Rainbow dot?

[Elopement]

So it is possible then, with a custom build, to get a rainbow output, if custom built?

What size are we talking here?

 

[Dutch67]

So it is possible then, with a custom build, to get a rainbow output, if custom built?

What size are we talking here?

In order to properly see and distinguish all of the different colors, the dot would have to be pretty large. Most builds that combine colors turn the dot "white".

There are plenty of RGB builds out there specifically made to combine colors and make a white laser.

It would very difficult, I think, to make a rainbow dot as light doesn't have solid boundaries. It mixes and such with the other lights around it.

 

[diachi]

In order to properly see and distinguish all of the different colors, the dot would have to be pretty large. Most builds that combine colors turn the dot "white".

There are plenty of RGB builds out there specifically made to combine colors and make a white laser.

It would very difficult, I think, to make a rainbow dot as light doesn't have solid boundaries. It mixes and such with the other lights around it.

You'd end up with individual dots anyway, not a rainbow. You'd have distinct lines. The only laser I'm aware of capable of achieving an actual rainbow is a supercontinuum laser, which is $$$$$. You could use RGB and get all of the colours, but not all at once, unless you were using a laser projector.

 

[CurtisOliver]

Please take a look at this thread made by a member here recently. It will show you how much customisation and hard work had to go into achieving what you seem to want. You will also get a sense of scale, and what components will be needed. Do check out his 3D model. It is view-able online and you can explode the drawing to see all the components. Very useful indeed.

http://laserpointerforums.com/f44/arctic-s-open-source-rgb-laser-host-99595.html

 

[Radim]

I'm not looking for an external device to shine a laser on to, I am looking for an all-in-one pen which can emit an assortment of coloured laser in a rainbow like fashion into a single dot please.

What about this? http://laserpointerforums.com/f44/arctic-s-open-source-rgb-laser-host-99595.html

Edit: I did not see Oliver's post before, but you have at least two recommendations now.

 

[Elopement]

Interesting, perhaps then it would be better to have a circle of coloured dots, like a colour wheel, only, overlapping, if they don't have boundaries as you suggest.

 

[Encap]

None of them is going to make a dot or dots with all the colors of the rainbow.

Rainbows span a continuous spectrum of colours. Any distinct bands perceived are an artefact of human colour vision, and no banding of any type is seen in a black-and-white photo of a rainbow, only a smooth gradation of intensity to a maximum, then fading towards the other side

The devices are just using Red, Green , and Blue laser light together to make something that looks/appears white when balanced correctly or whatever mix of RGB to make whatever color.

 

[HydroSean]

What you could do is diffract a white laser like that Ar/Kr and then collimate the beam just after it is diffracted, then you would have somewhat of a rainbow dot. it'd be pretty fat and it'd also have gaps in it but it would most likely work. just a thought

 

[diachi]

What you could do is diffract a white laser like that Ar/Kr and then collimate the beam just after it is diffracted, then you would have somewhat of a rainbow dot. it'd be pretty fat and it'd also have gaps in it but it would most likely work. just a thought

Only benefit of Ar/Kr here is the increased number of lines, instead of say just 3 (RGB). Still ends up with the same issues - i.e. not really a rainbow. I suppose not having to combine the beams with dichros would be a benefit too...

 

[HydroSean]

Only benefit of Ar/Kr here is the increased number of lines, instead of say just 3 (RGB). Still ends up with the same issues - i.e. not really a rainbow. I suppose not having to combine the beams with dichros would be a benefit too...

Yeah I guess you could use an individual laser diode for 405, 445, 473, 520, 532, 638, and 650 and then use an RGB for the cyan, yellow, and white colors. Then build a fixture with lenses and mirrors to hold all the lasers/modules and have them point in the order of the rainbow in a small spot. would be super expensive though. Like over $1500 just for a rainbow dot...

 

[Radim]

Interesting, perhaps then it would be better to have a circle of coloured dots, like a colour wheel, only, overlapping, if they don't have boundaries as you suggest.

For this complicated stuff get RGB laser projector. You have three lasers which create you a lot of colors and galvos for shape desired.

 

[CurtisOliver]

Looks like you need a super continuum white laser to me. Good luck on affording that option. Even they aren't perfect rainbows.

 

[Elopement]

For this complicated stuff get RGB laser projector. You have three lasers which create you a lot of colors and galvos for shape desired.

RGB laser projector pens seem too bulky for what I need, I was looking for the whole thing in pen format.

Perhaps there is a diode that can do two or more colours, so that the components can be kept to a small size?

 

[diachi]

RGB laser projector pens seem too bulky for what I need, I was looking for the whole thing in pen format.

Perhaps there is a diode that can do two or more colours, so that the components can be kept to a small size?

There's one that I'm aware of that can do 405nm and 650nm, fairly low power.

You're not going to get this (RGB) in something the size of a pen.

 

[Dutch67]

There's one that I'm aware of that can do 405nm and 650nm, fairly low power.

You're not going to get this (RGB) in something the size of a pen.

Wait...Are you saying there's a diode that emits 650nm and 405?:thinking:

 

[diachi]

Wait...Are you saying there's a diode that emits 650nm and 405?:thinking:

The KES300A from the PS3 CD/DVD/BR drive. Has IR/650/405, one for each format.

Pinout:

Bog standard 5.6mm package, just with more pins:

You can run both 405 and 650 at once for magenta, although at a reduced power for each.