Amsler's grid is used to evaluate
The Amsler grid is a tool that eye doctors use to detect vision problems resulting from damage to the macula (the central pa of the retina) or the optic nerve. The damage may be caused by macular degeneration or other eye diseases, so the Amsler grid is useful in detecting these problems. Reference: AK khurana 7th edition
Central 10 degress of vision
Central 20 degrees of vision
Peripheral vision
Lens opacity
Anatomy, Development and clinical examination