Ryan, 16, was discharged from Green Lane Hospital eye clinic this week after having treatment 24 hours a day for three weeks.
"My vision is still very blurry but the colours are okay," Ryan told the Herald on Sunday.
"I am also really sensitive to light because the drops make my pupil big."
Doctors say the long term effect is still uncertain. He could need a year to a year to recover, and has to have six different types of drops in his eyes every half hour.
Ryan was carrying a bottle of concentrated hydrochloric acid.
When he went to place it on a table, the stopper came loose and the bottle fell to the floor.
Ryan's mother, Roz Edwards, has complained to the school and said it was the duty-of-care for the teacher to ensure all students were safe and that the school's policy of wearing safety goggles was enforced.
"I was told students were encouraged to wear safety goggles but did not have to if they wore prescription glasses," she said.
"Ryan doesn't wear glasses but I would have thought it would be a requirement for all children to wear safety goggles, even over normal glasses."
Ryan's science partner, an international exchange student, also wasn't wearing goggles. He was not injured but the spilled acid dissolved his socks.
Edwards said she was shaking when she saw the extent of the injury to her son's eye and was upset at what she said was a lack of concern from the school.
She said the deputy principal visited Ryan in hospital only after she complained.
The Ministry of Business, Innovation and Employment will investigate the accident.
Board of trustees chairman Shane Blake said the school had almost completed an investigation.
"The school will use the results of the internal and ministry investigations to make any required improvements to classroom practices, post-accident response, and school policies and procedures."