Changing Laser Pulse Energy for Q-Switching Solid State Lasers

AI Thread Summary
In Q-switching solid state lasers, it is possible to change the energy of a laser pulse without altering the wavelength by adjusting parameters such as repetition rate, pulse width, and overall power of the laser system. The energy of a laser pulse is determined by the number of photons involved, rather than solely by the wavelength, which is governed by the equation E = h/cλ. Increasing the repetition rate effectively boosts the energy output while maintaining the same wavelength. Additionally, manipulating pulse width can also influence the energy of the laser pulse. Understanding these factors is crucial for optimizing laser performance.
predrummer
Messages
3
Reaction score
0
Hi to you all,

I have a quick question about laser pulse energy.

For Q-switching solid state laser source, can you change the energy of a laser pulse without changing the wavelength? If so, how?

Thanks so much...
 
Science news on Phys.org
I'm not sure what you are asking. You should be able to increase or decrease the energy in the pulse to a varying degree that is within the operational range of the laser. Did you have a more specific question?
 
Unfortunately, my knowledge in this area is not deep. As far as I know, the energy of the photons, and the laser, will only change when the wavelength changes, as necessitated by:

E=\frac{h\ =\ 6.62606876(52)\ \times\ 10^{-34}\ J\ s}{λ}.c

where E is the energy, h is the Planck's constant, c is the speed of light and λ is the wavelength.

So, when we try to increase the energy of the laser in our process, I don't know it is done by either changing the wavelength or any other way.

Hope this makes things clearer.
Thanks.
 
Yes, it is right. I just realized the formula is just for one photon. :) When calculating the laser pulse energy, you have actually much more photons. So considering the laser pulse, by changing the repetition rate, you can increase the energy of the laser pulse without changing the wavelength. You can even manipulate by playing with pulse width and power of the laser system you have.
Have a look at the laser pulse calculator from the link to see the real contributions of the parameters to pulse energy:
http://www.calctool.org/CALC/phys/optics/pulsed_source
 
Thread 'A quartet of epi-illumination methods'
Well, it took almost 20 years (!!!), but I finally obtained a set of epi-phase microscope objectives (Zeiss). The principles of epi-phase contrast is nearly identical to transillumination phase contrast, but the phase ring is a 1/8 wave retarder rather than a 1/4 wave retarder (because with epi-illumination, the light passes through the ring twice). This method was popular only for a very short period of time before epi-DIC (differential interference contrast) became widely available. So...
I am currently undertaking a research internship where I am modelling the heating of silicon wafers with a 515 nm femtosecond laser. In order to increase the absorption of the laser into the oxide layer on top of the wafer it was suggested we use gold nanoparticles. I was tasked with modelling the optical properties of a 5nm gold nanoparticle, in particular the absorption cross section, using COMSOL Multiphysics. My model seems to be getting correct values for the absorption coefficient and...
Back
Top