What is a qualified plano lens?
First, identify the surface. High-quality products should not have obvious scratches, pitting, edge collapse, sand holes, water ripples, bubbles, and other surface defects. Put glasses next to the place of 33 cm or so at the moment. When looking at the object through glasses, there is no phenomenon that the objects become big or decrescent, and you should not have a feeling that the objects are beating. Otherwise, the quality of the glasses has a problem. Next check through the instrument identification. Finally, check whether the trademark, manufacturer, and quality certificate are true and reliable. The lens of the international famous brand product is often engraved with the manufacturer's trademark, which can be found by careful observation on the edge of the lens.
A clear frame leads the way.
Clear glasses are almost always dominated by large frames. The big frame is an acceptable frame for any face shape. clear rimmed glasses are on the rise, so buy a pair before they hit the streets. Some are full of clean feeling, and the lens frame is slender and elegant. Some models are simple and versatile, suitable for all kinds of fashion styling. Light and fashionable, the collocation of clear frame and aureate glasses frame, is rich high-quality goods feeling.
How Do Pinhole Glasses Work?
Compared to traditional glasses, pinhole glasses work differently. Traditional glasses correct your vision often by collecting rays of light as they enter the eye and forcing them to converge on the retina rather than behind or in front of it.
However, pinhole glasses limit the amount of light entering your eyes so as to enable people to see more clearly.
Different Type of Lenses: How to Choose
In this section, we will list some of the lenses for glasses.
Plastic lenses: In 1947, the Armorlite Lens Company in California introduced the first lightweight plastic lenses. The lenses were made of a plastic polymer called CR-39, because it was the 39th formulation of a thermal-cured plastic developed by PPG Industries in the early 1940s. Plastic lenses are light and low cost.
Polycarbonate lenses: polycarbonate lenses were first introduced in the 1970s and they have become increasingly popular anad remained for a long time. Polycarbonate glasses are slighter and significantly more impact-resistant than CR-39 plastic, making them a preferred material for children’s eyewear, safety glasses, and sports eyewear.
What is the cheapest way to buy prescription glasses?
The choice of frames is not only good-looking but also has a lot to do with whether the polished glasses can be worn correctly. Therefore, special attention should be paid to the selection of spectacle frames, and the pupil distance and the optical center of the spectacle lens should be placed in a suitable position. It should also match the shape of the face so that the paired glasses are not only beautiful but also comfortable to wear. If you don’t choose a frame according to this, but choose anyone according to the general rules, the pupils will not match the optical center of the glasses, and the deflection center of the glasses will appear, causing the prism effect, which is very harmful to the eyes. How do choose a frame? Glasses are worn on the face after all, and they have a decorative effect, so you still have to see if they fit your face shape. In addition, the weight should be light and the frame size should be appropriate. It is best to measure the interpupillary distance, otherwise, it is easy to cause squint and cross-sight. It is safer for children to choose a plate frame with resin lenses. There is a wide range of options for adults. Glass lenses have higher hardness and are not easy to wear, while resin lenses have lower hardness but lightweight, good clarity, and higher protection against ultraviolet rays. Although crystals are expensive, they have high ultraviolet and infrared transmittance.
How to choose a spectacle frame
First of all, we must clarify what are the specific materials of the spectacle frames on the market. At present, the more commonly used glasses frame materials are sheet material, aluminum-magnesium alloy, natural wood, and bamboo materials. Of course, there are other materials such as titanium, TR90, and ULTEM.
Secondly, we have to make it clear that the texture brought by each different material is different, and each has its own advantages. For example, plastic glasses frames are made of sheet materials, which are characterized by easy processing and relatively lightweight. They are generally not easy to deform at room temperature. And the spectacle frame made of metal material is relatively strong, light, and beautiful. Therefore, to learn the advantages and disadvantages of each type of spectacle frame, we can meet our different needs according to each different material.
The frame size has increased.
The larger the frame is, the more obvious it is now, so the edge glare will be more obvious when the lens is polished. It interferes with the visual effect. The frame height of the new glasses must be much larger than the height of the old glasses. Because when you buy big frame glasses, they must find out the pupil height when matching outfits. When you get glasses fitted at the opticians, the opticians don't measure the pupil height. That is, the balance line of the lens should be properly moved up when the lens is processed. If it is not moved up, it cannot be seen clearly.