Study
Study lessons
Short topic lessons that teach the method before you drill it. Each one works an example the way the exam expects, then links straight to the calculator, drill or lab that practises it.
- ABO / NCLE
Lens optics
Plus and minus lenses, transposition, spherical equivalent, the optical cross, Prentice’s rule and vertex distance, worked the way the exam expects.
Read the lens optics lesson - ABO
Frames and measurements
The boxing system, frame PD, decentration, minimum blank size and segment placement: the measurements behind every pair of glasses.
Read the frames and measurements lesson - ABO
Dispensing and verification
Checking finished glasses against the ANSI Z80.1 tolerances, impact testing, vertical imbalance and the everyday frame adjustments.
Read the dispensing and verification lesson - NCLE
Contact lens fitting
From K readings to a finished order: base curve, spectacle-to-CL power, corneal and residual astigmatism, SAM-FAP, LARS, fluorescein patterns and over-refraction.
Read the contact lens fitting lesson - ABO / NCLE
Ocular anatomy
The eye from front to back, the five corneal layers, the three-layer tear film and the tear tests, with the refractive indices the exams ask about.
Read the ocular anatomy lesson - ABO / NCLE
Refractive conditions and eye disease
Presbyopia, anisometropia and the binocular conditions, then the common eye diseases an optician must recognise and refer.
Read the refractive conditions and eye disease lesson