Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



Laser Pointer Store

Silicon Photonics

Joined
Dec 26, 2007
Messages
6,333
Likes
161
Points
0
pullbangdead i praise you, thank you very much!!!

now i understand :D.

one more thing, does light come out like A or like B?


A = going from the center to the front, like it goes perpendicularly to the "rectangle"

B = going upwards (from the rectangle)




is it A and then it bounces off a mirror?


(i am asking this because i dont know how a closed can diode would direct light off its hole, unless the diode's just pointing upwards and no mirror is needed)
 

Joined
Aug 25, 2007
Messages
2,045
Likes
121
Points
0
^Very good question, and actually, you got it mostly right.

The light is actually emitted in all directions at first, just like with an LED. The coherent light that makes it a laser, however, comes from the light that is emitted in both your A and B directions. There is a good mirror that reflects all of the light traveling in the A direction, and a semitransparent mirror that reflects some of the light traveling in the B direction, but allows some of the light from the B direction to leave the diode.

Look at the name "laser": light amplification, by stimulated emission of radiation

What makes it a laser is that the light traveling back and forth in the A and B directions is amplified because it stimulates the emission of more photons as it travels through the diode. And because the extra photons were stimulated, any photon that was stimulated will be coherent with the original photon that caused it to be emitted.

So basically, light is traveling in both the A and B directions, bouncing back and forth and getting brighter as it travels and causes more photons to be emitted. Some of the photons will pass through the semitransparent mirror in the B direction, resulting in a laser beam: a coherent beam of photons.
 

artix

New member
Joined
May 24, 2008
Messages
994
Likes
1
Points
0
Why do you need to post in this thread? Just look how old it is!

Next time when your reading old threads, don't comment unless it's really important. :)
 

Traveller

New member
Joined
Dec 21, 2008
Messages
1,223
Likes
74
Points
0
Artix said:
Why do you need to post in this thread? Just look how old it is!
I thought the content would be interesting to other "newcomers" so I BUMPED it.

I take it next you're going to tell me that bumping thread's are a big no-no around here, ...right? So fine, go ahead and sue me... ;)
 
Joined
Dec 26, 2007
Messages
6,333
Likes
161
Points
0
pullbangdead said:
^Very good question, and actually, you got it mostly right.

The light is actually emitted in all directions at first, just like with an LED.  The coherent light that makes it a laser, however, comes from the light that is emitted in both your A and B directions.  There is a good mirror that reflects all of the light traveling in the A direction, and a semitransparent mirror that reflects some of the light traveling in the B direction, but allows some of the light from the B direction to leave the diode.

Look at the name "laser": light amplification, by stimulated emission of radiation

What makes it a laser is that the light traveling back and forth in the A and B directions is amplified because it stimulates the emission of more photons as it travels through the diode.  And because the extra photons were stimulated, any photon that was stimulated will be coherent with the original photon that caused it to be emitted.

So basically, light is traveling in both the A and B directions, bouncing back and forth and getting brighter as it travels and causes more photons to be emitted.  Some of the photons will pass through the semitransparent mirror in the B direction, resulting in a laser beam: a coherent beam of photons.

I realized I never thanked you for this great information.

THANKS! :) It was really helpful and it took all those questions out of my mind for good.
 

PhotonSky

New member
Joined
Mar 28, 2009
Messages
78
Likes
1
Points
0
Traveller said:
[quote author=Artix link=1206394336/0#19 date=1231207407]Why do you need to post in this thread? Just look how old it is!
I thought the content would be interesting to other "newcomers" so I BUMPED it.

I take it next you're going to tell me that bumping thread's are a big no-no around here, ...right? So fine, go ahead and sue me...  ;)
[/quote]

Don't worry whenever you bump an old thread somone has to come and yell at you.

It's not that bad unless you do it lots.
 




Top