Colour blindness test. Card being used to check for red-green colour blindness. The Ishihara test,which uses pseudoisochromatic plates,is the most widely used. This card depicts a line of orange dots on a background of blue dots. People with normal vision can trace the entire line. People with red-green colour blindness are unable to distinguish the line and therefore cannot complete the task. Colour blindness is usually caused by an inherited genetic defect in the light-sensitive pigments of the eye,but it can be caused by optic injury or nerve diseases | |
Lizenzart: | Lizenzpflichtig |
Credit: | Science Photo Library / ANNABELLA BLUESKY |
Bildgröße: | 4176 px × 4176 px |
Modell-Rechte: | vorhanden |
Eigentums-Rechte: | nicht erforderlich |
Restrictions: | - |