Questions tagged [lasers]
Questions related to lasers, laser-based systems or devices, and their applications.
61
questions
0
votes
0answers
15 views
How can I visualize the phenomenon of Bound State in Continuum?
I am doing my Masters Thesis on Bound States in Continuum (BIC) and I am finding it difficult to visualize the concept. Is it possible to observe the phenomenon through an FDTD simulation? It is also ...
2
votes
0answers
39 views
Comparison of beam divergence between laser diode and DPSS laser
I'm currently comparing a pulsed laser diode and a pulsed DPSS laser. For the DPSS laser, the beam divergence is listed as "beam divergence (80% of total energy): $<4 \text{mr}$". The ...
2
votes
1answer
432 views
How much power does it take to supply a laser which delivers 100 watts? [closed]
To enable the functioning of a laser which delivers--on average--100 watts of energy in its beam, how much power does it take?
(Does the 2nd law of thermodynamics dictate that the average power ...
4
votes
1answer
445 views
Alternatives to laser line?
I'm trying to project a very thin line at a low angle over some surface defects (peaks and troughs). The scale is ~20mm square, but the defects can be sub-mm (0.2 - 1.0mm).
I am currently using a line ...
2
votes
2answers
68 views
Using phone screen as a barcode
I have this extremely minor problem where my gym is 4 blocks away, and I'd like to go over with nothing but my phone. Unfortunately, I have to bring a card with me for them to scan with a barcode ...
1
vote
0answers
26 views
what does it mean to unfold a resonator
A way to find the modes propagating in a resonator of length $L$ is to write the field as $E(x,y,z)e^{i \omega t}$ and calculate $E(x,y,z)$ inside an equivalent periodic lens structure. Then imposing ...
1
vote
1answer
37 views
How would I use a laser to cut a moving solid object?
Using a laser to cut sections out of a small moving solid has been suggested for a manufacturing problem. However, usually lasers come as a point, which means that we'd have to make the laser head ...
2
votes
1answer
67 views
Why laser cutting speed suddenly decrease when cutting sheets from 1 to 3mm thickness then stabilize?
Please to understand what I mean, see the picture below :
I don't understand why it is not a linear curve (or almost), because at first sight it should be no ?
If you need 10 sec to cut a length of ...
2
votes
1answer
52 views
What is the highest repetition rate achieved for pulsed Terawatt and Petawatt-order lasers?
What is the highest repetition rate achieved for pulsed Terawatt and Petawatt-order lasers?
0
votes
1answer
40 views
What Rubber is Best for Laser Cut McKibbens PAMs?
I'm a layman engineer who's decided to take another step forward in my research and work with McKibbens Pneumatic Artificial Muscles. I’m new to creating custom rubber components and laser cutting, so ...
1
vote
1answer
58 views
Best method of bouncing laser off series of mirrors
I'm preparing to add a DIY laser system with the beam bouncing from the module at the top of the stairs and then bouncing off a series of mirrors down the stairs to an LDR. My question is essentially ...
0
votes
0answers
18 views
How do I detect laser point?
I know military uses laser designators and they can be visible by their bombs or missiles from really long range. My question is how could I do such laser point tracking device? Lets say I point laser ...
1
vote
0answers
17 views
Emerging beam from PPLN waveguide not behaving well through optics
We have a pump laser beam that is coming out of a single mode fiber and butt coupled into a PPLN waveguide crystal. We are capturing the beam at the output of the crystal with the focusing lens in an ...
0
votes
2answers
49 views
What power lasers can be used to heat fabrics to 70 degree Celsius?
For a project that I was building I wanted to heat fabrics to 70 degree Celsius using lasers.
Since fabric is a very wide term for now I was looking to draw heat patterns on 100% cotton T-shirt and ...
2
votes
1answer
64 views
How solid state lasers work?
In solid state lasers a light source pumps the medium, which is a crystal. A crystal is excited and emits infrared light, until then everything is clear.
What I want to know: after excitement, what ...
3
votes
1answer
69 views
What are some examples of laser-based additive manufacturing techniques?
I'm trying to research additive (or 'bottom-up') fabrication techniques that rely on lasers or other advanced photonic systems. So far, the most prevalent technique I've come across is two-photon ...
