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Variables insertion, distortion, and relative illumination

Question

1) About variables insertion, before optimizing: how can you define the distance between image and object and say for instance that it should be 27mm?
2) Variables: how can you insert distortion among certain values?
3) Where are indications about "relative illumination" of a system to be found?

Synopsis

Variables insertion, distortion, and relative illumination

Solution
Note that none of the solutions to these questions can be undertaken conveniently using OSLO Light. All three problems would require CCL commands to be written which would emulate functions that are already existing in OSLO Standard or higher. As a result, the "How To" description (part A) of each answer cannot be followed with a user using OSLO LT - the user will not find these function available. But the online help description (part B) of each answer CAN be found in the online help system of OSLO LT.

1a) You can use the ln(srfa, srfb, cfg) operand. If you had a system with surfaces 0 through 8, you would write the operand as ln(0, 8)-27

1b) For a description of this operand along with others like it, within OSLO press F1 to enter on-line help. From the "Search" tab, search on "operands" (no quotes) and then click on "Operands" from the resulting search list. Click on the "System" link to get a listing of system operands - and take a look at ln(srfa, srfb, cfg)

2a) You can have OSLO specify distortion for you. Choose Optimise>> Generate Error Function>> OSLO Spot Size/ Wavefront... from the menu structure, and in the resulting dialog box choose "Correct distortion at full field" = "On". Then click on OK to accept the other default values in this dialog box. To see the operands that were generated, choose Optmize>> Operands... from the OSLO menus and note that the last three operands in the operand list are devoted to distortion.

2b) To see how to specify these distortion operands specifically, within OSLO press F1 to enter on-line help. From the "Search" tab, search on "operands" (no quotes) and then click on "Operands" from the resulting search list. Click on the "Reference Ray" link to get a listing of reference ray operands - and take a look at dist(fpt, ray, wvn, cfg)

3a) Choose Optimize>>Support Routines>>Vignetting>> Image Illumination... from the OSLO menus. Note that in the resulting dialog box, there are two types of image illumination.

3b) For a description of this function, within OSLO press F1 to enter on-line help. From the "Search" tab, search on "illumination" (no quotes) and then click on "Illumination" from the resulting search list. Click on the "Relative Illumination" link to get a page with a brief description of the differences between the two relative illumination options.