How do fishing goggles work?
When fishing in calm water, the light is straight to us. Because of the wind and waves on the water, there will be countless reflective surfaces, just like we face countless mirrors, leading to not clear float. For a long time, eyes will be very tired. Fishing sunglasses block the uncomfortably bright light and protect the eyes from UV damage. All of these functions are achieved by metal powder filters that 'select' light as it comes in.
Roger Bacon
One of the first people credited with inventing glasses was an English friar in the 13th century, Roger Bacon. In his Opus Majus (c. 1266), he outlined the scientific principles of the use of corrective lenses. Some writers believed that monks or friars possessed secret knowledge about glasses, which they later disseminated around the world. Most famously, William Molyneux wrote in his Dioptrica Nova (1692). Unfortunately, there is no evidence that Bacon ever applied his theoretical knowledge of perspective (optics).
The frames should be firm.
What kind of glasses are not easy to damage? It should be said that there are only two types of such frames: full metal frames full non-metal frames. However, be careful when choosing these two frames. Younger children prefer to move, and self-control is poor, so choosing a full non-metal glasses frame is appropriate. Although the middle school children are active, the self-control will be relatively strong, so you can consider the choice of a full metal glasses frame.
Polycarbonate vs Plastic Lenses: Which One Is Better?
From the above information, you may have learned some features of polycarbonate glasses and plastic lenses. So, do you know which one is better?
Here are some a few differences between both lenses to determine which one is better.
- Polycarbonate lenses are more expensive than plastic glasses.
- Polycarbonate lenses are very resistant to tint compared with plastic lenses which accept tints.
- Polycarbonate glasses have inherent UV protection, while plastic lenses do not have.
- Polycarbonate glasses have higher impact resistance and offer greater protection than plastic lenses.
- Polycarbonate glasses are lighter than plastic glasses.
- Plastic glasses have a higher optical clarity than polycarbonate lenses.
So, from the above part, you may have learned which one is better and you may have a decision of how to choose.
The Disadvantages of Aspheric Lenses
Here, we will show some disadvantages of aspheric lenses.
The aspheric lens has a relatively small light area. When the eyeball rotates around, it will blur a little when looking at the outside through lens edge. In other words, the visual range of the line of sight becomes smaller.
Human’s eyeball is spherical and the eyeball rotates to the edge. Through aspheric lenses, the objects near the eye appear protruding.
Many optometrists have problems adjusting their frames almost daily. In the eyes of the customer, it is simple to use tools, but in reality, the technology involved is pretty important. It is no exaggeration to say that a good pair of glasses and optometry, collocation is equally important. If the customer's optometry parameters are normal, and glasses collocation is accurate, but wearing is not comfortable. So the collocation of glasses is very key, and many problems can be solved by the collocation of glasses.
How Long Does It Take to Get Used to Varifocals?
When you get a new pair of glasses, you have to get used to them. So, how long does it take to get used to the glasses? Some people only need a couple of days to get used to them while some others may need up to two weeks.
It is normal if you can only see the frame rim of your glasses when you first wear them. The reason for this lies in the brain’s visual center. It needs to adapt the new and greatly improved visual conditions.
