Focal plane | Wikipedia audio article
Channel: wikipedia tts
Date: 29/05/2019

This is an audio version of the Wikipedia Article:
https://en.wikipedia.org/wiki/Cardinal_point_(optics)


00:00:59 1 Explanation
00:02:05 1.1 Focal planes
00:04:21 1.2 Principal planes and points
00:05:58 1.3 Nodal points
00:07:27 1.4 Surface vertices
00:08:06 2 Modeling optical systems as mathematical transformations
00:08:59 2.1 Rotationally symmetric optical systems; Optical axis, axial points, and meridional planes
00:10:11 2.2 Ideal, rotationally symmetric, optical imaging system
00:11:58 2.3 Focal and afocal systems, focal points
00:12:54 2.4 Transformation
00:13:17 3 See also
00:13:37 4 Notes and references
00:14:17 5 External links



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SUMMARY
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In Gaussian optics, the cardinal points consist of three pairs of points located on the optical axis of a rotationally symmetric, focal, optical system. These are the focal points, the principal points, and the nodal points.  For ideal systems, the basic imaging properties such as image size, location, and orientation are completely determined by the locations of the cardinal points; in fact only four points are necessary: the focal points and either the principal or nodal points.  The only ideal system that has been achieved in practice is the plane mirror,  however the cardinal points are widely used to approximate the behavior of real optical systems. Cardinal points provide a way to analytically simplify a system with many components, allowing the imaging characteristics of the system to be approximately determined with simple calculations.