti-wear film. However, due to the mismatch between the thermal expansion coefficient and the film base material, it is easy to delaminate and crack the film. Instead, it forms the mottle on the surface of the lens, and the effect is not optimal.
The second generation of hard coating technology is the use of the 1980s. The surface of the resin sheet is coated with a material with high hardness and not easy to be brittle and cracked by an immersion process. At this time, anti-reflection coating lenses had appeared and gained the recognition of consumers, but the mismatch between adding hard coating and anti-reflection coating still caused serious lens wear.
The third generation of hard coating technology was developed in the 1990s, mainly in order to solve the problem of wear resistance after coating resin lenses with an anti-reflection film. The hardened material evolved into a polymer organic matrix material.
Fourth-generation coating technology is dominated by silicon atoms, in which the hardened solution contains both organic substrates. It contains inorganic ultrafine particles, including silicon elements, which make the hard coating not only tough but also hard.
Can you look at your phone while wearing polarized sunglasses?
That's because polarized lenses filter the light from some phones, leaving only black stripes visible.Polarized sunglasses have polarized lenses, and cell phone screens have polarized patches in their components. The polarized film has the function of shielding and passing through the incident light, which can make the longitudinal light or transverse light one kind of passing through, one kind of obscured. Because different phones have different polaroid settings, there will be different shades at different viewing angles. Thanks to a combination of polarizing lenses and lenses, both of which filter the direction of light, the screen can't be seen when the shielding and penetrating parts overlap.
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What Are Standard Progressive Lenses?
Standard progressive lenses are a type of progressive lens with plenty of room at the bottom for your near vision. If you need to see something far away and up close, such as a book or magazine, this lens is for you. Transitioning between these viewing areas is often painless for your eyes.
They can reduce glare.
They can absorb blue atmospheric scattering and provides more contrast. When performance is your top priority, the right lens tone can give you the results you want. UV rays are blocked by a special coating on the lenses. And inferior sunglasses not only cannot hold back ultraviolet rays but let lens permeable luminosity drops seriously, making pupil greens. Ultraviolet rays can shoot in large quantities instead, your eye is damaged.
What is blue light?
Blue light is an important part of natural light, and it is visible light with a wavelength of 400nm-500nm in the spectrum. Blue light can be divided into short-wave blue light (harmful blue light) and long-wave blue light (beneficial blue light). Short-wave blue light harms people’s vision and causes specific diseases, while long-wave blue light helps people maintain normal physiological functions, regulate biological rhythms, and treat specific diseases.
Blue light can be seen everywhere in daily life. In addition to blue light in the sun, electronic products such as TVs, computers, mobile phones, ipads, and LED lights also produce blue light in our daily.