Monocular trial frame.
D005123:Eye; D005139:Eyeglasses; D006801:Humans; D009801:Oculomotor Muscles / Q000502:physiology*; D012029:Refraction, Ocular; D014787:Vision Tests; D014785:Vision, Ocular
EYEGLASSES; MUSCLES, OCULOMOTOR/physiology; REFRACTION, OCULAR