![]() ![]() ‘Pinhole glasses do work, in the same way that an old Walkman at high enough volume allows people in the room to hear clear music,’ says Dr Robert Burke, an optometrist at Calgary Vision Centre in Canada. The difference between looking through pinhole and normal glasses has been compared to the contrast between listening to music from a small stereo at high volume and an orchestra playing live. But while these did improve focus, they had the same drawbacks as pinhole glasses and so have been abandoned. Over the years, they have created and tested pinhole contact lenses, pinhole lenses for cataract operations and eye drops that shrink the pupil, creating a natural pinhole. ‘And those who already wear spectacles may need a new prescription if their vision is better when they wear pinhole glasses over their normal glasses.’Įye doctors’ interest in the pinhole effect is not limited to glasses. ‘If a person’s vision is better with pinhole spectacles, they may need conventional glasses,’ he says. Mr Snelgrove, who is campaigning for all motorists to undergo regular eye tests, adds that pinhole glasses can also show someone how good their eyesight could be. Similarly, this month’s article in the journal Ophthalmic & Physiological Optics concludes that pinhole glasses are ‘neither a complete solution nor an over-hyped irrelevance’. He says they are, however, a useful temporary solution if someone has broken or forgotten their usual spectacles. John Snelgrove, an optician in St Albans, Hertfordshire, agrees that pinhole glasses do nothing to improve vision in the long term. Some tell him they have made a lasting improvement to their vision - but when they undergo testing, there has been no change. Mr Hardiman-McCartney adds that every few years there is a spike in interest in pinhole glasses among patients. ‘You can spend a lot of money on spectacles in the UK but you can also buy straightforward glasses for between £15 and £20, so why would you choose pinhole glasses that are inferior?’ If you use them for weeks or months, does your prescription decrease? Do you become less short-sighted? No. ![]() He adds: ‘There is also no evidence that they have any effect on permanently improving your eyesight. Off-set: Cutting the amount of light that enters the eye reduces the quality of the image, so while it may be sharp, it is also dim ‘A lot of people dismiss pinhole glasses outright,’ he says, ‘but that’s not correct because they do focus light - however, that comes with a number of disadvantages.’ And, of course, pinhole glasses look rather peculiar.ĭespite all these drawbacks, they do work for as long as they are being worn, says Daniel Hardiman-McCartney, clinical adviser for the Royal College of Optometrists. Some users complain of headaches, which are probably caused by the strain of focusing in dim light. Cutting the amount of light that enters the eye reduces the quality of the image, so while it may be sharp, it is also dim.ĭepth perception is lost, too, and colours can be murky - and peripheral vision is limited, which means pinhole glasses shouldn’t be worn when driving. The same pinhole glasses will bring into focus objects that are nearby and far away, so they can be used by those who are short-sighted, long-sighted or have presbyopia - and there is no need to switch between different glasses for reading and watching television, for instance. ![]() You can also use them to exercise your ciliary muscles and so, the theory goes, permanently improve your vision it is said that wearing them for just a few minutes a day will produce benefits. The improvement in vision is almost instant. If you just want to see better while you are wearing them, you can wear them for as long as you like. How often you wear pinhole glasses depends on your needs. ![]() Screwing up the eyes has a similar effect. The narrow holes in the lenses filter out the rays of light that would over- or under-shoot the retina, allowing the few that are on target through. Glasses and contact lenses correct vision by collecting the rays of light as they enter the eye and altering their path so they converge on the retina rather than just behind or in front of it. In presbyopia, light from near objects also focuses behind the retina, due to the lens stiffening with age, causing poor close-up vision and difficulty in reading. ![]()
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