How to show light ray effect

Hi all,
                Actually i want to create some very basic n simple
animations which can shown to school teachers to show how effective
eduactional content ( i.e animation) can be created using open source tool.(
If any body knows a simpler and mature 2D animation tool , plz tell me ).
but problem is that i myself is not that familliar with blender.

 I am trying to create simple animation in blender showing light rays
diffraction when passing thru a prism. ( or effects light after passing
lenses ). For showing light i thought i will extrude/ scale a plane in horz
dirction , but it was not working.
Can anybody give some suggestion/solution ? I want that moving light beam
/ray effect.

Thanx in advance

-- 
There is no point in knocking the "closed Windows" when the door is "Open".
Open your eyes, use open source software.

PLEASE VISIT & REGISTER @ "www.ossrc.org.in"

Regards,
Yogesh


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