Unit 2 - Progressive Addition Lenses

Question 1

A progressive lens design with a gradual increase in unwanted astigmatism is considered a ______ design.

a. soft
b. hard
c. swimmy
d. dynamic

Answer 1

a. soft

Question 2

Which of the following shaped frames should be avoided when PAL are used?

a. square
b. round
c. pilot
d. all the above

Answer 2

c. pilot

Question 3

When determining the fitting cross height for a PAL patient, you should measure from the deepest point on the plane to the _____.

a. lower limbus
b. center of pupil
c. lower edge of pupil minus 1 mm
d. upper limbus

Answer 3

b. center of the pupil

Question 4

When checking the distance power of a PAL, the _____ side of the lens should face the operator.

a. convex
b. concave
c. convex for plus lenses and concave for minus lenses
d. concave for plus lenses and convex for minus lenses

Answer 4

a. convex

Question 5

If the patient must lower their head to see clearly in the distance, the lenses are positioned too high.

a. true
b. false

Answer 5

a. true

Question 6

If a patient must move the reading material to the side to see clearly, the pupillary measurements may be off.

a. true
b. false

Answer 6

s. true

Question 7

When fitting a frame to a PAL patient, _____ degrees of pantoscopic tilt is recommended.

a. 2-6
b. 6-8
c. 10-12
d. 15-20

Answer 7

c. 10-12

Question 8

______ will effectively increase the intermediate and near viewing zones for a PAL.

a. Shorter vertex distances
b. Less pantoscopic tilt
c. Frames with large nasal cuts
d. Reduced fitting cross heights

Answer 8

a. Shorter vertex distances

Question 9

Free form machining can create _____ surfaces.

a. aspheric
b. atoric
c. progressive
d. all the above

Answer 9

d. all the above

Question 10

The amount of prism used in prism thinning is equal to ____ of the add power.

Answer 10

2/3 (two-thirds)

Question 11

Which is better for new presbyopes - soft or hard PAL designs?

Answer 11

soft

Question 12

Varilux made by Essilor was the very first progressive lens marketed to the world.

a. true
b. false

Answer 12

a. true

Question 13

Asymmetrical PALs push the majority of the astigmatism to the _____ side of the lens.

a. temporal
b. nasal
c. convex
d. concave

Answer 13

b. nasal

Question 14

What is the minimum fitting height for today’s short-corridor PALs?

a. 12 mm
b. 15 mm
c. 18 mm
d. 22 mm

Answer 14

b. 15 mm

Question 15

True or false.

We can use a specialized PAL to help people in different lines of work.

Answer 15

true

Question 16

Which 5 things do we measure when fitting a patient for a PAL the traditional way?

Answer 16

1. distance PD (mono)
2. near PD (mono)
3. fitting cross height (mono)
4. vertex distance
5. pantoscopic tilt

Question 17

What do we do with the patient’s frame before we even take the measurements?

Answer 17

Fit the specs to the patient’s face perfectly (vertex distance, panto tilt, nosepads, temples, etc.)

Question 18

What is head cape?

Answer 18

Head cape is the measurement of the natural resting position of the head.

Question 19

A frame works well for a PAL patient if their fitting cross height (where it bisects their pupil) is ____ to ____ mm.

Answer 19

18-24

Question 20

What do we do after we measure the patient for the PAL?

Answer 20

Check the marked measurements on the lenses against the manufacturer’s layout chart to ensure it satisfies their requirements.

Question 21

What 3 things do we check for in the PAL distance circle?

Answer 21

1. sphere power
2. cylinder power
3. axis

Question 22

We can find the _____ on the nasal side.

a. add power
b. brand
c. PRP
d. power value

Answer 22

b. brand

Question 23

We can find the _____ on the temporal side.

a. add power
b. brand
c. PRP
d. fitting cross

Answer 23

a. add power

Question 24

You can find the add power engraved below the 180 line on the _____ side of the lens.

Answer 24

temporal

Question 25

What 3 things do we verify on the manufacturer’s cut out chart?

Answer 25

1. mono distance PD
2. horizontal prism, if ordered
3. fitting height

Question 26

True or false.

We will likely find some type of vertical prism in most lenses due to the common practice of prism thinning.

Answer 26

true