Can Two Lasers Overlap and Create a Single Point of Light?

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Two laser beams can create the illusion of a single point of light when they intersect, but visibility depends on the presence of particles in the air to scatter the light. Without a medium like dust or water particles, the beams remain invisible from the side. The intersection of two beams increases the number of photons available for scattering, enhancing visibility. Techniques using intersecting lasers are employed in advanced 3D displays, either by fluorescing materials in glass or by ionizing air to produce visible light. However, these methods often require complex setups and powerful lasers, limiting practical applications.
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Is it possible two have two beams of light crossing to give the illusion of a small point of light in the air?
 
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No, you can't "see" a laser beam from the side unless the light is being scattered from something (e.g. dust). Using two lasers won't make a difference.
 
tomc said:
Is it possible two have two beams of light crossing to give the illusion of a small point of light in the air?

Yes.
Just like what happens when two searchlight beams cross. Something in the air(dust, water particles, etc...) must of course be present.
In any event, at the point of beam intersection, there are more photons available for scattering than from one beam alone.
 
Two lasers intersecting in empty space won't have any effect on each other. Two lasers intersecting in a medium that has certain illumination-dependent properties is a bit more useful.

Something similar is done in at least two different types of 3D displays. One uses two infrared lasers scanning a glass cube doped with a material that fluoresces visibly when illuminated by both simultaneously. Color can be achieved using different lasers to light up different fluorescent dopants. A block of glass big enough to be a useful display would be both massive and extremely expensive, though.
http://www.3dtl.com/page9.php

Another works in air, and instead of using multiple lasers intersecting at a point, uses a single wide beam focused to a point to ionize the air to the point that it glows. This works in open air, but requires dangerously powerful lasers, and doesn't do color. Something similar is used to "etch" 3D shapes inside a block of glass:
http://www.bathsheba.com/crystal/
 
So I know that electrons are fundamental, there's no 'material' that makes them up, it's like talking about a colour itself rather than a car or a flower. Now protons and neutrons and quarks and whatever other stuff is there fundamentally, I want someone to kind of teach me these, I have a lot of questions that books might not give the answer in the way I understand. Thanks
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