FIELD: medicine.
SUBSTANCE: invention refers to ophthalmology and can be used for spatial frequency optic canal examination for pass band. Measurements are two-staged and involve light blinking shown to the patient at preset initial frequency 10 Hz, and then blinking at incremental frequency increased from initial or decrement frequency decreased from initial. According to the first stage measurement results once the patient evaluates a differential threshold of shown serially light blinking at initial and incremental frequencies and fixes the third incremental frequency of light blinking at this moment, a differential threshold ΔFi in Hz is calculated by formula: 
where Ti3 and Tinit are periods of light blinking in msec corresponding to the third incremental and initial frequencies. Upon the second-stage measurements once the patient evaluates a differential threshold of shown serial light blinking at initial and decrement frequencies and fixes the third decrement frequency of light blinking at this moment, a differential threshold ΔFd in Hz is calculated by formula 
where Tinit and Td3 are periods of light blinking in msec, corresponding to initial and the third decrement frequencies. The pass-band of spatial frequency optic canal is evaluated as an arithmetic average of differential thresholds of frequencies of light blinking calculated within the first and second stage measurements.
EFFECT: method allows reducing an instrumental error in spatial frequency optic canal examination for pass band.
1 ex, 1 dwg
