How to test a blue-light lens?
Blue-light-blocking lenses are now focused on refractive indices of 1.56 and 1.60. If you buy lenses that are not of either refractive index, be wary. Of course, with the development of technology, now some brands have produced 1.71 refractive indexes blue-light-blocking lenses, suitable for people with high myopia to wear. The true lens package should at least have the product name, refractive index, dispersion coefficient, transmittance, color, SPH, CYL, and other indicators. These indicators are perfect, can be treated as the reference basis of the formal product. In addition, you can go to a professional optical shop or testing institutions for testing.
What Is Progressive Lens?
Progressive lenses, also called multifocal lenses, have three prescriptions in one pair of glasses. So, it allows you to see near, middle distance, and far objects without changing your glasses. The progressive lenses are designed for people who are over 40 years old who are both nearsighted and farsighted. The progressive lenses come with the following features:
- There is no distinct line between all visions(near, intermediate, and far).
- Most popular lens for anyone with presbyopia who wears
- Expanded intermediate zone for better computer vision.
From the above information, you may have known the differences between bifocal lenses and progressive lenses. As for progressive vs bifocal lenses, which one is better? It is difficult to judge because each of them has unique features. So, if you do not know choose which, you can listen to the eye doctor.
What are pure titanium rimless glasses?
Pure titanium rimless glasses combine the advantages of pure titanium glasses with rimless glasses. Rimless frames are mainly focused on lightweight, reducing the pressure on the wearer and enhancing comfort. Moreover, rimless frames are not obvious either in appearance or in weight, which alleviates some of the distress caused by myopia. Pure titanium material increases this lightness to the extreme. Pure titanium frame has a uniform and natural color. It is not easy to fade, not easy to rust, and anti-allergy. It is the pursuit of high-end taste glasses lovers' first choice.
Why are eyeglass frames are so expensive?
Designers pay a lot of time cost and brainpower cost, as well as knowledge and creativity. Sunglasses from luxury brands often combine their iconic elements with high quality. They are delicate, durable, and recognizable. The comfort and durability of wearing, as well as the fine workmanship of the sunglasses themselves, reveal the texture and taste invisibly.
Can the TR90 frame be changed?
TR90 material was originally made in Italy. It is difficult to color the frame, and usually, the color is painted on the outside. It can float in saltwater. It is suggested that the lens should be a water first to prevent overheating of the lens. Then, at the end of the nose, hinge, or the temple, carefully fold it in until it is comfortable to wear. You can use a household hair dryer to blow heat first, which can play the role of softening. Note that the hairdryer should be moved when heating, and do not aim at only one place. TR-90 is the most popular ultra-light material in the world at present.
What kind of lens is a progressive lens?
Progressive lenses are optical lenses designed for simultaneous correction of far, medium (for computer use), and near (for reading). They are Progressive Additional Lenses (PAL). The so-called progressive, The so-called progressive, is the use of polishing technology to achieve a gradual transition between the two focal lengths. The advantage of this design is that the wearer can see far and near objects alternately without taking off the glasses.
Disadvantages of Progressive Lens
There are deformation areas under the left and right sides of the lens, which make the image blurry and irregular. It takes 1-3 weeks to get used to it. In addition, it has a narrower field of view in the near and middle distances, and long-term concentration on the narrow focal point can easily make the eyes tired. Suitable for people who need to alternate between distant, medium, and near vision.
However, with the development of science and technology, more and more progressive multifocal glasses have emerged that have a wider field of view, more comfortable wearing, and better meet the needs of eyes. Nowadays, the use rate of progressive lenses among middle-aged and elderly people abroad is quite high. Single-lens and double-lens reading glasses are gradually being replaced by progressive multifocal glasses.