Difficulty focusing?!

Difficulty focusing?

sometimes when i wear my glasses i have difficulty focusing from one scene to the next, like on the road when im driving, into a store
i think its b/c of the lighting in differnet places? and that my eyes are fairly weak

I will copy and paste what I read from a website -

http://www.iblindness.org/intro/problemg...

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The Problem with Glasses

When our vision becomes blurry, we normally go to the local eye doctor in order to see what can be done. If the problem is a refractive error (a wrong focusing of the eye, including myopia, astigmatism, hyperopia, and presbyopia), we'll be fitted for glasses (or contact lenses; they work on the same principle) which do compensatory focusing and we're told to wear them all of the time in order to prevent our sight from getting worse. When we complain that things, while clear, look funny through the glasses, or our eyes feel funny, we are told, "Don't worry, you'll get used to it." The natural resistance to corrective lenses is so common that it has had to become standard routine for the patient to be told to spend a couple of weeks (not minutes, but weeks!) getting used to them. Some people never entirely get used to them, even after repeated measurements and fittings.

Compensation of Focus

Refractive errors are not the fixed conditions they are made out to be. They are often transitory conditions. Nobody with perfect sight has perfect sight all of the time, and even the most chronic case of poor sight from refractive error is not fixed at a particular level of refractive error all of the time. Glasses compensate for the error in such a way as to consider it a completely fixed condition that never occasionally gives way to relief. When they are worn, the particular level of refractive error must be continually produced in order for us to see clearly through them. Changes in vision which may have been commonplace before wearing glasses will likely decrease in frequency. Any relief of strain is no longer a relief, because then the focusing with the glasses is wrong and blur is produced. Relaxation is thereby discouraged, and the idea that seeing requires an effort (which produces the correct amount of strain) will be encouraged. With glasses, a clear image only exists with strain.

Glasses are no substitute for normal seeing because they can't correct any of the other problems associated with imperfect sight. They don't address the strain that's present, and since strain affects vision in a larger way than just taking the eyes out of focus, sight with glasses can never be as good as it can be without. Seeing is an arduous task with glasses, instead of an effortless part of perception.

Accommodation-Convergence Relationship

When the eye adjusts focus for the near point, it's called accommodation. At the same time, the eyes turn in a certain amount towards each other so as to point at the same object. The relationship between these two movements gets thrown off with glasses; because of the compensation of focus, the amount of accommodation is greater or less than what the eyes are used to with a certain amount of convergence. When glasses are worn regularly, the eyes get used to the off-balance relationship and may have a harder time focusing without glasses, or the person may even develop convergence disorders.

Discouragement of Eye Movement

By nature, glasses are placed over the eyes such that only the center of the lens is at a right angle to the eye's line of sight. When the eye turns at all, it's looking through the lens at an angle, resulting in some distortion and loss of clarity, so the person is subtly encouraged to fix his gaze through the center of the lenses instead of freely moving his eyes in all directions. This immobility leads to tension and loss of the constant movements that are a key component in the function of perfect vision.

Chronic Bodily Tension

Chronic tension, which causes all sorts of problems in the human body, tends to occur in patterns, not in a single muscle in isolation. With glasses on, a person has hold the neck and body unnaturally stiff in order to provide enough stability to keep the glasses from flying off. There is already enough chronic tension around the eyes from the unnatural effect of glasses, and the extra bodily tension just helps solidify the whole pattern of tension.

Loss of Far Peripheral Vision

It's no secret that a person wearing glasses has little or no awareness of what's going on to either side of him. Glasses only cover a small portion of the visual field, encouraging a person to mentally block out the far peripheral vision. Over time, this can lead to a fixed habit of disregarding peripheral vision, and corresponding patterns of thought. Glasses over time may even be responsible for damage to the peripheral processing capabilities of the visual system; people improving vision often hit a point where they obtain a greater sense of their peripheral vision, as if it had been atrophied or lying dormant.

