COMSOL 6.4 - Tutorial: Tracing Rays Through a Double Gauss Lens

Tutorial: Tracing Rays Through a Double Gauss Lens

In this section a simple multi-element lens will be simulated. The model will use an f/1.7, 100.2 mm focal length double Gauss lens by Lautenbacher & Brendel (Agfa Camera Werk Ag, U.S. Patent 2784643), although some materials have been replaced with equivalent optical glasses. Further details of the lens simulated in this study can be found in the tutorial Double Gauss Lens in the Application Libraries. An overview of the lens can be seen in the figure below. The table below gives the optical prescription.

Overview of a double Gauss lens. In this view the marginal rays of an on-axis trace are shown, together with the chief ray of 4 additional fields.

It should be emphasized that the ray tracing method used by Geometrical Optics interface is inherently nonsequential, so the same results can be obtained by constructing the geometry in any order. However, in this simulation the lens geometry is constructed by repeated insertions of part instances from the COMSOL Part Library with each lens element (including the stop) being inserted sequentially. Each subsequent lens is placed relative to work planes that have been defined in each of the lens (and stop) part instances.

For full details on creating the lens geometry, see Appendix — Geometry Instructions of the tutorial for the Double Gauss Lens.

Double gauss lens optical prescription
index	Name	Radius(mm)	Thickness (mm)	material	Clear Radius(mm)
—	Object	∞	∞	—	—
1	Lens 1	75.050	9.000	LAM3	33.0
—	—	270.700	0.100	—	33.0
2	Lens 2	39.270	16.510	BAH11	27.5
3	Lens 3	∞	2.000	SF5	24.5
—	—	25.650	10.990	—	19.5
4	Stop	∞	13.000	—	18.6
5	Lens 4	-31.870	7.030	SF5	18.5
6	Lens 5	∞	8.980	LAM3	21.0
—	—	-43.510	0.100	—	21.0
7	Lens 6	221.140	7.980	BAH11	23.0
—	—	-88.790	61.418	—	23.0
—	Image	∞	—	—	42.5