Formulas

Question 1

1 cm/m

Answer 1

1 Pd

Question 2

1 pd = X degrees

Answer 2

.57 degrees

Question 3

x pd = 1 degree

Answer 3

1.75 Pd

Question 4

Sine square method

Answer 4

F = S + C(Sin0^2)

Question 5

Prism Edge Thickness

Answer 5

P= 100 g (n-1) / d

Question 6

Decentration inset

Answer 6

Frame PD - Pt. PD

Question 7

Seg Inset

Answer 7

Dist. PD - Near PD / 2

Question 8

Total Inset

Answer 8

Frame PD - Near PD / 2

Question 9

FOV

Answer 9

(d+2.7)(2h) / 2.7

Note: h is 1/2 the diameter

Question 10

Image Jump

Answer 10

Fadd x d

Question 11

Differential Displacement

Answer 11

Fsphere x d

Question 12

Total Displacement

Answer 12

(Dcyl x Fcyl) + (Dsph + Fcyl)

Question 13

Lens Power Effectivity

Answer 13

Fn = Fo / (1-dFo)

Question 14

Resultant Spherocylinder

Answer 14

S’ = So (1 + ((sin a^2)/2n)

C’ = S’ (tan a^2)

Question 15

Power Magnification

Answer 15

Mp = 1 / (1-h(Fv)

Question 16

Shape Magnification

Answer 16

Ms = 1/(1-F1(tc/n))

Question 17

Mspec

Answer 17

Mp x Ms

Question 18

Mspec %

Answer 18

(Mspec - 1) x 100 =

Question 19

Fresnel

Answer 19

R = (n’-n)^2 / (n’+n)^2

Question 20

Light Transmission

Answer 20

T = (1-R)^2 q^2

Question 21

Absorption

Answer 21

lx = lo x q^x

Question 22

n for CR- 39

Answer 22

1.498

Question 23

n for Crown Glass

Answer 23

1.523

Question 24

n for Trivex

Answer 24

1.53

Question 25

n for Poly

Answer 25

1.586

Question 26

When measuring panto tilt, how much does 2 degrees of tilt equal in movement?

Answer 26

1 mm

Question 27

What is the AR coating for Poly lens?

Answer 27

1.26

Question 28

Saggital Depth

Answer 28

S = Fh^2 / 2000 (n-1)

Note: h is 1/2 lens diameter

Question 29

What is the BC starting point for Myope?

Answer 29

SE + 8

Question 30

What is the BC starting point for Hyperope?

Answer 30

SE + 4

Question 31

Light transmittion

Answer 31

Incident - (reflection - absorption)