D: Aust. Standards - Week 9 Flashcards
How many experts (technical, business, academia, govt, and community experts) create standards?
It’s over 9000!
What is the most important australian standards guide for us to remember?
AS/NZS ISO 21987: 2011 Ophthalmic Optics - Mounted Lens
Name 5 aspects of mounted lenses that need to conform to Australian standards
- Optical: power, axis, prism, near addition
- Thickness and positioning
- Material and surface quality
- Markings
- Special requirements: tings, coatings, photochromatic materials etc.
Name 5 ways the material and surface quality of a mounted lens needs to conform to Australian standards
- Must have no visible defects internally or on the finished surface in the central zone
- Must have a smooth regular bevel and safety chamfer; and no chips or cracks
- No gaps should be present between the frame and lenses
- Lenses should match in shape, size and appearance (tint, ARC, mirror)
- Mounted lenses should be secured in position but not under excessive strain: no “warping” (surface astig over 1D)
What is a safety chamfer?
It’s basically when you smooth off all the edges
How big are the central zones for the following frames?:
A: SVs
B: Bifocal/Trifocal
C: PALs
All are 30m
Where are the central zones centred for bifocals/trifocals?
- around DRP (distance reference point) OR, if segment less than 30mm
- either whole segment or NRP
Between the higher absolute back vertex powers of 0-3 diopters: What is the tolerance for SVs/Multi?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.12
B: 0.09
C: 0.12
D: 0.18
E: —
Between the higher absolute back vertex powers of 3-6 diopters: What is the tolerance for SVs/Multi?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.12
B: 0.12
C: 0.12
D: 0.18
E: 0.25
Between the higher absolute back vertex powers of 6-9 diopters: What is the tolerance for SVs/Multi?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.12
B: 0.12
C: 0.18
D: 0.18
E: 0.25
Between the higher absolute back vertex powers of 9-12 diopters: What is the tolerance for SVs/Multi?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.18
B: 0.12
C: 0.18
D: 0.25
E: 0.25
Between the higher absolute back vertex powers of 12-20 diopters: What is the tolerance for SVs/Multis?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.25
B: 0.18
C: 0.25
D: 0.25
E: 0.25
Between the higher absolute back vertex powers of over 20 diopters: What is the tolerance for SVs/Multis?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.37
B: 0.25
C: 0.25
D: 0.37
E: 0.37
Between the higher absolute back vertex powers of 0-3 diopters: What is the tolerance for PALs?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.12
B: 0.12
C: 0.18
D: 0.18
E: 0.25
Between the higher absolute back vertex powers of 3-6diopters: What is the tolerance for PALs?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.18
B: 0.18
C: 0.18
D: 0.18
E: 0.25
Between the higher absolute back vertex powers of 6-9 diopters: What is the tolerance for PALs?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.18
B: 0.18
C: 0.18
D: 0.18
E: 0.25
Between the higher absolute back vertex powers of 9-12 diopters: What is the tolerance for PALs?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.18
B: 0.18
C: 0.18
D: 0.25
E: 0.25
Between the higher absolute back vertex powers of 12-20 diopters: What is the tolerance for PALs?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.25
B: 0.18
C: 0.25
D: 0.25
E: 0.25
Between the higher absolute back vertex powers of over 20 diopters: What is the tolerance for PALs?
A: The back vertex power of each principle meridian?
B: Cyl power between >0 and <0.75D
C: Cyl power between >0.75D and <4D
D: Cyl power between 4D and 6D
E: Cyl power over 6D
A: 0.37
B: 0.25
C: 0.25
D: 0.37
E: 0.37
How does tolerance for cylinder axis vary with cyl power?
As cyl power increases, tolerance for cyl axis gets stricter
What is the cyl axis tolerance for the following cyl powers?
A: >0.125-<0.25
B: >0.25-<0.50
C: 0.50-0.75
D: 0.75-1.50
E: 1.50-2.50
F: Over 2.50D
A: 15
B: 9
C: 6
D: 4
E: 3
F: 2
What are the tolerances for add power for the following add powers:
A: less than or equal to 4.00D add
B: Over 4.00D add
A: 0.12
B: 0.18
For the higher absolute ordered component prism value between 0-2 diopters, what is the tolerance of:
A1: horizontal component - for powers b/w 0-3.25
A2: horizontal component - for powers over 3.25
B1: vertical component - for powers b/w 0-5.00
B2: vertical component - for powers over 5.00
A1: 0.67 prism diopter
A2: 2mm displacement
B1: 0.50 pd
B2: 1mm displacement
For the higher absolute ordered component prism value between 2-10 diopters, what is the tolerance of:
A1: horizontal component - for powers b/w 0-3.25
A2: horizontal component - for powers over 3.25
B1: vertical component - for powers b/w 0-5
B2: vertical component - for powers over 5.00
A1: 1.00 prism diopter
A2: 0.33 pd + 2mm displacement
B1: 0.75 pd
B2: 0.25 + 1mm displacement
For the higher absolute ordered component prism value over 10 diopters, what is the tolerance of:
A1: horizontal component - for powers b/w 0-3.25
A2: horizontal component - for powers over 3.25
B1: vertical component - for powers b/w 0-5
B2: vertical component - for powers over 5.00
A1: 1.25 pd
A2: 2mm displacement
B1: 1 pd
B2: 0.25 + 1mm displacement
What are the tolerances for surface power in:
A: individual lens
B: Difference b/w lenses
A: 0.50
B: 0.25
What is the tolerance for lens thickness specified by the manufacturer?
0.3mm
What are the Australian standard requirements for tints and transitions? (3)
- even density/uniformity of colour
- UV and luminous transmittance must not be less than or equal to 3% (or 8% when driving, or 75% at night)
- colorisation limits (red and violet factors)
What are the Australian standard tolerances for Anti-Reflective coatings?
Reflectance must be less than 2.5% and not differ from specification by over 20%
What factors involved with the surface coating must be accounted for in Australian standards? (4)
- appearance
- adhesion
- chemical stability
- thermal stability
What specific tests can you perform on spectacle frames? (6)
- endurance
- corrosion
- bridge strength
- flammability
- colour change with optical radiation
- nickel release
What are the important considerations for the segments in BFs/TFs and PALs?
- segments should match in size, shape and orientation
- dividing line/reference line not tilted >2deg
- horizontal and vertical decentration should be within 1mm inclusive