DH has short sight and wears glasses. This week he has started to complain that he cannot focus on a tv or computer screen using both eyes, so he closes one , but now what is happening is that if he looks through either eye separately the image is stable, but then when he tries stereo vision he gets double or fractured sight. After a while this settles down. Does anyone know what this might be please? he is due to fly on holiday skiing on Sunday and I can't get an optician's appointment until Saturday morning. I would really love to know if anyone can put my mind at rest please?