Exam 1 Homework Questions

True

T/F: When distance and add powers are both low, there will be little difference between add powers found using front and back vertex powers. For this reason, might be easier to measure adds with back vertex powers instead of turning the glasses around.

True

T/F: When nylon is used alone in spectacle frames it will lose its flexibility unless periodically soaked in water overnight.

False

T/F: When there is prescribed prism present, the OC and MRP are one-and-the-same.

True

T/F: When using paper prescription forms it is very important to print the necessary information. Poor or illegible handwriting usually results in errors.

False

T or F: Optyl is a thermo elastic material, thus it will bend down when heated but will not return to its original shape when reheated

True

T or F: Polyamide frames can be made opaque or translucent

True

T or F: Polycarbonate frames are better suited for sport/safety eyeglasses rather than conventional eyeglasses

False

T or F: Propionate has more color stability than cellulose acetate, thus it will not fade quickly

False

T or F: Two frames having the same DBL will fit the same person in the same manner even with different lens shapes

True

T or F: When the illuminated target shows both sphere and cylinder lines that are both clear at the same time, the lens is a sphere.

False Right lens first

T or F: When writing a spectacle prescription in paragraph form, such as in a letter, always write data referring to the left lens first, followed by the data for the right lens

False

T/F: After the first lens is spotted in the lensometer, you move the second lens and notice the target is not centered in the reticule. The next step is to MOVE the instrument table up or down to center the target. Proceed to spot the lens, then measure the distance between OC's and move on.

True

T/F: After the first lens is spotted in the lensometer, you move the second lens and notice the target is not centered in the reticule. The next step is to record the amount of resulting vertical prism seen in the instrument. Spot the lens once. Now move the instrument table up or down until the target is centered vertically. Proceed to spot the lens a second time, then measure the distances between OCs and move on.

False

T/F: All lensmeters are manual.

True

T/F: If a carbon fiber frame does not fit well when a patient tries it on during frame selection, you will not be able to fit it better later on

True

T/F: Metal frames made out of nickel resists corrosion.

True

T/F: The ED measurement helps determine the smallest lens blank from which the lens can be cut.

False It is the parallel line drawn halfway between horizontal lines at top and bottom of the lens

T/F: The datum line is a line drawn halfway between the two vertical lines and parallel to them in the older datum system.

sphere lines

The THIN lines in the lensometer target are the _____________. cylinder lines sphere lines

True

T/F: The focusing procedure for a lensometer is only done once and is not needed to be repeated for each pair of spectacles being measured when the lensometer is being used by only you at that moment.

True

T or F: Metal frames made from pure nickel are easily adjusted

1.23

A lens has a distance front vertex power that reads 1.77 −1.68 × 090. The front vertex power through the near addition reads 3 − 0.02 x 090 What is the add power using the spherical lines?

Shaped like an old-fashioned jeyhole.

Define Keyhole bridge

Has fixed nose pads attached at the back to increase the weight-bearing area of the frame.

Define Modified Saddle

Shaped like a saddle that follows the bridge of the nose to allow the weight of the frame to be evenly distributed.

Define Saddle Bridge

Used in metal frames where nose pads are attached to the frame by metal pad arms.

Define pad bridge

A. Is the vertical distance from the lowest part of the lens bevel to the top of the bifocal or trifocal segment line

Define segment height A. Is the vertical distance from the lowest part of the lens bevel to the top of the bifocal or trifocal segment line B. is the front curve of a multifocal lens C. is measured across the widest portion of the segment, not the top of the segment

is measured across the widest portion of the segment—not the top of the segment.

Define: Segment size. is the vertical distance from the lowest part of the lens bevel to the top of the bifocal or trifocal segment line. is measured across the widest portion of the segment—not the top of the segment. is the front curve of a multifocal lens.

The temple and frame front meet at a 90-degree angle

Describe the Butt endpiece construction

The temple and frame-front meet at a 45-degree angle.

Describe the Mitre endpiece construction.

The frame front bends around and meets the temple end to end.

Describe the Turn-back endpiece construction

Flexible metal temples that curve/curl around the ear where it meets the head.

Describe the temple construction of Comfort Cable.

