Please help me with this

[Fizz8]

Hi guys,

So I am new here. And new to lasers as well. I really don't know anything about it.

So I had a question...

I want to buy a laser or a beam I don't know what to call it. That you can actually see the laser itself through the air.. not just a point on the wall.

What I would like is a blue laser that reflects when used on prisms. And I actually want it to be SO safe. I mean not burning laser and not the one that damages the eyes.

would you guys please link me a laser like this? or at least its name.

I'd prefer blue.. but if there isn't such a thing, then I would go with green.

Thank you so much <3

 

[HydroSean]

If you can see the laser beam through the air it is most likely not safe for your eyes...

Here's what the FDA says about laser power and safety,

Hewett emphasizes the reason for the 5 mW limit. “A 5 mW laser aimed directly into the eye won’t cause damage instantaneously. A person’s reflexes to look away, blink, or make other involuntary movements are protective. But if you keep your eyes open and stare into a 5 mW beam, it will cause damage. A higher-powered laser gives you less time to look away before injury can occur, and as power increases, eye damage may happen in a microsecond, even when looking at a beam reflection.”

BTW green lasers and blue lasers are NOT as safe as red lasers are to your eyes.
Here's the link to the FDA's site where you can learn all about laser safety and educate yourself.
Illuminating the Hazards of Powerful Laser Products

 

[kuhny1]

Technically, there is no safe laser. Every laser is dangerous if you take a direct hit to the eye long enough.

To answered you question about a laser that doesn't burn, and the least dangerous but still be able to see the beam would be a 5mw green.

You will not find a 5mw blue ie. 445nm, its just not going to happen, the diode (what makes the light) has not been invented, yet. You can search it up, but most likely it will be underspeced. However, you could get a 5mw 405nm but they are also underspeced pretty often as well.

Underspeced = they say it's 5mw but it can be above it.

Not sure what you mean by it has to reflect off a prism, because I'm pretty sure all frequencies of light reflect off of them...

Just search 5mw green 532nm laser on ebay, or on Google for that matter.

The 532nm is the color green, it just helps narrow the search.

 

[10fenny]

Any visible wavelength you can see the beam with enough particulate in the air.. aka fog or haze machine.. I got a visible beam out of my 1.73mw HeNe laser.. but my apartment also looked like a snoop dog concert inside muhahaha. Good luck and be safe. Glasses/goggles

 

[Fizz8]

Thanks for your reply.
So what I understand now is that red lasers are safer than the others.
and thank you for the link <3

 

[Fizz8]

Technically, there is no safe laser. Every laser is dangerous if you take a direct hit to the eye long enough.

To answered you question about a laser that doesn't burn, and the least dangerous but still be able to see the beam would be a 5mw green.

You will not find a 5mw blue ie. 445nm, its just not going to happen, the diode (what makes the light) has not been invented, yet. You can search it up, but most likely it will be underspeced. However, you could get a 5mw 405nm but they are also underspeced pretty often as well.

Underspeced = they say it's 5mw but it can be above it.

Not sure what you mean by it has to reflect off a prism, because I'm pretty sure all frequencies of light reflect off of them...

Just search 5mw green 532nm laser on ebay, or on Google for that matter.

The 532nm is the color green, it just helps narrow the search.

what I am doing with prisms.. I want the laser to be reflected off of them and still point at another place.. not to vanish after reflecting.

and Thanks for your reply. <3

 

[Sta]

Re: GUIDE: Which company should I buy from?

Thanks for your reply.
So what I understand now is that red lasers are safer than the others.
and thank you for the link <3

No, they are not safer than the others. Safety has very little to do with wavelength (color) and a lot to do with power. You would do well to purchase a green laser.

 

[H2Oxide]

Re: GUIDE: Which company should I buy from?

No, they are not safer than the others. Safety has very little to do with wavelength (color) and a lot to do with power. You would do well to purchase a green laser.

Technically, blue light is more damaging to your eyes than red or green, but since you should wear eye protection when dealing with anything >5mw, it doesn't really matter here.

As for your question Fizz8, a laser that is visible in untreated air (i.e. air without fog or smoke) will absolutely not be safe to view without eye protection. However, fog machines are pretty cheap, and a little bit of fog will go a long way. Green lasers appear brighter with less power since our eyes pick up green light better than other colors, so if you absolutely must see the beam, and have it be eye-safe, buy a green laser and a fog machine.

As for prisms, any laser that you can see (i.e. not UV or IR) will not be terminated by a standard prism. However, there may be high losses depending on the quality of your prism, so if you plan to send the beam through multiple prisms be prepared for some power loss.

 

[Fizz8]

Re: GUIDE: Which company should I buy from?

Technically, blue light is more damaging to your eyes than red or green, but since you should wear eye protection when dealing with anything >5mw, it doesn't really matter here.

As for your question Fizz8, a laser that is visible in untreated air (i.e. air without fog or smoke) will absolutely not be safe to view without eye protection. However, fog machines are pretty cheap, and a little bit of fog will go a long way. Green lasers appear brighter with less power since our eyes pick up green light better than other colors, so if you absolutely must see the beam, and have it be eye-safe, buy a green laser and a fog machine.

