How about this simulation program
How about this ?>
It tells me the page is unavailable.
Admin note: thread title edited from "God simulation" to 'Good simulation of lens."
Being a GeoCities page, you'll have to copy the address into the address bar. Incidently, if you renamed the file something like Lens.txt it would actually let you get around that, at least for web viewing (it will still appear as a proper image).
As for the simulator, that does look pretty nifty, though I'll admit to having no clue as to what the Arabic text is. Does it do other types of thin lenses as well?
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