The laser is a single wavelength light source. With good coherence performance. In the field of scientific research and industry has a wide range of applications. Laser optics refers to optical elements and devices used in optical paths inside and outside the laser. For example, laser focusing mirrors, mirrors, beam expanders, laser cutting heads. In order to allow small partners can intuitively understand the laser focus and collimation of the concept.

Application 1: The focus of the collimated beam (metal laser cutting machine )

Firstly, let’s look at a very common application that focuses the laser beam onto a small focus. We have a laser beam with a radius of y1 and a divergence angle of θ1. It is focused by a lens with a focal length of f. As shown, we have θ2 = y1 / f. The law of optical invariants (y2θ2 = y1θ1) tells us that the product of the radius of the focused spot and the divergence angle is constant, so y2 = θ1f can be obtained, in metal laser cutting machine.

Application 2: The alignment of the light from the point source

Secondly is to align light from a very small light source.  This light source is usually referred to as a point source. But in reality there is no absolute point of the light source, any light source has a certain size, need to be considered in the calculation. The point source radius in is y1 and the maximum emission angle is θ1. If the outgoing light is collimated with a lens with a focal length f, the radius of the obtained collimated beam is y2 = θ1f and the divergence angle is θ2 = y1 / f, in metal laser cutting machine.

Application 3: Beam expansion

Thirdly, it is often necessary to expand the laser beam. To achieve this function, at least two lenses are required. Most laser beam expanders are galvanized and are made up of positive and negative lenses. Due to the low expansion factor, simple, compact structure is widely used, beam expander by enlarging the laser beam to achieve a smaller focus spot in metal laser cutting machine.

Application 4: Focus of large size light source

This application is similar to optical imaging, unlike the collisions and focusing discussed above. A typical example is the imaging of a fluorescent sample to the CCD camera. The optical structure shown in Figure 4. A larger size of the light source, radius y1, is placed at a distance from the lens s1, the lens focal length is f, the aperture is R.