1
vote
1answer
56 views
Laser efficiency, what is this term?
I'm studying the laser input-output power relation. In particular I'm studying the laser slope efficiency $\eta_s$ ($\eta_s=\frac {dp_{out}} {dp_{in}})$.
However, my textbook tells that $\eta_s$ can ...
1
vote
1answer
767 views
Laser saturation and laser saturation intensity
Can someone explain what is laser saturation and laser saturation intensity? I don't find a proper definition and it seems to me similar to steady state intensity.
1
vote
0answers
21 views
Is it possible to use a laser push a 100 micron diameter droplet of water through a fine mesh?
Context
I've had the thought of a printing device that uses a thin grid that has holes small enough to allow suspension of a water based ink above a sheet of paper using surface tension. I've ...
1
vote
1answer
117 views
Laser Power vs Efficiency
Is there some kind of graph or relation between laser power and efficiency. What I'm trying to find out is whether the efficiency of a laser decreases with increase in power or is it that there is no ...
2
votes
2answers
42 views
Smallest possible elliptical hole
I am trying to fabricate a very small elliptical nozzle; if possible, 10um x 20um. I am almost certain that this cannot be achieved with regular machining. Ideally, the material would be corrosion ...
-1
votes
1answer
79 views
How is digital image-data converted to a laser projection in laser printers?
By laser projection I mean the laser beam that is projected onto the photosensitive drum in the laser printer. The printer receives digital image data from a computer processes it and projects it onto ...
0
votes
2answers
66 views
Can you focus a 300W LED to a small area?
I want to focus a 300W LED into a small area, about 5mm in diameter, much like focusing the sun's rays with a fresnel lens.
I have to be like 2 meters away from the LED to focus the LED light with a ...
0
votes
1answer
32 views
Laser engravers and focal points
If I understand it correctly in a CO2 laser engraver/cutter the laser itself is fixed in position and mirrors are used to redirect the laser to the material.
Is there some mechanism used to keep the ...
0
votes
2answers
606 views
How do I measure the time taken for a laser to cut a metal?
I am a placement student and was given a project asking to measure the time taken for the laser to cut a metal and send it to Excel into a spreadsheet automatically. I am a computer science student ...
0
votes
0answers
24 views
How would measuring the number of photons on a finite number of pulses break coherence of a weak coherent laser source in COW QKD protocol
I' m trying to understand attacks on Quantum key distribution protocols. In the COW QKD protocol, pulses from Alice are passed through an asymmetric
coupler and a fraction 'T' of the photons are sent ...
1
vote
2answers
109 views
What's the difference between pulsed lasers and frequency combs?
Can you please explain the difference between high-energy pulsed lasers and frequency combs?
1
vote
1answer
581 views
Scalable alternatives to CNC router and laser cutter
I am doing calculations on costs for alternatives for manufacturing this children's toy I invented, a puzzle where letters in plastic fit into wood.
I have been using a CNC router to carve subtract ...
0
votes
2answers
149 views
Calculating energy loss from laser when shining through a material
When attempting to trap a particle in a laser beam i was able to achieve the effect.
Pretty cool but now when i put of piece of plexiglass that is 1/8” thick i can no longer achieve the effect. The ...
1
vote
1answer
130 views
Trapping a particle in a laser beam (optical tweezers)
So upon watching videos and reading articles i understand few things. For one when the laser beam is focused to a tight enough point when placing a material in there (people use crayola markers) it ...
3
votes
1answer
57 views
How 2 lasers interacting causes a dot of light
Take a loom at this diagram
You have probably heard of this before but im just curious what laser they are using to do this. They do t appear to be ionizing air. It seems the one laser is just for ...
-1
votes
1answer
99 views
Why is making a white laser so difficult? [closed]
There are red, green, and blue lasers out there but i can't find a white laser? how hard is to make one? Is it possible?
1
vote
4answers
78 views
Why are fine metal filters made of meshes?
Given that we have mechanisms of performing photolithography at 10nm, why are metal filters often meshes? Wouldn't it make a lot more sense to buy a single chunk of metal, and use the UV lasers to ...
1
vote
1answer
1k views
What is best sensor & method to measure human height?
My application needed to measure human height on a standing kiosk. I need to attach the sensor on kiosk ceiling type top. I used different kind of ultrasonic sensor for this purpose but nothing ...
