Opt202 lecture 1 2019

OPT202 LECTURE 1
2019
Opticianry: Standards of Practice/
Guidelines/Bylaws
Frame Types, Materials & Parts –Chapter 1
Frame Measurements & Marking –Chapter 2
Standard Alignment – Chapter 8
History of Spectacles

Opticianry: Standards of
Practice / Bylaws /
Guidelines

College of Opticians of Ontario
Read the Standards of Practice and Bylaws
which are available at the link below:
http://www.coptont.org/docs/Legislation/Stan
dards_of_Practice.pdf

Standards of Practice
Purpose and Scope
 Outline the COO’s expectations for opticians’
conduct in practice
 Provide benchmarks which the COO can use to
measure opticians conduct
 Provide the public with an understanding of the
quality of care they should receive from an
optician
The Standards of Practice are reviewed every 3
years by the COO

Currently there are 7 standards
1. Competence
States the criteria under which opticians must conduct
themselves so the patient receives the most effective
standard of care.
2. Professional Conduct
Designed to ensure that opticians meet the legal and
ethical requirements of the profession
3. Dispensing of Appropriate Optical Devices
Outlines the criteria for opticians to dispense eyeglasses,
contact lenses & subnormal vision devices

4. Safety and Infection Control in the Practice
Environment
Opticians must take measures to minimize the risk of
contamination and transmission of infectious agents with
their practice.
5. Record Keeping
States what should be in a patient’s file, how long files must
be kept and outlines privacy requirements.
6. Patient Relations
Opticians must ensure the patient understands the
procedures they are undergoing. Confidentiality must be
maintained
7. Websites and Technology
Websites must comply with the Advertising Regulation and

Practice Guidelines
http://www.coptont.org/docs/Legislation/Prac
tice-Guidelines-09-28-15.pdf
 describe best practices for opticians
 explain and interpret standards of practice and
other responsibilities of an optician
 are a resource to help opticians understand how
to make safe and ethical practice decisions

Bylaws
 Articulate the composition of the COO Council
 Explain the council member’s duties
 State the registration fees for opticians, interns
and students
 Outline the procedures for council meetings
 Committee appointments and procedures
http://www.coptont.org/docs/Legislation/COO-By-
laws-July2016.pdf

Summary
When practicing opticianry in Ontario
 The Standards of Practice inform opticians
and the public what the expectations are
 The Practice Guidelines describe the best
practices for opticians
 The Bylaws determine how the COO is to
be structured, registration fees, duties and
procedures for council meetings.

Frame Types & Parts read Chapter 1 pg 3 - 9

Frame Types and Parts: Chapter 1
Endpiece nose pad Eyewire or Rim
PLASTIC FRAME

Metal Frame
Metal/Plastic
Combination Frame
Frame Types
Plastic Frame

Semi Rimless/Nylon
Cord Frames
Rimless & Half Eye

Temple types
Skull – are the most popular for plastic frames.
They are bent down slightly over the ear and
follow the contour of the skull.
.

 Library Temple -they
are straight so they
can be slipped off and
on
Convertible – like
library but are designed
to bend down , more
flexible

Comfort Cable - hook behind the ear with a flexible
metal cable and are good for children's glasses and for
sport safety glasses
Riding Bow - are similar to comfort-cables, except the
shaft is more rigid and made of plastic. Only the ends are
pliable

Bridge Designs
Saddle Bridge -spreads the
weight of the glasses evenly over
the sides and crest of the nose
Modified Saddle- nosepads
are built up to distribute the weight
over more area on the nose

Modified Saddle Bridge
nose pads are built up to
distribute the weight over
more area on the nose
Keyhole Bridge
Supports the frame on the
sides of the nose
Does not touch the crest of
the nose

Adjustable nose pads -
the pads alone support
the weight of the glasses
but can be adjusted to
achieve a better fit
Can be mounted on metal
and plastic frames
Comfort bridge - provide
better weight distribution
but cannot be adjusted