As for prisms, any laser that you can see (i.e. not UV or IR) will not be terminated by a standard prism. However, there may be high losses depending on the quality of your prism, so if you plan to send the beam through multiple prisms be prepared for some power loss.

thanks for your help. Really appreciate it.

now as I heard from you guys all .. that in general.. beams are bad for your eyes.. then I think I will use a pointer ( not a visible beam ) just on the wall.

but the question is.. can this pointer be reflected off of prism? I might use one prism though not many.. In a small room.. I want that pointer to be reflected then to point at a certain point on the wall.


and REALLY appreciate your help guys <3

 

[diachi]

Re: GUIDE: Which company should I buy from?

thanks for your help. Really appreciate it.

now as I heard from you guys all .. that in general.. beams are bad for your eyes.. then I think I will use a pointer ( not a visible beam ) just on the wall.

but the question is.. can this pointer be reflected off of prism? I might use one prism though not many.. In a small room.. I want that pointer to be reflected then to point at a certain point on the wall.


and REALLY appreciate your help guys <3

Do you mean refracted through the prism? You'd use a mirror - not a prism - to reflect a beam. Although it can be done with a prism too, technically...

 

[H2Oxide]

Re: GUIDE: Which company should I buy from?

thanks for your help. Really appreciate it.

now as I heard from you guys all .. that in general.. beams are bad for your eyes.. then I think I will use a pointer ( not a visible beam ) just on the wall.

but the question is.. can this pointer be reflected off of prism? I might use one prism though not many.. In a small room.. I want that pointer to be reflected then to point at a certain point on the wall.


and REALLY appreciate your help guys <3

Like diachi said, you will want to use a mirror to reflect a beam, not a prism. A prism is much better suited for refraction (bending the beam) rather than reflection. My profile picture is a good illustration of refraction through a prism.

The color of the laser doesn't matter as long as you stay within the visible spectrum (purple, blue, green, yellow, orange, red), as prisms and mirrors are designed to have high transmission and reflectance respectively in the visible spectrum.

Would you mind elaborating a bit more on what you plan to do with the laser?

 

[diachi]

Re: GUIDE: Which company should I buy from?

Like diachi said, you will want to use a mirror to reflect a beam, not a prism. A prism is much better suited for refraction (bending the beam) rather than reflection.

The color of the laser doesn't matter as long as you stay within the visible spectrum (purple, blue, green, yellow, orange, red), as prisms and mirrors are designed to have high transmission and reflectance respectively in the visible spectrum.

Would you mind elaborating a bit more on what you plan to do with the laser?

Well ... cheap off the shelf prisms are usually just cheap glass... As long as you're still within the transmittance of what is usually just regular glass (Wider than just visible) they'll continue working. Surface reflections/transmittance may vary across the UV,VIS,NIR but it'll still work outside visible to some extent.

Same goes for typical broadband (silvered etc) mirrors - they'll work outside visible to a degree too - maybe just not as well.

But yes, some more info would be nice!

 

[H2Oxide]

Re: GUIDE: Which company should I buy from?

Well ... cheap off the shelf prisms are usually just cheap glass... As long as you're still within the transmittance of what is usually just regular glass (Wider than just visible) they'll continue working. Surface reflections/transmittance may vary across the UV,VIS,NIR but it'll still work outside visible to some extent.

Same goes for typical broadband (silvered etc) mirrors - they'll work outside visible to a degree too - maybe just not as well.

But yes, some more info would be nice!

I just didn't want to go into absorption/transmission spectra of different materials and overcomplicate things. While some prisms and mirrors may indeed work all the way from NUV to MIR, I think that OP wants to deal only with visible light.

 

[diachi]

Re: GUIDE: Which company should I buy from?

I just didn't want to go into absorption/transmission spectra of different materials and overcomplicate things. While some prisms and mirrors may indeed work all the way from NUV to MIR, I think that OP wants to deal only with visible light.

Oh yeah, I see what you're saying now - I thought you were meaning they won't work outside visible. Read that a little incorrectly, my bad! +rep...

 

[Fizz8]

Re: GUIDE: Which company should I buy from?

Like diachi said, you will want to use a mirror to reflect a beam, not a prism. A prism is much better suited for refraction (bending the beam) rather than reflection. My profile picture is a good illustration of refraction through a prism.

The color of the laser doesn't matter as long as you stay within the visible spectrum (purple, blue, green, yellow, orange, red), as prisms and mirrors are designed to have high transmission and reflectance respectively in the visible spectrum.

Would you mind elaborating a bit more on what you plan to do with the laser?

well ya.. I think if I explain what exactly I want to do.. It will be easier for you guys to help me <3

So I have a small room filled with writings on the wall..and I should have a ( beam , laser , pointer ) hanged on the wall and when I turn it on.. it just goes straight. like it will point on the floor.. I want to use a prism ( or anything that could reflect ) from the floor to a certain word on the wall.

my preferences :
1- blue color
2- not using mirrors if possible
3- not using safety glasses ( want a safe one )

so these are preferences.. but if its really hard to do.. then I don't mind crossing out some..

Thanks <3

 

[Fizz8]

Please guys try to use simple sentences xD.. English is my second language.. so I miss some ideas =(.