CBT - Color Blindness Test

This is an Color Blindness Test (CBT) app, which use the the Ishihara Color Test to test peoples's color perception.
The Ishihara Color Test was named after its designer, Dr. Shinobu Ishihara, a professor at the University of Tokyo.
The test consists of a number of colored plates, called Ishihara plates, each of which contains a circle of dots appearing randomized in color and size. Within the pattern are dots which form a number or shape clearly visible to those with normal color vision, and invisible, or difficult to see, to those with a red-green color vision defect, or the other way around. The full test consists of 38 plates, but the existence of a deficiency is usually clear after a few plates. There is also the smaller test consisting only 24 plates. This app is an 24-plates test.
The plates make up several different test designs:
- Transformation plates: individuals with color vision defect should see a different figure from individuals with normal color vision.
1) Vanishing plates: only individuals with normal color vision could recognize the figure.
2) Hidden digit plates: only individuals with color vision defect could recognize the figure.
3) Diagnostic plates: intended to determine the type of color vision defect (protanopia or deuteranopia) and the severity of it.