They focus into your retina, which is small, but not pinhead small. The length they sit away fron your eyes is part of it. You could take them off and get that focal point to be concentrated in much smaller area.
The retina is not as small as a pinhead, but the light from any source doesn’t get focused over the whole thing, it gets focused to a point. Anything else would mean the image is blurred, defeating the point of the glasses.
They focus into your retina, which is small, but not pinhead small. The length they sit away fron your eyes is part of it. You could take them off and get that focal point to be concentrated in much smaller area.
The retina is not as small as a pinhead, but the light from any source doesn’t get focused over the whole thing, it gets focused to a point. Anything else would mean the image is blurred, defeating the point of the glasses.