What is cellulose acetate?
Cellulose acetate refers to a thermoplastic resin obtained by esterification with acetic acid as a solvent and acetic anhydride as an acetylating agent under the action o...
Round face
Style selection: Suitable for the choice of square or rectangular sunglasses, through the angular shape to increase the three-dimensional sense of the face and the sense of line. Avoid r...
Feel with the eye
Clarity: After wearing glasses, under the normal eye distance, such as looking at an eye chart at 5 meters or a book or computer screen at 30-40 centimeters, you should be able to...
In the discussion “Can nearsighted people not wear glasses?” On this topic, we first need to clarify the definition of myopia, the causes and the role of glasses in correcting vision, a...
Optometric data
Accurate degree: Go to a professional eye institution or optician for optometry to obtain accurate myopia, farsightedness, astigmatism degree and axial position data. This is the ba...
Silver halide photochromic change technology: the photosensitizer silver halide (or other photosensitizers such as silver barium, copper halide and chromium halide, etc.) is added to the resin lens...