New answers tagged lenses
2
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Is power of a lens in a medium $1/f$ or $n/f$?
I hope you have heard about the Lensmaker's equation. This can be easily derived using basic laws of refraction.
$$\frac{1}{f} = (n_{21}-1)\left( {1\over R_1} - {1\over R_2} \right)$$
For a thin lens(...
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Thin biconvex converging lens problem
Summary (incoming ray defined by angle $\alpha$ and intersection with optical axis $x$, outgoing ray intersects with optical axis at $l$):
\begin{align}
\frac{x}{y}&=\frac{z}{f},\qquad\frac{y}{l}=\...
- 66
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Thin biconvex converging lens problem
If you want to locate an image formed by a lens by means of ray tracing, you need to consider an extended object, traditionally an arrow perpendicular to the axis, with its tail on the axis. Then ...
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Accepted
Thin biconvex converging lens problem
I think a better rule for a convex lens is - "All parallel rays through a lens meet in one point of the focal plane" - this point is (obviously) the point where the ray through the center of ...
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Mathematical description of the curve of a straight line in optics
The curvature you are visually experiencing is a product of the cornea's surface bending the visual field. The cornea is very similar in dimensions from person to person. So the overall domed ...
0
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ABCD Matrix for an aspheric lens
ABCD matrices are only applicable for the paraxial region, where rays travel close to the optical axis. The function of an asphere is that the description of rays traveling through them are not just ...
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How could I manually find the field of view of a camera lens at specific focal lengths?
The question is a bit more complex than you might think. I'll assume you mean angular FOV.
First of all, focus distance affects the FOV (it's called "breathing"). Because of that, most ...
3
votes
Making sense of positive and negative systems for eyeglass prescriptions
Adding spherical power and cylindrical power isn't like adding apples and oranges (or mass and length)!
...
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1
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In a ray diagram for a camera the focal point is in between the lens and sensor, is this not wrong?
But when drawing a ray diagram for the object, lens and sensor the
focal point ends up in-between the sensor and lens.
There are some semantic issues here. The focal point of the lens or the focal ...
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