Book with 10 plates for illiterates. Testing for color deficiency requires a high degree of sensitivity and specificity. This series of plates is intended to detect color blindness and color blindness from an early age in people who cannot read. The plates are designed with simple geometric shapes, because the subjects may not be able to understand complex pieces. The test provides a rapid and accurate assessment of a color vision deficiency of congenital origin.

In most cases, a red-green deficiency is diagnosed, which can be of two types:
- protan, which can be absolute (protanapia) or partial (protanomalia)
- deutan, which can be absolute (deuteranopia) or partial (deuteranomaly)

No. 1. Recognizable as a circle by both the normal and the abnormal.
No. 2. Recognizable as a square by both the normal and the abnormal.
No. 3. Recognizable as a circle by the normal, but usually as a square by the abnormal.
No. 4. Recognizable as a square by the normal, but usually as a circle by the abnormal.
No. 5. Recognizable as a curved line by both the normal and the abnormal.
No. 6. When tracing the curving line between the upper left marker x and the lower right marker x, the normal traces the red curve, but the abnormal usually traces the blue.
No. 7. When tracing the curving line between the upper left marker x and the lower right marker x, the normal traces the upper green curve and the abnormal usually traces the lower red curve.
No. 8. Starting at the upper left marker x, the normal can trace the upper and lower curves and return to the starting marker. In the case of the abnormality, some can trace either the upper red line or the lower red purple curve. Where the deviation is only slight, some patients can trace both correctly. In a very small number of cases, the abnormal subject recognizes neither.