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ArcticMyst Security by Avery

Heat generated by a laser beam

Joined
Mar 20, 2014
Messages
50
Points
8
So, let's say I turn on my 200 mW green laser and I focus it. If I put some black paper into the focus of the beam, the paper will burn. There's nothing new in this.
But what's the actual heat generated by the beam over the piece of paper? Is there a way to calculate it?
 





Joined
Mar 20, 2014
Messages
50
Points
8
Why you don't test with a thermometer and black paint? You can buy a cheap thermometer from ebay Dallas DS18B20 18B20 to 92 Thermometer Temperature Sensor Original | eBay and connect it to arduino or other board. This going to read 125 degrees how much

Well, a thermometer will measure temperature, not heat. They're different things.
I'm not sure it is correct, but since
Power = Energy / Time, then
Energy = Power * Time, which means that
0.2 (W) * x (seconds) = y (J), where x is the time I keep the laser turned on and y is the heat in Joules. If from this I want to get the temperature, since
Heat = (Specific Heat) * Mass * (Temperature Variation), then
Temperature Variation = Heat / ((Specific Heat) * Mass).
I'm just not sure if this is correct.
 

upaa27

0
Joined
Jul 10, 2013
Messages
618
Points
28
Not sure what you mean exact,y but a laser beam has no definitive "heat". It is just energy and whatever material it hits is heated depending on how much it absorbs
 
Joined
Sep 12, 2007
Messages
9,399
Points
113
By "heat generated" do you mean "energy transferred to the target"?

(Beam power in watts) * (exposure duration in seconds) * (absorption percentage) = (energy in joules)
 
Joined
Mar 20, 2014
Messages
50
Points
8
By "heat generated" do you mean "energy transferred to the target"?

(Beam power in watts) * (exposure duration in seconds) * (absorption percentage) = (energy in joules)

Yes, and I think this answers my question. Thank you.
 




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