LASER and its wave-front?

Question

Light is supposed to travel as waves in a conical shape from the point of its source.......

LASER is supposed to travel in a straight line, so isn't the LASER a form of light?, if it is indeed light, then how come it wave doesn't progress in an expanding conical form?

Answer 1

yes laser can be consider as a form of light, what you ment by conical shape is that a light source gives out light in all direction, for which the intensity of the light decrease as the distance away from the source increases. lasers lights which are usually monochromatic thus they are usually coloured, are light that is produced from a high energy source and concentrated in one direction by seting an apparatus near the source. a very simple example, a magnifier can concentration light in one direction or point, this is same idea for laser, it's not the nautre between light and laser that's different, it's just that laser light is modified using instrument to produce such effect. i not going into the detail of how laser is produced because i think it will make the whole thing easier to understand for you

Answer 2

lasers are mostly produced as beams . if you use a lens you can expand the beam conically .there is no essential difference between light and laser . In laser light some specifications of light are enhanced and exaggerated.using a lens you can focus light to form the image of the light source not a point , but laser can be concentrated as a point .

Answer 3

1- Light isn't expanding in a conical shape, who said that, it expands in all possible 3-D directions depending on the SOURCE of the light
2- A laser is an INVENTION, which at first in it's first device required TWO fields on opposite sides (one magnetic, and the other electric) to prevent the laser from taking another pass other than a straight line

So in short, a laser is made out of light by accelarating partices to an ultimate speed before concentrating them as much as possible then releasing them in a DEFINED direction

ex: Sun's light expands in ALL DIRECTIONS
Laser pointer expands in a SINGLE direction

Answer 4

Light expands normally as incoherent light - a sort of random assemblage of waves.
LASER (light amplification by stimulated emission of radiation) is light, but coherent light with all troughs and peaks in phase. There is no interference (very minimal) in the beam, and it does spread but very minutely.
A laser cavity contains two extremely perfectly ground mirrors, one at each end, one fully silvered, and one partially. The lasing substance may be a gas, or a liquid, or a solid. Energy in the form of light is pumped into the laser, and the substance tends to have it's electrons "pumped up" into a higher energy state, and release the quanta or wavicle as the electrons fall to the original energy state so that it is in phase with the standing wave in the laser, and this energy escapes through the partially silvered side of the laser, the waves in a very compact and intense form, the coherence allowing for immense density of energy. The coherence allows "light amplification"
due to density of energy, and the "stimulated emission of radiation" allows the coherence.

Answer 5

A laser beam does diverge--try shining one against a distant wall and have a friend measure the size of the spot it makes. Just don't try to hit any aircraft--the spot will cover most of the plane, dazzle the pilots, and you can be heavily fined.

For a "cone" of any divergence, you can always select a small part of it by putting it through a tube. Up to a point, the thinner the tube, the less the rays in the tube will diverge--otherwise they's hit the side of the tube and you'd never see them. This is essentially what's happening with the laser beam.