Final Exam Flashcards
1
Q
Endpieces
A
Where the temples attach to the frame
2
Q
Hinge barrels
A
3, 5, 7
3
Q
Guard arms/ pad arms
A
Attach nose pads to the frame
4
Q
Butt portion/butt end
A
Temple that is nearest attachment to the front
5
Q
Shank/shaft
A
Area between butt portion/end and bend
6
Q
Earpiece, bent-down portion, curl
A
Temple that bends behind the ear
7
Q
Bend
A
The area on the temple that first touches the ear
8
Q
Mountings
A
Frames without an eye wire going completely around the lens
9
Q
Plastic Frames
A
zyl, cellulose nitrate, acetate.
10
Q
Metal Frames
A
Titanium is most ideal due to low weight
11
Q
Nylon Cord Frames
A
Hold lenses in place by nylon cord. Have rimless appearance.
12
Q
Half Eyes
A
Only for reading correction.
13
Q
Rimless Mountings
A
Hold lenses in place by some other method other than nylon or eye wires.
14
Q
Semiremless mountings
A
Similar to rem less but have a metal reinforcing arm that follows the upper posterior surface of the lens and joins the centerpiece of the frame to the endpiece. (looks like nylon cord)
15
Q
Numont Mountings
A
Hold lenses only in place at nasal edge. Very rare. Have a top area that is attached nasal and then the temples are attached to this same piece.
16
Q
Balgrip mountings
A
Clips hold the lens in place by a notch. Can use different lenses with the same frame as easy to remove.
17
Q
Saddle bridge
A
plastic bridge shaped like a saddle. Weight is even.
18
Q
Modified Saddle
A
Like a saddle bridge butt has nose pads.
19
Q
Keyhole bridge
A
Used with plastic frames
20
Q
Pad bridge
A
Used with metal frames. Nose pads are attached to support the weight of the frame alone.
21
Q
Comfort bridge
A
When a metal frame has a clear plastic saddle-type bridge.
22
Q
Butt type endpiece
A
Front is straight and butt is flat and meet at 90 degree angle
23
Q
Mitre type endpience
A
Front and butt meet at 45 angle
24
Q
Turn back endpeince
A
Frame front bends around and meets the temple end to end.
25
Skull temples
Bend down behind the ear and follow the contour of the skull.
26
Library Temples
Pratically straight and hold by pressure against the head
27
Convertible temples
Can go between skull and library.
28
Riding bow temples
Go all the way around the ear. Common with kids
29
Comfort cable temples
Same as riding bow temples but are metal with a curl.
30
Strap
Made of a shoe and ear. This is what touches the lens.
31
Shoe
Contacts edge of the lens and braces it from rocking.
32
Ear
Extends fro shoe and touches lens.
33
Arm
Part of semi rimless mounting that extends along the top edge of the frame.
34
Vertical gradient
Darker at the top
35
Horizontal gradient
Darker at temporal portion
36
Clear bridge
Similar to horizontal gradient and is dark at the top except the bridge.
37
Optyl
Thermoelastic (will return to normal shape when heated) Has a plastic memory.
38
Polycarbonate
Used for safety. Clear.
39
Carbon graphite
Very opaque and strong. Brittle in the cold.
40
Nickel Silvers
No silver. Copper, Nickel, zinc.
41
Titanium
Most popular metal.
42
Geometrical Center
Where horizontal and vertical line meets.
43
Eye size
Horizontal length (A) of frame.
44
Lens size
Horizontal length (A) of lens.
45
Effective diameter
Twice the geometric center.
46
Frame difference
Difference between A and B measurement. Greater value is more rectangular.
47
DBL/bridge size
Distance between two boxes.
48
GCD
Distance between two geometrical centers. Can also find by adding A+DBL. Also called frame PD.
49
Frame Markings
Most frames are marked with eye size (A), DBL, and temple length.
50
Z87/Z87-2
Frames that have passed ANSI standards for safety glasses.
51
To lengthen the nose
Pick a frame that exposes the most of the nose to lengthen it.
52
Frontal angle
Chicken dance
53
Splay angle
beauty queen wave.
54
Crest angle
Airplane.
55
Frames for progressive wearers
Require minimal vertex distance, adequate pantoscopic tilt, sufficient vertical depth.
56
Polycarbonate
1.586.
57
Cr 39
1.498
58
Glass
1.523
59
High plus frame differences
Don't use greater than 9 mm.
60
Lenses for kids
Polycarbonate or trivex
61
Where to start with standard alignment?
The start
62
Method of choice for heating frames?
Forced hot air
63
Standard Alignment
Horizontal, vertical, temple parallelism, open temple spread, temple ends, temple fold angle
64
Vertical alignment
Test with four point test. A ruler across the back will touch all four surface. May not confirm if they have too much face form.
65
Open temple spread
No more than 95.
66
Temple parallelism
Should not tip when you hit glasses when laying flat. Varies by pantoscopic tilt.
67
Pantoscopic tilt
Can be between 4-18 degrees.
68
Temple bend
Should be bent down equally and slightly inward.
69
Frontal angle
Should be about 20 degrees from vertical.
70
lens material for rimless
Trivex and polycarbonate
71
Triangle of Force
Crest of the nose and the endpoints.
