Optics
30%of exam
Ocular Anatomy + Refraction
33%of exam
Ophthalmic Products
10%of exam
FramesCoatingsPhotochromicSafety eyewearLow vision
Instrumentation
9%of exam
LensometerLens clockDistometerPupilometerDigital/3D
Dispensary Protocols
10%of exam
PD/OCFrame fittingAdjustmentTroubleshootingSOAP
Laws + Regulations
8%of exam
ANSI Z80.1ANSI Z87.1FDA impactFTC EyeglassState licensure
Quick Facts
- Exam
- ABO-AC
- Credential
- ABOC-AC
- Time
- 180 min
- Pass
- Modified Angoff
- Questions
- 125 MCQ
- Fee
- $225
- Blueprint
- Aug 2024
Lens Material Index
CR-39=1.50 | Poly=1.586 | 1.74=thinnest
CR-39: 1.50Poly: 1.586Trivex: 1.531.74: thinnest
CR-39 vs Polycarbonate
CR-39
- Cheapest plastic
- Abbe 58 (clear)
- Brittle/impacts
Polycarbonate
- Impact resistant
- Abbe 30 (CA)
- Thinner/lighter
Clarity vs safety
Lens Material Picker
- High minus Rx→High-index 1.74(Thinnest edge)
- Children/safety→Polycarbonate(Impact resistant)
- Rimless drill→Trivex(Will not crack)
- Budget/low Rx→CR-39(Optical clarity)
- High astigmatism→High-index 1.67(Better optics)
- Safety eyewear→Poly/Trivex(ANSI Z87.1)
- AR pairing→Glass/high-index(High Abbe)
Lens Materials
- CR-39
- n=1.50 | Abbe 58Cheap
- Polycarbonate
- n=1.586 | Abbe 30Impact
- Trivex
- n=1.53 | Abbe 43Light
- High-index 1.60
- n=1.60 | Abbe 41
- High-index 1.67
- n=1.67 | Abbe 32
- High-index 1.74
- n=1.74 | Abbe 33Thin
- Glass crown
- n=1.523 | Abbe 59
Prentice's Rule
Prism = decentration(cm) x power(D)
c = cmF = dioptersDelta = c x F
Polycarbonate vs Trivex
Polycarbonate
- n=1.586 thinner
- Abbe 30 (CA)
- Softer/scratches
Trivex
- n=1.53
- Abbe 43 (clearer)
- Lightest/impact
Thin vs clarity
Ophthalmic Formulas
- Prentice's Rule
- Prism = c x F
- Vertex distance
- Compensate >4D
- Martin's tilt
- Tilt changes power
- Sagittal depth
- Surface sag formula
- Focal length
- f = 1/F (m)
- Surface power
- F = (n-1)/r
- Spectacle magnification
- Power x shape
Abbe Values (higher=clearer)
Glass 59 | CR-39 58 | Trivex 43 | Poly 30
Glass: 59CR-39: 58Trivex: 43Poly: 30
High-Index vs Polycarbonate
High-index 1.74
- Thinnest minus
- Abbe 33 (some CA)
- Costs more
Polycarbonate
- Impact resistant
- Thicker edge
- Abbe 30 (more CA)
Thin vs safety
Prism + Decentration
- Base direction
- Thickest edge
- Split prism
- Split between eyes
- Compounded prism
- Two prisms combined
- Resolved prism
- Horizontal + vertical
- Induced prism
- Decentering off-OC
- Prism diopter
- 1cm dev at 1m
- Slab-off
- Base up on minus
Lens Design
- Aspheric
- Flattened periphery
- Atoric
- Aspheric cyl too
- Progressive
- Continuous add corridor
- Slab-off
- Vertical imbalance fix
- FT bifocal
- Flat-top 28
- Trifocal
- Intermediate + near
- Tscherning's ellipse
- Base curve range
Ocular Anatomy
- Cornea
- Clear front window
- Crystalline lens
- Accommodation
- Retina
- Image capture
- Fovea
- Sharpest vision
- Iris/pupil
- Light control
- Ciliary body
- Aqueous + focus
- Extraocular muscles
- Six EOMs
- Cranial nerves
- II, III, IV, VI
Refractive Errors
- Myopia
- Eye too long
- Hyperopia
- Eye too short
- Astigmatism
- Corneal curve uneven
- Presbyopia
- Lens hardens (age)
- Anisometropia
- Unequal Rx eyes
- Aniseikonia
- Image size differs
Ocular Pathology
- Cataracts
- Lens opacifies
- Glaucoma
- High IOP damage
- Keratoconus
- Cornea thins/cones
- Diabetic retinopathy
- Retinal vessel leak
- AMD
- Macula degenerates
- Strabismus
- Eye misalignment
