Integrated Optics III

The basic parts of a frame are

• the frame front

• the temples

when connected by a solid bridge of any kind (metal or plastic), the frame front is the combination of

eyewires, bridge, and endpieces

the eyewire is

the rim of the frame that goes around the lenses.

the bridge is

the part between the two eyewires

What type of bridge is this?

(Plastic) Saddle Bridge - the weight is evenly distributed over the sides and crest of the nose

What type of bridge is this?

(Plastic) Modified Saddle Bridge - nose pads are added to help carry some of the weight of the frame

What time of bridge is this?

(Plastic) Keyhole Bridge - the bridge rests on the sides of the nose and not the crest of the nose

What type of bridge is this?

(Metal) Nose Pad Bridge - the pads support the weight of the glasses

What type of bridge is this?

(Metal) Comfort Bridge - clear plastic saddle added with screws or snapped into a metal frame

What type of bridge is this?

Metal Saddle Bridge - no nose pads or comfort bridge; can cause irritation

Nose pads are designed to

contact the nose, hold the frame up off the nose, and away from the face. they support the eright of the glasses.

Guard arms are

the small wire arm that holds the nose pad in place.

The endpiece is

one of the two outer areas of the frame front to the extreme left and right where the temples attach to the frame front

Hinges:

part where the temple is connected to the frame front, and allows the temple to fold in and out to the frame front and usually hed in place by a screw

Spring Hinge:

allow frames to stay in adjustment for a longer period of time

prevents stress on the temple that comes from constantly taking off glasses

they can freeze, break, and add weight to the frame

they don’t improve the fit

Temples:

the pieces that hold the frame front to the head and ears

run from the endpiece on the frame front back to behind the ear

What Temple style is this?

Skull - the most common temple style

bends down behind the ear and follows the contour of the skull

the bent-down portion is narrower at the top of the ear and widens towards the end

What temple style is this?

Riding Bow temple - plastic material

similar to comfort cable, seen on children’s frames

What Temple style is this?

Library - straight back

hold glasses on by pressure against the side of the head

originally popular for reading glasses

some sports glasses use this (it fits under helmet)

What Temple style is this?

Convertible Temple - versatile: can switch between skull and library

What Temple style is this?

Comfort Cable - metal material

wrap around the entire ear to hold glasses firmly in place

found on some safety glasses and shooting glasses

Temple Tips:

usually, removable plastic sleeves that slip over the ends of the metal temples to provide comfort for the wearer

the part of the temple on a plastic frame that goes behind the ear

Full Frame (Metal):

the metal frame has a solid metal eyewire that surrounds the entire lens

Full Frame (Plastic):

characterized by a plastic eyewire around the entire lens

Bevel:

how the lenses are held in place in most full frames

Cold Insert:

no heat to insert lenses

Semi-Rimless:

semi-rimless mounting/ groove mount/ logo

half an eyewire of metal or plastic with attached nylon fishing cord

can also be drill mounted

Combination Frame:

metal chassis and plastic top rims or frames with some major parts plastic and some of metal

3-Piece, Rimless, Drill Mount:

created by attaching two temples independently, then attaching a bridge directly to the lenses through holes that have been drilled through them

only polycarbonate or higher index lenses MUST be used (CR-39 or mid-index lenses will crack/break)

modern mountings are assembled using plastic sleeves and pressure fittings instead of screws.

Numont (Antique Design)

one point of attachment per lens (nasal edge)

Balgrip (Antique Design)

notches in lenses; held by clips

Universal Fit (Asian Fit)

helps with individuals who have flatter/lower nosebridges

higher nosepad height for better fit

flared nose pad design for improved stability

narrower distance between lenses for added comfort for a narrower bridge

less frame front curvature easier to fit a wider range of faces

Occipital Wrap:

highly extended endpiece, seen on sports eyewear and others

Plastic Frame Materials: Zyl

Cellulose Acetate (“zyl”) makes up the majority of plastic frames on the market

What are the advantages of Zyl?

light in weight

huge range of colors/patterns

string

fairly easy to adjust

can be molded in any shape and size

What are the disadvantages of Zyl?

