What is the Duochrome test used for || Why do opticians use red and green?

A duochrome test is a test commonly used to refine the final sphere in refraction
What is the Duochrome test used for || Why do opticians use red and green?
What is the Duochrome test used for || Why do opticians use red and green?
What is the Duochrome test used for || Why do opticians use red and green?

duochrome,