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Custom device request (5-10mW pulse infrared)

Echemythia

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Hi!
I'd like to commission someone in this community to build me a device.
I'm looking for something quite weak by your standards.
The minimum I'm looking for is a 5mW pulsed 660nm (maybe, currently undecided) handheld unit that can switch from a constant beam to a pulse every 500ms (also undecided). When I hear back from the someone about what's possible and what it costs I will solidify these specifications.
I don't know much about lasers but I know a tiny bit.
A few more questions:
1. Is there a possibility of changing the timing on the pulse to an additional setting (1sec)? (So, perhaps a three-way sliding toggle?)
2. Is there a possibility this could be done with LEDs rather than LDs?
2a. If so, could three or four different nm LEDs be crammed into the end of a handheld unit, with the same specifications?
3. Is there a way that the wattage could have another setting as well? Low-level and "high"... maybe... 10mW? Lol!
4. Also, how finely tuned can the ms of the pulse be?
I'm looking for something sturdy and reliable, that could stand daily use for years to come.
If I'm satisfied with the product, there is a very good possibility I will both be requesting more devices from you in the future AND giving your credentials to colleagues of mine who may be interested in ordering something similar to what I'm looking for. Just so you know what's in it for you!
If you'd like to help me with this, please give me an estimate for it and let me know what the timeframe would be. You can PM me the estimate.
Thank you in advance!!!
 
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diachi

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This will be used in a medical setting?
 

brendon7358

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Might be easier if you said what you were trying to do with it.
 

paul1598419

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A 0.5 Hz laser pulses every 2 seconds. I believe you were looking for a 2 Hz laser that pulses twice a second. You needn't add the /1 sec after Hz. That would be used in the antiquated CPS, cycles per second, designation.
 

Echemythia

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Yes! Thank you for the clarification! I will stick with saying 500ms and 1 sec.
I am now in the market for TWO of these same lasers, possibly three. I will know if I want a third one by Wednesday.
Any takers?
 
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Alaskan

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Aside from the diode and host a control circuit board can fit into, you just need a TTL laser diode driver and a timing source, perhaps a 555 timer chip would do with a switch to change the rate. I know of some members who could do that, let's see if they speak up.
 

Echemythia

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Very cool, thanks.
How about the kind of casing that would be used? Can some LEDs fit into the tip of it?
Sorry - I hope it's not absurd to ask you laser-builders to build something with LEDs, lol.
But for photobiomodulation having a broader range of frequencies has advantages. Just a thought!
Otherwise we can continue on with 660nm!
 

Alaskan

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LED's would work without the constant current driver a laser diode should have, would be less expensive and can driven right off a 555 timer with a single transistor connected to it to increase the current needed for the LED's, as the timer won't put out much power itself. You can have what ever you need built by some members, how many LED's do you want in it and which model of LED?

The benefit of using a laser diode with the correct optics for the application is you can focus more power into a smaller point output, but if too much, of course, you could burn yourself.
 

WizardG

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If you wanna get fancy I could use an arduino compatible microcontroller as the heart of the thing. Control many outputs that way with millisecond control of the timing of all of them. The timing and wavelength(s) as well as output power would be controllable through a laptop or (for a few extra bux) a wireless remote for maximum flexibility. Something like that would be a good way to find out what's really needed. Then you could burn the programming into as many of the microcontrollers as you like and you could go into production. A prototype like this could pretty easily be stuffed into any flashlight host with a fat handle. Using LEDs something like this could be put together for ~$40 parts cost, batteries included.
 

Snecho

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If you wanna get fancy I could use an arduino compatible microcontroller as the heart of the thing. Control many outputs that way with millisecond control of the timing of all of them. The timing and wavelength(s) as well as output power would be controllable through a laptop or (for a few extra bux) a wireless remote for maximum flexibility. Something like that would be a good way to find out what's really needed. Then you could burn the programming into as many of the microcontrollers as you like and you could go into production. A prototype like this could pretty easily be stuffed into any flashlight host with a fat handle. Using LEDs something like this could be put together for ~$40 parts cost, batteries included.
Which Arduino were you thinking? Arduino nano?
 

WizardG

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A nano would probably be the easiest thing to build the prototype with. After that just program the 328s on your own custom boards for the most compact unit possible.
 

hwang21

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Depending on what kind of photobiomodulation you are trying to achieve, you may be better off with a LED/laser of 808nm, 980nm, etc. farther into the NIR spectrum. 660nm is fine if you're just trying to take surface measurements like heart rate, but for deeper penetration into the skin you are going to need longer wavelengths. Also, usually LED's are used for skin treatments/measurements over lasers since they are more easily diffused into a broader treatment area. If you are targeting something specific like a hair follicle, then lasers would make more sense
 

Echemythia

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YES! The laser-people assemble!!! You guys rock. :cool:

Depending on what kind of photobiomodulation you are trying to achieve, you may be better off with a LED/laser of 808nm, 980nm, etc. farther into the NIR spectrum. 660nm is fine if you're just trying to take surface measurements like heart rate, but for deeper penetration into the skin you are going to need longer wavelengths. Also, usually LED's are used for skin treatments/measurements over lasers since they are more easily diffused into a broader treatment area. If you are targeting something specific like a hair follicle, then lasers would make more sense
To tell you the truth I currently use a small, 5mW 635nm with great results. And yes, there's good reason to have focus and good reason to have a spread as well. I wonder, could a laser tip be added to only allow the LED light out through a small hole, even though there's more than one LED in there? I'm aware of the "showerhead" type LED/laser units on the market and I think all I'm interested in is a small point of light. To be more specific, I have in mind 605nm, 655nm, 715nm, and 835nm - if possible. Could one LED each of those be cranked up in wattage to actually deliver noticeable heat? I'm thinking at least 25W or more? Am I correct in thinking that LEDs require more wattage for the same kind of brightness you'd receive by putting lower wattage through an LD?

For a laser unit, is there a way to switch it from 5mW to 10mW in the same unit or does that require something unweildy?
Are the diodes listed above even available? If we can't get really close to those wavelengths (605, 655, 715, 835) with a laser then it makes me want to go with an LED unit because there's more of a spread to their emission spectra.

If you want to know where I'm getting these numbers from search "Re-evaluation of the near infrared spectra of mitochondrial cytochrome c oxidase: Implications for non invasive in vivo monitoring of tissues" in Google Scholar. I haven't posted enough to post a link yet or I'd post the link.

If possible - as it stands right now, what I'm looking for is a 5-10mW (switchable power?) 835nm pulse (500ms/1s/constant) handheld laser unit. If these can be replicated easily enough, I'd like two or three of them. I'm happy to compensate you for materials and shipping before they are built, and then pay you for labor after they are received. If you are interested in building these, please private message me.

A nano would probably be the easiest thing to build the prototype with. After that just program the 328s on your own custom boards for the most compact unit possible.
If someone is actually willing to come up with plans for a programmable unit like this, I would most certainly be interested in working out the details with you and purchasing one. I certainly have ideas about how I'd like something like this done.

Thanks to all of you for thinking this all through with me. I didn't have set plans when I came here, but I wanted to know if something in the ballpark of what I wanted could be done. Very happy already.
 
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WizardG

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Could one LED each of those be cranked up in wattage to actually deliver noticeable heat? I'm thinking at least 25W or more?
I presume you're talking about an entirely different unit here. 25 watts is entirely doable with LEDs but not usually with a single LED.

If someone is actually willing to come up with plans for a programmable unit like this .......
Programming for the microcontroller is the easiest part of that build.
 




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