Skip to main content
Solved

what is the operand for the chief ray angular coordinates for x and y

  • November 27, 2023
  • 3 replies
  • 544 views

hi,

I would like to know how to report the angular coordinates of the chief ray relative to the vertex of a surface.

specifically, i would like to report (or know the operand) of the angular X and Y coordinates ( the X and Y in the upper left of the image below).

 

 

Best answer by David.Nguyen

Hi @John.Domm,

 

You could use RETX, and RETY, which are the real ray x-, and y-direction tangents, respectively. Then, you can apply an ATAN with Flag = 1 for degree.

In this dummy example below, I’ve a single field at X = 2.5 deg, and Y = 5.0 deg, and I’ve changed the OBJECT thickness to 200 so a spot is actually visible in the Spot Diagram. Note that I’m using a Rectangular Field Normalization.

Let me know if this helps.

Take care,

 

David

3 replies

David.Nguyen
Luminary
Forum|alt.badge.img+2
  • Luminary
  • 1159 replies
  • Answer
  • November 28, 2023

Hi @John.Domm,

 

You could use RETX, and RETY, which are the real ray x-, and y-direction tangents, respectively. Then, you can apply an ATAN with Flag = 1 for degree.

In this dummy example below, I’ve a single field at X = 2.5 deg, and Y = 5.0 deg, and I’ve changed the OBJECT thickness to 200 so a spot is actually visible in the Spot Diagram. Note that I’m using a Rectangular Field Normalization.

Let me know if this helps.

Take care,

 

David


  • Author
  • Infrared
  • 5 replies
  • November 28, 2023

Hi David

yes this works!  thank you so much!

John


Erkang Wang
  • Infrared
  • 8 replies
  • May 1, 2025

If I include more fields in the simulation, which field's chief ray angle am I calculating? Thanks!