- Homonymous hemianopia
- Visual field loss
Glass vs Plastic
Glass
- Abbe 59 (no CA)
- Heavier
- Shatters (unsafe)
Plastic CR-39
- Lighter
- Abbe 58
- Needs coating
Optics vs safety/weight
Progressive Design Picker
- First-time wearer→Soft design(Less swim)
- Experienced/active→Hard design(Wider channels)
- Computer/office→Office progressive(Wider intermediate)
- Short fitting height→Short-corridor(14 mm min)
- Wrap frame→Free-form compensated(Position of wear)
- Anisometropia→Slab-off progressive(Vertical balance)
Frames + Coatings
- AR coating
- Destructive interference
- Photochromic
- UV darkens lens
- Polarized
- Blocks reflected glare
- Tints
- Absorbs specific light
- Titanium
- Light/hypoallergenic
- Rimless
- Drilled mount
- Safety eyewear
- ANSI Z87.1
- Low vision aids
- Magnifiers/CCTV
Lensometer vs Lens Clock
Lensometer
- Back vertex power
- Verifies Rx
- Locates OC/prism
Lens clock
- Surface curvature
- Calculates sag
- No power read
Power vs curvature
Instruments
- Lensometer
- Measures lens power
- Lens clock
- Surface curvature
- Distometer
- Vertex distance
- Pupilometer
- PD measurement
- Keratometer
- Corneal curvature
- Digital/3D
- Auto-measure system
Complaint Troubleshooter
- Blur at distance→Check OC/tilt(Tilt induces power)
- Reading blur→Verify add/near PD(Segment height)
- Swim/dizziness→Reduce pantoscopic(Or change design)
- Temples pinch→Adjust temple bend(Behind ears)
- Glasses slip→Adjust nose pads(Or temple length)
- Edge thickness→Re-select material(Higher index)
Dispensing Protocols
- PD
- Pupillary distance
- OC height
- Optical center height
- Pantoscopic tilt
- Lens forward tilt
- Wrap compensation
- Curved frame Rx
- Frame adjustment
- Temple/bridge fit
- SOAP
- Subj/Obj/Assess/Plan
- Minimum blank size
- Smallest lens cut
ANSI Z80.1 Tolerances
Power 0.25 D | axis 5 deg | prism 0.5
Sphere/cyl: 0.25DAxis: 5 degPrism: 0.5 delta
Basic vs Advanced ABO
Basic ABO NOCE
- Entry-level
- 2 hr exam
- Dispensing focus
Advanced ABOC-AC
- 3 yr recert first
- 3 hr exam
- Complex optics/path
Entry vs mastery
Standards + Regulations
- ANSI Z80.1
- Rx ophthalmic tolerances
- ANSI Z87.1
- Safety eyewear standard
- FDA impact
- Drop-ball resistance
- FTC Eyeglass Rule
- Rx release required
- State licensure
- Varies by state
- Universal precautions
- Infection control
FTC vs FDA Rules
FTC Eyeglass Rule
- Rx release required
- Auto Rx expiration
- Patient copy right
FDA impact
- Drop-ball test
- Impact resistance
- Eyewear safety
Prescription vs safety
Common Traps
Vertex distance
Plus closer = stronger ≠ Minus closer = weaker
Prism direction
Base = thickest edge ≠ Plus prism: toward OC
Slab-off direction
Always base up ≠ On more minus lens
Abbe vs index
High index = low Abbe ≠ Low Abbe = CA
Photochromic vs polarized
Photochromic = UV-activated ≠ Polarized = glare filter
PD monocular vs binocular
Mono = each eye ≠ Binoc = total
ANSI vs exact
Tolerance bands apply ≠ Not exact match
Last Minute
- 1.Six content domains, unequally weighted
- 2.125 Q | 3 hr | $225
- 3.Pass = Modified Angoff
- 4.Prentice: Delta = c x F
- 5.Vertex: compensate >4D
- 6.Slab-off = base up
- 7.ANSI Z80.1 = Rx; Z87.1 = safety
- 8.FDA = impact; FTC = Rx release
- 9.AR = destructive interference
- 10.Poly = impact; 1.74 = thinnest
- 11.Abbe high = clearer; low = CA
- 12.Pantoscopic tilt induces power
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