A patient with a high spatial frequency cut-off of 40 cycles per degree will have what predicted Snellen acuity?

To determine the predicted Snellen acuity from a high spatial frequency cut-off of 40 cycles per degree, it is important to understand the relationship between spatial frequency and visual acuity. Spatial frequency, measured in cycles per degree (cpd), corresponds to the ability of the visual system to resolve fine details.

The typical conversion from cycles per degree to Snellen acuity is approximated by the formula that states an increase in spatial frequency results in improved visual acuity. A high spatial frequency cut-off of 40 cycles per degree indicates that the patient has excellent visual resolution capabilities. Generally, the higher the spatial frequency cut-off, the better the vision.

For reference, 30 cycles per degree is roughly associated with 20/20 visual acuity, so a cut-off of 40 cycles per degree implies superior visual acuity beyond what is conventionally regarded as normal (20/20). Therefore, the predicted Snellen acuity for a patient with a high spatial frequency cut-off of 40 cycles per degree is 20/15, which suggests that this patient can see at 20 feet what a person with normal vision would be expected to see at 15 feet. This represents a level of acuity that exceeds standard vision levels and indicates