Help Needed.

[NuGenZ3D]

Hello, I'm a little new to lasers, but I'd like to build my own; Preferably I'd like something that a, somewhat, mentally challenged monkey could build without much hassle and could teach (the mentally incapacitated monkey) some of the basic mechanics, techniques, etc. of lasers. Please put any products, videos, designs and helpful information in this thread, Thank you all.

 

[Lifetime17]

hi,
First please go to the welcome section and introduce your self so we can get to know you better. the folks here would be more willing to help. In your avatar tell us what part of the country you live in .
Rich

 

[Cyparagon]

Please read the stickies. Your information is there. They are mere pixels away from where you've posted this thread.

 

[Immo1282]

Stickies are very helpful for first builds - You're not going to get the best out of the forums by asking to be spoon-fed unfortunately. Same applies at university which you'll soon be off to as you mentioned in your introduction - You're expected to read around the topic and learn more than you're taught directly. Go and read the stickies & search for threads on things you want to learn about.

Despite that I just said we won't spoon-feed you, here's a few things I'll share anyway.

In terms of a first build, don't try to take on too much. Look into either getting a custom heatsink for a known host from one of the forum members (or using one of the hosts from SurvivalLasers for example).

Forum favourite supplier of all things diodes/drivers/modules etc is Jordan at DTR's Laser Shop. His prices are really good and shipping won't be too expensive for you as he is based near St. Louis MO.

Key things to remember when dealing with laser diodes/modules is that they are fairly fragile. Laser Diodes do not respond well to static discharge, and must be driven by a current-regulated power supply. The diode drivers that are mentioned on this forum are generally all designed to provide a constant current. Laser diodes have a negative temperature coefficient - which means that the hotter they run, the more current they will draw - thus running an LD on a voltage-regulated power supply will likely kill it.

 

[Lifetime17]

Hi,
Great your reading info here much to learn. Hope it goes well for you.

Rich

 

[NuGenZ3D]

Stickies are very helpful for first builds - You're not going to get the best out of the forums by asking to be spoon-fed unfortunately. Same applies at university which you'll soon be off to as you mentioned in your introduction - You're expected to read around the topic and learn more than you're taught directly. Go and read the stickies & search for threads on things you want to learn about.

Despite that I just said we won't spoon-feed you, here's a few things I'll share anyway.

In terms of a first build, don't try to take on too much. Look into either getting a custom heatsink for a known host from one of the forum members (or using one of the hosts from SurvivalLasers for example).

Forum favourite supplier of all things diodes/drivers/modules etc is Jordan at DTR's Laser Shop. His prices are really good and shipping won't be too expensive for you as he is based near St. Louis MO.

Key things to remember when dealing with laser diodes/modules is that they are fairly fragile. Laser Diodes do not respond well to static discharge, and must be driven by a current-regulated power supply. The diode drivers that are mentioned on this forum are generally all designed to provide a constant current. Laser diodes have a negative temperature coefficient - which means that the hotter they run, the more current they will draw - thus running an LD on a voltage-regulated power supply will likely kill it.

Thank you, didn’t mean to come off as “needy”, I just didn’t really know where to start in this great lexicon of lasers. However, just by visiting the DTR shop I’ve expanded a little bit of my knowledge of the quality of products.

 

[Immo1282]

Thank you, didn’t mean to come off as “needy”, I just didn’t really know where to start in this great lexicon of lasers. However, just by visiting the DTR shop I’ve expanded a little bit of my knowledge of the quality of products.

No problem - I was a bit grumpy earlier but have had some lunch since - so probably won't lash out as much

What sort of thing were you thinking for a first build? i.e. What do you want the final thing to be like - Powerful enough to burn, colour of the beam etc.

Different technologies have different strengths - i.e. if you wanted a laser that's beam is more visible, but you're not so concerned about burning things then go for a green (520nm for Direct-diode, 532nm DPSS). If you don't care about beam specs (divergence and dot shape) but want raw power, go for a high-power 445nm Blue diode.

There's never been a better time to build a diode laser as high power diodes are fairly affordable, and previously "exotic" wavelengths have reasonably affordable avaliable manufacturers.

Edit: Absolutely read RedCowboy's post which is below mine before you do anything!

 

[RedCowboy]

Here's the single most important thing you will need to understand before starting : ((( LASER SAFETY )))

Monkey NO point laser at testicles. No....not that, you will understand about that rather quickly on your own.

You will need laser safety glasses that attenuate the wavelength you are working with to protect your eyes.

Also please lase safely as to not injure anyone else and know your local laws.

You can start here > https://laserpointerforums.com/forums/laser-safety-info.75/

 

[paul1598419]

DTR's Laser site is a good way to see what is available, but not everything that is available. If you want to get into the nuts and bolts of lasers try visiting Sam Goldwasser's Sam's Laser FAQs. There is a great deal of information there on all types of lasers and is a great way to learn some of the physics involved in laser technology.

 

[NuGenZ3D]

No problem - I was a bit grumpy earlier but have had some lunch since - so probably won't lash out as much

What sort of thing were you thinking for a first build? i.e. What do you want the final thing to be like - Powerful enough to burn, colour of the beam etc.

Different technologies have different strengths - i.e. if you wanted a laser that's beam is more visible, but you're not so concerned about burning things then go for a green (520nm for Direct-diode, 532nm DPSS). If you don't care about beam specs (divergence and dot shape) but want raw power, go for a high-power 445nm Blue diode.

There's never been a better time to build a diode laser as high power diodes are fairly affordable, and previously "exotic" wavelengths have reasonably affordable avaliable manufacturers.

