Welcome to Laser Pointer Forums - discuss green laser pointers, blue laser pointers, and all types of lasers



How to achieve 0.01mm laser spot size?

rajhlinux

Member
Joined
Dec 26, 2020
Messages
40
Points
8
I can't find any information on the internet for such basic task.

What are the proper steps, procedure, tools, optics and materials needed to focus a 405nm laser close to 0.01mm (tolerance +/-0.01mm) all day long?

It's going to be this laser module:
NEJE 405nm 3500mW Laser Module

Thanks.
 



Alien Laser

Well-known member
Joined
Oct 6, 2015
Messages
1,326
Points
113
Are you sure the laser is 3500mW maybe pulse only i build some BDR209 and the single mode is the best
 

Encap

Well-known member
Joined
May 14, 2011
Messages
5,797
Points
113
I can't find any information on the internet for such basic task.

What are the proper steps, procedure, tools, optics and materials needed to focus a 405nm laser close to 0.01mm (tolerance +/-0.01mm) all day long?

It's going to be this laser module:
NEJE 405nm 3500mW Laser Module

Thanks.
Ask the Neje people -- LPF is not a babysitting forum to spoon feed dozens of answers to people living in a daydream of their own design and have no idea of what they are talking about, doing, or how to do it.

It says in the specifications:
Can Engrave:MDF/Balsa/Paper/Wood/Fabric/Plastic/Leather/Plywood/Foam Paper/Anodized Aluminum
Can Not Engrave:Metal/Glass/Stone/Ceramics/PCB/Stainless Steel/Reflective Material/ Transparent Material

Are you sure the laser is 3500mW maybe pulse only i build some BDR209 and the single mode is the best

It is 3500 mW input power--it uses a sharp 350mW 405 laser diode---so the specs say see: https://neje.shop/products/3500mw-laser-module-with-interface-transfer-board
Typical Chinese garbage--toy level stuff
 
Last edited:

Alien Laser

Well-known member
Joined
Oct 6, 2015
Messages
1,326
Points
113
I seen the link but i did not like posting it i was confused since i never seen a 3.5W 405nm i was thinking maybe i miss something since i haven bin in the forum
 

rajhlinux

Member
Joined
Dec 26, 2020
Messages
40
Points
8
Here is the link where I'm planning to buy the module, lots of good reviews:

banggood.com/NEJE-405nm-450nm-Laser-Module-Variable-Focus-PWM-Modulation-for-NEJE-Master-Laser-Engraver-Deep-Carving-Desktop-Logo-Printer-p-1592200.html?utm_source=googleshopping&utm_medium=cpc_organic&gmcCountry=US&utm_content=minha&utm_campaign=minha-us-pc&currency=USD&cur_warehouse=CN&createTmp=1&ID=6282515&utm_source=googleshopping&utm_medium=cpc_bgs&utm_content=frank&utm_campaign=frank-ssc-us-all-newcustom-ncv90-0623-11sale&ad_id=443948744865&gclid=Cj0KCQiA_qD_BRDiARIsANjZ2LD0bBQWDLP5ywX2u7BX5Go5J4101y6hxujqDQv4rR4Zto8Fx0BgZ_IaAjEyEALw_wcB

Wavelength405nm
Radiator Size30*60mm
MaterialCopper + Aluminum
Weight116g
Input12V280mA (about 3500mw)
Output Optical Power600mw
PWM20KHz / 3.3V
Temperature SensorYes
Focus Range10mm-50mm ( 10mm is best)
Best Focal Length10mm from the light exit
Focus Diameter0.01mm
Drive PositionBuilt-in
Is the Power AdjustablePWM can be adjusted
Drive ProtectionSurge Protection, Overvoltage Protection
Input Powerapprox. 12V280ma (including fan power)
Line Length300mm
Control Line Installation MethodIntegrated
Fan Size30*10mm
Fan Speed10,000 rpm
Controllable TemperatureLess than 60 degrees Celsius
Interface Specification4pin PH2.0 (red: 12V, black: GND, yellow: PWM, green: temperature signal)


It's specification says it's Focus Diameter 0.01mm, I read the same specification on a different link and it shows it's Focus Diameter 0.04mm:

nl.aliexpress.com/item/33002050429.html?spm=a2g0z.12057483.0.0.76532ff4u1vyNB

Hc8f2940876d34d199e57f08b4e54a811g.jpg

Anyhow accuracy around 0.01 - 0.04mm is somewhat good enough for my needs...

But for the sake of curiosity and self educating, how can I change/swap out the optics and upgrade them to a more advance optics which will be spot on with a focus point of 0.01mm?

