Hi. I am working on designing projection optics where the object is a source with diverging angle of 24 degree. I used object cone angle definition and used telecentric object space feature to correctly model source. I am able to optimize the system for all the desired constraints except for one, the field of view in image space. The system produces collimated output (afocal in image space) and i want the full angle to be 24 degree. Upon manually measuring the lengths in layout window and calculating the theta, the approximate value comes out to be more than whats desired. How can i accurately know the value of theta? How can i optimize the system for desired value of theta?