Correct

验光

/ yànguāng / 
Strokes

Definition

optometry/to examine the eyes

Example

As a Verb

have one's eyesight tested

1
Diànnǎo
电脑
yànguāng
验光

computer optometry

2
Yànguāng
验光
pèijìng
配镜

have one's eyesight tested for spectacles

As a Noun

optometry