Strap Bridge
Is like two adjustable nose pads whose tops are linked together with a
strap.
Commonly used on children's frames
for greater support and comfort

Bridges for Children
 Adjustable Comfort
Bridge – adjusts for optimal fit
and includes a band that fits over
the crest of the bridge
Comfort Bridge

How ophthalmic frames are
made
 https://www.youtube.com/watch?v=Cea4Q
kdWgRg

Frame Measurements and Markings
Read Chapter 2 –System for OD
Using a standard system of measurement reduces the
chance of error when communicating with the lab and
making the eyeglasses.
Since 1962 all frames made by the members of the
Optical Manufacturers Association have been measured
and marked using one system, called the BOXING
SYSTEM of frame measurement
Size stamped on frame - 52 20 – a boxing system
measurement

In the Boxing System, the Datum line is the horizontal midway point on
the lens and used to denote the half way point between the upper and
lower edges of the lenses

“A" Measurement - The horizontal distance between the furthest
temporal and nasal edges of the lens shape or the distance between
the vertical sides of the box. The A measurement is also commonly
known as the eyesize.
"B" Measurement - The vertical distance between the furthest top and
bottom edges of the lens shape or the distance between the
horizontal sides of the box.
Datum Line - The horizontal line that runs through the vertical center of
the frame.

Geometric Center (GC) - The point on the horizontal midline half way
between the two vertical lines that border each side of the lens.
Distance Between Lenses (DBL) - The shortest distance between the
nasal edges of each lens or the distance between boxes. DBL is
also commonly referred to as bridge size.
Geometric Centre Distance - The horizontal distance between the
geometric centers of the lenses. It is more commonly referred to as
the frame PD. In theory the frame PD can be calculated by adding
the "A" Measurement to the DBL as marked on the frame, however
in practice the calculation may differ from the actual measurement.

Measuring the Front
A measurement- from the inside of the temporal to the inside of the nasal side of the
eyewire PLUS ½ mm for the bevel on each side EG 51 + 1mm = 52 mm eyesize
B measurement – from
inside of the top
eyewire to the inside
of the bottom eyewire
PLUS ½ mm for each
bevel
DBL measurement – from the inside of the eyewire on each side at the narrowest point
MINUS ½ mm on each side for the bevel. EG 19 – 1 = 18mm bridge size

Measuring temple length
 From the centre of the screw barrel to the end of the temple
 Measured in millimeters, usually in 5 mm increments
- MIDDLE OF SCREW BARREL
- TEMPLE BEND
TEMPLE TIP

Remember
 The Boxing System is the official frame
measuring system for the industry
 uses a constant reference point for all
measurements - the bevel apex of the
edged lens
 This reduces the chance for error when
making the eyeglasses at the lab
.

Standard Alignment – Read Chapter 8
 Also known as Bench Alignment

Standard Alignment of Frames (Key Points)
The frame must be bench aligned before it
is adjusted on the patient
 Step 1. Begin with the bridge (horizontal
alignment)
- check that one lens isn’t higher than the
other
- check for rotated lens

Step 2. - check that one lens is not more
forward than the other (coplanar
alignment)
- check for skewed bridge (no x-ing)

Check the nose pads
 Tops should be closer
together than the bottoms
 Both should be at the
same height
 Should be about 1mm
from the eyewire
 Back edges should be
farther apart than the
front edges (splay angle)

Step 3 – Check open temple alignment
-check temple shaft is straight
- check open temple angles

Step 4 – Check Temple Parallelism
flat surface touch test check pantoscopic
angle

Step 5 – Check temple bend and endpiece
angle
- Temples should be bent at the same point
- Temple endpieces should be bent equally
inward
- TEMPLE BEND E INWARD
ENDPIECE BEND

Step 6 – Temple fold
- Temples must cross at the centre of the
bridge when folded
- Ensure temple tips don’t rub on the inner
lens surface
- Make sure all screws are tight
- Ensure lenses are clean

Frame Materials read pgs 9 – 14 in text
 Materials used in eyeglass frames are
 plastic, metal, or a combination of the two
(known as composites).
 Manufacturers select materials that are
 cost effective
 adjust easily
 offer safety and workability
 hold the lenses properly
resist breakage, corrosion, and heat.

