2013-07-01Prof.Herbert GrossFriedrich Schiller University JenaInstitute of Applied PhysicsAlbert-Einstein-Str 1507745 JenaSolution of ExercisesLecture Optical design with Zemax for PhD-Part 1010.1 Field lens flattenerA field lens near to the image plane can help to correct a system for field curvature.a)Load the f 50 mm lens AC 300-050-C of the Thorlabs lens catalog.let the incoming light be acollimated beam at =0.55 um with a diameter of 10 mm.Define the three field points for initail fieldangles of 0,3 and 5 degree.b)Calculate the Seidel bar diagram and the spot diagram.What are the dominant aberrations of thesystemc)Introduce a concave-plane field lens with thickness 5 mm.What is the preferred material and whatis the best focal length to correct the system for Petzval curvature The distance between theachromate and the field lens should be optimized only on axis.d)What is the result,if the spot is optimized for all field points10.2 ApochromateAn apochromatic lens shows a common image location for at least three wavelengths.a)Load the achromate LAO-100.0-30.0 from the CVI Melles Griot catalog.Define an entrance pupildiameter of 25 mm and the color sequence e-F-C.The variation of the intersection length with thewavelength can be seen in the diagram,which is obtained in the menue ANALYSISMISCELLANEOUS CHROMATICAL FOCAL SHIFT.b)Add a third thin cemented lens with the material BK7.Establish a chromatical focal shift,which isidentical for the three chosen wavelengths.The numerical aperture of the system should bemaintained.Can the apochromatic correction be obtainedc)Now choose different glass combinations to achieve an apochromatic correction.In particular thematerials with anormal partial dispersions like FK54 or KZFSN4 should be checked.10.3 New Achromate and wide field systemA new achromate is a cemented component,that is optimized for large field applications.In this case,the Petzval condition is the basis for the refractive power distribution and the achromatization is nolonger a correction goal.In this case,a large difference in the refractive indices is more important thana large spreading of the Abbe number.a)Establish a classical achromate made of BK7 and SF6 with focal length f 100 mm and an objectat infinity from the scratch.Insert a stop 20 mm before the lens and select the wavelength 546.07 nmand an entrance pupil diameter of 4 mm.The system should be used on axis andfor a maximum fieldangle of 20.Optimize the radii for the default merit function and evaluate the system performance.b)Extend the system to a finite imaging system with magnification m =-1 by doubling the system.The first group of lenses should by reversed and the stop is in the middle of the system to get acomplete symmetric layout.What is the dominating aberration.Insert a second field point in the zoneof the field at14°.1/22c)Now the second part of the symmetric system is scaled down by a factor of 2.This delivers asystem with a magnification of m=-0.5.Therefore we no longer have a symmetric layout.Whathappens with the system qualityd)To improve the system add two meniscus lenses made of SK12 near to the cemented componentstowards the stop with the exact 1:2 scaling.Optimize the radii to improve the system while preservingthe mirror-symmetry.Can the astigmatism be removede)Now optimize the radii without any anti-symmetric constraints.Show,that the performance can beimproved significantly.Finally enlarge the numerical aperture of the system to a value,that is justbelow the diffraction limit.To have some more degrees of freedom,the distances around themeniscus lenses are also set as variable.To guarantee a useful solution,the magnification (PMAG-0.5)and the overall length of the system(TOTR 190.5)must be forced in the merit function to beconstant.Show,that the field curvature is corrected by the mensicus shaped lenses to a very goodflattened field.