The response AC/A ratio: differences between inducing and relaxing accommodation at different distances of fixation.

Purpose: To determine if there is a difference between the response AC/A ratios when measured using the gradient method at near and distance fixation with plus and minus lenses respectively in young adults with normal binocular single vision.

Methods: A repeated measures design was used. The accommodative response of the right eye was measured objectively using the Shin-Nippon SRW-5000 autorefractor (Grand Seiko Company, Fukuyama, Japan) (open view) at 33 cm with and without plus lenses (2DS or 3DS) and at 3.