Solved

# Mirror coordinate break and polarization

• 2 replies
• 96 views

+1
• Visible
• 15 replies

Hi,

Normally when we create CB for mirrors, we will set it up with tilt type (x-tilt, or y-tilt) and reflect angle.

Can anyone kindly let me know how does “ tilt about Z” work?  Does it change the light propagation direction?

As shown below, when I add 135 deg tilt about Z to mirror 2, the polarization on the dummy surface after mirror 2 become 45 deg linear polarized light from vertically polarized light as input, why?

Thanks,

Ying

icon

Best answer by Ethan 23 December 2022, 04:16

View original

### 2 replies

Userlevel 2
+2

Hi @Ying,

Apologies on the delayed response to your question. In case this question is still relevant or for the benefit of others, I wanted to make some comments.

Generally, the Z-Axis is the direction of propagation or the “Optical Axis.” If the surface is standard and perpendicular to the Z-axis, then rotating about Z has little effect because often the optical surface is radially symmetric (and the beam is symmetric as well). In other words, if a lens rotates for instance 90 degrees, you won’t see any difference in the optical performance because the beam still sees the same surfaces.

However, if you rotate a system that does not have a radially symmetric beam, as in your case, you will see a change. I created a simpler example to demonstrate:

If we rotate the optical axis 45 degrees, the politization is still vertical but the politization seen by Surface 4 is now rotated by 45 degrees.

I hope this explanation better clarifies what happens when you rotate about the Z-axis.

Best,
Ethan

+1

Hi Ethan,