Also, how do you drive your BDR209 laser? Do you implement TTL/PWM or CW?
 

rajhlinux

Member
Joined
Dec 26, 2020
Messages
40
Points
8
Ask the Neje people --this is not a babysitting forum to spoon feed answer to people living in a daydream of their own design and have no idea of what they are talking about, doing, or how to do it.

It says in the specifications:
Can Engrave:MDF/Balsa/Paper/Wood/Fabric/Plastic/Leather/Plywood/Foam Paper/Anodized Aluminum
Can Not Engrave:Metal/Glass/Stone/Ceramics/PCB/Stainless Steel/Reflective Material/ Transparent Material

Well that escalated really quickly... those specifications has no meaning to me. I need to use it for photoresist with a tolerance of 0.01mm

You're talk about something that is not related to what this thread is asking for, how can I achieve 0.01mm spot size?

Go troll else where if you don't have the proper knowledge for such question. A forum is a place where people ask question, if you got a problem with me ask basic questions then get lost.

Typical Chinese garbage--toy level stuff

Well it's something I can buy and actually complete a project, if you have any sources, books, articles or links of how I can buy raw laser diodes and drive them with TTL/PWM that would be great.
 

rajhlinux

Member
Joined
Dec 26, 2020
Messages
40
Points
8
It can be focused i believe the front knob can be zoom in and out :unsure:

Yes, this particular laser module can be focusable but just for the sake of my own clarity, would like to know how I can implement a more advanced controlled method of achieving 0.01mm focus point at the etching/exposing/marking surface.

I did find some books and articles of using a CCD camera to implement "gaussian beam" profiler to estimate the most accurate (scientifically) focal point size. Basically the method involves shooting the laser into the CCD sensor. Would have to use special filters so that the laser would not damage the CCD sensor.

Problem is, before even thinking about testing the focal point with the help of a CCD camera sensor, what kinds of optics are needed to make the laser beam close to 0.01mm?
 

Unown (WILD)

Well-known member
Joined
Sep 4, 2020
Messages
390
Points
63
I don't think you can with this diode and lens. You also have to understand what encap means. People have to pay money for this kind of consultation so to get anything for free is a blessing and a kind act. Maybe with a gas laser and some expensive optics you can get the focal point that small but man I dunno, I'm not an expert in that.
 

rajhlinux

Member
Joined
Dec 26, 2020
Messages
40
Points
8
I don't think you can with this diode and lens. You also have to understand what encap means. People have to pay money for this kind of consultation so to get anything for free is a blessing and a kind act. Maybe with a gas laser and some expensive optics you can get the focal point that small but man I dunno, I'm not an expert in that.

Wow... was it so hard so say that I had to pay to get "consultation" for such focal point.

Lets be honest achieving 0.01mm with +/- 0.01m tolerance focal point isn't rocket science.

But anyhow I wouldn't mind paying for valid schematics for optics to start with.
As long you're not beating me in the head with price.
Obviously in my right mind, I won't pay anything until I know you have a valid institution degree in the related field of optics/photonics engineering. If anyone can prove that they have such background, I'll pay for optical cad drawings/schematics and have a company produce the optics for me. But then again this is just a project of mine, I'm not a company that needs this by heart.

There's already an intelligent person who made a high resolution "Laser Direct Lithography" using "encap's" "garbage" parts give or take about $100 or so. The project is open source and it's called "LDGRAPHY".

Here is the link to the project:
github.com/hzeller/ldgraphy

It's not perfect for my needs since I need it for QFN and FPGA PCB trace circuits which needs about 0.07mm traces.
I'm here to ask "real knowledgeable" people how this open source technology can be perfected to get the laser's focal point at least 0.05mm accurately all day so that exposing/marking/etching the photoresist at 0.07mm will be no problem.

The creator for that LDI project states that his open source LDI creation is reliable up to "~0.15mm" marking.
Now for stupid monkeys like "encap", he obviously can't comprehend the level of achievement "LDGRAPHY" truly is (no seriously he cant).
One needs to understand that there was no freaking external lens involved, and for around $100, open source project like "LDGRAPHY" can give you "~0.15mm" accuracy, that's mind blowing if you asked me.

I'm actually building this "ldgraphy" LDI device, everything is well documented by the creator (I mean who wouldn't, specially people who likes to learn and design their own PCBs).
The creator gave some ideas how to improve his open source LDI, one of which is using an f-theta lens (which I will try to test with using a laser printer f-theta lens, delivery is on its way).

But hey, if someone is willing to perfect this down to 0.01mm for a price... then how much?
 

