How do I stretch a laser from a beam into a sheet?

[DaveE]

The "Y" in "DIY" stands for yourself. We can't tell you the best way for you to solve the mechanical mounting problem with your tools, desires, and experience.

 

[sophiecentaur]

the best way for you to solve the mechanical mounting problem with your tools, desires, and experience

A totally personal choice, of course. For anyone to help you get to your goal you need to describe the problem exactly. The easiest solution would almost certainly to have been to buy a cheapo laserlevel. Now you have spent $40 on your posh lens, you are pretty well forced to use it. Also, a level is a level and useful in its own right.

 

[sbrothy]

I'm almost loathe to suggest it but you could formulate a detailed question for ChatGPT and ask the educated and intelligent people on here (which excludes me) bout the details that eludes you....

EDIT: I've had success with that MO before....

 

[sophiecentaur]

formulate a detailed question for ChatGPT

I'd bet that ChatGPT uses PF as a source for 'good ideas'. It has to get them somewhere as it has nothing of its own to give.

 

[sbrothy]

I'd bet that ChatGPT uses PF as a source for 'good ideas'. It has to get them somewhere as it has nothing of its own to give.

Yeah, in reality I'd be like searching PF and ask for elaboration on a particular subject.

EDIT: You *could* probably cut out ChatGPT but as I said when I formulated my questions in detail I was actually quite pleased with the answers. Except the parts I needed explained in more detail.

Here's an example (I knew I needed to profile the laser but I wanted ChatGPT to offer solutions, also with the lenses):

Please explain the demands, details and/or specifications of a 532 nanometer laser for use in a home build Raman spectrometer with a 2 lens setup. Specifically what, if anything, needs to be checked or done with regards to the laser for optimal focusing back and forth through the lens focusing the beam onto the sample in order to pick up the Raman backscattering.

EDIT: Or rather, I wanted it to point out to me which values were important to profile.
EDIT2: It "liked" my question("Nice project — fun and doable."? I wonder where these opinions come from? And what constitutes a stupid or inane question?) and I got a surprising amount of math back at me!

 

[sbrothy]

Here's the follow-up:

Please provide detailed instructions and specifications for building laser beam profilers for a 532 nanometer laser based on all techniques within DIY range. Specifically I want you to include the knife edge and camera techniques as well as any alternatives.

Also a lot of math. Obviously.

 

[sbrothy]

I'd bet that ChatGPT uses PF as a source for 'good ideas'. It has to get them somewhere as it has nothing of its own to give.

You might want to give this thread a look if you haven't already:

Thread 'Why have the number of questions declined over recent years?'

Dec 12, 2025

It's not just at Phsyics Forums, as for example, this graph of the monthly question rate at stack overflow:

• rcgldr
• Replies: 13
• Forum: Feedback and Announcements

• 

 

[LightningInAJar]

I'm almost loathe to suggest it but you could formulate a detailed question for ChatGPT and ask the educated and intelligent people on here (which excludes me) bout the details that eludes you....

EDIT: I've had success with that MO before....

Chatgpt is the first place I went when asking about lenses. YouTube helped more.

 

[sbrothy]

Yeah well, I'm not much for videos. I like to read.

 

[sophiecentaur]

Chatgpt is the first place I went when asking about lenses. YouTube helped more.

You have the necessary info about the lens and the laser. What you need is practical advice for the 'under-tooled'. If you had some modest machine tools then you'd do this easily. But, as I have already pointed out, you haven't shown us the actual problem. I wonder why.

 

[sbrothy]

Undertooled?

EDIT: And this is a month-old picture.

 

[sbrothy]

Nah, my basic problem is that I'm not made of money and I need to buy the things I need step by step. And then I'm also not exactly great at math. I'll make it work but it'll take some time. Also I have other, way more serious, stuff going on in my life.

 

[sbrothy]

I mean I know how to solve an ODE but, but luckily I'm teamed up with a civil engineer. I recently conspired with his wife to get him off the booze so we're getting there.

 

[sbrothy]

Undertooled?

View attachment 368258


EDIT: And this is a month-old picture.