Straight temples that use pressure on the side of the head to hold the glasses on.

Describe the temple construction of Library.

Plastic temples that curve/curl around the ear where it meets the head, extending to the level of the earlobe.

Describe the temple construction of Riding Bow.

The bent down portion follows the contour of and rests evenly against the skull.

Describe the temple construction of Skull.

Can be bent down from striaight-back to skull design

Describe the temple construction of the Convertible.

False Need a coding to not corrode

T or F: Metal frames made out of magnesium are resistant to corrosion

Geometrical center distance (GCD) or frame PD

Identify 5 in the picture

Butt

Identify the endpiece construction ( the two end pieces come together at a 90 degree angle) Turn-back Mitre Butt

Mitre

Identify the following endpiece construction. Butt Turn-back Mitre

C

Identify the following term labelled 6 in the figure below:

Modified saddle bridge

Identify the following type of bridge type Pad bridge Modified saddle bridge Saddle bridge Keyhole bridge

Pad bridge

Identify the following type of bridge type. Keyhole bridge Modified saddle bridge Saddle bridge Pad bridge

Half eyes frame

Identify the following type of frame/mounting Nylon cord frame Half eyes frame Numount mounting Semirimless mounting Plastic frame Rimless mounting Combination frame

Combination frame

Identify the following type of frame/mounting. Combination frame Numont mounting Plastic frame Nylon cord frame Semi-rimless mounting Half-eyes frame Rimless mounting Metal frame

Numont mounting

Identify the following type of frame/mounting. Semirimless mounting Plastic Frame Combination frame Metal frame Half-eyes frame Rimless mounting Nylon cord frame Numont mounting

Bend

Identify the part of the temple that is labeled C. Shaft or shank Earpiece Butt Bend

Passes

If the amount of total horizontal prism less than 0.67∆, but the horizontal difference is less than 2.5 mm, the lens pair ____________. - fails - passes

Passes It needs to fail both criteria for the lens pair to fail

If the amount of vertical prism is less than 0.33∆, but the vertical difference is greater than 1 mm, the lens pair ____________. - fails - passes

16

If you select a frame that is marked with "52-16" or "52/16", which number stands for distance between lenses frame measurement?

Bridge size or DBL

In the boxing system ___________ is measured on the frame as the distance from the inside nasal eyesore grooves across the bridge area at the narrowest point

GCD

In the boxing system ___________ refers to the distance between the two geometric centers of the lenses

B

In the boxing system, _______ is the vertical boxing length.

C

In the boxing system, _________ refers to the lens width along the horizontal midline.

True

T or F: If there is no prescribed prism in the prescription, this horizontal distance between OC's should equal the wearer's PD

30%

Optyl material is about ____% lighter than cellulose acetate.

Incorrect Missing the 0 in front of -0.50 and -0.75

State whether each prescription is written correctly or incorrectly. OD: -.50 -3.00 x 040 OS: -.75 -2.50 x 130

Incorrect No degrees marks

State whether each prescription is written correctly or incorrectly. OD: -7.00 -1.00 x 180° OS: -6.50 -1.50 x 90° Incorrect Correct

Incorrect

State whether each prescription is written correctly or incorrectly. OS: -5.50 -1.00 x 020 OD: +1.75 -1.50 x 110 - Incorrect - Correct

True

T or F: Cellulose acetate does become brittle with age

Endpieces

The outer areas of the frame front, to the extreme left and right where the temples attach, are known as the ____________________. Bridge Endpieces Nose pads Hinges Eyewire Shield

shank or shaft

The portion of the temple between the butt end and the bend is the ______________. butt portion or butt end earpiece or curl bend shank or shaft

butt portion or butt end

The portion of the temple that is nearest its attachment to the front is the __________ shaft or shank earpiece or curl butt portion or butt end bend

90

When verifying a pair of glasses and the cylinder lines begin to clear first, the axis wheel should be rotated _______ degrees, causing the sphere and cylinder lines to transfer places. 60 30 45 90 180

2

When writing a prescription for the sphere and cylinder power components, carry figures _____ places after the decimal point. - 4 - 5 - 2 - 3 - 1 - 6

1. Focus the eyepiece 2. Turn the power wheel into the minus until the illuminated target blurs out 3. Turn the power slowly in the plus direction until the sphere lines are clear 4. Adjust the axis wheel for optimum sphere line clarity. 5. Record the sphere power and cylinder axis 6. Turn the power wheel farther in the plus direction until the cylinder lines clear 7. Take the difference between the two power wheel reading and record as a minus cylinder

What are the steps for measuring a single vision sphere-cylinder lens power using PLUS CYLINDER FORM?

