Yellow laser image projection

[nikosb]

I want to combine a red and green laser to produce a yellowish laser beam and then project an image like a cross, line or circle with the yellowish color at a distance of 10 to 15meters ahead as shown in the image

My first thought was to use a diffraction grating lens but I am not sure how that would work with red and green laser beams combined? Can it be done this way or does red and green laser beams behave differently with the same diffraction grating lense?

 

[grainde]

Please check before starting a new thread. There are many threads covering this topic, just type combining yellow in the search bar...

 

[gozert]

I doubt that spreading a combined beam would work. Don't take my word for it though, still learning.

 

[nikosb]

Please check before starting a new thread. There are many threads covering this topic, just type combining yellow in the search bar...

I did a search on combined yellow laser and there are lot of threads on DIY yellow laser but I didn't see anything about the effect of a diffraction grating lense or expanding beam. Feel free to post a link to the thread that covers this topic.

 

[grainde]

I want to combine a red and green laser to produce a yellowish laser beam...

You have to combine the beams first and then you will get lots of green and red dots after the grating or in your case 2 lines/crosses of the two colours. This has also been discussed. If you use a scanner it might work.

 

[nikosb]

You have to combine the beams first and then you will get lots of green and red dots after the grating or in your case 2 lines/crosses of the two colours. This has also been discussed. If you use a scanner it might work.

I am not familiar with a scanner. Is it expensive? Where can I find out more about it?

 

[starlight]

http://pages.ebay.com/link/?nav=item.view&id=261682067344&alt=web

 

[Grix]

I am not familiar with a scanner. Is it expensive? Where can I find out more about it?

Yes, scanners are expensive, they plus a control board and power supply is maybe $100 total for a cheap set, then you need a DAC which is at least $50, then software which you might find for free but maybe not depending on the DAC

 

[mojo_1234]

If you just need a circle take some small electro motor and attach a small mirror. When rotating with quite high speed you'll have the same effect as with a more expensive scanner. The size of the projected circle depends on the projection distance and for sure on the angle the mirrors is glued to the rotation axis.

 

[nikosb]

You have to combine the beams first and then you will get lots of green and red dots after the grating or in your case 2 lines/crosses of the two colours. This has also been discussed. If you use a scanner it might work.

I actually found the thread discussing this

http://laserpointerforums.com/f40/rgb-diffraction-grating-48071.html

thanks for pointing out that it was discussed before. The shape of the diffraction grating in my application is not a simple circle so I guess it would be harder to align the diffracted beams. Regarding using a scanner I was thinking of trying something like this:

Laser Image Projector

where instead of the green laser, I have the beam from the combined green and red lasers. For the very basic operation I would need a concave lens for expanding the beam and convex lens for focusing and it does not have to be professional quality. Do you think that could work?

 

[ARG]

My first thought was to use a diffraction grating lens but I am not sure how that would work with red and green laser beams combined? Can it be done this way or does red and green laser beams behave differently with the same diffraction grating lense?

Check out this thread
http://laserpointerforums.com/f51/reference-guide-how-combine-lasers-77449.html#post1113793