How To Use Different Focus Lenses - Finding the Perfect Lense for Every Material

[@maxpedersen2464]

Perfectly explained. Great stuff. Can you do a video on lens choice for different thicknesses of acrylics?

[@TrotecLaserEngraving]

Hey Max, thanks for your feedback. We'll put the video about lenses for acrylic cutting on our todo list.

[@ivangutowski]

Very, very clear and helpful.. Great examples thank you.

[@TrotecLaserEngraving]

Hey, thanks Ivan. :)

[@johndavis415]

Thanks so much, I have been struggling with this for a while and you made it very clear.

[@TrotecLaserEngraving]

Hi John, that's great. We're glad that this was helpful. And if there's any other topic you want us to cover, let us know.

[@MrTHEORIGINALICEMAN]

It is refreshing to get a thorough explanation without the 30 extra minutes of useless off-topic information.

[@TrotecLaserEngraving]

Hey thanks for this feedback. We're trying to offer a mix of different video styles, depending on the topic. For explaining how lenses work, we thought a more fact-based approach would fit better.

[@Ckoraybingol]

It is very well explained, thank you. I will suggest these videos to our graduate architecture students. Unfortunately, we don't have a Trotec Laser at the faculty, if we had one then they might see the quality differences better.

[@TrotecLaserEngraving]

Hey thanks, Cemal. That means a lot to us :) If you got ideas for other laser-related topics that are interesting for your students, let us know. And in case you want to swap your laser for a Trotec in the future, there are special deals for educational institutions, that could be interesting for you.

[@Adi-S]

I recently purchased a Gravograph LS100 laser. I wish they would have videos as good as yours. There is a lot of good material from Trotec on KZbin. I feel kind of guilty using a competitors laser and learning from your videos. So, thanks a lot and keep up the great work!

[@TrotecLaserEngraving]

Thank you very much for your compliments. Of course we'd be delighted if your business is going well and you can use our videos for a Trotec laser one day. :)

[@mkelay43]

am sooooo happy with this explanation

[@serkanozkan8793]

thanks. Learned alot.

[@iloveaviation-burgerclub-a8145]

As I got it right you did not adjust the focus when engraving Al to the focal length of the 2nd and 3rd lense? If this is done the engraving should look exactly the same on all three specimen. Right? What are the possibilities to get a smaller focus point? This would be the way to increase resolution, increase speed by having a more concentrated spot and you will be able to cut deeper with a 4" one. What can be done to get a smaller burn point diameter? Mine is about .068mm DIA in optimum setting. I really would like better resolution also when production time increases by a smaller line gapping. Thanks guys.

[@TrotecLaserEngraving]

Hi! Thanks for your question and interest - you can find a detailed description about our focus lenses and the optimal use of them for reaching perfect results here: www.troteclaser.com/en/laser-machines/laser-accessories/focus-lenses/. If you require any further info on this topic, please contact us: www.troteclaser.com/en/contact/

[@KevinHigby]

Why does a longer focal length correlate with a larger spot size? I would have thought they all converge to a point (diameter 0) before diverging. Is this due to Raleigh scattering?

[@TrotecLaserEngraving]

Regarding point (diameter 0): A wave cannot be focused to a point. The beam waist increases with increasing focal length and wavelength. Waist is typically 10-20 times the wavelength. Please find more information here: www.troteclaser.com/en/knowledge/tips-for-laser-users/selection-of-the-right-lens/

[@dennismadderra3916]

The graphic at 1:40 is incorrect. Focal length is from the center of the element, not the leading edge to the focal plane. I know it doesn't mean a bunch here, but the same term in photography has significant importance.

[@TrotecLaserEngraving]

Hi, thanks for your input, you are very keen-eyed. You are right, the line is inaccurate and will be corrected with the next revision of the video.

[@MarshallArtsPics]

What were the speeds/powers used? Does the 4" lens need more power to cut through the same material as a 1.5" or 2.5"?

[@TrotecLaserEngraving]

Hello Colleen, thank you for your questions. The parameters differ according to the materials you're processing with the laser. The more delicate and detailed the graphics are, the smaller the lens should be. For cutting thick materials, lenses of maximum size are recommended. For detailed information please see our FAQ page: www.troteclaser.com/en/knowledge/tips-for-laser-users/selection-of-the-right-lens/.

[@trinhquanghung8406]

Very well explained and informative. I'm searching for a focus lens for a 500 W fiber laser source but dun't know whether it needs to be water-cooled and how to do so. Do you have any suggestion?

[@TrotecLaserEngraving]

Hi, unfortunately we're not selling 500W Fiber lasers. We are sorry, but we are not the experts to answer that question.

[@TylerHarney]

What kind of laser power wattage do you need to use a 4" lens?

[@TrotecLaserEngraving]

Hi Mr. Harney, the parameters (especially speed and power) are depending on the material you intend to engrave/cut and the expected outcome (color change, depth of engraving). The 4" lens has a spot size (diameter) which is twice as large as the spot size of a 2" lens. Energy density compared between 2" and 4" is 1:¼ --> you have to adapt your parameters (speed & power) to compensate this much lower energy density. Your Trotec Team

[@bosrensen7500]

Will a 4" focus lens be able to cut deaper materiale with the same power than the other 2 lens types ?

[@TrotecLaserEngraving]

Hi Bo, basically yes. A larger lens is able to cut through thicker materials than a smaller lens. But the laser power of the machine needs to be high enough to cut through this material, too. We'd need to look into your case in detail to give you a precise answer. Let me know, where you're from. Then I can give you the contact details of your local laser application engineers. They can support you by testing your material on our lasers (free of charge, of course).

[@Steppinonshii]

excellent explanation

[@TrotecLaserEngraving]

Glad you like it!