Finished in variety of colors Holds adjustment Does not corrode

What features match the characteristics of metal frames made out of Aluminum (select 3). Only comes in one color Does not hold adjustment well Finished in variety of colors Holds adjustment corrodes easily does not corrode

strong inflexible lightweight

What features match the characteristics of metal frames made out of Aluminum (select 3). strong heavy inflexible flexible lightweight weak

Does corrode if not sealed Lightweight Durable

What features match the characteristics of metal frames made out of Magnesium. (select 3) Heavier material than other material metal frames are made out of Does corrode if not sealed Delicate Lightweight Resistant to corrosion Durable

Lightweight Flexible Strong

What features match the characteristics of metal frames made out of Titanium (select 3). Weaker than other metal frame materials Lightweight Heavier than other metal frame materials Flexible Strong Inflexible

1.50Δ BU & 2.50Δ BO

What is the amount of prism shown in this left lens? 1.50Δ BD & 2.50Δ BI 2.50Δ BU & 1.50Δ BO 3.50Δ BU & 2.50Δ BI 1.50Δ BU & 2.50Δ BO 2.50Δ BU & 3.50Δ BI 3.50Δ BU & 2.50Δ BO 2.50Δ BU & 3.50Δ BO

26

What is the fame difference of the lens? A = 53 B = 27

C

What letter matches to the photo of a convertible temple construction?

D

What letter matches to the photo of a riding bow temple construction?

Lens spotting device

What part of the manual lensometer is labeled C? Prism compensating device Power wheel Axis wheel Lens spotting device Lens holder Eyepiece

Axis wheel

What part of the manual lensometer is labeled E? Prism compensating device Power wheel Axis wheel Lens spotting device Lens holder Eyepiece

nylon

What plastic frame material is described below? Must be periodically soaked in water to keep from becoming brittle and to maintain high flexibility

Polyamide

What plastic frame material is described below? A nylon-based material that is 72% of the weight of cellulose acetate, is resistant to chemicals, and can be made opaque or translucent.

Propionate

What plastic frame material is described below? Frames are produced with injection molding and are 3/4 the weight of cellulose acetate.

Cellulose acetate

What plastic frame material is described below? More often skin problems are not so much allergic reactions to the material itself, but to those things which can be absorbed by the material. Cellulose acetate Optyl Cellulose propionate Nylon Polycarbonate Polymide

Lens clock

What tool is used to check the base curve of a lens? Prism compensating device Lens clock Lens calipers Frame tracer Circumference gauge

Frame tracer

What tool is used to trace the inside bevel of a frame to record its shape? Prism compensating device Lens clock Lens calipers Frame tracer Circumference gauge

Begin with the strongest lens first. For this purpose the strongest lens is defined as the lens with the strongest power in the 90-degree meridian.

When reading a spectacle lens prescription, which lens should be verified first? Begin with the strongest lens first. For this purpose the strongest lens is defined as the lens with the strongest power in the 90-degree meridian. Begin with the strongest lens first. For this purpose the strongest lens is defined as the lens with the strongest power in the 180-degree meridian. It doesn't matter which lens you start with. Begin with the weakest lens first. For this purpose the weakest lens is defined as the lens with the weakest power in the 180-degree meridian. Begin with the weakest lens first. For this purpose the weakest lens is defined as the lens with the weakest power in the 90-degree meridian.

