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

LPF Donation via Stripe | LPF Donation - Other Methods

Links below open in new window

ArcticMyst Security by Avery

I request more yellow

Joined
Jul 4, 2008
Messages
2,036
Points
48
It will, frequency and wavelength while related are still two different things. :whistle:I get what you mean ... the whole SHG/SFG thing involves stuff at quantum levels ... it's all very complicated, I didn't even read far into it due to it's complexity.

The amazing thing to me is that they've matched countless equations to everyday things, and how directly these equations factor in to our real life. Like when I learned about quantum tunneling, I thought it was just a math trick (it's like teleportation based on probability) until I learned that modern semiconductors make use of it. It seems like the accepted laws of reality don't even apply way down on that scale. Needless to say, it gets very complex.
 





D

Deleted member 8382

Guest
glad that I could help you. always here for what you need ;)
 
Joined
Apr 29, 2007
Messages
1,076
Points
0
You're right. Dammit, I asked my physics teacher about this and he says these laws do not apply the same to photons. I guess that's why I used the :confused: smiley. Oh well, I guess I'll have to wait to take wave phys. next year.

will

You physics teacher is full of shit then.
 
Joined
Apr 29, 2007
Messages
1,076
Points
0
why? He just said that energy conservation equations don't work exactly the same when talking about photons.

will

Energy conservation still works exactly as it would anywhere else. Energy is neither created nor destroyed.
 
Joined
Jul 4, 2008
Messages
2,036
Points
48
Energy conservation still works exactly as it would anywhere else. Energy is neither created nor destroyed.

By energy conservation he meant the equations P=mv and k=mv^2. He said that the equations were different when talking about photons, particularly because in this case v is a constant.

will
 

diachi

0
Joined
Feb 22, 2008
Messages
9,700
Points
113
By energy conservation he meant the equations P=mv and k=mv^2. He said that the equations were different when talking about photons, particularly because in this case v is a constant.

will


V must be constant in both of those equations. Otherwise they don't work - you cannot use those equations with something which is deccelerating or accelerating.

The problem with photons is that they are simultaneously waves AND particles. When observed under certain conditions they will act as waves, under others they will act as particles.

Also, it's Ek=½mv^2
 
Last edited:
Joined
Jul 4, 2008
Messages
2,036
Points
48
V must be constant in both of those equations. Otherwise they don't work - you cannot use those equations with something which is deccelerating or accelerating.

The problem with photons is that they are simultaneously waves AND particles. When observed under certain conditions they will act as waves, under others they will act as particles.

Also, it's Ek=½mv^2

right, sorry, I was typing off the top of my head lol. And yeah, he also said something about how photons can act like waves.

will
 

Asherz

0
Joined
Jan 18, 2009
Messages
1,623
Points
0
I'm doing waves in my Physics unit at the moment, got my exam on the 18th and from what I've been taught so far about light is that it has the nature of both particles and waves, and consists of both electric and magnet waves on perpendicular axis to create an electromagnetic spectrum. The modern quantum theory of light consists of particles called photons, which are packets "quanta" of energy which move at the speed of light.

As you can see both quantum and the classical theory are correct because using experiments like the dual slit one, you can see it acts as waves and particles :)

I hope this correct? I'm still learning my self.
 

diachi

0
Joined
Feb 22, 2008
Messages
9,700
Points
113
I'm doing waves in my Physics unit at the moment, got my exam on the 18th and from what I've been taught so far about light is that it has the nature of both particles and waves, and consists of both electric and magnet waves on perpendicular axis to create an electromagnetic spectrum. The modern quantum theory of light consists of particles called photons, which are packets "quanta" of energy which move at the speed of light.

As you can see both quantum and the classical theory are correct because using experiments like the dual slit one, you can see it acts as waves and particles :)

I hope this correct? I'm still learning my self.

That's pretty much correct going on the understanding that I have of the subject. :)
 
Joined
Oct 5, 2009
Messages
150
Points
0
1694-img-1304.jpg

1729-img-1324.jpg
 
Joined
Jun 9, 2009
Messages
133
Points
0
Theory
A number of nonlinear optical phenomena can be described as frequency-mixing processes. If the induced dipole moments of the material respond instantaneously to an applied electric field, the dielectric polarization (dipole moment per unit volume) P(t) at time t in a medium can be written as a power series in the electrical field:

Here, the coefficients χ(n) are the n-th order susceptibilities of the medium. For any three-wave mixing process, the second-order term is crucial; it is only nonzero in media that have no inversion symmetry. If we write

where c.c. denotes the complex conjugate (E1 and E2 being the incident beams of interest), the second-order term in the above expansion will read

where the summation is over

The six combinations (nx,mx) correspond, respectively, to the second harmonic of E1, the second harmonic of E2, the optically rectified signals of E1 and E2, the difference frequency, and the sum frequency. A medium that is thus pumped by the fields E1 and E2 will radiate a field E3 with an angular frequency ω3 = m1ω1 + m2ω2.
Note: in this description, χ(2) is a scalar. In reality, χ(2) is a tensor whose components depend on the combination of frequencies.
Parametric generation and amplification is a variation of difference frequency generation, where the lower-frequency one of the two generating fields is much weaker (parametric amplification) or completely absent (parametric generation). In the latter case, the fundamental quantum-mechanical uncertainty in the electric field initiates the process. ^
:eek::confused::wtf: ^
^and that is how I feel about this^
 
Joined
Feb 28, 2008
Messages
573
Points
0
I know these are old (haven't taken any new ones lately as yellows don't like cold weather - they are hard to start, even on fresh batteries, if the temp is under 65 degrees F) but perhaps some of you may not have seen them. This is a CNI pointer that's the same model as the LaserGlow Vega.

1da.jpg

dc7.jpg



An multi-line argon with a yellow laser mixed in:
6cb.jpg


Sorta kinda yellow (actually more orange) - red and green lasers mixing:
d8a.jpg
 
Joined
Jul 1, 2009
Messages
1,679
Points
0
yea those are some of the best yellow beamshots I've seen Schrecken_Licht.

BTW, I remember you saying last time that you needed some more diffraction gratings. I'm holding a few for you because I ran out on you last time. I sent you a PM a month ago I think.
 

cmak

0
Joined
Jan 12, 2010
Messages
716
Points
28
useful information + :kewlpics: = epic thread.

:bumpit:
 




Top