Method of wearing the contact lens
Wash your hands before putting on contact lenses, and be careful not to leave long nails, to avoid contamination of the lens by bacteria and nail scratches. Place the contact lens on the tip of your index finger, face-up, and pull your upper and lower eyelids apart with the middle fingers of both hands. Look straight ahead and place the lens gently into the eye (attached to the cornea). Remove the index finger and look down so that the lens is attached to the cornea, and slowly relax the eyelids with the middle fingers of both hands. Blink gently several times (or roll your eyes) to remove bubbles.
What Glasses Lens Thickness Should I Choose?
In this section, we will show you how to choose glasses lens thickness. Lens thickness will depend on the strength of your prescription, your pupillary distance, the size of the frame and the lens material. Usually, high prescription glasses are thick.
If you have moderate nearsightedness, you should choose thinner lenses at the edge thickness of your lenses will be more visible. If your sphere prescription is between -2.50 and -4.00, the lenses with a refractive index of 1.6 would be an ideal choice. A lens with a refractive index of 1.67 is suitable for sphere prescription between -4.00 and -6.00, and any prescription over that a lens with a refractive index of 1.74 will be more suitable.
So, when you purchase prescription glasses, consider the glasses’ lens thickness also. If you want to get a pair of prescription glasses online, Koalaeye Optical is recommended. It is an online optical store and provides all kinds of eyeglasses, sunglasses and frames. Besides, these glasses are stylish and cheap. If you purchased, the glasses will be mailed to you with great convenience.
The advantages of contact lenses
Contact lenses are worn directly over the eye. Contact lenses are tightly attached to the surface of the eye and can always follow the eye, so you can maintain the same open field of vision like a normal person. You can participate in sports and outdoor activities without worrying about your glasses falling off or breaking. You can even use colored contact lenses to change the color of your eyes. Some girls, in particular, can make their eyes look bigger and more beautiful with the help of various color contacts.
How to buy prescription glasses online
Consumers should choose different styles of frames according to their age and professional characteristics. Because everyone has different face shapes, different interpupillary distances, and different diopters, the size of the frames should vary from person to person.
Lenses are divided into glass lens, resin lens, and PC lens, and you can choose according to your preferences. The glass lens has a stable refractive index, good abrasion resistance, and stable optical performance, but it is relatively heavy and easy to break. Resin lens with high light transmittance is light, safe, and not easy to break, but the surface is easy to wear. PC lens has a high refractive index, but the surface is easy to wear.
Standard vs Premium Progressive Lenses: What Are Their Differences
In the above part, we have introduced some basic information about standard and premium progressive lenses. So, what are their differences? In this section, we will show them.
Compared with premium progressive lenses, standard progressive lenses require large frames. Otherwise, you will limit your near vision. On the contrary, if you prefer small and less noticeable frames, premium progressive lenses are the better choice.
Compared with premium progressive lenses, standard progressive lenses are cheaper. For most people, standard lenses are affordable.
Compared with premium progressive lenses, standard progressive lenses are suitable for most people including children.
Premium progressive lenses are customized to your eyes and offer a wider viewing area than standard lenses.
Limitations of NXT lenses
NXT lenses made from Trivex can't be cut by means of traditional edge cutting ways, requiring certain edge grinders, which has caused some problems for retail stores. Therefore, now NXT lenses are more used in some glasses, like sunglasses, protective goggles, and so on.
Difference Between Sunglasses and Optical Frame Glasses
Sunglasses are basically applied to block sunlight and adornment effect. But in the choice of lens material and lens craft respect, it is not very particular. Correspondingly, consumer wears for a fixed number of years, to be in one season or two seasons. Sunglasses are sold with obvious seasonality. Optical glasses are mainly suitable for the use of photometric glasses. Both the lens material and the production process have higher requirements. A panchromatic or half chromatic resin lens is added to an optical lens, and then they can be sunglasses and can try luminosity, made of myopic sunglasses.