If we need to mark large-format products but find that the laser marking machine can’t mark so large, how to do?
In fact, this time replacing a field lens can solve it.
A field lens, also known as a flat-field focusing lens, scanning lens, or F-theta lens, is a necessary accessory for a laser marking machine. The field lens is to reflect and focus the laser beam so that the laser hits the appropriate position.
The field lens configured by the laser marking equipment mainly includes 70×70, 110×110, 170×170, 220×220, 300×300, etc. according to the marking range; according to the wavelength: 1064nm field lens(fiber field lens), 10.6um field lens (CO2 field lens), 532nm field lens (green light field lens), 355nm field lens (ultraviolet field lens).
What is the function of laser marking machine field lens?
Improves the ability of the edge beam to hit the detector.
It can also homogenize the non-uniform illumination on the photosensitive surface of the detector.
In the same primary optical system, additional field lenses will reduce the detector area.
If the same detector area is used, the field of view can be enlarged and the incident flux can be increased.
Therefore, if the laser marking machine wants to expand the marking range, it is necessary to replace the field lens.
When purchasing, you cannot fully pursue the large field lens.
Because the larger the size of the field lens, the larger the focal length and working distance of the corresponding field lens. The longer the focal length, the larger the laser-focused spot will be, the focus will not be fine enough, and the distortion will increase, which will result in very shallow marking depth and thick lines, not conducive to precision processing.
The selection of the field lens is determined according to the configuration of the laser marking machine. For example, for a 20W fiber laser marking machine, it is recommended that the field lens should not exceed 170×170mm. The larger the lens of the laser, the greater the consumption of the laser. The quality of the beam is not good, and the marking effect is also reduced.