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Laser marking/directing system

Started by Klaus Kragelund December 18, 2021
Hi

I am working on a project, just for my own business

I need a laser marking system, that can show a cross hair or other visible marking on a cardboard box up to 4 meters away

Initial thought would be class 1 laser (no approvals?) and then 2 steppers in a mechanical arrangement to provide x and y functions

I can add a USB camera to home in the laser, so the mechanism does not need to be precise

Any hints for the cheapest system?

Maybe using the optical drive for a cheap  projector?

I need to be able to buy it for my own production

Regards

Klaus 

--
Klaus
On 18/12/2021 16:53, Klaus Kragelund wrote:
> Hi > > I am working on a project, just for my own business > > I need a laser marking system, that can show a cross hair or other > visible marking on a cardboard box up to 4 meters away > > Initial thought would be class 1 laser (no approvals?) and then 2 > steppers in a mechanical arrangement to provide x and y functions
Traditional old school way to do it would be two axis mirror galvos and analogue signals to determine the position of the laser dot.
> I can add a USB camera to home in the laser, so the mechanism does not > need to be precise > > Any hints for the cheapest system?
There are some toy laser projectors that can put a diffraction pattern very like a cross onto a target and some fairly bright white light LED torches that can focus the LED die onto a target at about that range. If you can make a mask for one of those then you can nail it. This is a rather pretty colourful example of the technique using Venus as the light source and a fine fabric as the diffraction mesh. https://www.atoptics.co.uk/fz956.htm
> Maybe using the optical drive for a cheap  projector? > > I need to be able to buy it for my own production
So you are intending to make these to sell as opposed to a one off? My money would be to project the cross pattern with Fourier optics so there are no moving parts and it is very cheap to make. -- Regards, Martin Brown
18.12.21 17:53, Klaus Kragelund   wrote:
>Hi > >I am working on a project, just for my own business > >I need a laser marking system, that can show a cross hair or other visible marking on a cardboard box up to 4 meters away > >Initial thought would be class 1 laser (no approvals?) and then 2 steppers in a mechanical arrangement to provide x and y functions > >I can add a USB camera to home in the laser, so the mechanism does not need to be precise > >Any hints for the cheapest system? > >Maybe using the optical drive for a cheap projector? > >I need to be able to buy it for my own production >
I can get cheap servos: https://m.aliexpress.com/item/4000903254039.html But how to align mirrors to translate those servos to xy plane -- Klaus
On Saturday, 18 December 2021 at 18:22:41 UTC+1, Martin Brown wrote:
> On 18/12/2021 16:53, Klaus Kragelund wrote: > > Hi > > > > I am working on a project, just for my own business > > > > I need a laser marking system, that can show a cross hair or other > > visible marking on a cardboard box up to 4 meters away > > > > Initial thought would be class 1 laser (no approvals?) and then 2 > > steppers in a mechanical arrangement to provide x and y functions > Traditional old school way to do it would be two axis mirror galvos and > analogue signals to determine the position of the laser dot. > > I can add a USB camera to home in the laser, so the mechanism does not > > need to be precise > > > > Any hints for the cheapest system? > There are some toy laser projectors that can put a diffraction pattern > very like a cross onto a target and some fairly bright white light LED > torches that can focus the LED die onto a target at about that range. If > you can make a mask for one of those then you can nail it. > > This is a rather pretty colourful example of the technique using Venus > as the light source and a fine fabric as the diffraction mesh. > > https://www.atoptics.co.uk/fz956.htm
Looks interesting
> > Maybe using the optical drive for a cheap projector? > > > > I need to be able to buy it for my own production > So you are intending to make these to sell as opposed to a one off?
Yes. If my idea pans out I will be selling a, lot of them
> > My money would be to project the cross pattern with Fourier optics so > there are no moving parts and it is very cheap to make.
I have not heard about Fourier optics before. I need a max deflection of maybe 45 degrees. So I am guessing it would not be usable
On 18/12/2021 17:53, Klaus Kragelund wrote:
> On Saturday, 18 December 2021 at 18:22:41 UTC+1, Martin Brown wrote: >> On 18/12/2021 16:53, Klaus Kragelund wrote: >>> Hi >>> >>> I am working on a project, just for my own business >>> >>> I need a laser marking system, that can show a cross hair or other >>> visible marking on a cardboard box up to 4 meters away >> >> My money would be to project the cross pattern with Fourier optics so >> there are no moving parts and it is very cheap to make.
> I have not heard about Fourier optics before. I need a max deflection of maybe 45 degrees. So I am guessing it would not be usable
My next suggestion then would be two laser light sources projecting a point of light and a cylinder lens to spread it out along a line. To try it out crudely just find some clear Perspex or glass rod. -- Regards, Martin Brown
On a sunny day (Sat, 18 Dec 2021 17:53:04 +0100) it happened Klaus Kragelund 
<klauskvik@hotmail.com> wrote in <tscheppe.9r0h3ieyfga9@nntp.aioe.org>:

