How does the objective lens of the laser marking machine work?
The expanding part is a negative lens, ie small focus lens, which realizes beam expansion and moving zoom, the focusing lens is composed of a group of positive lenses. The galvo mirror is mirror in the galvanometer system.
The laser beam first passes through the laser marking focusing system to form a condensing beam, and then is deflected by the scanning system to form a scanning point on the working surface, which is the scanning of the rear objective lens of the laser marking machine. When the static focusing method is used, the focusing surface of the laser beam after passing through the scanning system is a spherical surface. If the center of the working surface is the tangent point between the focusing surface and the working surface, the farther away from the center of the working surface, the distance from the scanning point on the working surface will be. The larger the focus error is.
If the defocus error of scanning in the whole working surface is controlled within the range of the depth of focus, the static focusing method can be used. For example, in a UV-curing rapid prototyping equipment with a small working surface, the long focusing method can ensure that the defocus error of the scanning point in the entire working surface is within the range of the depth of focus under the condition that the focused spot is small. In the selective laser sintering rapid prototyping equipment, the C02 laser is generally used, and the wavelength is long, and it is difficult to obtain a large depth of focus with a small spot, so the dynamic focusing method is generally used when the scanning width is large.
Fiber Post objective scanning system supplier
The dynamic focusing system of the laser marking machine is generally composed of a movable focusing mirror and a stationary objective lens. The objective lens amplifies the adjustment effect of the focusing mirror, so as to control the focusing spot of the scanning point within a certain range in the entire working surface. The post-scanning method of the objective lens of the laser marking machine can perfectly control the laser beam to work, and the effect is very accurate.