Laser Definition and 1000 Threads

I was wondering you if you could use a laser to put out a fuse or to stop combustion? Could you use some form of laser/laser cooling to put out an explosion mid-explosion?

The Telegraph is running this story with little detail. https://www.telegraph.co.uk/world-news/2022/05/18/russia-claims-laser-weapon-can-destroy-drones-1500km-earth But, is such a laser possible? Wouldn't it scatter, and how much energy would be absorbed by the atmosphere?

Hello! I have a laser with only one input for external signals. Currently I use that to send the error feedback signal when I measure the power transmission from my cavity (not using PDH). If I want to use PDH, I would need to modulate the laser frequency, which means that I need to send to the...

ρ_kdk = k^2/π^2 dk is the density of field modes (what we are trying to solve for here), and as ρ_kdk = ρ_λdλ, and k=2π/λ, we can rearrange this to get ρ_λdλ = 8π/λ^4dλ This is where my confusion lies. I am not sure what to do next. I know this equation physically means the number of modes per...

Hello smart folks! I recently discovered this item in the estate of a former space shuttle engineer. He was responsible for replacing major components on the space shuttles as well as the crawler. It has no property markings…only the laser warning sticker. My curiosity has me here to...

Hello! I am a bit confused about locking a laser to a stable cavity in practice. I understand there are 2 stages. In the first one you scan the laser frequency and the signal you see on an oscilloscope is made of peaks corresponding to when the laser is on resonance with the cavity. In this step...

This is pretty out there so bear with me. Imagine a brunch of aliens having gravity under fine-grained control. So much so, in fact, that they'd bend space around a star so all the light would be forced around to exit from a circular aperture.No Loss. Furthermore they could bend space in front...

A red laser with the diameter of 3mm is directed towards a piece of glass. It has the effect, P of 1mW. The angle of incidence is 90 degrees. The glass has refraction index n2= 1,5 and thickness 2 cm. Its front side is convex with a convergence radius,R, of 11 cm. The back side is plane. Whats...

Summary:: If you send a laser beam through a prism, can you measure any shift in wavelength at the other side of it? This sounds like a high school experiment and the concept is simple. I feel the laser should emerge monochromatic and at the same wavelength it went in. Do you get this result...

Hello everyone, I don't know which laserdiode and lens system should I choose for my Project. It is all about AFM Microscopy with a cantilever ( Length= 450 um, width = 50 um and thickness= 2um). So as you see it is not a small cantilever. As far as I Know, the larger the cantilever is, a larger...

I haven't been able to pinpoint a definition of "angular divergence" of a laser so by pure intuition I assumed it would be something like ##\theta=\frac{2R}{D}## and with that I have that the radius of the lase beam is ##R=\frac{D\theta}{2}=90\cdot 5 \cdot 10^{-6} m=450\ \mu m## so...

How does powder behave under centrifugal force? Let's imagine that we put the powder in a box and start rotating it. How can I understand how the powder will behave? Will it be flat and stick to the outer side of the box or...?

Here it is specified that optimum operating temp for industrial C02 laser is within the range 59 °F to 77 °F. This is what is generally specified online, but it leads to a number of questions; How is this measured? Does it refer to the whole unit, or the point of emission of the beam, or some...

Hello, I am trying to learn comsol but I couldn't find how to apply the pressure that changes respect to time and space. I have pressure function from articles that I read but couldn't implemented on comsol, and in most studies people make the simulation with Abaqus software so I am not sure...

I utilized an Ultrashort Pulse Calculator on a website (https://www.rp-photonics.com/ultrashort_pulses.html) and got the bandwidth of 9.39nm with the specifications listed above. Then divided the wavelength by the bandwidth, and it came out 85(optical cycles). However, I am not sure if it is...

Would you be able to help me figure out the equation to be used at both lenses to get the final light sheet?

So (wildly simplistically) lasers work by photons being reflected between mirrors gaining energy on each trip through the medium until they break through the mirror on the output end. How many trips does that typically result in? 10s, millions? And thus the total distance is that count * the...

I want to set up exhaust to take up fumes for my cnc laser. Do I need to cmpletely enclose it, or can I just put some suction near the cutting head? Thanks so much Joe

I was thinking of an improvement to the "traditional" diy cnc laser cutter that might entail some extra travel for the laser and/or additional (stationary) mirrors. Is there some way to calculate how this will affect output power? Many thanks in advance Joe

Hello! I am trying to measure the gaussian profile of a laser beam, which is supposed to be T00. The profile shown in the specifications looks very Gaussian, and the laser is brand new. I am using this camera and I am using 2 of these wedges to guide the laser beam into the camera (mainly to...

Hello, Does anyone own a laser cutter and knows how to operate it with some level of experience? I have some questions... Thanks!

Hi, all I have a circuit where the base transistor (PN2222a) leg is plugged into the pin 9 of the Arduino. When I power everything up and send the signal from the Arduino to the transistor base leg, the laser diode doesn’t light up, but my design strictly follows Complete Tech Guide to Laser...

I had an argument with someone about laser weapons and he/she said "haven’t you listened about noise cancelation technology ? the light is electromagnetic wave as the sound is mechanical wave . The laser rays can be canceled the same way and even using the beam’s own energy ". there is any...

Hello! I am trying to understand the properties of a laser I am trying to lock to a cavity. I would like to adjust its wavelength in order to achieve the locking. I attached below a part of the properties that I am confused about (I emailed the company, too, but I haven't heard back yet). I...

Hello! I tried to find some papers about laser cooling in Penning traps, but all I could find were theoretical papers, no experimental ones. Has laser cooling been done in a Penning trap? And if no, why so? I assume that sending the lasers is more complicated than in a Paul trap, but there are...

