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Magnifying Light

Postby Cremedelacreme48 » Wed Nov 21, 2007 8:14 am

I finally decided on a topic. I am going to try and increase light in a room without upgrading power usage or wattage of the light bulb. I will be stirctly using optical components. I've researched units of light (lumens, footcandles, etc.) But the question I have is do simple lenses increase visible light of lumens at all? Is the light they refract visible?


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Postby Craig_Bridge » Tue Nov 27, 2007 7:58 am

You might want to do a search for "lens refraction". One hit that I found was

You should do a search on "conservation of energy" from a physics standpoint. One hit that I found was

Lenses and reflectors are primarily "passive". They certainly do not produce light energy. They may absorb some light.

You might want to think about an imaginary experiment where you paint two identical 8x10x8 foot rooms including all walls the ceiling and floor two different colors, say one is a dark brown or gray and another is white. If you put an identical 100 watt bare bulb in same spot and turn them on in both rooms, which room appears to have more light in it? With identical light sources, they both started with the same amount of light. The difference in appearance will be tied to the reflectance of the paint.

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Postby ChrisG » Tue Nov 27, 2007 12:57 pm

Craig's response reminded me of another question: Cremedelacreme48, Are you considering the total amount of light arriving everywhere in the room , or the amount of light arriving at some particular location in the room (e.g. the floor)?

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