Visual acuity (medically: visus) corresponds to the resolution capacity of the eye. The resolution capacity is the ability of the retina to perceive two points as separate.
Visual acuity depends on the adaption luminance and the contrast. Increasing adaption luminance will also lead to increasing visual acuity. For surface inspection, this means that high ambient brightness positively influence the employees’ visual acuity.
Seeing and recognition is highly relevant for surface inspection. The eye not only distinguishes brightness contrasts, but also, for example, color contrasts.