How to understand it
The record may use a total or separate right and left values. Ask whether it is for distance or near viewing.
An example
A total of 63 mm can be 31 + 32 mm; dividing by two would lose the asymmetry in this teaching example.
A common mix-up
PD is not lens power, and a total value does not automatically replace monocular measurements.
See the idea in a full guide →
Sources & verification
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