Convergence Facility Inspection

Operation Steps: 

(1) Complete correction of ametropia.

(2) Insert 3△ BI (base in) and 12△ BO (base out) into the flipper, and adjust the pupillary distance.

(3) Ask the subject to look at the 40 cm single-row vision mark, place the 3△ BI (base in) in front of the subject, and fuse the visual marks into one column.

(4) Place 12△ BO (base out) in front of the subject and start timing.

(5) Ask the subject to look at the 40 cm single-row visual mark with both eyes and try to fusion image. After the fusion of binocular visual mark, switch the 3△ BI (base in) again until the binocular fusion, which is a switching cycle.

(6) The measured eye completes several switching cycles within one minute.

(7) The normal value of the population and the convergence facility of normal eyes are 12 ~ 18 times per minute.