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Performing paraxial ray tracing

Question

How do I perform paraxial ray tracing in OSLO? This would be useful to set up first order properties of some complicated lens systems.

Synopsis

Performing paraxial ray tracing

Solution

"When optical designers first set up an optical system, they sometimes like to enter components as thin lenses. You can do this in OSLO by simply entering lens components with zero lens thicknesses. Some designers also find it convenient to initially enter all lens indices with a value of 2.0. With an index of 2.0, the power of a lens with one surface curvature (the other surface being a flat) is simply one (1) divided by the radius of curvature of the surface. After setting up an entire system in this manner, the lenses can then be made "real" during a process of thickening up the lenses and giving them valid refractive indices.

During this initial design stage of setting up a lens system, it is valuable to perform paraxial ray tracing and determine paraxial constants (otherwise called first-order properties, such as Effective Focal Length, F/Number, ...etc.). Paraxial ray tracing can be accomplished by choosing "Evaluate>>Paraxial Ray Analysis" from the OSLO menu. A description of the output of these analyses can be found in the online help or by clicking on the *PARAXIAL TRACE or *PARAXIAL CONSTANTS designation in the text output window."