How can I determine the properties of a thin lens using basic formulas?

AI Thread Summary
To determine the properties of a thin lens, key calculations include the effective focal length, power, surface curvature, radius of curvature, format size, and Airy disk diameter. The effective focal length can be found using the formula 1/f = 1/u + 1/v, while the power of the lens is calculated as p = 1/f. Surface curvature for equiconvex lenses is given by C = 1/R, and the radius of curvature can be derived from f = 1/2*r. The discussion highlights confusion regarding the term "format size," which remains unresolved. Overall, the calculations for focal length, power, and curvature were clarified, but further information is needed to address the format size query.
AaronBurr
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Homework Statement


I've tried to attached the image of the diagram. If that isn't working please let me know.Height of incident marginal ray now 25. Assume a thin lens.
Find:
a. the effective focal length
b. the power of the lens
c. surface curvature for front and back surfaces (assume equiconvex shape)
d. radius of curvature for each surface
e. format size (assume square)
f. Airy disk diameter

Homework Equations


a. the effective focal length
1/f=1/u+1/v
F=1/2*r

b. the power of the lens
p=1/f

c. surface curvature for front and back surfaces (assume equiconvex shape)
C=1/R

d. radius of curvature for each surface
F=1/2*r

e. format size(assume square)

f. Airy disk diameter
=2.44*λ*f ⁄#

The Attempt at a Solution


With the known formulas I don't think I have enough information to solve anything besides f. and the solution to part f doesn't help solve the other parts. If I can just find the focal length I think the rest will fall into place.Can you point me towards whatever bit of information I'm missing?

Thanks so much.
 

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The f-number is the ration of the focal length to the diameter of the entrance pupil.
 
Thank you so much! I knew I was just missing something obvious! I think I've got parts a, b, c, d, and f correct. But I'm still a bit unsure of what is being asked in part e? I don't know what they mean by format size. Any ideas? Again thank you for your help.

a. the effective focal length

F-number=f/d
1/10=f/25mm
F=5/2

b. the power of the lens

p=1/f
p=1/(5/2)
p=2/5c. surface curvature for front and back surfaces (assume equiconvex shape) (Both lens have same radius of curvature)

C1=1/R
C1=1/5

d. radius of curvature for each surface

f=1/2*r
R1=2*f
R=2*(5/2)
R=5

e. format size(assume square)

??

f. Airy disk diameter

=2.44*λ*f⁄#
=2.44*587nm*1/10
=143.228
 
F = f / D
10 = f / 50 mm ...
The optical power of the lens, P, is in diopters, D, if f is in meters.
The surface curvature of a lens, C, also in diopters, is much more complicated than that of a mirror.
It is the inverse of the radius of curvature, r, in meters, of the lens.
Have a look in your textbook or notes for the formula.
 
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