0
votes
1answer
25 views
Suitable laser for Engraving
I have made a CNC machine from CD drive and want it to use for engraving purpose. which laser would be best for this job?
3
votes
1answer
61 views
Tea nitrogen laser debugging
I am making a tea nitrogen laser based off the rimstarorg youtube channel. I have a perfect setup as seen below
I use 11, 1kv diodes to convert my 7,500 volt lug on my neon sign transformer to DC. My ...
0
votes
1answer
73 views
Can I use an optical fiber to direct a laser cutter? [closed]
Specifically, a 100W CO2 laser. Are there any considerations other than the maximum power for a fiber?
1
vote
1answer
63 views
Are DVD laser diodes single transverse mode?
I am looking for a cheap source of low power single transverse mode laser diode in order to focus them to a very small point. I thought I would get that from a DVD drive but the pattern I see at the ...
1
vote
3answers
934 views
How can I build a micrometer diameter laser beam from a common laser diode?
In order to build a lighting system for a microscope (with a digital camera) I want to make a very small diameter laser beam (parallel, rather than convergent). If possible around 1 um diameter.
How ...
1
vote
0answers
24 views
Where could I find, or what is a material that could be used with 30 GHz pulsed DC current to produce 30 GHz pulses of light?
I need to produce pulses of light that turn on and off for equal intervals at 30 GHz. I know there are lasers that are capable of this frequency, so I need to know what materials they use to produce ...
0
votes
1answer
57 views
FM transmission over laser
Modulate a laser's wavelength? What are the inner workings of a laser, and is it possible to change the wavelength mechanically? Are there any lasers that can change wavelength?
0
votes
1answer
54 views
Device that emits a safe beam of light - doesn't have to be visible (Like laser, but safer)
I am looking for a light emitting device, which can produce a narrow and accurate beam, with a small "dot" size, for a significant distance (around the 100-150 meters) similar to that of a laser, but ...
1
vote
1answer
65 views
On construction of a triangular interferometer like LISA [closed]
I am planning to do a project in which I plan to mimic the LISA interferometer. For this I use the fabric material, Lycra to mimic space time and use spherical balls, forming a couple and connected to ...
1
vote
1answer
345 views
How the electronic circuit control laser diode? [closed]
I find this scheme here
1 - is data stream come from computer. This 'data' is an electric signal moudulated by the n°2
2 - this is the electronic circuit inside printer that
a) activates the corona ...
5
votes
1answer
708 views
How does a laser printer write with light on the photosensitive drum?
I want to understand how a laser printers laser writes on a photosensitive drum. I am trying to understand this process.
the photosensitive cylinder is illuminated by a laser beam that projects ...
-1
votes
1answer
170 views
Is it possible to adapt the design and principle of operation for a tunable microwave photonic notch filter to a visible light photonic notch filter?
I just read the 2015 excellent paper , "Tunable microwave photonic notch filter based on sliced broadband optical source".
Is it possible to downconvert a microwave photonic notch filter to a visible ...
0
votes
1answer
70 views
How is an digital coherent receiver able to achieve 100 Mhz line-scan rate for detecting coherent light in the presence of incoherent light?
Recently, I read an October 2006 IEEE JOURNAL OF LIGHTWAVE TECHNOLOGY, article titled, High-Sensitivity Detection of Narrowband Light in a More Intense Broadband Background Using Coherence ...
0
votes
2answers
312 views
How do I sense reflective tape such as on a spinning wheel?
I know that the frequency and rotational speed of a spinning shaft or wheel is measured using a device that senses a piece of reflective tape on one of the rotating components. I am thinking a laser ...
2
votes
2answers
382 views
How does the Michelson interferometer measure the self-coherence function of coherent light in an incoherent background?
How does the Michelson interferometer measure the self-coherence function of coherent light in an incoherent background? Detection of coherent light in an incoherent background (Coutinho et al., 1999) ...
2
votes
1answer
2k views
Is it possible to reduce the divergence of a red laser pointer beam from 40 degrees to 1 degree?
I would like to find out if it is possible to reduce the divergence of a red laser pointer beam from 40 degrees to 1 degree.
@Ruslan wrote on October 3 2013 that because the active zone of a ...