Clinical Use

Clinical Use

by Shirley Yin-Piazza

Color Vision Deficiency

Color vision deficiency is the inability to distinguish certain shades of color. The term “color blindness” is also used to describe this visual condition, but very few people are completely color blind.

Most people with color vision deficiency can see colors, but they have difficulty differentiating between the following colors:
  • Particular shades of reds and greens (most common)
  • Blues and yellows (less common). People with blue-yellow deficiency frequently have red-green blindness too.

People who are totally color blind, a condition called achromatopsia, can only see things as black and white or in shades of gray.

Color vision deficiency can range from mild to severe, depending on the cause. It affects both eyes if it is inherited and usually just one if it is caused by injury or illness. In the majority of cases, genetics causes color deficiency.

About 8 percent of Caucasian males are born with some degree of color deficiency. Women are typically just carriers of the color-deficient gene, though approximately 0.5 percent of women have color vision deficiency.

Source: American Optometric Association


OPTEC PLUS Smart Vision Screener

  • Enables quick, thorough and repeatable results
  • User-friendly interface
  • An expanded library of tests with limitless customization including auto-mode, randomization and protocols

Optec 900 Color Vision Screener

  • Preferred color blindness test
  • Simulates colored signal lights used in various occupations
  • Reduces the risk of passing those who might make errors with signal lights

Original Ishihara Color tests

  • For congenital red-green color blindness
  • Multiple colored plates making up several test designs
  • Each plate is printed with a circle made of many different sized dots, slightly different colors, spread in random
  • Color plates encased in a specially designed album type book for ease of handling