Types of Color Vision Tests

A color vision test is a way to determine whether a person can discriminate between colors. Color blindness, also called poor color vision or color vision deficiency, doesn't mean that a person can't see color at all. In most cases he has a reduced ability to distinguish between certain colors. The most common form of color vision deficiency is red-green color deficiency, but some people have blue-yellow color deficiency.

Ishihara Color Vision Test

• The most common test for color vision is the Ishihara Color Vision Test. During the test, the participant is shown a pattern of seemingly random dots of various sizes and colors. A person with normal vision is able to distinguish a number in the middle of the dots, while a person with color vision deficiency can't see it, or can't see the same number that a person with normal vision can. According to All About Vision, the complete Ishihara Color Vision Test consists of 38 plates, but sometimes a smaller number of plates is included in a routine eye exam.

Arrangement Tests

• Another type of color vision test involves arranging a series of colors in order by hue. This type of test can assess whether a person has color vision deficiency and can also measure the severity of color vision defects. The Farnsworth -Munsell 100 Hue Test is the most common of this type of test. A smaller arrangement test is the Farnsworth-Munsell D15 Test. This test can determine if a person is color blind, but can't determine the severity of the problem.

Online Color Blindness Tests

• Some tests for color blindness are offered online. The quality of these tests varies. It is important for colors to be perfectly represented in order to achieve accurate results. Variations in lighting can also affect results. For the most accurate information, color blind tests need to be administered by a professional eye doctor under proper lighting.

Who Should Be Tested?

• Accurate color perception is needed in some types of work, such as commercial designers, artists and electricians. Color blind testing may be a prerequisite of these types of jobs. Many people who have poor color vision are unaware that they have a problem until other people point it out. A person that suddenly develops problems with color vision when she has always been able to see a full range of colors needs to see a doctor. Certain health problems such as cataracts may be diagnosed after a person notices sudden or gradual loss of the ability to identify colors.