ABO NOCE Basic Opticianry

Answer: C - There is no nose rest on a lensometer, therefore it does not need maintenance.

Periodically you should check the ink well to add more if necessary. The marker needle should also be cleaned off to avoid a buildup of excess ink.

All lensometers should also be cleaned and calibrated periodically by a professional to make sure they stay in working order and continue to be accurate.