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Posted: Fri 8:58, 08 Apr 2011 Post subject: air max 90 Can Pinhole Glasses Improve Air Max 20 | |
It may take weeks or months to get used to pinholes so that the eyes see only one image instead of multiple overlapping images.
Claims that pinhole glasses can permanently improve vision are related to claims for the Bates Method of natural vision improvement. The Bates Method teaches people to see only one small point clearly at a time, to quickly scan across an image instead of staring and seeing the entire image clearly without moving the eye. No Cure, No Harm The effect can be seen by looking through a small hole punched into a piece of paper. A pen or pencil can be used to poke a hole about one to two millimeters across. Even without wearing glasses, an image seen through the hole (held close to the eye, like glasses) will be sharp and clear. They do make images temporarily clearer - not by changing the eye but through optical effects (depth of field) outside the eye. Conventional medical opinion says that when the pinhole glasses are removed, vision returns to how Read on Quality of Life After LASIK Eye Surgery Laser Eye Surgery Risks & Complications of LASIK Bifocals and Sports How Pinhole Glasses Work - Basic Camera Optics In camera terms, pinhole glasses (also called spectacles Air Max 2003, eyeglasses and sunglasses) reduce the effect of the eye's focusing errors by increasing optical depth of field by reducing aperture size. Anyone dissatisfied with prescription glasses can consider using this alternative-medicine device. Pinhole glasses are worn like normal glasses. Instead of transparent glass or plastic for lenses, opaque black plastic "lenses" are used. Wearers see through small holes (pinholes) in the black plastic. Despite these limitations some people may find pinholes more relaxing than conventional glasses. Pinholes could be especially beneficial to people who have trouble adjusting to bifocals. However air max 90, there is only anecdotal evidence for this, no rigorous scientific studies or surveys. In 1993 the US Federal Trade Commission took successful legal action against companies making such claims (the companies settled out of court). Can Pinhole Glasses Permanently Improve Vision? What are Pinhole Glasses? There is no "power" for pinholes. The same pair of pinhole glasses can be used by people with different degrees of vision, different power lenses: positive lenses (convex, for longsighted or farsighted)negative lenses (concave, for shortsighted or nearsighted)combination lenses (bifocals)Comparing Pinhole Glasses with Prescription Lenses Pinholes train people to do this by creating multiple overlapping images ("fly vision") if the wearer tries to see the entire image without moving the eye. A single image is seen only if the wearer looks through one hole at a time, moving the eye to scan the entire image. This will make sense to photographers. Reducing a camera's lens aperture will make more objects in a photograph come into focus. However there are no authoritative medical studies supporting claims that eyesight can be permanently improved by either pinholes or the Bates Method. There are individual claims but this is anecdotal evidence air max tn 8, not science. Vision will not be as clear with pinholes because the black plastic between the pinholes will form a net or web pattern over everything seen. Side-vision can also be blocked (pinholes should therefore not be worn when driving). The main criticism against pinhole glasses is that they have not been proven to cure eyesight problems as claimed by some, not that they are harmful (unless used improperly: in the sun, when driving). |