(1) Correct the far ametropia of both eyes completely, adjust the trial frame and the pupil distance on the rack set.

(2) According to the patient's age, the initial add of the patient is calculated by empirical method. 

The patient is 50 years old. Initial add = (50-32) × 0.1≈+1.75D。

(3) Add + 1.75D lens on the basis of the far diopter of the trial frame, and put the trial frame on the patient.

(4) Turn on the light and place the near vision chart at 40 cm to let the patient read out the best near vision.

(5) If the best near vision of the patient is 1.0, take the previous line of 0.8 visual markers. The examinee holds the positive rack set, and gradually increase the positive spherical lens until the examinee reports the fuzzy initial point, that is, the added positive spherical lens is the negative relative accommodation of the measured eye.

(6) Replace the negative rack set, focus on the upper line of the best vision, and gradually increase the negative spherical lens until the visual target of the tested eye is blurred, and the height of the added negative spherical lens is the positive relative accommodation of the tested eye.

CONVEX (+)

Retinoscopy Rack Set

CONCAVE (-)