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

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Homework Help Overview

The discussion revolves around determining various properties of a thin lens, including effective focal length, power, surface curvature, radius of curvature, format size, and Airy disk diameter. Participants are exploring the relationships between these properties using established formulas in optics.

Discussion Character

  • Exploratory, Conceptual clarification, Mathematical reasoning, Problem interpretation

Approaches and Questions Raised

  • Participants are attempting to apply known formulas to find the effective focal length and other properties of the lens. There is uncertainty regarding the information needed to solve for certain properties, particularly the format size. Some participants are questioning the definitions and implications of the terms used in the problem.

Discussion Status

Some participants have made attempts to calculate specific properties, such as the effective focal length and power of the lens, while expressing uncertainty about the format size. Guidance has been offered regarding the relationship between focal length and diameter, as well as the complexity of surface curvature calculations. Multiple interpretations of the problem are being explored.

Contextual Notes

Participants note a lack of sufficient information to solve all parts of the problem, particularly regarding the format size. There is an assumption of an equiconvex lens shape, and some participants are referencing textbook formulas for further clarification.

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.
 

Attachments

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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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