The Duochrome Effect

The Duochrome Effect is a phenomenon used in eye exams to determine your corrective lens prescription. It works on how your eyes perceive different colors—red and green. When looking through the eye chart, if letters on the red background appear clearer, you may need a different correction than if green looks sharper. This is because your eye's focusing ability interacts differently with these colors. The test helps optometrists fine-tune lenses by balancing your focus so that letters on both backgrounds appear equally sharp, ensuring optimal clarity and vision correction.