Instruments, Regulations and Math
Optical Instruments
The lensmeter reads lens power, axis, add, prism, and optical center. Pupillometers measure PD, distometers measure vertex distance, and a lens clock measures surface curvature.
Impact Resistance and Standards
The FDA requires dress lenses to be impact resistant, historically shown by the drop-ball test. ANSI Z80.1 governs dress eyewear tolerances; ANSI Z87.1 governs occupational safety eyewear.
HIPAA and Professional Ethics
Opticians handle protected health information and must keep prescriptions and records confidential under HIPAA. Ethics require verifying questionable prescriptions and maintaining hygienic, calibrated equipment.
Core Optical Math
Optical math underlies verification and fitting: Prentice's rule for prism, transposition, spherical equivalent, decentration, and minimum blank size. These calculations recur throughout dispensing.
Minimum Blank Size and Compensation
Minimum blank size ensures a lens blank is large enough to cut out after decentration. Vertex compensation adjusts ordered power when the fitted vertex differs from the refracted vertex.
Last updated: July 2026