Plastic Materials
Cellulose Nitrate (zylonite)
 Developed in the 1800’s and was used for making
eyeglass frames.
 Is no longer used
 This material was commonly known as ZYL ( the term is
still used today for plastic frames)
Disadvantages
 Was somewhat unstable.
 Colors faded; material dried and became brittle
 Its chemical make-up was dangerously flammable
 Cellulose nitrate eventually was replaced with a new
material – cellulose acetate.

Cellulose acetate
The most commonly used plastic in eyeglass frames;
made from cotton, wool or pulp and is processed with
plasticizers and stabilizers.
Advantages
 Relatively inexpensive, and easy to work with
 Comes in a wide variety of colors, textures, and patterns
 The material may be worked easily with warm air
 The material will stretch to accommodate a slightly larger lens
 It will shrink to accommodate a lens which is slightly smaller
Disadvantages
 Loses flexibility and colour fades with age – becomes brittle
 The material should be coated to seal the surface
 Can burn if overheated
 Not suitable for very thin frame designs
 Hinges and metal hardware will come loose if overheated

Tips for Handling Cellulose Acetate
1. Do not overheat. The temperature of your warmer should not
exceed +70 degrees Celsius or +160 degrees Fahrenheit
2. Heat only the part of the frame requiring adjustment
 Submerging the entire frame in the heat will undo other adjusted
areas and possibly do permanent damage by loosening hinges
and other secured hardware.

Cellulose Propionate
Another generation of plastic material that allowed manufacturers
to create ultra thin larger frames that were stable
Advantages
 Is light, flexible and retains its shape
 Can be injection molded making it ideal for intricate designs
 Colors are applied in a series of overcoatings rather than being
mixed in with the material itself.
 This offers a good range of colors and the color coating
tends to seal in the plasticizers
 Won’t become dull as quickly as acetate
 Stability of material makes a sturdy, ultra-thin design possible.

Disadvantages
 Propionate is difficult to dye
 Colors may fade a bit more readily and they may exhibit some
inconsistencies in places.
 Can grow dull with age
 Sensitive to solvents
 In addition to acetone, alcohol will attack the surface finish.
 Has low tolerance to excess heat
 Care in handling is a must
 Excessive heat will easily cause the material to bubble or to
otherwise damage the finish
 Repair of these problems is virtually impossible

Tips For Handling Propionate
1. Use an air heater which allows for a more controlled application of
heat.
2.Lenses should be edged to very close to size since it is not well-
suited to stretching or shrinking.
 Attempts to widen or narrow bridges should be done with
caution since the heat normally used to effect these changes will
put the frame finish at risk.
3. Control the location of heat application so as not to overheat parts
which are outside the adjustment area.

Kevlar Developed by DuPont for use in bulletproof
vests . It is mixed with nylon for eyeglass frames. ONLY
USED FOR SAFETY FRAMES
Advantages
 It is strong, pliable and
lightweight
 Good for safety frames
Tips for working with Kevlar
 Make sure the frame fit is
exact before ordering
 Eye and bridge size exact
 Temple length exact
Disadvantages
 Won’t shrink or stretch
 Lenses should be cut on size
for easy insertion
 Adjustments are difficult to
achieve and are prone to
relaxing.
 Limited color and style range.
 Alterations to bridge and shape
configuration are extremely
difficult

Optyl
 An epoxy resin material drawn into the frame
moulds by a vacuum process
 It is thermoplastic- it bends when heated and will
return to its original shape when reheated
Advantages
30% lighter in weight than cellulose acetate a
 hypoallergenic, an advantage to skin-
sensitive patients.
Excellent shape and adjustment retention.
Heat resistant
Available in a wide range of colours

