Is there any optical component that uniformizes the incoming light?

To add to Carl Witthoft's answer: your proposed device would violate Conservation of Optical Extent aka Optical Étendue unless it were an active device (i.e. one needing a work input to "uniformise" a given quantity of light).

The law that optical extent can only be held constant or increased by a passive optical system is equivalent to the second law of thermodynamics for light, because the optical extent of a light source is its volume in phase space.

The optical extent $\Sigma$ for the light radiated from a surface $S$ is:

$$\Sigma = \int_S \int_\Omega I(x) \cos(\theta(x, \Omega)) \,{\rm d} \Omega\, {\rm d} S$$

where we integrate the intensity $I$ at each point $x\in S$ over all solid angles $\Omega$ taking account of the angle $\theta$ each component of the radiation from point $x$ makes with the surface's unit normal. Then we integrate this quantity over all points on the surface $S$.

So, the $\Sigma$ for your output would be nought, whilst it would be large for your input, so no passive imaging device can do what you ask.

So, another way of putting Carl's answer would be that the proposed device would have to "forget" the state encoded in the input light's wavefront direction at each point. Thus your proposed device, if at all possible, would needfully be an active device, needing work input of $k_B\,T\,\log 2$ joules for each bit of light state forgotten in accordance with the Landauer Principle form of the second law of thermodynamics. I say more about this in my answer here.


No. Not that you've defined "uniformize" very well here, but it appears you're asking for every ray from every source point to be directed in some parallel direction. Leaving aside self-diffraction effects, just stop and think: how would any material or device be able to accept a bundle of rays from all angles at a given point on the device, and emit them all in a parallel bundle? This would be the equivalent, say, of a mirror which reflected every incoming ray in the same direction regardless of the incoming angle.

Now, I could cheat really badly and propose a lasing medium which is pumped with all those incoming rays (i.e. absorbs everything) and emits energy in a collimated beam, but that's clearly not what you are getting at -- I hope!