72
Perfect temple spread
Should have no pressure until just above the root of the ears
73
Temples not spread far enough
The frame will have too much pressure and will bow out. The frames will go forward. They will put pressure on the back of the ears
74
Temples spread too far
The frame will slip down.
75
What pressure would be exerted if temple spread angle is too little on right side?
There will be pressure on right nose (glasses will be further out) and on left side of nose.
76
To move one lens closer to the face
If left lens is IN-->bring left temple in
| If right lens is OUT-->Bring right temple OUT.
77
To move one lens higher on the face
If left lens is up-->Bend left temple up
| If right lens is down-->Bend right lens down
78
Temple adjustments
Should increase friction (touch)
79
Temple bend
Ideal just past the top of the ear.
80
Cable temple adjustment
The very end should be bent backwards to stop from digging into the head.
81
Adjust _____ before adjusting pad angles
Panto tilt
82
When are nose pads adjusted correctly?
1. The pads should rest halfway between the crest of the nose and the inner corner of the eye
2. The long diameter of the pads should be perp to floor when head is erect
3. The full surface of the pads should rest uniformly on the nose
83
When glasses still slip when properly aligned?
Replace nose pads for silicone ones.
84
Frame to the right
Move pads to the right. And vice.
85
To move frame higher on the face
Shrink or narrow the bridge, add pads to plastic bridge, narrow distance between pads, lower vertical position of pads.
86
To move frame lower on the face
Stretch or widen the bridge, spread adjustable pads apart, raise vertical position of adjustable pads.
87
Crown Glass
1.523 High weight and impact resistance.
88
CR-39
1.498
89
Poly
1.586
90
Trivex
1.532
91
When can you provide non-impact resistance?
When a physician or optometrist determines that impact resistance will not fulfill the patients visual requirements.
92
Dress lenses minimal thickness?
No minimal thickness but must be able to withstand impact.
93
Batch testing
Test a group of certain minimal thickness.
94
Records with purchased eyeglasses
Must be kept for 3 years.
95
Basic Safety glasses minimal thickness
3 mm except for +3 or higher (2.5 mm)
96
High Impact safety glasses
2 mm
97
Hardening of Glass Lenses
Temperaturing or chemically tempering. Will see a Maltese-cross pattern with colmascope. Drilled lenses that are heat treated are not safe.
98
Horizontal placement of lenses
Normally make it so OC will line up with the pupil of the eyes. There will be no prismatic effect.
99
Major reference point
Where the prismatic effect equals the prescribed prism
100
When does OC=MRP
When there is not any prescribed prism
101
MRP vertical displacement
Unless otherwise specified will be halfway between top and bottom of frame.
102
Amt. of pant required with different OC placements
Eyes above OC->pant
| Eyes below OC->retro (not done). Each mm=2 degrees
103
Determining MRP height
Measure pupil center height. Compensate pant tilt. 2 for 1 rule.
104
Average vertex distance
14mm
105
Distometer
Used to measure vertex distance
106
Progressive Height
Center of pupil for reference
107
Bifocal Height
From lower lid
108
Trifocal Height
Lower edge of the pupil
109
Double D
Top will be 13-14 mm above lower seg. position. Must get a frame that allows 9 mm for upper segment.
110
Seg height difference
Will need prism. 1 D for each .3 mm difference. Seg line should be moved in direction the prism apex points.
111
Round segs
Must be 1 mm higher than flat tops.
112
Segs seems too high
Increase Panto tilt, decrease vertex distance, spread pads (lower frame), stretch bridge, move pads up.
113
Segs seems too low
Narrow pads, bend pads down by adjusting pad arms, increase vertex distance, reduce pant. tilt, shrink bridge.
114
Correcting set height with incorrect eye size
The set height is correct by one half the difference between same frame eye size and desired eye size
115
Base Curve
The beginning curve on which the lens power is based
116
Spherical lenses
The front curve is the base curve
117
Minus spherocylindrical
Front spherical curve is the base curve. The weaker back surface is the toric base curve.
118
Multifocal lens base curve
The base curve is always on the same side of the lens as the segment
119
If decent ration occurs along axis meridian
No prismatic effect will occur
120
Chromatic abberation
Color related
121
Monochromatic aberration
Occurs with only one wavelength
122
Longitudinal chromatic abberation
Diff. colors bend at different rates
123
High abbe number
Low CA
124
Lateral CA
Diff. in mag differences or prismatic effects.
125
Seidel Abberation
Monochromatic abberations. Spherical abberation, coma, oblique, curvature of field, or distortion.
126
Spherical aberration
Paralax and axial rays focus at different places
127
Coma
Image appears as a coma for off center
128
Oblique astigmatism
Get line images
129
Tilting effects
Creates oblique astigmatism
130
Pincushion
Occurs with plus lenses
131
Barrel distortion
Occurs with minus lenses
132
Fitting cross
Should be placed exactly in front of the wearer's pupil center
133
PRP=
MRP
134
Adjust frame for progressives
Small vertex distance, maximum pant tilt, fitting cross in front of eyes.
135
Greatest problem with PALs
Unwanted cylinder.
136
Hard design PALS
Change in power is sharp
137
Soft design PALS
Change in power is gradual
138
Near Variable
When intermediate and near vision are the primary viewing needs.
139
Uniform transmission
Applies to a 2 mm thick plano lens
140
Most harmful rays
UV C
141
How much tint
want transmission to be 15-30%
142
Inserting lens
From the front
