A full guide of a diode laser beam focusing.
On this page, we describe all methods of laser beam focusing. Everything you need to know about different types of laser lenses.
A short gif animation about laser beam spot, focal depth, and focal range.
Learn more about 3 elements, G2, G7 and G8 laser lenses.
Diode laser beam focusing for
G2 lens (5-30 mm adjustable focal range)
3 Element lens (goes by default with all Endurance lasers).
(5-10 cm [2-4”] adjustable focal range)
a ruler is in cm (~2.5 cm = 1 inch)
Laser beam spot | Focal range | Focal depth (gif animation)
Getting started with Endurance laser lens pack.
All you need to know about Endurance laser lenses. Explore 3 elements, G2, G7 and G8 lenses.
Check your laser beam focus with a mirror Canon camera.
A detailed vide of how to use a mirror camera and photo filter and observe the laser beam spot.
Allows to get the minimum laser beam spot.
How to use a digital microscope and focus the laser
Laser beam focusing using different tools (black anodized metal card).
Once you hear the “beep” on minimum power it means that you are in focus. The louder noise is – the better is the focus.
by Florian Kelsch
Endurance laser beam quality research.
Improve the laser beam quality with a semicylindrical extra lens. Decreasing slow axes size.
Beginner Guide Correct Laser Focus Point (PDF) written by Florian Kelsch
What is inside the laser lenses.
Measuring of a focal length (range) for a different type of laser lens
Laser beam focusing on your DIY engraving machine like Ortur, Eleksmaker, CNCC Laseraxe, Aton, Wainlux, Neje and others.
Laser beam focusing on MakeBlock XY engraving plotter.
Improvement of laser beam focusing
Adding 3rd spacer and get a fixed focusing range
No need to focus on the laser again. You know the focal range written on an Endurance lasers business card.
Focusing of a triple beam 30 watt laser. A detailed video guide.
3 element laser lens focusing. Full written guide.
It is very important to set up a proper focus range on your diode lasers. If you are in focus then you can cut and engrave effectively, if not, then you will face some problems with engraving and cutting
Here is the guidance on how to set up a laser focus range on a 3D printer or CNC machine:
We experimented with an Endurance Anet A8 3D printer combo.
1. To set up “home”, that is to find 0 for the Z-axis we use the command “G28 Z0” for the Anet A8 3D printer.
2. We move the laser up to 50 mm above the Z-axis.
3. Measure the range between the lens and the worktop, it is 37 mm, it means that the laser is 13 mm below the 0 (50 mm – 37 mm).
4. The estimated laser focal range for the 3 elements regular lens is ~60 mm, so we need to move the laser up to the expected focal range, that is 60 mm + 13 mm = 73 mm, where 3 mm is the difference between the 0 and the actual laser position.
5. Run the g-code (test1.gc)
This g-code draws 20 lines by way of changing the Z-axis height starting from 64 mm (- 9 mm from the initial setting of 73 mm) up to 83 mm (+10 mm).
The optimal focal range is considered the one when the thinnest line (on a piece of wood or plywood) or most clear-cut (on an anodized aluminum plate) was made. To keep your laser in focus use always these parameters for the Z-axis.
Do not forget to measure the thickness of the material that you are going to cut or engrave and add it to the initial height of the 0 levels.
However, if you want to get even better results you may run another g-code (test2.gc) with smaller steps (0.1 mm).
The optimal focal range for a regular (long focal 3 element lens) in our experiments was 71.1 mm from the Z 0 (home) position.
As for this 10 watt diode laser you need to make a correction for the focal range to get the best engraving results: 71.1 mm – 13 mm (the difference between the laser height and the Z 0 position) – 0.5 mm (thickness of the material)= 57.6 mm; this is the range between the lens and the surface of the work material.
Learn more about laser lens pack
Learn more about laser beam focusing
focus test (g-code example for laser beam focusing)
Installation and adjustment of a 10W laser on 3D printers Anet A8 from Inkscape & Repetier-Host
When the module is installed and fastened 1-2 cm above the extruder nozzle, proceed with its connection. Here everything is simple, there’s no need to rack your brains (we did it for you). are We connect the laser control panel directly to the module itself, we connect the 12V power supply to it, and connect the fan power to the FAN 1 connector to the control board of the 3D printer.
Next, to the laser module itself, we connect the 12V power separately (external power supply). If everything is connected correctly, the fans start working; to run the laser just turn on the toggle switch on the control panel, and a laser beam will glow.
Now it is necessary to adjust the lens to focus the laser beam. To make the task easier I recommend that you draw a line, approximately 4-5 cm long, using Inkscape. Convert these lines into a G-code and load it into the Repetier-Host program.
To adjust the focus measure the height of the laser above the workpiece on the work table with a ruler. As a starting point, I use the bottom of the aluminum box of the module itself. Next, lift the carriage up about 9 cm and begin to rotate the lens until the laser beam appears as a sharp small dot on the workpiece where you are going to engrave the lines. Start engraving. The focus is correct if the engraved line is clear. If not so repeat this procedure until you get a clear thin line, using the control in the program Repetier-Host, raise the carriage to any desired height (this can be done to within 0, 0.1 mm) and start again for engraving.
Explore abilities with z axes
Do this procedure to the extent that we do not have a clear, even and thin line.
An independent test of Endurance laser lens pack
Focal range laser lens test. laser lens tests (PDF). Testing lens from different optical producers.
“As you may know, Endurance Lasers offers several different lens configurations which are now available in a “pack.” I now have the standard 3-Element, which came with my laser, and the G-2, G-7, and G-8 lenses which I received a couple of weeks ago. Now that I had them all, why not do a little experimenting?” by John Walker