Why is a prescription for glasses different from a prescription for contact lenses?
The frame glasses degrees are the optometric degrees of the eye, and the difference between the frame glasses degrees and the contact lens degrees is mainly due to the different contact distances between the two lenses and the eye. Usually, degrees of contact lenses and glasses need to be converted by a professional through vertex diopter. The conversion formula is Fc=Fs/(1-d×Fs). In the formula, Fc is the diopter of contact lens, Fs is the diopter of glasses frame lens, and D is the distance between frame glasses lens and cornea. Assuming that the prescription of frame glasses is -4.00d and the distance between lens apex is 12mm, the prescription of contact lenses is -4.00/ [1-0.012×(-4.00)] = -3.82d.
How To Use Contact Lens Correctly?
Check your eyes for abnormal cases. Do your eyes sting or dry? If so, it is recommended not to wear contact lenses for the time being. Look in the mirror to see both eyes carefully, if it is red and swollen or if is both eyes full of bloodshot? If you do, you can no longer wear contact lenses, and you can go to a professional store for inspection. After putting on the contact lenses, block the left and right eyes respectively to see if the vision of one eye is clear. If the eye vision has decreased or blurred, check if the lens is dirty. If the lens is still the same, you should go to a professional store to find out the reason.
Can night driving glasses prevent blue light?
Night driving glasses are called night vision goggles. Some night-driving glasses have anti-reflective coatings. Night driving glasses reduce glare by scattering and filtering blue light. Blue light is the shortest wavelength in the spectrum and is possible to cause glare when it enters the eye. The night driving glasses, available in colors from yellow to amber, filter out a lot of glare, and other light, and then make it difficult to see in dark conditions. But tests and studies have shown that night driving glasses don't improve night vision or help drivers see pedestrians faster than they won’t wear them.
Ray-ban Driving Glasses
Ray-Ban sunglasses, an international brand, were created in the 1930s, especially for the US Air Force, to block the fierce light at high altitude, with a very good UV protection function. Through the precise manufacturing and polishing process, Ray-Ban lenses are free of optical deviation and will not cause eye strain, headache or fatigue after wearing.
Types of Adjustable Glasses
Adjustable glasses come in different types including adjustable reading glasses, adjustable focus glasses and adjustable focus reading glasses.
Adjustable reading glasses have an adjustable focal length and compensate for refractive errors. They provide variable focusing so you can adjustable them for desired distance and prescription. They are often used for reading because you do not need to adjust the position of your eyes.
Adjustable focus glasses offer an adjustable focal length. They are used to correct refractive errors including presbyopia. They provide variable focusing so as to adjust the glasses for seeing things close up or far away.
Adjustable focus reading glasses are the same as adjustable reading glasses. You can adjust the dials of the glasses so you do not need to reposition your eyes to see objects clearly in the near or far.
Uvex Stealth OTG Safety Goggles
They provide more protection and coverage than other prescription safety glasses. Due to the full seal around the eye, these OTG safety goggles prevent chemical splashes, and bumps, and scratches, making them wonderful general-purpose safety goggles to wear over your prescription glasses. Dura-Streme's scratch-resistant coating helps keep the lenses crystal clear, which is especially important when wearing the underlying glasses.
How to Choose Glasses for Square Face?
Cat-eye glasses: cat-eye glasses are currently a very popular fashion trend. The upswept browlines provide curves and movement that are suited for any face shape. So, if you have a square face, you can try cat-eye glasses.
Oval glasses: oval glasses can soften your strong angles and balance your face and minimize your strong features. So, if you have a square face, you can try the oval glasses.
How to choose the best glasses for square faces? After reading this post, you may have some ideas. If you want to choose sunglasses for square faces, you can also follow the above suggestions. If you want to choose a new pair of glasses or sunglasses, Koalaeye glasses are recommended, which are stylish and at a cheap price.
