18
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Can a very bright light attract an incoming laser guided weapon?
No. It might blind it but it would not attract it.
Laser guided weapons aren't just laser versions of heat-seeking weapons. You would modulate the targeting laser so that it could be differentiated ...
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7
votes
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How can I build a micrometer diameter laser beam from a common laser diode?
Why this is hard
One micron is on the border of what is theoretically possible. You cannot create a parallel ray at this scale. One micron is almost as small as the wavelength of the light you are ...
- 398
7
votes
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Alternatives to laser line?
A few points that don't fit into a comment but could help you:
Get a better laser source than a 4 \$ laser diode. "Better" means a laser with higher beam quality. When you look at a laser's ...
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7
votes
How much power does it take to supply a laser which delivers 100 watts?
The total electrical to optical power efficiency of a laser system is sometimes termed wall-plug efficiency. It is the ratio of
$$\eta = \frac{\text{optical output power}}{\text{consumed electrical ...
- 24.2k
5
votes
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Why laser cutting speed suddenly decrease when cutting sheets from 1 to 3mm thickness then stabilize?
To see why this graph can only have a hyperbolic shape, it can help to take a look at the energy balance of the laser cutting process with absorbed laser power $P_A$.
$$P_A = \underbrace{vtw}_{V_M}\...
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4
votes
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How does a laser printer write with light on the photosensitive drum?
You are apparently asking about the Xerographic process, such as used in original copy machines and now in laser printers.
The process works by charging up the surface of a cylinder (the drum) to a ...
- 11.4k
3
votes
What is best sensor & method to measure human height?
Hair is mostly transparent to ultrasonic, so this is still the reliable&convenient approach - any EM spectrum readouts (3D, video, laser) will be completely falsified by hair.
You just need a ...
- 6,115
3
votes
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Can I use an optical fiber to direct a laser cutter?
CO2 lasers cannot be coupled into standard silica-based fibres, because these fibres absorb light longer than 2.1um. You could use hollow silica fibres, but they are quite recently developed, so might ...
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3
votes
Why is making a white laser so difficult?
Its not hard- it bends the idea of what a laser is. Lasers have a single (or very narrow) wavelength of light emitted. There is no "white" wavelength- its just what your eye perceives from a (...
- 762
3
votes
Device that emits a safe beam of light - doesn't have to be visible (Like laser, but safer)
There are eye-safe lasers, both in the visible and IR. For your detection system, make sure you understand the power required for your target (receiver) to register a hit. Pretty much any ...
- 4,249
3
votes
How is digital image-data converted to a laser projection in laser printers?
I'll answer the questions in reverse order.
If the laser beam draws like a pencil, how is the laser guiding mirror that directs the laser beam onto the drum able to move so fast that a page is ...
- 10.9k
3
votes
Smallest possible elliptical hole
It's unlikely you'll be able to accomplish your goal. Lasers and high pressure water jets are not the tools for the smallest possible features.
Electrical Discharge Machining (EDM) is capable of ...
- 7,297
3
votes
How would I use a laser to cut a moving solid object?
However, usually lasers come as a point, which means that we'd have to make the laser head move in quite an exotic curve, which will slow down our cut rate.
The limiting factor is usually the cutting ...
- 10.9k
2
votes
How do I sense reflective tape such as on a spinning wheel?
The "laser device" you're looking for is called a Laser Tachometer, though other illumination sources will work. I have had good success with devices from Monarch Instruments. Specifically the ROS-P ...
- 2,145
2
votes
How to handle reflections when cutting metal with a laser?
I know this is an old question, but I'd like to expand on the general info alephzero stated.
In my research for building my own metal cutting CNC laser, I've found that it takes at least a 150 watt ...
- 221
2
votes
How can I build a micrometer diameter laser beam from a common laser diode?
If you have one convex and one concave lens, you can effectively make the laser beam smaller and more concentrated while still having a parallel ray. I believe it's called a galilean lens. It would ...
- 1,194
2
votes
FM transmission over laser
No, it is not possible to modulate the wavelength of a laser. The particular wavelength of light is determined by the amount of energy released when an excited electron drops to a lower orbit, which ...
- 7,761
2
votes
On construction of a triangular interferometer like LISA
If I'm understanding your question correctly, you are asking how you can build a functional laser interferometer.
That is a pretty complex topic and impossible to cover in detail in a single answer. ...
- 1,943
2
votes
Why are fine metal filters made of meshes?
Photo-lithography is expensive and is generally more useful in etching away some surface layer than drilling holes. Generally the light source doesn't actually remove material but selectively cures a ...
- 15.2k
2
votes
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How 2 lasers interacting causes a dot of light
The full letter is here:
https://www.nature.com/articles/nature25176
They have 4 lasers: an RGB beam (3 lasers) that provides colour and an invisible 405nm beam that traps the particle. The RGB beam ...
- 36
2
votes
Scalable alternatives to CNC router and laser cutter
You can certainly drive the cost down by injection moulding the plastic parts. It has a relatively high setup cost though. Acrylic can also be extruded. In both cases laser cutting is probably also ...
- 3,675
2
votes
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Calculating energy loss from laser when shining through a material
The equation you are looking for is
$$I(z) = (1-R) \cdot I_0 \cdot e^{-\alpha z}$$
where
$I(z)$: intensity of the laser beam after the distance $z$
$R$: reflectance of material
$I_0$: intensity ...
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2
votes
Calculating energy loss from laser when shining through a material
There are a number of things to deal with. The plexi has a reflectivity of around 4% per surface (see, e.g. this spec sheet , but minimal absorption. So pure loss is 8% (but will increase ...
- 4,249
2
votes
Accepted
Laser Power vs Efficiency
As I already mentioned in my comment, I would recommend to take a single laser source rather than five seperate laser sources, for multiple reasons:
The effort to align the beams of the five diodes ...
- 1,923
2
votes
Accepted
Laser saturation and laser saturation intensity
The saturation effect of the laser-active medium occurs especially in the case of optically pumped lasers. To understand what is happening here, we need to look a bit deeper into the mechanisms behind ...
- 1,923
2
votes
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How solid state lasers work?
If a photon hits an already excited atom, it can make it to de-excite and also eject another photon. That is induced emission. This new photon will have the same properties (phase, direction) than the ...
- 2,369
2
votes
Accepted
What Rubber is Best for Laser Cut McKibbens PAMs?
There are silicone specific adhesives, as silicone does not adhere well to any other material. Appropriately, there are rubber adhesives for genuine rubber as well. The method you describe is going to ...
- 7,297
2
votes
What is the highest repetition rate achieved for pulsed Terawatt and Petawatt-order lasers?
In Europe, the SYLOS3 laser system boasts one of the highest repetition rates 1kHz for high intensity lasers 15[TW] (December 2020) (see Optics.)
SYLOS is a part of the ELI-ALPS European Facility in ...
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1
vote
Can you focus a 300W LED to a small area?
If you just want a highly focussed light source, consider a halogen car headlight bulb. The bulb itself contains a parabolic reflector to give a focussed beam. The Fresnel lens in the front of the ...
- 12.6k
1
vote
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Laser engravers and focal points
... the laser itself is fixed in position and mirrors are used to redirect the laser to the material.
Yes. This system is called "flying optics". The delicate laser is fixed in position and only the ...
- 10.9k
Only top scored, non community-wiki answers of a minimum length are eligible