# Why do we see laser beams?

A laser produces a coherent beam of photons with particular $\mathbf{k}$ and $\mathbf{\omega}$.

So, if there is no particular $\mathbf{k}_0$ directed toward our eyes, why do we see laser beams?

I think this is related to the Huygens–Fresnel principle, but I wasn't sure.

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possible duplicate of How do I see things of the bright room, being in the dark room? – jinawee Apr 16 '14 at 9:20
Ever notice how you can't really see the beam of a laser pointer? – Marcin Apr 16 '14 at 14:56