Laser suggestion for 360° laser with cone mirror

I need to project laser 360°(like laser levellers) with solid state build. so 45° mirror and motor build is not an option.

I have few questions in my mind.



I have two ideas as shown above. cone mirrors cost $150-$200 online but I'm intented to make it myself.

My question is what kind of laser to use. I prefer IR beacuse I want it to be invisible. But all the IR lasers I've seen or bought are not producing the beam shape suitable(i think) for this project.

I need >1W and mobile enough to use in my project. I think I Need low divergence and round beam(o-like?)

Invisible wavelenghts are not mandotory but my first choice.

And would using diffraction grading lens be a solution for diverted and uneven beam ?

Basicly I'm looking for a laser suitable with this build.

Thank You

One Watt of infrared invisible wavelength scanning 360 degrees? At first glance, this sounds really dangerous. A much, much lower power is advisable, like 10mW.

Can you share why it needs to be 1 Watt? Will this operate in the fog? Underwater? Or on a planet with a dense atmosphere of sulfuric acid?

Many of the things we discuss and build on this site are simple laser devices. As such, the stuff we build with is plentiful and low cost.

What you're describing is more specialized. You may have a hard time of it building something with parts from your garage. With that said, you may save more money, if you just go out and buy (used) one of the many HeNe or red laser survey and leveling devices already available in the market, today. The US market, anyway. Where are you on this planet? I invite you to modify your profile to tell us.

Your diffraction grating idea isn't bad. But remember, you may get more than two divisions of your beam. Some gratings discussed on this site split the beam into 10 or 20 divisions (depending on the width of your beam) As such, the output power of each beam will be 1/10th or 1/20th of the total output power. Not ideal.

I know it sounds much but when you calculate the area of illumination and the intensity it is lot less then solar intensity.(for distances >3 meters)

Device will operate mostly in room conditions and rarely outside. Purpose of the build is shining the laser 360° and getting the images with couple of ccd sensors in order to measure the distance in multiple spots at the same time.

In diffraction grating, does it have to be "divisions"? Can't we get a continuous circle shape or line?

in the diagram, diffraction gratings output is a circle so it is a lot more than 2 divisions even though the diagram fails to show so.

updated profile btw

i did read you post, and im curious why not do beam to 45 degree spinning mirror to cone mirror. The laser will be pretty intense at all times tho... and also the objects will receive the laser light at slightly different times depending on rotational speed, but like 1/3000 of a second). Does it really need to hit the sensors at EXACTLY the same time?

It won't work. It'll throw out a mess. You're thinking of a laser beam as a one-dimensional object while it is actually three, and each part of the dot (cross section, if you will) will be reflected in a different direction by the cone. Your circle will be hitting a curved surface, and so the circle shape will be distorted to hell. I'm not even sure what it'd look like. Maybe you should do it anyway (with a 5mW red) so you can see what kind of crazy image it would make.

bdgreenb said:

i did read you post, and im curious why not do beam to 45 degree spinning mirror to cone mirror. The laser will be pretty intense at all times tho... and also the objects will receive the laser light at slightly different times depending on rotational speed, but like 1/3000 of a second). Does it really need to hit the sensors at EXACTLY the same time?

Click to expand...

There are two reasons for this. First i'm reading sensors at 180FPS and any flickering will lead the system to malfunction. Secondly I'm designing the system especially solid state. This will be the advantage of the build.

Cyparagon said:

It won't work. It'll throw out a mess. You're thinking of a laser beam as a one-dimensional object while it is actually three, and each part of the dot (cross section, if you will) will be reflected in a different direction by the cone. Your circle will be hitting a curved surface, and so the circle shape will be distorted to hell. I'm not even sure what it'd look like. Maybe you should do it anyway (with a 5mW red) so you can see what kind of crazy image it would make.

Click to expand...

I really think it's going to work. There are cone mirrors produced only for this kind of operation and Bosch seems to use it on their new leveler.



And quoting from bosch laser leveller review page:

...A typical rotary laser spins a pin-point laser fast enough to project a straight line 360 degrees along a single axis. Bosch took a different approach with the GLL2-80; inside a self-leveling vial on the top of the device is a conical mirror suspended over a dot laser. The beam of light is split by the tip of the conical mirror, projecting a level line in every direction that is accurate to 1/4 in. at a distance of 100 ft. A similar vial on the side of the device holds a laser that creates a 360-degree plumb line. What you end up with is the stability of a stationary laser, but it still gives you a crisp 360-degree line...

Bosch's 360-Degree Dual-Plane Laser Level is Affordable and Versatile - Fine Homebuilding

Hope you have done your safety homework. 1W isn't so useful if you can't see anymore.

Laser shows from the 70s have an easy home solution for what you require.
If you really wanted to do it crudely a tem01 beam could possibly work.
Plus existing solutions courtesy of pangolin;

Soulstorm said:

Hope you have done your safety homework. 1W isn't so useful if you can't see anymore.

Laser shows from the 70s have an easy home solution for what you require.
If you really wanted to do it crudely a tem01 beam could possibly work.
Plus existing solutions courtesy of pangolin;

Click to expand...

Problem is not the mirror the laser itself. I can buy or make the mirror. All i need is advice on IR laser that shoots out a round beam with low divergence and >1W.

Why all IR lasers I've seen is focusable not shoots beam like green lasers? Is there an optic limitation?

I have few protection glasses for different wavelengths btw.

Cyparagon said:

It won't work. It'll throw out a mess. You're thinking of a laser beam as a one-dimensional object while it is actually three, and each part of the dot (cross section, if you will) will be reflected in a different direction by the cone. Your circle will be hitting a curved surface, and so the circle shape will be distorted to hell. I'm not even sure what it'd look like. Maybe you should do it anyway (with a 5mW red) so you can see what kind of crazy image it would make.

Click to expand...

If anyone here thought of lasers as 1 dimensional I would be worried.
I was thinking of it more 4 dimensionally, as I usually do, since I don't mind waiting. And he's not trying to make it a prettydisco show. it has to hit all sensors simultaneously so I would think more divergence would help a bit if sensors are on slightly diff plane

If its not critical for the power to be evenly distributed around, go for it. I think you should cut the power way back hough, especially since you are just using sensors. I reckon just make sure it's sharp and shiny, and that you take the proper safety precautions. You might could compensate for imperfections in the mirror by changing the sensor placement. Mind my asking, whatcha making?