If you are a fan of CO2 lasers, you know that precision is key. Sometimes, however, getting that precision can be challenging, especially when trying to line up your engraving with your desired marking location. That's where beam combiners come in. Let's start with a little breakdown of what they are and then move on to 'how to'...
A beam combiner is a device that allows you to combine a laser beam and a visible light beam, such as a red dot sight. This combination allows you to easily see where your laser beam will land without having to guess or adjust your laser head for each new engraving.
To understand how a beam combiner works, it's important to understand how a laser beam is generated. In a CO2 laser, a high-voltage electrical discharge is sent through a gas mixture, typically a mixture of carbon dioxide, nitrogen, and helium. This discharge excites the gas molecules, causing them to emit light. This light is then amplified as it passes through a series of mirrors, creating a focused and intense beam of light.
A beam combiner works by using a partially reflective mirror, which reflects a portion of the laser beam and allows the remaining light to pass through. The red dot sight is positioned behind the partially reflective mirror so that it can reflect back into the path of the laser beam. This creates a superimposed image of the red dot on the laser beam, allowing you to see exactly where the laser beam will land.
One of the main advantages of using a beam combiner is that it eliminates the need for manual adjustments of the laser head for each new engraving. This can save you a lot of time and effort, especially if you frequently change engraving locations. Additionally, using a red dot sight can help you achieve greater accuracy and precision in your engravings, especially when working on detailed or intricate designs.
When selecting a beam combiner for your CO2 laser, there are a few key considerations to keep in mind. First, it's important to ensure that the beam combiner is compatible with your laser model. Additionally, you'll want to look for a beam combiner that is easy to install and adjust. Some beam combiners come with built-in adjustments for aligning the red dot sight with the laser beam, which can be very helpful.
It is important to note that when adding a beam combiner to your laser, you will typically see an output power reduction of anywhere from 2%-8%. Any more than that and you should not use the beam combiner or check to make sure there is not an inaccuracy in alignment or that you are not using the correct mirror(s). To get a really good breakdown of how to analyze and setup a beam combiner, watch this video from Russ Sadler:
Using a beam combiner with a red dot sight is an effective way to achieve greater precision and accuracy in your laser engravings. By allowing you to easily see where your laser beam will land, a beam combiner can save you time and effort, while also helping you to achieve better results. When selecting a beam combiner for your CO2 laser, be sure to choose one that is compatible with your model and easy to install and adjust. With the right beam combiner, you'll be well on your way to achieving the perfect laser engravings every time.