20 CFR § 404.1581 - Meaning of blindness as defined in the law.
We will consider you blind under the law for a period of disability and for payment of disability insurance benefits if we determine that you are statutorily blind. Statutory blindness is defined in the law as central visual acuity of 20/200 or less in the better eye with the use of correcting lens. An eye which has a limitation in the field of vision so that the widest diameter of the visual field subtends an angle no greater than 20 degrees is considered to have a central visual acuity of 20/200 or less. Your blindness must meet the duration requirement in § 404.1509. We do not consider certain felony-related and prison-related impairments, as explained in § 404.1506.