Blazed Grating: Difference between revisions

From QT5201U wiki
Jump to navigation Jump to search
Created page with "Using a repetivive structure, it can separate a beam into different wavelengths <math>\lambda_m</math>: <math>a(\sin(\theta_i)+\sin(\theta_r))=m\lambda_m</math> Where <math>..."
 
No edit summary
 
Line 7: Line 7:
[[File:blazing.png|thumb|600px|]]
[[File:blazing.png|thumb|600px|]]


The actual reflection is done in the grating facet, incident light makes an angle <math>\theta_i-\beta</math> with the facet normal and gets reflected at the same angle, If we change to the surface normal, we get the relation:
In our type of blazing we only focus on the -1, 0 and +1 orders, all other orders are small enough to be negligible. For the +1 order the reflection is done in the grating facet, incident light makes an angle <math>\theta_i-\beta</math> with the facet normal and gets reflected at the same angle, If we change to the surface normal, we get the relation:
<math>\theta_i-\theta_r=2\beta</math>
<math>\theta_i-\theta_r=2\beta</math>

Latest revision as of 23:25, 28 February 2021

Using a repetivive structure, it can separate a beam into different wavelengths λm:

a(sin(θi)+sin(θr))=mλm

Where θiand θrare the incidence and reflective angle respectively.

In our type of blazing we only focus on the -1, 0 and +1 orders, all other orders are small enough to be negligible. For the +1 order the reflection is done in the grating facet, incident light makes an angle θiβ with the facet normal and gets reflected at the same angle, If we change to the surface normal, we get the relation: θiθr=2β