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ArcticMyst Security by Avery
Help with IR laser driver
- Thread starter Shreyas
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NKO29
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How do u use a laser diode as a heating element? Anyways 1W wont heat that much... Not to mention it would be extremely dangerous!
I currently have 1W and 2W IR lasers. Will 2W be enough? i need maximum temperature of 95 degree Celsuis.
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what are you trying to heat ? Lasers wouldn't be the best option for a heating element
I am trying to heat a small quantity of water solution. Its not more than 5 micro liter.
Speedy78
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Might be able to put the water in a container of some sort and heat the outside of it. You can probably find a driver on ebay.
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Heating element?
Sigurthr
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Water is mostly transparent to the wavelengths that IR diodes emit, the result of which is that the water will not be heated much, if any at all, by irradiation. You need Far Infrared in order to heat water.
Did you purchase these diodes specifically for this purpose or did you have them already? I'm afraid you've wasted your money on potentially expensive and certainly exceptionally dangerous laser diodes.
I have a 15W far infrared laser and tested its ability to heat water and was very surprised at how far off from theoretical it performed. To heat one milliliter (ml) of water one degree Celsius it takes one Watt to do it in one second. So, 15W should raise the temp of 1ml of water by 15degC in 1sec. Unfortunately, water reflects some incident radiation due to refraction. Since I don't have a crucible made of GaAs or ZnSe which are the only materials transparent to Far IR I had to use an inefficient angle of incidence which only enhanced the reflective properties of the surface of water. I was only able to measure an 8degC increase in water temperature in 10ml of water after 10sec of irradiation; 8W of energy input. Additionally, the reflected laser beam caused local heating in the glass test tube resulting in thermal cracking and skewed results in subsequent tests.
You're better off heating the sample with nichrome wire; it is electrically 100% efficient, safe, affordable, and fool-proof.
Did you purchase these diodes specifically for this purpose or did you have them already? I'm afraid you've wasted your money on potentially expensive and certainly exceptionally dangerous laser diodes.
I have a 15W far infrared laser and tested its ability to heat water and was very surprised at how far off from theoretical it performed. To heat one milliliter (ml) of water one degree Celsius it takes one Watt to do it in one second. So, 15W should raise the temp of 1ml of water by 15degC in 1sec. Unfortunately, water reflects some incident radiation due to refraction. Since I don't have a crucible made of GaAs or ZnSe which are the only materials transparent to Far IR I had to use an inefficient angle of incidence which only enhanced the reflective properties of the surface of water. I was only able to measure an 8degC increase in water temperature in 10ml of water after 10sec of irradiation; 8W of energy input. Additionally, the reflected laser beam caused local heating in the glass test tube resulting in thermal cracking and skewed results in subsequent tests.
You're better off heating the sample with nichrome wire; it is electrically 100% efficient, safe, affordable, and fool-proof.
Last edited:
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I was just going to recommend a power resistor and dump it in the water XD
