Network of local minima for doublet
This web-page contains data relevant for optical system of doublet. (Please look for more information at F. Bociort, A. Serebriakov, and M. van Turnhout, Saddle points in the merit function landscape of systems of thin lenses in contact, Proc. SPIE 5523).
For a monochromatic split doublet search, the network of local minima and saddle points is shown. The systems have small equal distances between surfaces and all three independent curvatures are used as variables.
Local minima (drawn within continuous-line rectangles) and saddle points (within dashed rectangles) were obtained for a monochromatic doublet search with F number 5, field 3 degrees, and n=1.5. The lines between rectangles show how these systems are linked in a network. For the saddle points, the surfaces with nearly equal curvatures have been drawn with thick lines. The basic achromatic doublet shapes are shown within circles. The arrows indicate which monochromatic local minima leads to them, after local reoptimization for color correction. For the Reversed Gauss and Steinheil systems, the V values of the two glasses are 30 and 55 respectively. For the Gauss and Fraunhofer systems, the glass order has been reversed. At this stage, the thicknesses of the achromatic doublets have also been adjusted.
It may be, because of stagnation, that in order to obtain a "pure" local minimum you have to start optimization several times. The saddle points were obtained for following programs:
- Code V version 9.4
- Zemax version 18.09.2003
- OSLO version 6.2
Saddle points should remain till the merit function definition and local optimization algorithm are not changed.
Code V files
Zemax files
OSLO files