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Selection of scanning lens type of laser marking machine


F-theta scanning lens (also known as: lens, lens, field lens, objective lens, etc.) is a kind of focus flatness item that is designed to make the pixel height and the scanning angle satisfy a certain relationship, and the scanning angle Certain linear relationship, the formula is: y = F-theta * θ (θ is the deflection angle of the galvanometer).


Its main features are:

(1) The imaging is within a certain plane range, the pixels are consistent and not deformed, and the pixel difference is small.
(2) Plane marking within a certain range, corresponding to the galvanometer scanning speed within a certain speed

Conventional laser marking machine (laser engraving machine, laser coding machine, laser engraving machine, etc.) selection, lens selection has certain rules.

According to the type of laser, this is based on the selected laser wavelength:

1. 1064nm wavelength lens;
2. 532nm green wavelength lens (450nm blue wavelength lens is not commonly used);
3. 355nm ultraviolet wavelength lens (266nm deep ultraviolet wavelength lens is not commonly used); 

The above three types are conventional solid-state laser lenses; 




4. 10.2μm wavelength CO2 lens;
5. 10.2μm wavelength CO2 lens;
6. 9.3μm wavelength CO2 lens; 

The above three types are conventional gas laser lenses;

Choose a lens according to the number of lenses:

1. Conventional CO2 lasers generally choose a single lens group (the main material of the coating process on the lens is zinc selenide, and the material is very expensive). Only special processes will choose double lens groups and triple lens groups;
2. Conventional solid-state lasers generally choose double lens groups (simple coating process, conventional price), and those with special processes will choose three lens groups; 

Selection of marking format:

Many customers always think subjectively that the larger the scanning format of the scanning lens, the better, but this is not the case.
The main reason is that the larger the marking area, the longer the focal length, the larger the focusing spot, the greater the distortion, the laser spot is not delicate enough, and the laser single-point power energy density is also smaller. Products are not marked or have no depth, but can not meet the requirements for use.



Therefore, to choose the most important one that suits you, there is no need to choose a wider range of scanning lenses, thereby increasing your own cost.
F-theta scanning lens, also known as lens, lens, field lens, objective lens, etc., mainly plays a focusing role in laser marking machine, laser coding machine, laser engraving machine, laser engraving machine and other equipment.