can lose shape and even be ruined by high heat

will discolor over time

will dry out and become brittle over time

will stretch out and lose fit in hot weather

Plastic Frame Material: Cellulose Nitrate

“zylonite”; flammable

Plastic Frame Material: Propionate

lighter weight than zyl; inexpensive but color can fade easily

manufactured by injection molding

Plastic Frame Material: Optyl

stronger and lighter than zyl

epoxy resin with thermo-elastic (“memory”)

hypoallergenic

manufactured by injection molding

Plastic Frame Material: Nylon/Polyamide

lightweight, flexible, durable, translucent (in color and design)

hypoallergenic, chemical resistant

manufactured by injection molding

Plastic Frame Material: Carbon Fiber

combined with nylon: thin, light, strong

Plastic Frame Material: Polycarbonate

sports, safety purposes

Plastic Frame Material: Kevlar

combined with nylon: strong and lightweight

Plastic Frame Material: Rubber

sports eyewear/ sunglass frames/ swim goggles

What Plastic Frame Materials are NOT adjustable?

carbon fiber, polycarbonate, kevlar, rubber

Metal Frame Material: Monel

nickel-based metal with copper and iron: ~65% nickel

makes up the majority of all low and mid-range metal frames made today

What are the advantages of Monel?

easy to adjust

holds adjustments well

very strong

relatively light in weight

can have a wide range of colors and plating

economical

can be repaired with solder

What are the disadvantages of Monel?

outermost plating can wear off resulting in skin allergies or reaction to nickel

prone to breaking after repeated bending

once plating is worn away, metal may erode quickly and create abrasive areas and sharp edges

the heaviest of metal frame materials

Metal Frame Material: Stainless Steel

used in many mid-range to high-end frames

very thin: may be just a little thicker than a paper clip

most stainless-steel frames are marked on the demo lens and/or inside the temple “Stainless” or “Stainless Steel”

What are the advantages of using Stainless Steel?

light in weight/strong

corrosion resistant

doesn’t contain nickel so less chance of allergic reactions (not truly hypoallergenic material)

holds color well

attractive appearance

springiness/flexibility

What are the disadvantages of using Stainless Steel?

limited range of colors

colors tend to have a matte finish

larger frames can become heavy

temples are rarely made in any other shape other than “paper clip”; very thin temple

Metal Frame Material: Titanium

used in many mid-range to high-end frames

versatile and abundant

Vision Council of America est voluntary marking guidlines for frames containing titanium

• certified 100% titanium: at least 90% of frame is titanium with no nickel

• certified “beta titanium”: at least 70% titanium and no nickel

What are the advantages of using Titanium?

hypo-allergenic: lacks nickel material

extremely lightweight (almost ½ weight of other metals)

100% corrosion, rust, and tarnish proof (will last long time)

extremely durable - can last for years

very strong so frames can be made thin and hold their shape, so fewer adjustments needed

What are the disadvantages of using Titanium?

not as easy to manufacture so it’s more expensive

special soldering (brazing) required

adjustments can can tricky - if not made well, it can break easily at solder points

discourages repeat sales due to its durability

Metal Frame Material: Memory Metals (mix of titanium and other metals)

generally high-end

popular for kids frames - they bend, not break

not all are created equal

difficult to adjust

not hypoallergenic

Metal Frame Material: Aluminium

strong, lightweight, no flexibility

wide variety of colors, no corrosion

Sustainable Materials:

historic airplane material

vinyl from recods

buffalo horn

skateboards

private jet interiors

wood

• lightweight

• reclaimed

• unique

• biodegradable

Sustainable materials are virtually impossible

to adjust

What are hypoallergenic choices for material allergies?

optyl**

polyamide

titanium**

stainless steel

What is the first thing to do when doing bench adjustment?

tighten the screws: tight scres create resistance - this is needed to bend a frame properly

What are some Bench adjustment tools?

frame warmer

salt pan

optical screwdriver

wise jaw angling pliers

flat round nylon jaw pliers

case angle pliers

needle nose pliers

european nose pad pliers

use heat when adjusting

plastic

do NOT use heat when adjusting

metal

What is the single most important factor in determining proper heat setting?

