Sometime ago, I started converting an old Excel tool of mine -- "OpticsLite," still available through OptiBoard -- into a Visual Basic application. During a recent vacation, I managed to finish the first "module" on ray tracing and lens analysis. (Details of the actual ray tracing sequence can be found in Jalie's Principles of Ophthalmic Lenses.) I am making this initial module available now, since it may be awhile before I have enough spare time to finish the next one. Note that this is only a beta version.
Just a few usage notes:
1) Move the red reference line to determine the off-axis performance at a given point.
2) You can manually input variables by clicking the "Input" button.
3) If the surface curves are too steep for a given blank size, the blank diameter is reduced in size automatically in order to compensate for this.
4) The graph shows the tangential (red) and sagittal (green) power errors.