Edit: Absolutely read RedCowboy's post which is below mine before you do anything!

Firstly, thank you for your concern, I’m interested in color (colour for you) profile, single mode, low divergence and decent wattage. I don’t really care for high powered burners because I don’t really understand the safety hazards of such high powered beams. Exotic diodes is what I’m hoping to work up to, like cyan (480-490nm?) and yellow (570-590nm?), however I think until I get the basics of lasers down, I will stick to probably red at 650nm as it appears to be the cheapest, In contrast to yellow, which in fully built modules can cost hundreds of dollar.

Just read about 1W laser buring through someone’s retina, I don’t think I will be using one of those anytime soon.

 

[Immo1282]

Just read about 1W laser buring through someone’s retina, I don’t think I will be using one of those anytime soon.

It doesn't take anywhere near 1W to burn a sizeable hole in a retina with a direct beam hit - but the best way to avoid things like these is to wear proper laser safety goggles for the wavelength that you're using. The main hazard with high power lasers (especially when "burning") is the intensity of the light even reflected off surfaces - exacerbated when the beam is focused to a small dot.

650nm can be very cheap, but kind of boring It's the same red as in any cat toy laser. DPSS will tend towards having better divergence, but very cheap DPSS lasers can mode-hop which is not great. Also with DPSS, be mindful of stray IR light from the pump diode (invisible IR wavelengths, that won't be safely blocked by laser goggles designed for green wavelengths.

I have a 1W 445nm from Sanwu and mostly use it outdoors because the risk to my vision is lower. I live in a flat with white-painted walls and I'm nervous at accidentally looking at the spot on a wall. A dark tree, or cliff that's 20-50m away is far less hazardous.

 

[NuGenZ3D]

It doesn't take anywhere near 1W to burn a sizeable hole in a retina with a direct beam hit - but the best way to avoid things like these is to wear proper laser safety goggles for the wavelength that you're using. The main hazard with high power lasers (especially when "burning") is the intensity of the light even reflected off surfaces - exacerbated when the beam is focused to a small dot.

650nm can be very cheap, but kind of boring It's the same red as in any cat toy laser. DPSS will tend towards having better divergence, but very cheap DPSS lasers can mode-hop which is not great. Also with DPSS, be mindful of stray IR light from the pump diode (invisible IR wavelengths, that won't be safely blocked by laser goggles designed for green wavelengths.

I have a 1W 445nm from Sanwu and mostly use it outdoors because the risk to my vision is lower. I live in a flat with white-painted walls and I'm nervous at accidentally looking at the spot on a wall. A dark tree, or cliff that's 20-50m away is far less hazardous.

What would be the safest yet most visable milliwattage to work with? Should I also try 630nm and IR filter? I have heard that they are a more intense red and I’ve seen people “fix” their lasers leaking IR light.

 

[Immo1282]

No need for an IR filter on a direct-diode laser. Unfiltered DPSS lasers emit IR on the side of their desired output due to their design (they use an IR pump diode, which pumps two crystals in line that change the output wavelength. I can't really comment much on reds as I've not really seen a 635 against a 650 in person.

What would be the safest yet most visable milliwattage to work with?

This is sort of subjective. If you are not wearing any safety glasses, or intend on using the laser around other people, stick to the lowest possible power (<1mw). Highly visible lasers imply high levels of power which requires the correct protection.

 

[Anthony P]

I have homebuilt many gas lasers but only recently started into diode builds. My first diode project was very simple and inexpensive. An LM317 as current regulator and Osram 450 diode from Mouser Electronics. At least for me, this was a good way to get my feet wet with diodes.

 

[paul1598419]

It doesn't take anywhere near 1W to burn a sizeable hole in a retina with a direct beam hit - but the best way to avoid things like these is to wear proper laser safety goggles for the wavelength that you're using. The main hazard with high power lasers (especially when "burning") is the intensity of the light even reflected off surfaces - exacerbated when the beam is focused to a small dot.

This is not entirely correct. When you focus a laser to a small spot several inches away the far field beam will be spread out to a much larger spot. Therefore, a reflected beam from this would not be a high density power beam, but a diverged beam that is far less hazardous. Usually when one is burning surfaces close up they are not reflective surfaces and will not cause any part of the beam to reach your eyes. The only real problem arises when you are trying to burn through metal which can reflect the beam, or at least part of it, still collimated back to your eyes. A beam seen on a nonreflective surface such as a wall in a room is no more dangerous than any other point source of light. This is because the light can be seen from anywhere in the room, and as such decreases as the inverse square of the distance you are away from it.

It is collimated beams that cause retinal burns, not the uncollimated spot or the beam as can be seen because of particles in the air. If you try to see the beam from a laser going through a vacuum, you will not be able no matter how high the power is.

 

[NuGenZ3D]

This is not entirely correct. When you focus a laser to a small spot several inches away the far field beam will be spread out to a much larger spot. Therefore, a reflected beam from this would not be a high density power beam, but a diverged beam that is far less hazardous. Usually when one is burning surfaces close up they are not reflective surfaces and will not cause any part of the beam to reach your eyes. The only real problem arises when you are trying to burn through metal which can reflect the beam, or at least part of it, still collimated back to your eyes. A beam seen on a nonreflective surface such as a wall in a room is no more dangerous than any other point source of light. This is because the light can be seen from anywhere in the room, and as such decreases as the inverse square of the distance you are away from it.

It is collimated beams that cause retinal burns, not the uncollimated spot or the beam as can be seen because of particles in the air. If you try to see the beam from a laser going through a vacuum, you will not be able no matter how high the power is.

Amazing, So collimated photons directly hitting the retina is what does it in.