Please help me understand why this is a concept that has not been studied? The laser sail is really the only info I can find in this area using a laser from a fixed source. Using liquid nitrogen to cool the mirrors and reflecting lasers off of them for propulsion. I'm a Doctor of Pharmaceutical...

When working with a pulsed laser (nitrogen), How can the fluorescence lifetime be longer than the pulse of the laser? Thanks for any explanations

Hi, I am reading paper that I have to give a quick presentation on. I want to calculate the average power and peak power of the laser used, a Ti:Saphire laser. I have the wavelength they are lasing at (450nm), the repetition rate 81Mhz and the pulse duration (pulse width) of 100fs. I have done...

Can a continuous wave laser weapon be converted to a Ultrashort Pulsed Laser like the one mentioned in this article?: https://www.forbes.com/sites/davidhambling/2021/03/11/us-army-develops-laser-machinegun-firing-light-bullets/?sh=6555843768a3 Israel is also developing laser weapon for...

First question: When shining a laser (##\lambda = 630nm##) through a 2D crystal, diffraction patterns are observed. Why? Possible reasons: 1. Atoms and the space between them act as diffraction gratings. 2. Bragg Diffraction, although in this case the pattern would be observed on the same...

I'm having trouble understanding stimulated emission and population inversion, and how they work together to make a laser work. I pretty much need this explained completely. 1. Spontaneous emission, they say, is when an atom absorbs and then later emits a photon. Isn't that just regular...

Hello, If I shine a red laser onto a white surface, I assume that: some of the red light will be nearly instantly reflected, some will be absorbed and converted into phonons and some will be absorbed and re-emitted. Is that correct? I know that my laser has this extremely narrow spectrum...

Hello Everyone! I read about the function of the ruby laser which made from ruby crystal and has three energy levels. There is radiationless transition to what so called metastable level and then the electrons there stimulated to transit to ground energy state. The question is: does this...

Hi. This is an idea which I just happened to think of, and I was curious if it would be at all feasible. Here's a quick sketch I drew: The two curved mirrors should have a laser attached on one end and a video camera attached on the other. The laser would be tilted very slightly above...

My question is the physics behind the LASER such as stimulated emission can be only explained by quantum mechanics only. We can represent LASER as coherent state in quantum mechanics only. Then how can we say LASER can be thought of a classical light source?

I have found the value for the full width at half maximum line profile width , I know the the density of the upper lasing state for the helium neon laser is 10^18 m−3, and I am assuming I have to use dN_2/dt = -A_21N_2, which I can turn into N_2(t)=N_2(t=0)exp(-A_21*t), and I have calculated...

I really enjoy learning strange facts and while i would never assume to be a "Smart" person i do have the power to ask. So with a plasma fusion reactor like the tokamak or any other they have a viewing window to see the plasma bound in the toroidal magnetic field so what would happen if you...

I have dismantled an old DVDRW drive and taken a 4-pin laser diode from it. After connecting it to two 2A batteries (red with positive, and blue with negative), the light beam is diverging, and the brightness is even dimmer than another laser diode that I got from a presentation pen. Also...

According to this link https://apps.dtic.mil/dtic/tr/fulltext/u2/a351472.pdf, HERMES III at Sandia National Labs can generate very large area gamma rays by converting the electron beam into bremsstrahlung radiations after hitting the tantalum target. As we can see in the isodose contours in the...

I read in the internet that the reason that two laser can't Interference because they most likely have difference phase. but electromagnetic wave are just change in the electromagnetic filed that goes up and down , so mathematically they may Interference little let say that the there is...

there is anything that have input of two laser and output one laser with a bit bigger radios or just stronger laser like a beam just the opposite instead of splitting one sources connect two sources

If we use a spear or gun with bullet, then we should aim lower than the position where we see the fish because due to refraction, the apparent position of the fish in the lake will be higher (nearer to the surface) than the actual position of the fish. But if we use a laser gun, I think we...

I saw the solution of the light propagates in cylinder.. so in every solution there is the first order Gaussain function (the slandered one) times another function which gives I think the separation, both of them gives the intensity separation.. So what does that mean?! is it as I draw on the...

I bought one of the lasers from quantumlaserpointer.com If I remove the cap I can see the two thin slits cut in it. If I hold the laser around 3ft from a surface it appears to show the refraction pattern. Is this actually working like the dual slit experiment and the laser photons are going...

I read in couple of articles, like this one: https://link.springer.com/content/pdf/10.1007/BF00324203.pdf that regions of fused silica surface can be ablated by laser... I have two questions: 1- Why does the ablation occur? 2- does the ablation happens when the laser waist point is under the...

I want to split a fat laser beam and interfere it with itself, kind of like this: The very obvious problem is that the wave peaks shown as black lines would be a whole lot closer together, so the interference fringes would be sub-microscopic. If a couple of glass wedges - oddly-shaped prisms...

This is an older idea of mine which I just remembered when reading the thread about using a light-bulb to make a laser. The concept is this: 1: Focus light from the sun into a point using a magnifying glass, which we know can burn things. 2: at the point of focus, place another lens which will...

so I was recently studying some ray optics and then suddenly a weird question came across my mind I just don't know if it's the correct thread to ask but let's continue anyway So the question is : suppose there is a spaceship traveling at light speed and someone fire a laser inside it what...

In my drawing you can see: A generic bulb covered by a mirrored hollow ball. The hollow ball has a small hole (1 mm diameter). So the complete light will go through this small hole. The lens will bundle the light in a very distant (100 km) focal point. I guess it might be hard to create such a...

I was trying to research about polarizing lasers for an experiment, and there were some things that were confusing? A website said, I was wondering if the polarization ratio was the same as the extinction ratio? Also, I was curious because I thought 100:1 would be a lot, and not much light...