>Hi > >I am working on a project, just for my own business > >I need a laser marking system, that can show a cross hair or other visible marking on a cardboard box up to 4 meters away > >Initial thought would be class 1 laser (no approvals?) and then 2 steppers in a mechanical arrangement to provide x and y >functions > >I can add a USB camera to home in the laser, so the mechanism does not need to be precise > >Any hints for the cheapest system? > >Maybe using the optical drive for a cheap projector? > >I need to be able to buy it for my own production
Use RC servos and 1 PIC micro red laser diodes are cheap on ebay. http://panteltje.com/panteltje/pic/camc_pic/ Or you could get one of those xy movable video security cameras and put a laser diode on it. Wrote a controller for mine long time ago. Then you have the camera pointing at the target all the time. https://www.ebay.com/itm/324772560866
On a sunny day (Sat, 18 Dec 2021 18:37:49 +0100) it happened Klaus Kragelund 
<klauskvik@hotmail.com> wrote in <tscheppe.1mvsh2cmn565z@nntp.aioe.org>:

>18.12.21 17:53, Klaus Kragelund wrote: >>Hi >> >>I am working on a project, just for my own business >> >>I need a laser marking system, that can show a cross hair or other visible marking on a cardboard box up to 4 meters away >> >>Initial thought would be class 1 laser (no approvals?) and then 2 steppers in a mechanical arrangement to provide x and y >>functions >> >>I can add a USB camera to home in the laser, so the mechanism does not need to be precise >> >>Any hints for the cheapest system? >> >>Maybe using the optical drive for a cheap projector? >> >>I need to be able to buy it for my own production >> > >I can get cheap servos: > >https://m.aliexpress.com/item/4000903254039.html > >But how to align mirrors to translate those servos to xy plane
5 cheap red laser diodes make a cross: https://www.ebay.com/itm/192413550626 I bought ten for what was it? 2$58 in 2914, so now they ask 6$89...
On 18/12/2021 5:37 pm, Klaus Kragelund wrote:
> 18.12.21 17:53, Klaus Kragelund&nbsp;&nbsp; wrote: >> Hi >> >> I am working on a project, just for my own business >> >> I need a laser marking system, that can show a cross hair or other >> visible marking on a cardboard box up to 4 meters away >> >> Initial thought would be class 1 laser (no approvals?) and then 2 >> steppers in a mechanical arrangement to provide x and y functions >> >> I can add a USB camera to home in the laser, so the mechanism does not >> need to be precise >> >> Any hints for the cheapest system? >> >> Maybe using the optical drive for a cheap&nbsp; projector? >> >> I need to be able to buy it for my own production >> > > I can get cheap servos: > > https://m.aliexpress.com/item/4000903254039.html > > But how to align mirrors to translate those servos to xy plane > > > -- > Klaus
Can a radio control servo move fast enough to fool the eye? piglet
On 12/18/2021 9:53 AM, Klaus Kragelund wrote:
> I am working on a project, just for my own business > > I need a laser marking system, that can show a cross hair or other visible > marking on a cardboard box up to 4 meters away
To be clear, you are not intending on actually *marking* the target but, rather, *indicating* a position on it (?)
> Initial thought would be class 1 laser (no approvals?) and then 2 steppers in a > mechanical arrangement to provide x and y functions
Slow. Is the target in motion? How "static" must the indication be?
> I can add a USB camera to home in the laser, so the mechanism does not need to > be precise
I don't think I understand what this adds. Or, are you claiming there are other reference data on the target that could be visually identified (with the camera) and used to adjust the position of your laser indication?
> Any hints for the cheapest system?
If you have a general idea where the target will reside ("constrained location"), a vibrating mirror with a (physical) gating aperture (to ensure the laser never is active in directions that could cause injury/damage). Gate the beam on/off based on where the mirror happens to be, presently. (let it remain off when the reflection wouldn't be where you wanted it to be) You can mock up a single DoF deflector with a mirror mounted on a speaker (driving the speaker to deflect the beam)
> Maybe using the optical drive for a cheap projector? > > I need to be able to buy it for my own production
On Saturday, 18 December 2021 at 19:45:24 UTC+1, Jan Panteltje wrote:
> On a sunny day (Sat, 18 Dec 2021 17:53:04 +0100) it happened Klaus Kragelund > <klau...@hotmail.com> wrote in <tscheppe.9...@nntp.aioe.org>: > >Hi > > > >I am working on a project, just for my own business > > > >I need a laser marking system, that can show a cross hair or other visible marking on a cardboard box up to 4 meters away > > > >Initial thought would be class 1 laser (no approvals?) and then 2 steppers in a mechanical arrangement to provide x and y > >functions > > > >I can add a USB camera to home in the laser, so the mechanism does not need to be precise > > > >Any hints for the cheapest system? > > > >Maybe using the optical drive for a cheap projector? > > > >I need to be able to buy it for my own production > Use RC servos and 1 PIC micro > red laser diodes are cheap on ebay. > http://panteltje.com/panteltje/pic/camc_pic/ > > Or you could get one of those xy movable video security cameras and put a laser diode on it. > Wrote a controller for mine long time ago. > Then you have the camera pointing at the target all the time. > https://www.ebay.com/itm/324772560866
That is actually a very nice idea. Kills two birds with one stone :-) I then need to find a camera with an open SW/library. How did you go about finding the documentation for controlling them?