How to protect your contact lenses?
When wearing contact lenses, do not drop any eye drops, and only use a special moistening solution for contact lenses. In daily life, we recommend that dry eyes can be relieved with lubricating fluid, but we do not advocate frequent use of lubricating fluid, so as not to make the eyes become dependent on lubricating fluid. The right way is to do blink training. The ingredients contained in the eye drops will remain in the lenses, which will cause certain damage to the eyes and pollute the lenses. Some eye drops can make the lenses tinted after use, which will affect the transmittance and a refractive number of the lenses and make the vision blurred. Ladies who need to make up should wear contact lenses before making up. When removing makeup, remove contact lenses before removing makeup, to avoid the makeup sticking to the lens and damaging the lens and eyes. Lenses should not be lent to others to avoid cross-infection of eye diseases. You can't wear contact lenses while swimming or bathing.
If you need reading glasses when using a computer, you may want to choose a lower reading glasses power. This is because most people view their screen from a greater distance from their eyes than when they are reading a book or a magazine.
However, if you need reading glasses for looking at something very close or very small, you may need a pair of stronger power glasses.
In most cases, when two reading glasses’ powers seem equally suitable, choose the glasses with the lower power. Picking reading glasses that are too string typically will cause more discomfort problems than reading glasses that are a little too weak.
How to choose a spectacle frame
First of all, we must clarify what are the specific materials of the spectacle frames on the market. At present, the more commonly used glasses frame materials are sheet material, aluminum-magnesium alloy, natural wood, and bamboo materials. Of course, there are other materials such as titanium, TR90, and ULTEM.
Secondly, we have to make it clear that the texture brought by each different material is different, and each has its own advantages. For example, plastic glasses frames are made of sheet materials, which are characterized by easy processing and relatively lightweight. They are generally not easy to deform at room temperature. And the spectacle frame made of metal material is relatively strong, light, and beautiful. Therefore, to learn the advantages and disadvantages of each type of spectacle frame, we can meet our different needs according to each different material.
Keyhole glasses are different from saddle glasses.
Glasses without nasal pads are common, usually with plastic eyewear frames and metal frames. Plastic frames without nose pads usually have a saddle-shaped nose area, therefore this type of bridge is called a saddle bridge. The keyhole is designed to touch the two points of the bridge of the nose, eliminating pressure from the top of the nose. This style is a bold fashion statement for both men and women. The design has short pads on either side of the nose, which is thought to be the most comfortable area.
Disadvantages of bifocal glasses
The disadvantage of bifocal glasses is that the different areas are clearly spaced and the appearance is not beautiful. The medium distance is fuzzy, and the adaptation period is needed, there is a prismatic jumping phenomenon. The focal distance between the upper and lower lenses is different, with a clear dividing line. The main disadvantage is that when the line of sight moves from far to near, there will be interference like jumping, and the middle distance object image is blurred. Students can adapt to sitting still in a class by wearing bifocal glasses, but they can only wear glasses when they are in class or studying because of the inconvenience and even danger caused by the interruption of the glasses.
Why are designer brands in Japan popular?
Japan has long admired the spirit of design and craftsmanship. These designer eyewear brands are often hosted by single designers with strong personal styles. Different styles of glasses design language are highly consistent. Some of these designers have transitioned from fashion design to graphic design, others have been designing glasses all their lives, or even just picked up inspiration in the creative process and started a brand. There are many such designer brands, and the better brands often have very loyal and stable customer groups.
Parameters of lens material selection
Since the refractive index of the lens material varies for the light of different wavelengths, and white light is made up of various colors of light of different wavelengths, the dispersion phenomenon occurs when the lens refracts white light. The dispersion coefficient is an important index to identify the sharpness of lens imaging, which is usually indicated by Abbe number (Abbe number = dispersion coefficient). The larger the Abbe number, the smaller the dispersion, and vice versa, the smaller the Abbe number, the larger the dispersion, and the worse the resolution of the image.
Humans have been using glass lenses for about 300 years, and it was not until 1947 that the first resin lenses made of CR39 were produced. A big reason for using resin lenses is their safety, i.e. impact resistance. Only lenses that pass the Drop Ball Test are considered safe. Combining the above two parameters, we can compare different lenses.