Need to re-adapt to new glasses
When the glasses were damaged, the glasses were not replaced in time. As a result, the nearsighted person wears old glasses and continues to look at things. The old glasses have 'remodeled' the eyes in the long-term process, and the eyes have adapted to the old glasses. Therefore, even if the power of the new glasses is the same as that of the old glasses, the new lenses will feel brighter. In this case, eyes produce uncomfortable symptoms. It is recommended to use the new glasses early the next morning. After a night's rest, the eyes will be easier to adapt to the new glasses. After a few days of continuous wearing, the dizziness symptoms will disappear.
What kind of glasses are bifocals?
Bifocals are mainly used in presbyopia correction, providing presbyopic opticians with a clear vision for both near and far use in one pair of glasses. The bifocal lens can be divided into two separate areas, with the upper part of the lens providing clear distance vision and the lower part providing clear near vision. The two regions of the bifocal lens provide different refractive forces, and the difference between these two refractive forces is the reading proximal addition, which compensates for adjustment during presbyopic reading.
Why are titanium glasses so expensive?
Strong and Durable. They are widely used in aerospace technology, jewelry, surgical instruments, and other fields. It is the most progressive material in the eyewear industry. Titanium is a very hard, lightweight metal that is proper for eyeglass frames. With good hardness, high strength, the glasses are not easy to deform. It is not easy to scratch and wear and has good corrosion resistance and plasticity. It has a high melting point, corrosion resistance, and hard electroplating. Titanium can be made into memory metal, which means it can bend and return to its original shape. Hinge is not easy to break, having rust resistance, impact resistance. When it's used in glasses, it fits the bill.If you've ever broken a frame, titanium is possible the best material for you.
Bifocal lenses have two observation areas separated by visible lines, a larger observation distance area, and a smaller reading area. It may take some time for people who are wearing bifocal glasses for the first time to get used to the lenses. This is mainly due to learning how to move the eyes between the observation distance area and the reading area. Some people will also find that there will be an 'image jump' phenomenon at the visible line between the distance and the reading area, especially for those with limited mobility, who must look down when walking. The best way to get used to bifocals is to wear them as much as possible.
TR90 spectacle frame
TR90 is a composite super-elastic resin material first invented by Koreans and used in the manufacture of glasses. Its characteristics are lightweight, excellent flexibility, and slightly lighter than pure titanium. After this material is being made into a finished product, it is non-adjustable. The application is basically injection molding. Koreans are the first to apply to glasses production, which has been popular for a few years, and then popular in the Japanese market. Now it is basically mass-produced in China. The high-end high-quality TR90 spectacle frames are produced in Shenzhen, and the low-end low-quality ones are in Wenzhou because they are much cheaper.
The design evolution of progressive lenses
Spherical and aspheric designs
The design of the front surface of the far-use area of the early progressive lens is similar to that of the ordinary spherical single vision lenses, so it is called a spherical progressive lens. Since 1974, the front surface of the far-use region of the lens is designed to be aspheric by designers, which not only reduces the peripheral aberration but makes the lens thinner, lighter, and less powerful.
Hard and soft design
For hard design, the channel is short, and the gradient is large. The near-use area position is high. The effective visual area of remote and near-use areas was larger. Peripheral astigmatism is relatively concentrated. Because surrounding astigmatism increases rapidly and the distribution is dense, the curve effect is more obvious. The gradient area is narrow. It is more difficult and takes longer for wearers to adapt.
Lenses with soft designs have slower gradients, longer gradients, and wider gradients. The angle of rotation of the eye from the far area to the near area is greater. It's easier to get used to. Compared with the hard design, the effective visual area of the far and near use areas is smaller, and the location of the near use area is lower.
Single, diverse, and individualized design
Initially, the progressive lenses used a single design, in which each basic curve was scaled equally and a luminosity combination was added within the range of its semi-finished lens blanks. The steepest base curve uses the same lens design as the flattest base curve. Lenses designers quickly realized that the overall performance of the lens could be improved by microcustomizing the lens design, leading to progressive lenses with multiple designs. This kind of design is called diverse design. By the mid-1990s, there was the emergence of individualized lens designs. In addition to using different gradients, these first individualized lens designs used steeper baseline curves with a slightly larger approach area to compensate for increased magnification and reduced field of view.
Symmetrical and asymmetric design
There is no difference between the left and right eyes in the symmetrical design of progressive lenses. As the eyes turn inward when they see near objects, the gradual gradient area gradually tilts to the nasal side from top to bottom, so the left/right progressive lenses should be rotated clockwise/counterclockwise respectively during processing. An asymptotic lens with left and right eye divisions is called an asymmetric design. The gradient is gradually and moderately inclined to the nasal side from top to bottom. The refractive force, astigmatism, and vertical prism of the two sides of the left and right gradient of the asymmetric design lenses are basically similar. At the same time, considering the characteristics of eye movement parameters in binocular vision, the peripheral aberrations of the corresponding positions of the left and right lenses were appropriately balanced to improve the visual effect of the wearer.
h3>Types of Colorblind Glasses
Colorblind glasses come in different tints based on the type and severity of color blindness you have. If you have some eye conditions such as short sightedness or long sightedness, you may need a pair of prescription colorblind glasses. If you do not have other vision problems, you may just need a pair of non-prescription colorblind glasses. And the non-prescription colorblind glasses are cheap than the prescription ones.