For lats two years I have this unusual eye symptom in my left eye. Did
a lot tests (examination by eye\neurology expert, brain scan, catarct,
heart ekg, etc.) but doctors can find anything wrong with my left eye.
Meanwhile, I had cataracts removed from both eyes in last two weeks,
and I still have the same symptom in my left eye.

Here is what happens. If I cover my right eye (my dominant eye) and
stare at, say, computer monitor or TV or a wall, I  begin see a curtain
coming over from the right side and blotting out the vision. It appears
that the curtain is actually my hand covering my eye. If I close that
right eye, than the curtain is just blacknes. I can have this curtain
go ayaw if I make an effort to look at whatever I was seeing with my
left eye, i.e. computer monitor or TV or wall-whatever that I was
seeing. The coming of curtain from the right side is automatic, usually
few minutes after I begin staring with the left eye. But making the
curtain is at my will, I just have to make an effort to see with the
left eye.

Since, none of the doctors are finding anything wrong with the left
eye, I wondering if this is something that I am doing subconsciously (
or is it unconsciously?).

I can cover my left eye, I do not have that problem with my right eye.
I am wondering if I have some left eye problem, is it just left eye as
a not dominant eye issue, or mental.

Thanks for any information about this unusual symptom I have.

bj