What is the method to test red and green color weakness

1.

The test chart used by this method consists of different color spots of the same brightness. Normal people can distinguish specific images according to color, while red and green color weakens cannot distinguish.

2. The hue arrangement method The

doctor will arrange the objects of the same shape and size but different colors in order, so that the examinee can select the object with the closest color. If it cannot be selected, it is

red and green color weakness.3.