Most prescribed vertical prism

When reading a spectacle lens prescription, which lens should be verified first? If the lenses have similar powers and there is also prescribed vertical prism in the prescription, then begin with the lens with the __________________. It doesn't matter which lens you start with Most prescribed vertical prism Least prescribed vertical prism

C. It will help relax your accommodation and keep your eye from changing focus, thus assuring accurate readings

When you use a lensometer, why is it necessary to focus the eyepiece? A. It cleans the eyepiece of any smudges from previous use B. The lensometer must be used without your spectacles on. Focusing allows you to set the lensometer to your prescription C. It will help relax your accommodation and keep your eye from changing focus, thus assuring accurate readings D. There is no need to focus the eyepiece, everyone has the same facial adjustment

Right Lens If it isn't clear which lens is stronger and there isn't a prescribed vertical prism, begin with the right lens.

Which lens would you verify first in the lensometer? OD: -1.00 -1.50 x 180 OS: -1.50 -1.00 x 180 Left lens Right lens It doesn't matter which lens you verify first

titanium stainless steel

Which two are considered hypoallergenic metal frame materials? Titanium Nickel Aluminum Stainless steel

Polyamide Optyl

Which two are considered hypoallergenic plastic frame materials? Zyl Polyamide Optyl

out

You are verifying a lens with 12Δ BI. The illuminated target falls off the viewing screen and you decide to use an auxiliary prism to bring the target within view. You would place the auxiliary prism in the lens holding cell with the thicker edge oriented in/out (choose one).

Fail Fails bc larger than 2.5mm difference

You are verifying a pair of glasses and determine that the distance between optical centers is 62 mm and the patient's PD is 59 mm. You start moving the lens toward the patient's PD from the optical center until the horizontal prism reads 1/3Δ and you spot the lens at this point. You do the same for the other lens. The distance between the new dots you made is 54 mm. (The powers of the lens match and there is no vertical prism). Does the pair of glasses pass or fail based on ANSI standards?

-2.00 +3.00 x 045

You are verifying a pair of glasses. You start with the lensometer wheel in the high minus direction and turn it slowly toward the plus. The thin lines come into focus at -2.00 with the axis at 045. You keep turning in the plus direction and the thick lines come into focus at +1.00. What is the power of the lens? -2.00 -2.00 x 135 -2.00 +1.00 x 045 -2.00 +3.00 x 045 -2.00 -1.00 x 045

-3.75 -0.75 x 100

You are verifying a pair of glasses. You start with the lensometer wheel in the high plus direction and turn it slowly toward the minus. The thin lines come into focus at -3.75 with the axis at 100. You keep turning in the minus direction and the thick lines come into focus at -4.50. What is the power of the lens? -3.75 -1.00 x100 -4.50 -0.75 x 100 -3.75 -0.75 x 100 -450 +1.25 x 010

045

You measure the distance portion of a flat top bifocal and the axis reads 135. You proceed by flipping the glasses around with the temples now facing towards you to measure the distance power and then near power. What should the axis be set at now? Record your answer using a 3 digit number.

-1.50 -2.50 x 090

You measure the power of a lens in the lensometer, the thick lines come to focus at -1.50 at 180 degrees and the thin lines come to focus at -4.00. What is the power of the lens in minus cylinder form? -1.50 -4.00 x 180 -5.50 -2.50 x 090 -5.50 -2.50 x 180 -1.50 -2.50 x 090 -1.50 -4.00 x 090 -1.50 -2.50 x 180

Horizontal prism was prescribed

You take a patient's PD and compare it to the OC's found in their current pair of glasses and find there is a large difference between the two. Assuming the glasses were made correctly, why might this be? Astigmatism was prescribed Vertical prism was prescribed Horizontal prism was prescribed

Plastic

________ frames are also called zyl frames. Rimless Balgrip Half-eye Semirimless Nylon cord Combination Numont Plastic Metal

Hinges

________ holds the temples to the front of the frame. Endpieces Eyewire Rim Hinges Shield Bridge

Nylon cord

__________ frame is a frame that hold the lenses in place by a nylon cord around the bottom edge of the lens while the top of the lens is fitted into the upper rim of the frame. Plastic Combination Balgrip Metal Semirimless Numont Half-eyes Rimless Nylon cord

Rimless

____________ mountings hold the lenses in place by screws, cement, clamps, and other posts. Plastic Metal Combination Rimless Balgrip Numount Half-eye Semirimless Nylon cord

Polycarbonate

_________________ is a material usually associated with lenses, but can be molded into frames.