Why does my red dot look like a bar instead of a nice red round dot?
Does this go through a beam combiner between the tube and m1?
I’ve never seen a diode do this, so I’m not clear what would cause it.
If you detail how this visible led is generated and introduced into the laser beam path, it might help us to help you figure it out.
If it’s something like an SPT tube that has this led/beam combiner internally, you’ll have to ask the vendor as it’s unlikely serviceable.
Hi.
Hard to tell using the provided information and from a digital pic, but if it’s a few mW pointer, could be that the vertical grate has broken or have been nudged somehow.
If the originally roundish beam has passed through a few mirrors, that pattern might be a result of projection onto an angled surface.
Regards,
Sam
Yes the red dot is passing through a beam combiner. My tube is a normal glass tube, it does not have any led/beam combiner internally. I have a red dot light right next to a laser tube output.
I just wonder it is normal for red light to look like a bar instead of dot on mirror 1, mirror 2 and mirror 3.
Fortenutly, red dot looks normal at
mirror 3 - honeycomb relation.
What do you mean by “vertical grate”?
Hi.
Rather than “normal” optics, low power diode laser beams like laser pointers are often collimated (and manipulated if patterns other than round are required) with grates.
It is a very cheap, easy and convenient way to produce a beam that stays relatively uniform in diameter/shape over a long distance.
IOW, the beam is collimated well.
The downside of that method is that the dot/shape looks “granular” and shows an interference pattern, but usually that doesn’t matter in laser pointer and AV use.
And if it does matter, other methods of collimation are used.
If the grate(s) fail(s) or are thrown out of alignment, the collimation changes and the resulting beam changes shape.
Well, there’s no problem then, that location is the only one that actually matters.
From the title I for one assumed that the dot is elongated in the work surface as well.
The elongation of the dot in the mirrors is probably by design, in order to preserve the beam strength as well as possible.
Laser beams collimated with grates do not behave that well with conventional mirrors or optics.
Regards,
Sam
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Than thank you very much, if there isn’t a problem.
I assumed if red dot was nice round dot at work surface that was normal, but then I wondered why did my red dot look like a bar at mirror 1 and mirror 2.
Regards, thank you!
Hi.
You’re welcome.
Regards,
Sam
Just out of curiosity, can you show a picture with the red dot on M3?, if you have an elongated bar on the other mirrors but not on the last mirror…I would like to know how it can be transformed into a dot…
What do you mean by that?
Ditto
I would like to read about grates used in these types of lasers to change their pattern, I assume @bernd.dk would also… do you have a link?
It’s just badly out of focus, exactly like in a “wall test” for a diode laser. The focus is (probably) set a meter or two out from the red dot laser, so it’s mostly focused at M3 and the laser focus lens will mash it down into a smaller dot.
When the beam is focused into a “dot”, it’s still a bar, but it’s small enough and bright enough you can’t distinguish the shape.
This is a focused red dot dimmed by a polarizing filter, but you can still see the slightly oblong shape:
What a simple and easy explanation, thank you.
hi
you can order on amazon red dot led laser for co2 alignment calibration cost is ~2 x of line laser model i have on order 2 ver 1 is from laser head to tube and 2nd is 10mm diameter for my gig in front of tube laser i do not know if web links are ok on this forum
i am reconditioning my gwklaser lc1390n co2 150w so i needed tools for it
Cloudray Diode Module Red Dot Set Hole Diameter 24mm and 25mm
omtech Precision Optical Adjustment: The precision of this quicker and safer
alignment tool is amplified by its compact 0.5 mm beam spot, ensuring
accurate alignment throughout its 7000 hour lifespan.
Easy Installation: The straight collet allows this upgraded CO2 laser
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additional tools
dusan2819
Links are OK here as long as you’re not pushing a product. They are very good for clearing up what you’re talking about.
hi
links are to dynamic so descriptions is better
OMTech CO2 Laser Alignment Tool, Precision Red Laser Pointer for 50W 60W 80W 100W 130W 150W Laser Engravers Engraving Marking Cutting Machines, Upgraded Visible Mirror Alignment Laser Path Guide
Cloudray Diode Module Red Dot Set Hole Diameter 24mm Positioning DC 5V for C SeriesDIY Co2 Laser Head
dusan2819
I can find Cloudray, but don’t see anything like you’re referring?
Can you copy the link from the actual item page and post it?
Is it this one from Amazon? Are you looking at the same product from Cloudray?
Have you thought about one of these?
Do you have a C series head/tube setup?