字幕列表 影片播放 列印英文字幕 Hello and welcome to the TranslatorsCafe.com Channel! In this video I am going to explain how to determine the optical power of your new eyeglasses without visiting a doctor. Do you know that you can determine the optical power (diopters) of your next pair of prescription bifocal or progressive eyeglasses by yourself? How? — By using inexpensive glasses from a drugstore and several trial lenses. Why do you want to do it yourself? Because an ophthalmologist to whom you pay your hard-earned $100 or £100 for a visit has only about 10 to 15 minutes to help you and that's simply not enough time. By the way, I do it not only for yourself (I am a presbyope), but also for my wife, who has myopia. She's been wearing glasses for about 30 years and all this time she was could not distinguish between birds. Only after I tested the lenses for her and ordered her a new pair of glasses, she began to recognize the birds from large distances not only by their voice, but by their appearance. Before that, like many short-sighted people, she simply believed that it wasn't possible to improve her vision to 20/20. Now, wearing the correct pair of glasses she can see again like a ten-year-old kid and during our daily 10-kilometer walks she constantly shows me all kinds of hawks, woodpeckers, cardinals, blue jays, finches, and other large and small birds. Interested? Watch this video, and you will learn how you can help yourself to improve your vision! I made this video for people like me, who are in their forties, fifties of sixties. As most people after their mid-forties, I started experiencing presbyopia at about age 45. I had to hold books and magazines farther and farther away from my eyes to be able to read them. I had to move away from the computer monitor. At the same time, I could see things that were far away just fine. If you are younger, you can continue watching just to be prepared for the future. These problems will appear anyway and you cannot avoid them, like you cannot avoid gray hair or wrinkles. I did not start wearing glasses until I realized that I couln't work without mistakes anymore. I worked as an English-Russian translator and started wearing glasses at work only after I made a scandalous mistake on the first page of my translation and the client who understood English well enough noticed it and kicked up a big fuss. I tried several over-the-counter glasses, found most suitable for my work and then went to the ophthalmologist to get a better pair of glasses. I remember how hard it was for me to persuade her to prescribe me glasses that I needed. I needed +2 to view at the monitor and paper original simultaneously and she wanted to prescribe me +1, which I knew and checked was not suitable for my daily work in front of the monitor. Now I know for sure that if you are well prepared, if you did your homework, then most probably you will know about your problem more than your doctor does. I am not talking about prescription or give medical advice here — I am not a doctor. In this video I will talk only about eyeglasses with spherical lenses. We will not discuss astigmatism here simply because I don't have it and don't have experience correcting it. Remember that if you are past sixty, regular eye exams are the only way to catch diseases like glaucoma that develops slowly over time without any pain. Though the name presbyopia looks like a disease and it is even called a disorder in various classifications, it is not a disease. It is a natural part of ageing. Presbyopia is the gradual decline of eyes' ability to focus on close objects causing those objects to appear out of focus due to hardening of the crystalline lens of the eye because of its aging. The ability to focus on nearby objects declines throughout person's life. Small children can accommodate to 20 or even more diopters (that is from +20 to 0 diopters or from 5 cm to infinity). A young adult can have the amplitude of accommodation of only 10 diopters (from +10 to 0 or from 10 cm to infinity). Senior persons at age 60 and over have the ability to view clearly only from one or two meters to infinity or only 1 or even 0.5 diopter. If you are past age 60 and you want to feel that your vision is still like that of a 10-year old kid, you will need different pairs of eyeglasses depending on whether you are sitting in front of a computer monitor, driving down a highway, replacing a battery in your watch or reading a book on a tablet, or do all the above in different lighting conditions. It is impossible to use a single pair of eyeglasses for every activity. Example of activities at your home or workplace. Working in front of the computer monitor and paper document reading. When you are working in front of a monitor, you have to remain focused on the screen and often change focus to look at your keyboard, you smartphone or paper documents printed in small type. And in the window to reduce eye strain. Properly selected computer glasses should provide the best possible focus of the image on the screen, which is usually positioned 50 to 64 cm (20 to 26 inches) from user's eyes as well as of other things surrounding the user (books, documents, your keyboard or smartphone), on which the user usually look at much less distances (usually 25 cm or 10 inches). For persons past age 45 the best choice is either bifocals (less expensive) or progressive (more expensive) with diopter values selected for distances stated above. I will later explain how you can select yourself the best possible optical power of your new glasses. If only close objects are blurry and far objects appear normal, then you need simple reading glasses for this kind of activity. If, however, far objects are also blurry, then for this kind of activity you will need bifocals or progressives to view very distant objects (at infinity) as well as your smartphone or other objects at about 20 cm (8 inches) from your eyes. Polarized magnetic clip-on filters are preferred for glasses used for this kind of activity — it is more convenient and much less expensive than photochromic lenses, which are optical lenses that very slowly darken when exposed to UV radiation. Good vision acuity and wide visual field are crucial for safe driving, therefore don't rely on someone else — check your vision yourself and order appropriate glasses. Remember that photochromic (transition) lenses will not work in your car because they are activated by UV exposure and your windshield and closed side windows actually block almost 100% UV