Unown (WILD)

Well-known member
Joined
Sep 4, 2020
Messages
390
Points
63
I dunno, optics can get pretty expensive. You gotta understand that that diodes emitter isn't exactly small and precise. I don't know if this is accurate to say but maybe using a beam expander then a few corrective optics might help with the output but making it one hundredths of a millimeter is insanely small. We used to have a guy who knew a lot about optics but he was banned not too long ago. Lazerman121. He does have a facebook account. Maybe look him up
 

rajhlinux

Member
Joined
Dec 26, 2020
Messages
40
Points
8
I dunno, optics can get pretty expensive. You gotta understand that that diodes emitter isn't exactly small and precise. I don't know if this is accurate to say but maybe using a beam expander then a few corrective optics might help with the output but making it one hundredths of a millimeter is insanely small. We used to have a guy who knew a lot about optics but he was banned not too long ago. Lazerman121. He does have a facebook account. Maybe look him up

Its truly sad smart people that gets banned... I'll try to find and shoot him a message.
 

Alaskan

Well-known member
LPF Site Supporter
Joined
Jan 29, 2014
Messages
12,966
Points
113
Lazerman121 was given a short temporary ban, reinstated like what, two years ago? If you are who I think you are, you were permanently banned like a dozen times yet came back without objections.
 

Giannis_TDM

Well-known member
Joined
Apr 27, 2019
Messages
485
Points
63
Wow... was it so hard so say that I had to pay to get "consultation" for such focal point.

Lets be honest achieving 0.01mm with +/- 0.01m tolerance focal point isn't rocket science.

But anyhow I wouldn't mind paying for valid schematics for optics to start with.
As long you're not beating me in the head with price.
Obviously in my right mind, I won't pay anything until I know you have a valid institution degree in the related field of optics/photonics engineering. If anyone can prove that they have such background, I'll pay for optical cad drawings/schematics and have a company produce the optics for me. But then again this is just a project of mine, I'm not a company that needs this by heart.

There's already an intelligent person who made a high resolution "Laser Direct Lithography" using "encap's" "garbage" parts give or take about $100 or so. The project is open source and it's called "LDGRAPHY".

Here is the link to the project:
github.com/hzeller/ldgraphy

It's not perfect for my needs since I need it for QFN and FPGA PCB trace circuits which needs about 0.07mm traces.
I'm here to ask "real knowledgeable" people how this open source technology can be perfected to get the laser's focal point at least 0.05mm accurately all day so that exposing/marking/etching the photoresist at 0.07mm will be no problem.

The creator for that LDI project states that his open source LDI creation is reliable up to "~0.15mm" marking.
Now for stupid monkeys like "encap", he obviously can't comprehend the level of achievement "LDGRAPHY" truly is (no seriously he cant).
One needs to understand that there was no freaking external lens involved, and for around $100, open source project like "LDGRAPHY" can give you "~0.15mm" accuracy, that's mind blowing if you asked me.

I'm actually building this "ldgraphy" LDI device, everything is well documented by the creator (I mean who wouldn't, specially people who likes to learn and design their own PCBs).
The creator gave some ideas how to improve his open source LDI, one of which is using an f-theta lens (which I will try to test with using a laser printer f-theta lens, delivery is on its way).

But hey, if someone is willing to perfect this down to 0.01mm for a price... then how much
Take your calipers if you want to make SURE that its sub 0.05mm just look hard into it, may be difficult to get proper readings and make sure they have a good vernier scale Lol. Focus it down and try different lenses. Get a G2 lens from dtr. It has a short focal length that will get you the smallest spot possible. and Remarking on your point, If its not rocket science you already know how to do, You asking us is just wasting your precious time if it inst hard to do *right princess*? Also check your diode, If its 5.6mm in dia its the sharp diode, If its 3.8mm you got the good single mode BDR. If its not the BDR swap it out for one, gonna get you the smallest spot easily reaching 0.01mm since you know it is used in a blu ray writer so by default the spot has to be a lot smaller than that to write the data.
 

Unown (WILD)

Well-known member
Joined
Sep 4, 2020
Messages
390
Points
63
Lazerman121 was given a short temporary ban, reinstated like what, two years ago? If you are who I think you are, you were permanently banned like a dozen times yet came back without objections.
Do you want me to show your comment to Avery? He said not argue about it. Your slander about me stops now, Mr Alaskan
 

Anthony P

Well-known member
LPF Site Supporter
Joined
Oct 7, 2018
Messages
429
Points
63
I do not have a specific answer to the actual question... however, a beam that is first expanded can be focused to a finer point.
 




Top