Geometrical Optics (Done)

Question 1

L<0 indicates a _______ object.
L’<0 indicates a _______ image.
L>0 indicates a _______ object.
L’>0 indicates a _______ image..

Answer 1

Real, Virtual, Virtual, Real

Question 2

L’ = F + L

Answer 2

l= n/L or l’= n/L’

Question 3

Concave: interface wraps around the _________ medium.

Convex: interface wraps around the _________ medium.

Answer 3

Lower, Higher

Question 4

What is the power of a planoconvex thin lens whose curved surface has a radius of curvature of 3 cm? Assume it is a glass lens.

Answer 4

F= (1.5-1.0)/ (0.03)= +16.6 D

Question 5

f’ = n/F

Answer 5

f= -n/F

m= hi/ho = L/L’ =l’/l

Question 6

What is Total Internal Reflection?

Answer 6

TIR exists when the angle of incidence > the critical angle»light will be reflected internally

> > Note that TIR is only possible if n2

Question 7

What is the Equivalent Power formula?

Answer 7

F = F1 + F2 - (t/n) F1 X F2

Question 8

What is the Back Vertex Power formula?

Answer 8

Fv = F2 + (F/1-(t/n) F1)

Question 9

What is the aperture stop in a system?

Answer 9

Physical entity that limits the amount of light passing into an optical system when viewing an object
»aperture stop limits the field of view.

Question 10

What is the Entrance Pupil?

Answer 10

The IMAGE of the aperture stop formed by lenses IN FRONT OF IT
»If there are no lenses in front, the entrance pupil itself is the aperture stop.
»entrance pupil subtends the smallest angle

Question 11

What is the Exit Pupil?

Answer 11

IMAGE of the aperture stop formed by lenses BEHIND it.

Question 12

Is the ocular lens (+) or (-) in a Keplarian telescope?

Answer 12

POSITIVE as well as objective lens (+) (+)
Galilean telescope (-) ocular lens, (+) objective

Question 13

Why does pinhole improve vision?

Answer 13

Pinhole will INCREASE depth of focus

> > Depth of field is similar to the Horopter, but monocular

Question 14

A short focal length leads to a ________ depth of field.

Answer 14

Large depth of field

Question 15

A _________ lens will decrease field of view.

Answer 15

PLUS

Question 16

A _________ lens will increase field of view.

Answer 16

MINUS

Question 17

What is the circle of least confusion?

Answer 17

The COLC is the point of best focus for a lens (located dioptrically between the two line images that are formed in the principal meridians)
»>COLC is like spherical equivalent.

Question 18

Consider a real object 40 cm in front of a concave mirror with radius of curvature 18 cm. Find the conjugate image and the magnification (m).

Answer 18

F = 2(1)/0.18 = 11.1 D

L' = F + L
L' = 11.1 + (-2.50) = 8.6 D

l’ = 1/L’ = 11. 6 cm Finally m= L/L’ = -2.50/8.60 = -0.29

Question 19

What type of cylinder and axis is induced when increasing pantoscopic tilt of a minus lens?

Answer 19

Minus cylinder X 180

Question 20

What type of cylinder and axis is induced when increasing pantoscopic tilt of a plus lens?

Answer 20

minus cylinder X 090 (or plus cylinder x 180)

Question 21

What type of cylinder and axis is induced when increasing Faceform tilt of a minus lens

Answer 21

minus cylinder x 090

Question 22

What type of cylinder and axis is induced when increasing Faceform tilt of a plus lens?

Answer 22

minus cylinder x 180 (or plus cylinder x 090)