What is the focal length? Focal length is the distance from the optical center of the lens to the focal point of light gathering when parallel light is incident. To put it simply, focal length is the distance from the focal point to the center point of the mirror. You can read this article "About the focal length and range of YAG and CO2 field lens" article illustrates the focal length of various types of field lens. Here's how:
The first method: continuous light test
Draw a square or circle of about one centimeter on the marking software, and fill it conventionally. Adjust the laser energy to a relatively large value in the laser setting parameter column, use the low frequency as much as possible, and then select continuous marking, and laser project on the product surface. Place a block such as a metal business card at the position, continuously mark the light, and shake the Y axis up and down until the laser is applied to the metal business card with the strongest energy, the clearest sound, and the brightest color, which is basically the focal length. Test a few more times to find the right focal length.
After finding the focal length, we can use a ruler to measure the distance from the down lens to the surface of the object. Use this distance as a fixed value. The next time you mark the same item, you only need to take out the ruler, so that the height of the galvanometer to the surface of the item can reach this value again.
The second method: red light point value method
It can be positioned by configuring additional red light. This method requires the device to have this hardware configuration. Install one or two oblique red lights next to the galvanometer or galvanometer. Using some principles of a right-angled triangle, use a fixed right-angled edge and two overlapping hypotenuses. Find the other right-angled side of the focal length. You only need to shake up and down until the two red light points coincide to quickly find the focal length. Although this method is convenient and fast, it requires equipment to have this device.
Gold Laser is currently using dual red light positioning device to quickly find focus