6 - Troubleshooting Frame Adjustments & Repairs Flashcards
What are the 3 points of the fitting triangle?
The roots of each ear
Nose
What happens when the temples aren’t spread enough? 2
Pressure on the side of the head
Frame will fall forward on the nose
What will a px say if the temples aren’t spread enough? 2
Slide down their nose
Hurt behind their ears
What causes the temples to spread too much? 3
Older frame stretches over time
Sleeping in glasses
Wearing them on their head
What will a px say if the temples are spread too much? 2
Falling off
suddenly too big
What is the solution to inequality in vertex distance? Left + Right 4
If left lens is IN = bring left temple IN
If right lens is OUT = bring right temple OUT
If right lens is IN = bring right temple IN
If left lens is OUT = bring left temple OUT
What will a px feel if their in inequality in the vertex distance?
The side the temple is not spread enough will cause a sore ear and the opposite side of the nose will hurt.
Clothes pin effect by pinching the face
What will a px say when the frames touch their cheeks? 2
Lenses are dirty (because they are touching the face)
Touching my face
How can we stop/avoid glasses touching the checks? 3
Get px to smile when choosing to see if it will be a problem
Plastic frame - use stick on pads
Metal frame - nosepads can be at the same angle but moved lower which raises the frame
What can cause glasses to be lop-sided? 2
Sat on them
Stepped on them
What should be checked if the frames are lop-sided? 4
Hinge is not broke/loose
Skewing at the bridge
See if their is a gap between the temple butt end and the frame front
Temple bend
What is the solution when the lenses are different heights? Right + left 4
If left lens is UP = bend left temple UP
If left lens is DOWN = bend left temple DOWN
If right lens is UP = bend right lens UP
If right lens is DOWN = bend right temple DOWN
If the temple bend is a problem affecting the height of the lenses what should you do/
Check to see which bend occurs too short of the root of the ear
heat it and straighten
Rebend in a more appropriate place
What happens to a px’s vision when the glasses sit too high or too low? 4
No longer looking through Optical centre, this will induce unwanted prism - double vision / objects appear taller or shorter.
What is the relationship between the nosepads and the height of the lenses?
Widen the nosepads = lowers glasses
Narrow the nosepads = heightens glasses
What 3 adjustments can be done to move the frame away from the face/eyes?
1.Narrow nosepads (also raises frame).
2.Increase effective length of pad arms.
3.Decrease face form (make frame front straighter).
What 3 adjustments can be done to move the frame closer to the face/eyes?
1.Spread nospads apart (also lowers frame).
2.Decrease effective length of pad arms.
3.Increase face form (make front more curved).
What 3 adjustments can we do to move the frame off the cheeks?
1.Decrease pantoscopic tilt.
2.Raise the frame by narrowing the distance between pads
3.Increase vertex distance by narrowing distance between pads or extending the effective length of the pad arms.
What 3 adjustments can we do to move the frame off the brows?
1.Increase pantoscopic tilt.
2.Lower the frame by widening the distance between pads.
3.Increase vertex distance by extending pad arm effective length - this may raise the glasses
What 3 adjustments can be done to move the frame higher on the face?
1.Narrow the distance between adjustable pads.
2.Lower the vertical position of adjustable pads.
3.Add pads to plastic bridge
What 2 adjustments can be done to move the frame lower on the face?
1.Increase the distance between adjustable pads.
2.Raise the vertical position of adjustable pads.
What is pantoscopic tilt?
pantoscopic tilt is the amount the frame front is tilted with reference to the plane of the face
What is the rule when measuring OC’s in regard to pantoscopic tilt? 2
A correctly fit pair of glasses will drop the optical center 1mm for every 2 degrees of pantoscopic tilt
Should never be lowered to be under datum line
What kind of tilt is needed in these conditions:
Eyes at OC =
Eyes above OC =
Eyes below OC =
= No Pantoscopic tilt
= Pantoscopic tilt required
= Retroscopic tilt needed (not done in practice/new frame choice)
As a general rule, eyeglasses need to be adjusted so that the lower rims of the frame are closer to the face. This widens the viewing area for the wearer and is more cosmetically appealing. T/F
True
If the bifocal segment is too high what should you do to the tilt?
Increase the pantoscopic tilt
If the oc height is too low how do you adjust the panto tilt to help ?
decrease the pantoscopic tilt (not practical)
What should we look at when we check fit? 3
Width
Nose
Temple
What are 3 fitting considerations when fitting a progressive/bifocal?
A minimal vertex distance.
An adequate pantoscopic tilt.
Sufficient vertical depth in the nasal portion of the frame shape.
What are the 3 types of nosepads?
Silicone
Acetate
Vinyl
Characteristics of silicone nosepads? 3
Grippy
Pulling sensation on nose
dont slide compared to others
Characteristics of vinyl nosepads? 3
Soft
Flexible
Not as grippy frames may slip
Characteristics of acetate nosepads? 2
Hard Material
Does not flex
