Typically the FOV is defined by the user when setting up a conventional imaging system model.  Vignetting may limit the field. 

It’s not exactly clear what you application is, but I guess you simply want to know what angular range of rays make it through your prism.  Is your model sequential or non-sequential (NSC)?  If it’s NSC, then you can use a Source Ray and scan its angle at the input while using a Detector Rectangle to observe the output (in real space and/or angle space).  Alternatively, you can you a Source Two-Angle and inject a cone of rays into the input, and again use the Detector Rectangle to look at what comes out.

Maybe your looking for quite simple answer. Just use the the OPERAND “RAID “or “RANG” with the right surface No you want to see the angle of the ray reflecting and you will get the readout in RAD or DEGREEs  in the merit function. To see the max angles use the -1 and +1 at the parameter on rel. High. 

Thank you for your helpful comments Klaus.Eckerl and Jeff.Wilde

I used mixed type mode in ZOS. My model is sequenial mode imported with a CAD file through NSC editor. 

When I tried to read out Incidence Ray Angle using RAID operand, on the first surface I can make it. However, on the last suface (image surface) I can not see a readout from RAID operand. It gives error indicating “Error in target , Missed surface”. 

What am I missing here? Can you help out? 

Hey Onder,

I think that using mixed-mode is the right approach for this design. But there is a consequence in that if a ray does not exit the NS region, the sequential ray tracer has no way of knowing what happened to the ray, and hence it throws this error.

Make sure you set up the system aperture and field of view in such a way that every ray you trace into the NS entrance comes out of the NS exit port. I’d recommend ‘object-sided’ definitions of aperture and field as the easiest way to achieve this, and make sure that the exit port is large enough to pass all rays that enter the NS region.

• M