Ah you meant perhaps in the qualification-department? Fair enough. Don't worry. I'll the there.

 

[LightningInAJar]

Just a cheap green laser pen about 2cm diameter. Less the 5mm laser beam. Roughly 8mm diameter Powell lens.

 

[sbrothy]

I have several of the 532nm green ones. Disassembled they're the size of my thumb nail. Also red ones.

Well, I found out that a near IR laser might be better better suited for the job. You can follow my antics here:

Optical Post in thread 'Arduino-based Raman spectrometer for drug identification'

Dec 19, 2025

So time to get serious.

If anyone disagree with any of the following please speak now or forever hold you silence.

All this 532 nm green laser stuff looked good on the surface but as it turns out the optimal choice seems to be a 785 nm (near-IR) laser. Specifically because it reduces fluorescence. I don't intend to make it a handheld device. If I buy from a reputable source I might be able to skip some of the profiling...

• sbrothy

 

[sophiecentaur]

Undertooled?

Sorry, no offence intended. I was referring to a drill, a lathe, a milling machine machine, a band saw and even a bench with a vise. Those 'tools' make a job like yours a doddle. It's the border between ee and metal bashing that determines how easy some jobs can be - that is if you can't buy ready made parts.
A vise and a small pillar drill (always second hand for me!!) make drilling holes in the right place possible and getting the right diameter too.

 

[DaveE]

Sorry, no offence intended. I was referring to a drill, a lathe, a milling machine machine, a band saw and even a bench with a vise. Those 'tools' make a job like yours a doddle. It's the border between ee and metal bashing that determines how easy some jobs can be - that is if you can't buy ready made parts.
A vise and a small pillar drill (always second hand for me!!) make drilling holes in the right place possible and getting the right diameter too.

TIL: Pillar Drill = Drill Press (I think). Y'all talk funny over there.

Anyway lathes and milling machines aren't required. I could do this with a hack saw, a cordless drill, a file, and an assortment of tape, screws, and glue. Also great deal of patience, creativity, and forgiveness for a kludgy looking result. However, I consider myself and expert on doing things badly with the wrong tools to get a good enough result. Yes, I think I can make a slot in a block of aluminum with a hand drill and a file.

What's really needed is desire, initiative, and a few failed attempts. It doesn't sound like that's in the cards this time.

PS: Also a vise, I'll need that or some clamps.

 

[sbrothy]

Sorry, no offence intended. I was referring to a drill, a lathe, a milling machine machine, a band saw and even a bench with a vise. Those 'tools' make a job like yours a doddle. It's the border between ee and metal bashing that determines how easy some jobs can be - that is if you can't buy ready made parts.
A vise and a small pillar drill (always second hand for me!!) make drilling holes in the right place possible and getting the right diameter too.

Well, as you know from our previous "altercation" I own a Devil (tm) Forge, a plasma burner / TIG welder and a comprressoe

 

[sbrothy]

I started trying to set up a forge amassing equipment like the Devil's Forge and a plasma burner, hydraulic presses and so on. I then had to set up a proper comapany because the number of private persons wanting to have an smithy in thir backyard was "surprisingly" small. My company is now called (Odense is the 3rd largest city in Denmark after Copehagen and Århus):

My one-man firm is called "Odense Metallurgy, Electronics, Chemistry & Computing", which kind of covers it all. I'll admit it's mostly for renting a commercial workshop, and perhaps obtaining ISO-certifications not available to private individuals, for instance LASERS too powerful to be accessably to private individuals.

I plan on using wood to prototype my first attempt.

 

[sophiecentaur]

Y'all talk funny over there.

Gor blimey guv'nor. Strike me pink! (Apologies to Dick Van Dyke.)

the number of private persons wanting to have an smithy in thir backyard was "surprisingly" small.

I always fancied something like that myself but my requirements are smaller and finer than blacksmithing will produce. Too much investment for a brief bit of fun for me.

 

[sophiecentaur]

I plan on using wood to prototype my first attempt.

Why not cast something in alloy? Use your existing skill to support your present interest.