Screening and quantitative color blindness tests

While screening tests can only find out a color vision problem, detailed quantitative tests can determine its severity. This article introduces two tests belonging to these two categories respectively.

Colored plates in different sizes are used to detect color blindness

During a comprehensive eye exam, patients will always receive the Ishihara Color Vision Test for detecting color blindness. Invented by the Japanese ophthalmologist Shinobu Ishihara, this test is currently the most widely applied screening test. The booklet of the test consists of typically 38 plates of many dots with various colors, brightness and sizes. Normal people can see clear numbers through these dots, which is beyond individuals with color blindness. Other abbreviated versions of this test take use of only 14 or 24 plates.

Use sequenced colored disks to determine color-blindness severity

For further color blindness test, a popular test named Farnsworth-Munsell 100 Hue Test is available. While simulating natural daylight via a viewing booth, this test requires a testee to arrange many disordered hues on disks into a gradually changing hue. All colored disks are numbered on the bottom in order to determine how closely the patient’s result matches the right sequence. According to the comparison outcome, his or her accurate color perception and severity of color blindness can be evaluated. These disks should be replaced every two years, in case of color saturation loss. A precise version named Farnsworth-Munsell D15 Test containing 15 colored disks is also created as another similar screening test.

The importance of tests for poor color perception or color blindness

Electricians, commercial artists, designers, technicians and certain manufacturing and marketing individuals always need accurate color perception for normal or better work performance. Color blindness is always congenital and many people are unaware of it in daily lives. Undetected color blindness or poor ability of color perception is quite dangerous during daily activities, e.g. crossing an intersection. It is very important to receive one of the above tests from an eye doctor once there is any indicating sign of color blindness.

Some tinted contact lenses can enhance color perception

The most critical factor involved in color perception tests in the exact color representation. Today, many people suspect the results performed by online color tests. It is widely acknowledged that color tests from eye doctors are more trustful, since they provide standard materials under proper lighting. Once the presence of color blindness is detected, getting a remedy to it is the following task. Treatment for this problem is similar in principle to compromising myopia and hyperopia. Color blindness can not be removed, and the feasible way is to get corresponding vision aid. It is exciting that special tinted contact lenses can improve people’s color perception abilities.