Why does shape memory alloy have memory ability?
It starts with its microstructure. When a metal is solid, its atoms are always arranged in a regular way, forming a lattice. Under different conditions, such as temperature, metal may have a different structure, in which case it is said to be in a different phase. The change from one phase to another is called a phase transition. The properties of a metal change during a phase transition. The temperature at which a metal transforms is called the transition temperature. The difference between a shape memory alloy and other metals is that the phase transformation process in a shape memory alloy is reversible under certain conditions.
How to Test Computer Glasses (Clear Glasses)
First, we will show you how to test computer glasses with clear glasses.
1. Ask for Blue Light Glasses Brand Spectrum Report
To find out whether your blue light glasses are the best computer glasses, you should contact the company you bought them from and ask for a spectrum report. It will show you how much blue light your computer glasses can block.
After sending the spectrum report to you, you should make sure that your computer glasses are able to filter at least 30% blue light, otherwise, they are unsafe.
2. Use the Lens Reflection Test
As for how to test computer glasses, you can use the lens reflection test. You can see what color the light is that reflecting off the lenses.
If it reflects the blue light, they are filtering some blue light. If the reflection is violent or purple, the computer glasses may be not effective.
This is a good way for you to perform a blue light test at home.
Advantages of progressive lenses
1. The appearance of the lens is like a single vision lens, and the dividing line of the degree change cannot be seen. Not only is the appearance beautiful, but more importantly, it protects the age privacy of the wearer. There is no need to worry about leaking the age secret due to wearing glasses.(https://www.koalaeye.com/collections/progressive-glasses)
2. Since the change of lens power is gradual, there will be no image jump. It is comfortable to wear and easy to adapt.
3. Because the degree is gradual, the replacement of the adjustment effect is gradually increased according to the shortening of the short distance. There is no adjustment fluctuation, and it is not easy to cause visual fatigue.
4. Clear vision can be obtained at all distances in the visual range. A pair of glasses meet the use of long-distance, near use, and various distances in between. It is especially good for teachers, doctors, music workers, and computer operators because these people not only need to see far and near objects clearly, but most of the time they also need to be able to see objects at intermediate distances such as blackboards, piano scores, and computer screens. This is not possible with lenses other than progressive lenses.
5. At present, both internal and external ophthalmologists agree that young people should wear low-degree convex lenses when reading and writing to reduce near-use adjustment, thereby alleviating or preventing the occurrence and development of myopia. This gives the progressive multifocal lens a new meaning and mission. Physiology found that excessive use of the eyeball adjustment function can form 'accommodative spasm' or pseudo myopia. Continued development can produce longitudinal eye axis elongation and induce 'true myopia' or axial myopia. The external luminosity of the progressive lens can be artificially added to the progressive luminosity. The upper is used for looking far, and the below is used for looking near, which makes the eyeball relax and over-adjust. The ever-changing luminosity of the lens replaces the 'accommodative power' that should have been activated, blocking the vicious circle of adjusting the eye axis elongation, making the eye not easy to fatigue, and slowing the development of myopia.
Heart-shaped face with angular glasses
The heart-shaped face is also a common face shape in daily life. This face shape is somewhat similar to the inverted triangle face shape. Generally, the chin is a relatively sharp face shape. For this type of face, the most important thing is to modify the cheekbones above the nose to highlight the slenderness of the chin. Therefore, it is better to wear a pair of angular glasses, which can effectively modify the facial lines and look more perfect.
Learn the 9 Necessary Parts of Glasses
Rims: the rims lend form and character to your eyeglasses and they also provide function by holding the lenses in place.
End pieces: they are small parts on the frame that extend outward and connect the lenses to the temple.
Bridge: it is the center of the frame that rests on your nose and joins the two rims together.
Hinges: hinges sit between the end pieces and the temple, allowing you to close your glasses folding the temple inward.
Lenses: lenses are the essential parts of eyeglasses. They are clear pieces of glasses, plastic or other lens materials held in place by the rims. The lenses are crafted and shaped with your unique prescription to help you to see clearly.
Screws: they are the small metal fasteners near the hinges and they are used to connect the end pieces with the temples.
Nose pads: nose pads give your glasses a more comfortable and secure fit. They are the round plastic pieces under the bridge that sit on your nose.
Pad arms: pad arms are able to extend from the rims and hold the nose pads in place. They are adjustable to fit the natural shape of your face.
Temples: temples are the long arms on both sides of the frame that fit over your ears for a snug fit.
These are all the 9 essential parts of eyeglasses. Knowing the name of parts of glasses can help you to repair them once they are broken or crooked.
Metal Eyeglasses
Whether you like classic looks or prefer rectangular and functional things, all metals will look new in 2021. Combining the trend of super large frames, you get a big round metal frame. These styles are not heavy and fit all face shapes, from round to square, and anything in between.
Tortoiseshell glasses are comfortable to wear.
For myopic friends, a comfortable frame is needed. Tortoiseshell glasses frame is convenient to wear. When you sweat in summer, the frames will not slide, and the bridge of your nose will not be marked. This is one of the reasons why many people like tortoiseshell frames.
For people who need to wear glasses, it is very important to match a suitable pair of glasses, because glasses will usually use for a long time. If the collocation is not good, it will not only affect the appearance, but bring dizziness, or even eye discomfort. Tortoiseshell glasses frame again gets the public love and becomes the pursuit of personality of modern fashion, tide.