Learning Forum

[dr22phc1r46]

Hii everyone,

I was currently going through a problem, I was trying to calculate the lateral shift due to glass slab in Zemax. I took a glass slab and gave the incident angle to be 45 degree. But as soon as I try to correct the lateral shift induced by decentering the image plane, my theoretical value do not match with what zemax is giving. Apparantly I realised that the value zemax is giving is similar to the value we get while we calculate for displacement due to secondary reflection and dividing it by half.  

Why does zemax considers value of displacement due to secondary reflection and not the lateral displacement?

[Kirill]

Dear Subscriber,

Could you provide more context for your simulation? How exactly are you obtaining the theoretical value, and how are you determining the corresponding displacement value in OpticStudio?
Screenshots and sketches would be helpful as well.

Best regards,
Kirill

[dr22phc1r46]

Yes, Sure.

Actually, I used below given setup with angle of incidence as 45 degree and thickness 4mm and calculated value of s which think shows lateral displacement.

For zemax I used BK-7 material and tried inducing 45 degree angle for the glass slab by using coordinate break. Now to correct I tried to take chief ray as reference for a decentre and thought that it will be correcting the shift by moving image plane. But my theoretical value is not matching with the zemax. Any suggestions???

 

Below I am sharing my layout and lens data editor for shift correction.

This shift I corrected by taking chief ray in solve type at decentre for Y column in the coordinate break surface after the last second surface.

[dr22phc1r46]

hii, any updates???

[Christophe Weisse]

Hello,
Thanks for sharing the details of your request.
I'm a bit confused, though, as the value for s I can compute (1.338) is rather close to the chief ray solve that is automatically computed for the Y decenter (1.340):



Another way to look at this is keep the image plane aligned with the incoming ray and check the Y position of the ray with the REAY operand:



I'm thereofre not sure where the discrepency you're describing is coming from ?

[dr22phc1r46]

yes , but i want to compute the value for x and not s.