Apparently, some aspects of my binocular vision still need to be developed.
One thing I noticed is that I haven't really learned to focus on things with both eyes, particularly in the case of small objects such as a pen or a finger. I may somewhat fuse a sufficiently large cup. However, if I am trying to look at a finger or a pen, I see it with my right or my left eye as before. If my eyes switch when I am looking at a pen, the pen moves a considerable distance. Thus, the background is fully fused and three-dimensional, yet a particular object inside this three-dimensional space can be seen with just one eye, as before.
If the object is at least several inches in diameter and sufficiently easy to see and track, then I can focus on it with both eyes. Perhaps most of the object will still be seen with just one eye, but at least the boundary of the object will be fused, thus the object appears to be in focus. If the object is sufficiently small or complicated, then both eyes do not even stay on the same object, and one eye start deviating immediately. This is quite uncomfortable, and if there is enough strain, one of the eyes gets suppressed more and more, and deviates further and further, and eventually binocular vision disappears. Reading is a little tricky, since I am not even close to fusing two images full of fine print that have to be aligned exactly right for the fusion to happen.
On the other hand, if at least the outline of the object can be seen with both eyes, then tracking the object is generally fun and seems to improve convergence. It helps if the object looks the same from different angles and is of a fairly homogeneous color, like the ball from yesterday or the water in a cup, so that misalignments do not prevent fusion.
Fundamentally this should be normal experience with only a quantitative difference. Probably, every person focusing on an object sees a small patch of this object with one eye only, and this eye is called dominant. This patch is then seen equally well in its entirety. According to Bates, trying to see an object equally well leads to strain. I guess, this is because in order to see, say, a small letter all equally well, the eyes have to look at the opposite ends of the letter, and this creates strain. On the contrary, if one can see or imagine a very small perfectly black dot, this leads the eyes to converge very closely, thus reducing strain.
Bates was writing that one should see a letter one is looking at than a letter that one is not looking at. If this does not happen, then Bates explained that this is cause by strain that should be relaxed, and suggested to try two objects further apart. This agrees with my understanding. If the area of the focused part of a binocular vision that is seen with only one eye includes two letters, then it is possible that one will be seen better than the other. After "more relaxation", that is, after more convergence is achieved, the letter that was previously seen better will go into the fused periphery (every focus has its periphery, there is no clear distinction) and thus will become seen worse than the letter that we wanted to look at.
First conclusion: much of the Bates method is for people with binocular vision.
Second conclusion: binocular vision starts from big objects, not from small objects. It is not necessary to be able to fuse a flower or track a pen with both eyes to have some degree of binocular vision.
Third conclusion: convergence exercises with following a pen or a finger are only for people who are already doing pretty well, that is, who are able to see a pen with both eyes. Otherwise they will be tracking the pen with one eye only.
One thing I noticed is that I haven't really learned to focus on things with both eyes, particularly in the case of small objects such as a pen or a finger. I may somewhat fuse a sufficiently large cup. However, if I am trying to look at a finger or a pen, I see it with my right or my left eye as before. If my eyes switch when I am looking at a pen, the pen moves a considerable distance. Thus, the background is fully fused and three-dimensional, yet a particular object inside this three-dimensional space can be seen with just one eye, as before.
If the object is at least several inches in diameter and sufficiently easy to see and track, then I can focus on it with both eyes. Perhaps most of the object will still be seen with just one eye, but at least the boundary of the object will be fused, thus the object appears to be in focus. If the object is sufficiently small or complicated, then both eyes do not even stay on the same object, and one eye start deviating immediately. This is quite uncomfortable, and if there is enough strain, one of the eyes gets suppressed more and more, and deviates further and further, and eventually binocular vision disappears. Reading is a little tricky, since I am not even close to fusing two images full of fine print that have to be aligned exactly right for the fusion to happen.
On the other hand, if at least the outline of the object can be seen with both eyes, then tracking the object is generally fun and seems to improve convergence. It helps if the object looks the same from different angles and is of a fairly homogeneous color, like the ball from yesterday or the water in a cup, so that misalignments do not prevent fusion.
Fundamentally this should be normal experience with only a quantitative difference. Probably, every person focusing on an object sees a small patch of this object with one eye only, and this eye is called dominant. This patch is then seen equally well in its entirety. According to Bates, trying to see an object equally well leads to strain. I guess, this is because in order to see, say, a small letter all equally well, the eyes have to look at the opposite ends of the letter, and this creates strain. On the contrary, if one can see or imagine a very small perfectly black dot, this leads the eyes to converge very closely, thus reducing strain.
Bates was writing that one should see a letter one is looking at than a letter that one is not looking at. If this does not happen, then Bates explained that this is cause by strain that should be relaxed, and suggested to try two objects further apart. This agrees with my understanding. If the area of the focused part of a binocular vision that is seen with only one eye includes two letters, then it is possible that one will be seen better than the other. After "more relaxation", that is, after more convergence is achieved, the letter that was previously seen better will go into the fused periphery (every focus has its periphery, there is no clear distinction) and thus will become seen worse than the letter that we wanted to look at.
First conclusion: much of the Bates method is for people with binocular vision.
Second conclusion: binocular vision starts from big objects, not from small objects. It is not necessary to be able to fuse a flower or track a pen with both eyes to have some degree of binocular vision.
Third conclusion: convergence exercises with following a pen or a finger are only for people who are already doing pretty well, that is, who are able to see a pen with both eyes. Otherwise they will be tracking the pen with one eye only.
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