Disadvantages
 Adjustments are a bit more
difficult
 reheating areas will cause
them to return to their
original state.
 Generally more heat is
required to work with Optyl
 Underheating may result in
frame breakage.
Tips for Handling
Optyl
1. Heat the frame well
2. Hold the desired
configuration of the area
being adjusted till the
material cools
3. Temples that are too short
can be pulled to the desired
length- hold till cool
4. Bridges can be adjusted by
warming and stretching or
compressing the material-
hold till cool

An overheated optyl frame will return to its
original shape when reheated

Nylon
 A thermoplastic which can be injection molded
Advantages
 Hypoallergenic, lightweight, resistant to solvents
 Very strong; used for safety glasses
Disadvantages
 Difficult to adjust
 Manufactured only in darker colors
 It can become brittle over time- dries out
 It doesn’t stretch much when heated
 The frame must fit perfectly/cannot be adjusted very much
Tips for handling Nylon
 Make adjustments with high heat and while still hot, submerge
the newly adjusted part into very cold water. This procedure will
stabilize your adjustments.

Polyamide – a blend of different nylon
materials
 Made by injection casting
 Unlike many of the common frame materials
which stretch when heated, polyamide actually
SHRINKS when overheated
 Using the traditional method of “heat and snap”
will often lead shrinking the frame and creating
the illusion that the lenses were ground too large
 Sizing is critical and cold insertion is the
recommended procedure.

Polyamide (a nylon based material)
 Strong, lightweight and can be made thin
 Can be made opaque or translucent
 Resistant to chemicals and solvents and is
hypoallergenic
 Lenses should be edged to size and be
snapped into the frames cold as the
material will not stretch
 It’s best to use a hot air warmer when
adjusting the temples

Advantages
 Hypoallergenic – no
plasticizers used
 Good comfort, lightweight
 Holds its shape
 Resists solvent, oils, cosmetics
 Strength allows for the creation
of ultra-thin designs
 Overall strength superior to
acetate and propionate.
 Available in a full range of solid
and crystalline colors.
Disadvantages
 Limited ability to stretch
 Oversized lenses cannot
be inserted
 Will not go in cold and
heating the frame shrinks it,
making the large lens
problem worse.
 The materials is very
sensitive to overheating
 In addition to shrinking,
aberrations develop in the
material when too much
heat is applied.

Carbon Fiber
 Made from a mix of carbon and nylon
 Is lightweight and strong, but cannot be adjusted
 Can be used for frame fronts but not for temples
 Can be made thinner
 Since carbon is black
 Coloring is achieved through a baked-on enameling process.
 This procedure results in solid or mottled dark colors.
 Lenses should be cut on size and inserted into the frame
without heating “COLD SNAP”

Advantages
 Lightweight
 Durable
Disadvantages
 Impervious to heat
 Cannot adjust to fit
 Only available in dark colours
 Solvents will damage the material
Tips for handling Carbon Frames
1. Frames with eyewire screws should be worked cold like a metal
frame.
2. Frames without eyewire screws should be sized exactly and “cold
snap” inserted. If that is impossible, warm the frame to add a bit of
pliability, then insert.

Polycarbonate
 Primarily used to make lenses, but can also be used for
frame
 Used for sports frames or for safety frames
 In non Rx frames, the polycarbonate frames and lenses
are molded as one unit.
 The material is very impact resistant, but doesn’t adjust
well for Rx glasses
Advantages
 It is as close to UNBREAKABLE as any material can get.
 Its light weight is quite good for delivering wearing
comfort

Disadvantages
 Difficult to work with – not flexible
 The material is soft (this is the source of its strength) but
the surface of the frame is easily scratched
 Vulnerable to a variety of solvents, such as acetone.
 Like nylon and carbon, if the frame does not fit upon
selection there is very little that may be done to improve
on it.
Tips for Handling Polycarbonate
1.Since the material does not stretch or shrink, sizing again
must be exact
2. Like nylon, adjustments will be maximized by
immediately cooling the altered area.

