How to choose progressive lenses
The progressive lens can effectively control the deepening of myopia, but there is no reliable empirical evidence. At present, the height of the lens frame is only about 30mm. The distance from the design of the transition interval is not enough, and the comfort of the eye is difficult to adjust the short distance. From the quality and technology, the foreign brand design process is stable and mature, but the price is too high, there are still a lot of people who are not easy to adapt. The parameters of progressive lenses need to be determined by strict optometry.
The fabric of eyeglasses cloth
Ordinary fabric: They are only applicable to the surface that has been cleaned.Because the ordinary fabric has no space to accommodate dirt, the surface of the cloth will be very dirty, and difficult to wash clean.
Microfiber fabrics: They are used wet to emulsify dirt and oil, and the microfiber is easier to wipe off. It is highly absorbent, making it very quick to clean the spilled liquid.
Fine fiber double velvet fabric: It feels soft, gentle, with the plump texture, but more single velvet.
Suede fabric: The feel and appearance are quite like natural suede, fine and smooth, soft and plump, used to wipe glasses. It will be clean and won't scratch the lens.
Can blue glasses double up as sunglasses?
The main function of sunglasses is to keep out dazzling strong light, to reduce the eye adjustment that causes fatigue or the harm that strong light stimulation causes. Their light transmittance is very low, only suitable for use when the sun is strong outdoors. If wearing sunglasses indoors, or at dusk, or even in the evening, because the light is reduced, it will not play a role in protecting the eyes or even will increase the burden of the eyes. The Anti-blue lens is yellow-green and needs to meet the transmittance and blue obscurity. If you are walking outdoors for a short time, good blue light glasses can of course completely meet your outdoor eye protection needs, but due to the high light transmittance, it is not suitable for a long time outdoors, as the sunglasses. Because although it can block UV rays, they are not very good at the filtering of strong light. General anti-blue glasses can not be equal to sunglasses, the main function is not the same, and the use of the scene is not the same.
Titanium alloys have low thermal elasticity
The thermal conductivity of titanium is about 1/4 of nickel, 1/5 of iron, 1/14 of aluminum, and the thermal conductivity of different titanium alloys is about 50% lower than that of titanium.
The elastic modulus of titanium alloy is about 1/2 that of steel, so its rigidity is poor and is easy to deform, and it is not suitable to make slender rods and thin wall parts. When cutting, the spring back of the processing surface is very large, about 2 ~ 3 times of stainless steel, resulting in severe friction, adhesion, and bonding wear of the knife surface.
Do Blue Light Glasses Work?
When wearing blue light glasses, you may ask whether the blue light glasses really work. In fact, many users have the same troubles. To answer this question, some researchers have made research and have found that blue light glasses make it possible to remain fully engaged in our technologically advanced world, without taking on the negative effects of blue light.
With the blue light blocking glasses, you can focus on the task at hand without negative effects. Besides, with the blue light blocking glasses, you can even sleep well and reduce eye strain. You can also test your blue light glasses are real.
What progressive spectacle lenses are best?
Essilor is a brand, and it designs, manufactures, and markets a wide range of lens products to help people correct and protect their vision. Essilor adheres to the corporate mission of 'improving vision, improving life', invests 200 million euros in research and development every year, and constantly launches new products to enhance consumers' experience in wearing glasses. Continuous innovation has always been the core gene of Essilor. In 1959, Essilor created the resin lens, and in the same year, it invented the world's first progressive lens. Innovation involves technology, manufacturing, sales, and service. Based on innovation, they can make as many people as possible obtain visual health, and this is the driving force to promote their development.
Safety effects of non-prescription glasses
Safety glasses are available in a variety of styles for different users. There were glasses to protect his eyes from shocks or damage, like those used by people who lost an eye in the past. Many of them often wear protective goggles to protect their eyes from injury and to maintain a degree of vision. Safety goggles made of shatter-proof materials have become a staple in many industrial places, from factories to construction sites. Because in such an environment, the likelihood of being hit by debris or mud is very high.