Design principle of progressive multifocal lens
For the same piece of the lens, the top is used to see far, the bottom is used to see close. The upper and lower degrees are different.
There is not a sudden change in the distance degree fixed above the lens to the near degree fixed below the lens, but a gradual transition between the two through gradual changes in refractive power, which has special benefits over common bifocals or trifocal lenses.
Contact Lens Materials - HEME Mixed Materials
Using HEMA as the matrix, other monomer components are added to improve the hydrophilicity, oxygen permeability, anti-precipitation, and other functions of the lens.
What Do the Numbers on Glasses Mean?
In this section, we will show you the glasses numbers meaning. These numbers on glasses frames are the measurements that indicate and describe the size of your eyeglasses frames, specifically:
- The eye size number (it is the size of the lenses on your frame).
- The bridge size number (the distance between the lenses).
- The temple length number (it is the size of that part of your eyeglasses frame, which rests upon your ears).
The three numbers mentioned above are the key measurements that describe the glasses measurements of the frames in eyeglasses. For example, you will see three numbers like 51-17-145 at the temple of your glasses. These numbers help the optician to choose the best-fitted frame for your head size and facial features.
All of these three numbers are measured in millimeters. These variations in frame numbers are fitted by a skilled optician so that it should be best fitted, be comfortable and look good on the appearance.
The purpose of glasses donation activities.
Regular social donation activities should be carried out in a planned way. For the poor in the rural areas of the disaster area and the poor in the urban districts, donations of materials or funds can not only feel the warmth and humanistic care of society in life and material, quickly resuming production and rebuilding homes. It gives them a sense of psychological security and stability, which is more practical than physical help.
Who are suitable for progressive lenses?
A progressive piece is suitable for most old people to wear. The proper person is the one who has the visual needs of the long, medium and short distance cares about beauty, and is willing to accept new things. In order to avoid binocular vertical prism differences, for the wearer whose equivalent spherical lens with anisometropia is more than 2D, especially if the difference in refractive power of the vertical meridian is more than 2D, it should be checked with caution. Opticians whose vision needs do not match the progressive lens design, like dentists, often experience blurred vision when working with the far side of the lens to look closer.
Best Frames For Heart-Shaped Faces
The heart-shaped face should be one of the favorite faces of Asians. It is characterized by a wide forehead, prominent cheekbones, and narrow and pointed lower jaw. This face shape is not balanced up and down in appearance, and the upper part is larger and more prominent than the lower part. Need to wear sunglasses with a wider bottom, which can increase the width of the lower half of the face. The lower mirror foot position also helps to improve this effect. Don't pick a special big style, normal size will do. Pilot sunglasses with a more angular top and bottom can be used to balance the roundness of the heart-shaped face and chin, increase the sense of facial lines, and visually make the face fuller. Retro black round sunglasses, coupled with a handsome choker, highlight the full street casual style. The recently popular 'inverted triangle sunglasses' are also very suitable for heart-shaped faces. The raised angle of the frame can correct the facial lines and add some angularity to the face. The inverted triangle sunglasses also have a retro temperament, and it feels that there is a mysterious demeanor hidden.
Does the titanium frame cost a lot?
It can be decided according to the titanium frame technology, design, and specific material. Titanium-nickel shape memory alloy, titanium alloy, β titanium alloy frame belong to the high-end consumer goods, and the price is generally more than 300. In recent years, with the improvement of people's living standards in China, the domestic demand for titanium frames is expanding rapidly, and there are many manufacturers of titanium frames in China, but all the raw materials are still imported from Japan. Up to now, there are very few manufacturers that develop and produce titanium glasses frames by themselves in China. The production of β titanium alloy wire used in the frame is in the stage of development in China.