Objectives
- Observe imaging properties of a lens
- Determine a lens focal length using thin lens equation
- Determine magnification and compare to expected
Introduction
The thin lens equation describes the imaging distances of a lens based on its focal length and object position. The linear magnification produced by a lens is defined as the ratio of image/object heights.
Thin lens equation |
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p - object distance
q - image distance
f - focal length
h - height |
Image magnification |
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The diagram here shows the three principle rays from one point on the object. Two of these rays extend through a focus point and run parallel to the axis on the other side of the lens. The third ray extends un-deviated through the center of the lens.