Broadly these are the eyesight eligibility:
"The distance vision (corrected) should be 6/6 in better eye (6/9 in worse eye). Myopia should not be more than 2.5 D and hypermetropia not more than 3.5 D including Astigmatism. Internal examination of the eye will be done by means of opthalmoscope to rule out any disease of the eye. A candidate should have good binocular vision. The color vision standard will be (CP-III) for Army."

All three wings of the NDA has different eligibilty for physical standards and eyesight. Please click here for a detailed list of the specifications.