Sonia's grandfather was not able to see clearly after returning from his walk on a bright sunny day. He was about to hit a chair when sonia held him and guided him to the nearby sofa. What could be the reason for sonia's grandfather not being able to see clearly on entering the house

Sonia's grandfather was not able to see clearly after returning from his walk on a bright sunny day. He was about to hit a chair when Sonia held him and guided him to the nearby sofa, in sunny environment grandfather's eye is set according to high brightness, his pupils become small to lower the number of light rays entering his eye, when he returned from sunny environment to his house which was having low brightness so the pupils should enlarge to absorb more light to see clearly but due to old age his Ciliary muscle of the eye would have worn out and due to this poor coordination the image was not clear.