hotspot from lightsource vs optimal placement

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http://www.mtheiss.com/sprayt1/tut1_pointlightsourceandscreen.htm

This is a simulation of a point light source and how it is effected by placement using a screen (simulated).

"Now we place the screen a little closer to the light source. The radiation distribution should be less uniform, with a higher concenctration in the center of the screen. More rays should hit the screen since it will cover a larger solid angle now.
Change the x-coordinate of the screen location from 10 cm to 1 cm and re-start the Simulation in the main window. Now the screen looks like this (20 rays/pixel as 100% white level): "

"Note the larger fraction of rays reaching the screen (38.5%). This configuration was saved under the name tu1_step2.s99. If you cannot reproduce the above result, please load this configuration and compare it to yours.
Finally we can check if the screen gets 50% of the rays if it is placed very close to the light source. Since the light source emits isotropically half of the rays should hit the screen in this case. Set the x-coordinate of the screen's position to 0.001 cm and re-run the simulation. I found a value of 49.6% (tu1_step3.s99). "

But if you look at pics you will see at optimal light useage (49.6) is right on top of lense yet imposible (heat)-the closer you are the more evident this hot spot but the more rays you capture (DUH). This shows that and I know you knew that, but what is the prog. they are using there? Can you add lens charictoristics and etc to it? Temp of light and types of bulb? These TV co's are just drawing this stuff by hand....Learn how to use that, and simulate this stuff it would be cheaper and more effective. Mess around with it till ya get a nice even pattern of light. Dunno am I way off or?


:confused:
 
Are two light sources partially canceling each other out?

http://www.glenbrook.k12.il.us/gbssci/phys/Class/light/u12l1b.html
That seems to sugest some more light loss when using two light sources (two bulbs) as it will cancel out light waves that interfear with each other , trough meets crest of light wave. But enforces when crest meets crest and trough meets trough. Add to that its 60hz (u.s. anyhow) your panel maybe 60hz and you got flicker plus a prob. with light cancelation. Now over 60hz refresh rate the flicker will not happen as much as your not in sync with power source which is strobing th elight source. I know Pc mons at 60hz are not clear looking a dim stroby kinda. This wouldnt be as noticble when projected but just as bad on the quality. Does that make sense? And check that page above its real interesting about using more than one point light source and its effects.....:)
 
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