Laserengraving Wiki:Wanderland90/How Does Laser Engraver Work?

After years’ improvement, diode laser engraver and cutter has developed from a DIY tool into a professional tool for commercial and industrial production. The reasoning behind this is that diode laser cutting and engraving technology works for multiple materials, offers decent cutting and engraving performance, saves lots of money for initial investment and is much easier to use. To realize its full potential, it’s really important to understand how laser cutters & engravers work.

How does diode laser work? – simple answer
Semiconductor diode is the core element of any diode laser. A diode laser is a p-n junction diode that consists of one p-semiconductor and n-semiconductor. And it is with two ends, one with a high-reflection blocker and the other with the partially reflective end. Basically, the diode laser is like a lighting LED to amplify light with reflectors. Once powered on, photons generated would be amplified while traveling forward and backward between two lenses until laser oscillation.

How does diode laser work? – comprehensive answer
When laser device is powered on and electrical current going through the diode, the flow of electrons would go through the p-n junction.These electrons combine with holes on the other side of the junctions, in turn releasing excess energy in the form of photons. These photons would hit the atoms, causing more photons to be released. As the current increases, more electrons would enter the depletion zone and cause more photons to be emitted. Eventually, some photons would be reflected back along their original path. The reflected photon is again reflected from the other end of the junction. This movement of photons from one end to the other is continuous multiple times. During the movement of photons, atoms will release more photons due to the avalanche effect. This process of reflecting and generating more and more photons produces a very intense laser beam. Each photon produced in the emission process of is the same energy level, phase relationship and frequency as other photons. Therefore, the emission process gives a laser beam of a single wavelength.

In more complex applications, several semiconductor diodes can be stacked together. The multiple beams from these diodes can be focused into a single beam, making the output considerably more powerful. One example is the TS3 laser cutter & engraver which uses two LDs and LD+FAC+C-lens technology to get 0.08mm laser spot with stronger penetration strength. The most important factors to tell the performance of any diode laser are the working power of the laser head, the size of the laser spot and the laser beam angle of the fast and slow axis. The LD+FAC+C-lens technology makes TS3 and other TT series laser cutters & engravers stand out among their competitors. Twotrees machines use two independent 5W laser diodes, combine and compress their lasers into a single 0.08mm laser spot. This powerful laser spot enables more materials to be processed and gets better cutting & engraving results. Compared with most other devices in the market which use LD+C-lens technology, TwoTrees’ machines are with smaller beam spots, optimized laser beam angles for both fast and slow axis to get clearer and smoother cuts and engraves.

How does a laser cutter & engraver work step by step?
Laser cutting and engraving technology use design files to direct the powerful laser beams to melt, burn, vaporize away materials to achieve marking, engraving and cutting functions.

The cutting and engraving process is as simple as printing.


 * Step One: Get a picture or design file you want to be processed by the laser cutting and engraving machine.
 * Step Two: Then install software and customized settings to guide the laser path according to the design file.
 * Step Three: At the push of a button, the motherboard would send a command and signal to the laser header.
 * Step Four: The laser header would then move left and right along the X-axis and X-axis would move forward and backward along the frame in accordance with the design file. If your cutting and engraving machine is with rotary axis, it would start rotation synchronously to get better performance for curved surfaces.

To start cutting & engraving, a few preparations needs to be done:


 * Install proper software: for consumer desktop laser cutter & engraver, LightBurn and LaserGRBL are the two most popular software in the market.
 * Find amazing ideas for cutting & engraving: you might get inspiration from the post “Top 13 Laser Cutting Design Files Download Websites”
 * Choose the right cutting & engraving machine for your projects: Here are some tips “Which laser cutter & engraver to buy?”.
 * Cutting & engraving with the right materials: Some materials you need to avoid are listed here “Which laser cutter & engraver to buy?”.

1. Rotary Roller
A rotary roller is considered as the 4th axis for a laser cutter or engraver except for the general X-axis, Y-axis and Z-axis. Rotary attachment is an important accessory specially designed for processing curved objects. Usually, a fixed focal distance between the laser head and object surface is set for the greatest penetration force while cutting and engraving. It works for most objects with a flat surface as focal distance would remain the same as preset settings.

However, for curved objects, the focal distance would be different in different positions which would lead to different cutting and engraving depths. The purpose of using a rotary roller is to use a rotary axis to replace the general Y-axis as it would keep rotating to make sure every processed point gets the same fixed focal distance while a curved object is cut or engraved. To enable users to cut and engrave both flat and curved objects, TS3 is designed with a Y-axis toggle switch to change the processing model with a single click. It saves lots of trouble of changing cutting and engraving platforms and makes TS3 a great tool for users of all levels.

2. Cutter & Engraver Honeycomb Bed
One most frustrating concerns for desktop DIY laser cutters and engravers is that the devices are usually delivered without any cutting or engraving bed. Users tend to put it right on the desk  (maybe with some pads) for cutting and engraving, there is a big chance he might burn the desk or leave terrible scars and trails on the desk by chance. That’s why a honeycomb bed with a metal pad is provided for the TS3 laser cutting and engraving machines. Other uses for honeycomb bed includes structural support, energy absorption, light diffusion, airflow and much more.

3. Ventilation System & Extraction Fan
For most consumer DIY laser cutters and engravers, there is no ventilation and extraction system at all. An enclosed laser cutter & engraver for home use with decent ventilation and extraction system would be really great options to consider if you are planning to get one. Instead of using a pipe or extraction fan to exhaust smoke out of the enclosed housing of the laser cutting machine, TS3 uses internal circulation for smoke purification. The system is with two extraction fans and a pad with active charcoal. When cutting & engraving starts, the extraction fans start to work and force smoke or dust flow into the purification container with active charcoal pad. The process goes on continuously until cutting and engraving are completed.

Conclusion
Knowing how does a laser cutter & engraver works give you competitive advantages while choosing the right device for your demands. It also saves lots of time and money on testing different options. If you have any questions or doubts, please feel free to leave a comment and discuss with us.