Summary- Plastic Frames
 Many current frames are blends of many
materials
 Many have a low tolerance to heat
 The material is not marked on the frame
 Inspect the frame before heating
 Always start with the lowest heat possible
to avoid damaging the frame

Ophthalmic Frames
Metal Frame Materials

Gold Plating
 made of another type of metal and the surface is plated
with gold (electroplated)
 have no minimum requirements for the total amount of
gold used
 the plating can wear off quickly
Gold Plated Titanium Vintage 14K Gold

Nickel-Based Materials
Nickel is widely used for metal eyeglass frames
Advantage: it is strong and malleable
Disadvantages: people can have allergic reactions to it
(10% of the population is allergic to nickel)
 High quality nickel frames are coated to prevent allergic reaction
Pure Nickel frames resist corrosion and are easily adjusted.
They can be easily coloured.
Nickel Silvers contain more than 50% copper, 25% nickel
and the rest is zinc. It contains no silver.
Monel resists corrosion, is pliable and can be highly
polished. It is made from nickel, copper, iron and traces
of other elements. It is used quite often in frames.

Aluminum
 Is both strong and lightweight and can be finished in a wide range of
colours
 It cannot be soldered so parts must be assembled using screws or
rivets
 Holds adjustments well
Stainless Steel
 Is made from iron and chrome and is highly corrosion resistant
 Is strong and can be made very thin
 It is non allergenic
Titanium
 Is extremely lightweight, strong, corrosion resistant and is
hypoallergenic.
 Can be made very thin
 Cannot be soldered and is more expensive

Bronze
 An alloy made from copper and tin
 Is corrosion resistant
 Is lightweight and colours well
Magnesium
 Can be used on its own or be used as part of an alloy in
combination with other metals
 Is very light and is durable
 Is corrosive – must have a covering to seal it.
Many types of metals are combined to make
hypoallergenic frames that are lightweight, flexible and
durable.

Allergic Reactions
For people who have a history of skin
reactions to frames you may consider:
 Optyl or polyamide frames
 Titanium or stainless steel frames
Contact Dermatitis

Who invented eyeglasses?
 The matter is still under debate
 Hieroglyphics from the 8th century BC depict
simple glass lenses
 The earliest written records on glass
magnification date back to the 1st century A.D.
attributed to Seneca, the Roman philosopher
 The earliest evidence of a convex lens was
described in the Book of Optics, published in
1020 written by the Greek mathematician
Ptolemey

The first eyeglasses in the 15th century
were heavy and held before the eyes with
the hands

Early frame designs
 Pince-nez (1580)
 Scissor glasses were
held before the eyes

No temples!
 French Emperor Scissor
Glasses
 The monocle was considered
a fine article of men’s apparel
in the nineteenth century

Lorgnettes
 Had a handle to hold them
in place
 Were considered jewelry
 Popular in the 1900’s

In 1727, Edward Scarlett an optician
invented the first eyeglasses with a temple
 Frames were made of metal, steel, silver
or gold

A brief history of lenses
 The 1st lenses were plus
power, convex reading
stones made of polished
quarts used for near
vision
 The original simple
magnifiers
 15th and 16th century:
minus lenses were
introduced. Glass
concave lenses that could
correct distance vision.

18th century:
Benjamin Franklin
invented bifocals by
cutting his distance
lenses and near
lenses in half and
mounting them
together. This
allowed him to have
both near and
distance vision
without changing his
glasses.

 I9th century:
cylindrical lenses
were introduced
allowing for the
correction of
astigmatism

 20th century:
advanced lens
technology introduced
hi index, plastic,
polycarbonate lens
materials.
 Refractive surgery
introduced
 21st century, high
definition vision: free
form lens technology,
digital surfacing

For next class
 Read all posted materials
 Read all textbook chapters referenced in
the presentations
 Prepare for weekly quizzes

Opt202 lecture 1 2019

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