Loss of Full Depth Perception

The stronger glasses are, the more they flatten the depth of the image, ie: the eyes don't have to adjust focus between near and far, as everything is simulated to be at the same distance, as if everything is being watched on a TV screen. Depth perception is therefore impaired as long as the glasses are on, and the person has to rely on certain visual cues such as relative size and occlusion (blocking) of far objects by nearer objects. Over time, as the style of perception gets ingrained, the person naturally has an impaired perception of depth without glasses as well. Relative size of objects (one cue to depth perception) is confused, as objects will appear bigger or smaller than normal with glasses. Astigmatism correction can also throw off the sense of perspective (the property of parallel lines converging to infinity) when glasses are taken off. People improving their vision often at some point report a greater sense of "3D vision", suggesting that their depth perception was not only suspended somewhat by glasses but also impaired to the point of affecting their quality of depth perception and sense of a three-dimensional world without glasses.

Light Filtering

All glasses block light to some extent, no matter what material they are made from. This is a minor and more theoretical point compared to the rest, but through glasses the world appears duller and possibly less interesting because of it, and it's only natural that this could lead to a glasses wearer having a duller outlook on life. People who learn to see clearly again without their glasses frequently report that colors seem so much brighter than they ever did through glasses, and that the world seems so much more interesting.

The Burning Ant Effect

"Minus" glasses, used for myopia correction, bend light to compensate in such a way that results in the area on which light rays hit the retina being smaller than normal, which is interpreted by the visual system as a smaller image. "Plus" glasses, for hyperopia (farsightedness), work on the reverse principle, resulting in a magnified image. Minus lenses can even be dangerous when looking at or towards the sun - think of a kid burning an ant with a magnifying glass by concentrating the sun's rays, which is what minus lenses do to the retina whenever you look in the direction of the sun with them on. Add to that the fact that people with myopia have a habit of moving their eyes less, and it's an even more dangerous situation. People not wearing glasses rarely suffer any damage from looking at the sun, because of the combined effect of moving their eyes by minute amounts more and not wearing lenses that shrink the point of focus.

Annoyances

Glasses have to be cleaned often from getting dirty, clouded, or wet, and contacts can become extremely uncomfortable if the smallest piece of dust makes it in or the contact lens begins to dry. Glasses fall off, slide down the nose, and contacts can easily fall out or become dislodged. They can obviously both be problematic in any physical activity. Reflections of light off the lenses can be annoying to glasses wearers, not to mention dangerous in certain situations.

Contact Lenses

Contact lenses are free from a few of the above issues, but they introduce the additional factor of a foreign object in the eye. With all the slick marketing and societal acceptance of contacts, it's easy to assume that sticking those things in your eyes is safe. But it isn't - infections, corneal ulcers, and corneal abrasions are not uncommon, and these risks are compounded if you don't take care of the lenses properly or don't remove them at night. This is to say nothing of the dry eyes and other irritations that are more common.

But the important issue is what contacts actually do to a person's process of seeing. First, anyone who has blurry vision without contacts already has chronic tension keeping the refractive error (error of focusing) in place. It can be extremely difficult for anyone to learn to relax or "let go" of this tension and learn to see without it, which is why the exercises in the Bates method are so varied and subtle. When you've got contacts in, the subconscious drive to keep the tension in is increased because it doesn't feel safe to completely surrender when you've got foreign objects touching the most sensitive part of your exposed body.

Refractive Surgery

Refractive surgeries for myopia such as LASIK are no more appropriate than glasses or contacts. In all such surgeries and procedures, the cornea is artificially altered to focus light rays on the retina. The main problem is they ignore the strain of improper use of the eyes that causes them to go out of focus in the first place. After surgery, the person of course continues to use his eyes wrongly, and the problems will return sooner or later. Tired eyes and other symptoms of strain won't go away with surgery. It's not the magic cure it's made out to be any more than contacts are.

In refractive surgeries, the eye is treated as a mechanical part of the body that's supposed to be indifferent to the abuse inflicted upon it to change its focus. Regardless of the ever-increasing technology employed, no human tissue will ever respond well to having layers burned off of it as if it were a steel object. The idea is great, but the context is completely inappropriate. Anyone seriously considering surgery should check out the Surgical Eyes website for descriptions of what to expect. It isn't merely a small risk of a complication during the surgery; it's a strong probability in favor of you ending up with one or more of the common complications, indefinitely, regardless of how skilled the doctor is. Even with serious post-surgery issues, you will still be considered a "success" as long as you can read 20/30 on the eye chart. The long-term effects of laser surgery are also unknown, as it's still a young procedure.


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