CL Verification

Question 1

What is CL verification

Answer 1

• confirm lenses match order
• make sure order is appropriate for rx

Question 2

Parameters to verify

Answer 2

• curvature
• central & peripheral
• diameter
• power
• thickness
• refractive index

Question 3

Why do we verify CLs

Answer 3

• maximise fitting success
• maximise profit
• ensure high standards
• determine source of problem

Question 4

When to verify CLs

Answer 4

• on receipt of cls
• during aftercare -warpage
• before reordering

Question 5

How to verify power of Rigid lens

Answer 5

• focimetry

Question 6

How to verify diameter

Answer 6

• v-slot gauge
• hand held magnifier

Question 7

How to verify lens thickness

Answer 7

• dial gauge

Question 8

How to measure the BOZR

Answer 8

• radiuscope - platform linked to a scale giving distance travelled in mm, uses drysdale theory
• keratometer - place lens on a prism, read curvature

Question 9

Edge profile verification - RGP

Answer 9

Instrument techniques
- projection magnifier
- ehrmann profilometer
- palm test
- radiuscope
- RGP edge moulding

Question 10

What is a toposcope

Answer 10

• measures BOZR and BPCR of RGP lenses
• measures spherical, toric and aspheric lens