s***l
发帖数: 2236 | 1 The original question is about the spacial mode of a laser, not how the
shape deforms in fiber or any media when the light propagates, not to
mention frequency domain, which is almost completely irrelavant.
For a confocal resonator, the spacial mode can be analytically solved to
be Hermite-Gauss functions, in which the TEM00 mode corresponds to a simple
2D Gaussian beam.
So for edge-emitting LD, the spacial mode should be 2D Gaussian beam, although
not degenerated since the ratio of the dimentio |
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z**********n
发帖数: 39 | 2 TEM00激光在空气中传播为什么会有beam waist
他不是平行光束吗
不是学物理的，轻点拍
谢谢 |
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z**********n
发帖数: 39 | 3 3x
TEM00 is fundamental transverse mode of the laser resonator and has the same
form as a Gaussian beam.
Also, I know that diffraction causes light waves to spread transversely as
they
propagate, and it is therefore impossible to have a perfectly collimated
beam. The spreading of a laser beam is in precise accord with the
predictions of pure diffraction theory;
My question is :
why there is a beam waist without passing through any optics, for example,
objective?
Or my understanding is wrong, the |
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