Beta titanium
β titanium refers to a particle titanium material that is completed by delayed cooling at the zero bound point state of titanium and does not belong to the alloy. Practical applications will often be processed into alloys to increase their applicability. Although the purity of β titanium is not comparable to pure titanium, its strength, fatigue resistance, and environmental corrosion resistance are better than pure titanium. It has higher strength than pure titanium and other titanium alloys, and the corrosion resistance is stronger and has better elasticity, It is not easy to deform, and is lighter.
Blue light in natural light
Blue light is not the unique light emitted by electronic products, but the visible light that exists in natural light, usually with a wavelength of about 400-500nm. The blue light in the entire waveband can be subdivided into two parts. One part will cause optical damage to the retina of the eye and accelerate the oxidative senescence of cells in the macular area of the retina. Usually, the wavelength of this part of blue light is between 415-450nm, and its damage to the eyes is gradually accumulated and formed. There is also a part of blue light that is beneficial to our human body, that is, blue light with a wavelength of about 480nm. It can adjust biological rhythms and is helpful for sleep, mood, and memory. In addition, experiments have confirmed that daily outdoor activities in the sun can effectively prevent the occurrence of myopia, and short-wavelength blue light may play an important role.
What is vision insurance?
The term vision insurance is commonly used to describe health and wellness plans designed to reduce the cost of regular preventive eye care (eye exams) and prescription glasses (glasses and contact lenses). Some vision plans provide discounts on elective vision correction precesses, like LASIK and PRK. But unlike large health insurance plans, most vision plans are discount or health benefit plans that provide specific benefits and discounts on annual premiums. They can be used to cover most of the cost of eyewear, or they can be used to make high-end eyewear products and improvements, like progressive lenses, anti-reflective coatings, and photochromic lenses, which are much cheaper. Vision insurance plans usually operate differently than other health insurance plans or large medical insurance plans.
Common Problems with Varifocal Glasses
In this section, we will list some common problems with varifocal glasses. The most common problem with varifocal glasses is people being unable to focus on what they need to. Losing focus often leads to some discomforts such as headaches or dizziness when performing tasks that require quick changes in near and middle-distance focus.
Besides, some people also experience a sort of swimming feeling when they are walking. It may be caused by being very aware of the distortions in your peripheral vision as well as the reading portion at the lower part of the lenses.
So, how to use varifocal glasses? The best way is to keep yourself from looking downward as you walk. You may also experience soft focus at the edges of the lenses and need to move your head more to see near objects better.
How to know if lens is polarized?
Make use of LCD screens. Point the glasses horizontally at the LCD screen and then rotate them upward by 45 degrees clockwise. If it is a polarized lens, it will show a change in color deepening. If it does not change no matter how you rotate it, it is not a polarized lens. You can borrow another person's polarized lens or have previously worn a known true polarizer, and place it crossover with the new glasses you want to buy. At this time, you should see the object clearly from the crossover part with your eyes. Then cross the glasses vertically and horizontally, and at this point, the opposite object should not be visible from the intersection. If this condition is satisfied, it means that a true polarized lens is being tested.
Can you buy prescription glasses for night driving?
Your eye doctor may prescribe special night driving glasses with an anti-reflective coating. AR coating helps reduce glare, improves vision, and helps you see better on the road at night. The lenses developed using wavefront diagnostics reduce halos, stellar bursts, glare, and other visual disturbances.
Can clear lenses be polarized?
At present, there are no clear polarized lenses. A polarized lens is a thin film vertically arranged with silicon crystal coating placed inside the lens, just like a shutter, which covers the parallel light and only allows the vertical light to pass through. In this way, the glare from all directions can be eliminated, so it is clear and comfortable to wear. Transparent polyamide, the material of nylon lens, is a new variety of polyamide. The material of the nylon lens is mainly transparent polyamide. Due to the effect of the light filter, only light from a specific direction is allowed to pass through the lens, which filters the dazzling light from the sun on the water, land, or snow very well. It can not only make the landscape soft, clear, and natural but protect the eyes to a certain extent.