Final answer:
The bottom half of the Anomaloscope target is associated with red-green color vision and is used to test for color blindness. It is a mixture field with two extremes of pure red and pure green. When the knob is turned, the color perception changes while the ratio of red to green light remains constant.
Step-by-step explanation:
The bottom half of the Anomaloscope target is associated with red-green color vision and is used to test for color blindness. This is a mixture field as it involves a combination of different colors. The two extremes of this target are pure red and pure green. When the knob is turned, the intensity of the red and green lights can be adjusted, which changes the color perception. However, the ratio of red to green light is constant when the knob is turned.
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