rays. Progressive lenses have reduced visual field and therefore bifocals are much better for safe driving. Progressives are unsafe for driving because of reduced clear vision field. For driving, especially for night driving, you need anti-reflective coating on your eyeglasses. What kind of frames do you need for driving eyeglasses? When choosing the frame style for driving, select a frame with thin rims (eye wires) and thin temples that will not block your peripheral vision. That's all. You can select big name frames for several hundred or even thousand dollars if you like paying for pure air (which, as everyone knows, is free) or no-name frames for one dollar — it simply does not matter. All of them are equally good. What matters is only the thickness of their rims and temples. You will need bifocals with upper lenses for infinity and lower lenses for viewing your GPS receiver and dashboard instruments. Polarized magnetic clip filters are not suitable for using conventional GPS receivers because any navigation device contains its own polarizer and if two polarizing filters are combined, the visibility can be reduced to zero. What you will need for checking; I will remind one more time that here we are talking only about glasses with spherical lenses. Your old eyeglasses with known optical power of both lenses or if this is your first pair of eyeglasses, you will need a cheap pair or two pairs from a drugstore or dollar store. Measuring tape. Several trial lenses: Because your vision is changing, you will need these trial lenses for a long period to be able to check your vision and order your new eyeglasses. You can buy trial lenses on eBay — they sell spare trial lenses for opticians' test kits at approximately 6 dollars per piece. Another, cheaper option, is buying two pairs of one-dollar reading glasses +0.5 and +1.0 and only two negative trial lenses on eBay. You can also order simple prescription glasses with one lens –1 and another –0.5 in an online optical store. Determine the type of activity for which you want to order your new glasses. For example “glasses for driving with a GPS receiver” or “computer glasses”. Using a measuring tape, measure the distance from the bridge of your nose (or your eyes) to the objects you work with. For a driving glasses example, the first distance will be infinity; to determine the second distance, while sitting behind the wheel, measure the distance between the bridge of your nose and the GPS receiver screen. For computer glasses, sit comfortably in front of your monitor and measure the distance between the bridge of your nose and the screen. Then measure the distance between the bridge of your nose and a document you want to read while working on a computer. Now you have the two necessary measurements. One for the upper lens (distant viewing) and another for the lower lens (near field). If this is the first time you are going to order your glasses, it would be better to visit an ophthalmologist who may determine that you have astigmatism. However, don't trust his or her prescription. Most probably it is incorrect: your doctor has spent only 15 minutes on you! Don't order your glasses at this time! Go to the drugstore/dollar store instead and purchase one or two pairs of cheap eyeglasses depending on the type of eyeglasses in your prescription. Check if you can view objects at the working distance. For example, if this pair of glasses is for driving, check if distant objects are in focus while wearing the glasses for distance and if the smartphone screen at the same distance as in the car is sharp while wearing glasses for near field. If not, use correction lenses and correct the doctor's prescription as described below. Test your distant viewing first. For driving eyeglasses, it is better to test in the evening looking at distant signs. For example, I test my vision from the balcony while viewing the names of stores across the plaza. If you found the optical power under poor lighting conditions, the glasses will definitely work when the sun is shining because your pupil, which works like a camera aperture, is contracted in good lighting and hence the sharp focus of the image in the retina can be obtained from various distances. When the pupil in your eye is dilated, a sharp focus can be achieved only for light rays coming from a certain distance. Exactly like in a photo camera. Now test the sharpness of the documents (near vision). Place trial lenses (–1.0, –0.5, +0.5, +1.0) near eyeglasses lenses and determine if you can view sharper with one of the trial lens on the required distance. Do this check for both eyes. Write down the results. Note that if relatively thin lenses are placed together, their powers approximately add. For example, if you determined that with your reading eyeglasses +2 you need an additional +0.5 lens, that means you need a +2.5 lens. Now you have two or maybe four measurements if you eyes are different and you are ready to order your new eyeglasses. Of course, don't forget to measure your pupillary distance — you can do it yourself! Where to buy eyeglasses. Even two different pair of glasses, let alone three or four, can be very expensive at a brick-and-mortar optical store. To save a lot, you can purchase inexpensive pair of prescription glasses online. Examples of good online stores are zenni.com or goggles4u.com. A pair of bifocals will cost about $40 to 60 there. Don't forget about all possible coatings — you will need them all: anti-scratching, anti-glare, and oleophobic. In conclusion, I would like to tell you that my experience shows that if you used to do everything yourself, you can do anything you want and often better than the professionals do. Of course, you will have to spend your time to study theory and to prepare everything. However, if everything described above seems too complicated, then you will not be able to help yourself and you will have to rely on prescriptions given to you by ophthalmologists, which will most probably be … incorrect. If you think I am wrong, please share your experience in your comments. I hope you enjoyed this video and found the idea interesting. If yes, don't forget to hit the like button. If you have not subscribed yet, please also consider subscribing because every subscriber is a bonus for the TranslatorsCafe.com channel. Thanks if you do subscribe! Thanks for watching. See you next time.
B1 中級 美國腔 DIY驗光師 自行選擇新眼鏡 (DIY Optometrist Choose Your New Eye Glasses by Yourself) 14 0 wei 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字