the thinness of the frame material

the enemy of all frame materials is

excessive heat

after using the frame warmer, the frame is ready when it

is pliable. don’t wait until it actually softens

What are tips to remember when using the frame warmer?

heat only the part of the frame that you’re working on

make sure the material can handle the heat

be mindful of lenses with A/R coating

use it to insert (mount) lenses or remove lenses

Where should you start when doing Bench adjustment?

always start at the bridge, work your way towards the endpieces and then the temples

Alignment of Frame Front:

is all about the bridge! there is both a horizontal and vertical alignment component

Horizontal Alignment of Frame Front:

skewing: a bridge misalignment when one lens appears higher than the other.

How to correct skewing:

heat the bridge and force one side up and the other side down.

How do your check Vertical alignment:

four-point touch

What is face form/wrap around?

when the frame front is slightly rounded to the form of the face

the bridge sits slightly more forward than the end pieces

What purpose does face form/wrap around serve?

cosmetic purpose: improving frame appearance

optical purpose: aligning the lens with the patient’s line of sight

What is X-ing (or propeller)?

the frame front is twisted forming an “x” when viewed from the side

How do you correct x-ing?

heat the bridge and bend in opposite directions (like wringing out a cloth)

What is the variant plane assess?

the lenses are parallel - one lens may be further forward than the other

Angles formed between the temple and frame front should be

between ~90-95 degrees and equal on both sides

Temple Parallelism: the two temples must be

parallel to one another when viewed from the side

What is used to check for temple parallelism?

the flat surface touch test or ‘wobble test’

The ‘wobble test’ helps to assess

if pantoscopic tilt is even on both sides

What is pantoscopic tilt?

the angle between the plane of the frame front and a plane perpendicular to the temple when viewing frames from the side

the amount of inward tilt of the frame front, away from the vertical

frames should have slight pantoscopic tilt, ~10-12 degrees

How do you adjust pantoscopic tilt on frames?

use a wide jaw angling plier to increase/decrease panto tilt at the hinge

What is the proper bench adjustment for skull temples?

1 ½" from end of temple

bent down equally, about 45 degrees

turned inward slightly, about 5 degrees

*should be heated first! in a metal frame, heat the plastic portion only

Temple Fold Angle:

also called Case Angle; it is the temples in closed position

What do you use to adjust the Case Angle?

case angle pliers

When do you not use heat to adjust plastic frames?

when changing pantoscopic tilt. do NOT heat the hinge of the frame

What is the EXCEPTION to heating metal frames?

when bending end of temple with a plastic covering

otherwise, DO NOT heat metal frames

Adjusting nosepads can

adjust frame height

adjust vertex distance

move the frame left/right

Guard Arm types:

“domestic”: question-mark style

“european”: inverted U-shaped

What are the different types of nose pads adjustments?

frontal angle

splay angle

vertical angle

pad spacing/pad height

Pad Adjustment: Frontal Angle

the vertical position of pads when viewed from the front

chicken flapping its wings

Pad Adjustment: Splay Angle

the angle created by the face of pad when viewed from above

beauty pageant wave

Pad Adjustment: Vertical Angle

the angle the longitudinal axis of the nosepad make when viewed from the side

flight attendant wave

Pad Adjustment: Pad Space and Pad Height

pushing the entire guard arm closer or further away from each other

pads should be:

1. equidistant from eyewire

2. about 1mm closer to nose than eyewire

3. at the same height - occupying the same horizontal plane

Overview of Adjusting the Frame on the Patient:

temple spread

equality of vertex distance

pantoscopic tilt

level of eyewires

temple fit

Frame Fitting Theory: Fitting Triangle

the temples should leave the frame front and go straight back and only touch the face where the temples meet the ears

frame should fit like a triangle: points of contact at crest of nose and tops of ears

A frame with some face form maximizes

a close fit for optimum vision

neutral or negative face form allows light to reflect off the back surface of the lens

What is the first component to consider in frame selection?

width - most important factor in the fit of a frame, some frames come is several eyesizes

Temples should NOT

put pressure on the sides of head