noun
emmetropia
Medical term for normal vision where light focuses correctly on the retina without corrective lenses.
正視眼の人は、遠くも近くもはっきり見える。
People with emmetropia can see both far and near clearly.
遠視 is farsightedness (hyperopia), where close objects appear blurry, while 正視眼 is normal vision.
Compound of 正 (correct) + 視 (vision) + 眼 (eye), literally 'correct-vision eye'. A modern medical coinage.