I am working on a project where I want to expand the laser beam from a 10mW-30mW laser in a short distance. I attach a picture for illustration:
The idea is to use a first lens to expand the laser beam so that is attains a diameter of about 5cm in a short distance of about 5cm (angle of divergence around 30-45 degrees). Once the beam is expanded a second lens would be used to reduce the beam divergence to about 10 degrees. I have seen similar things using a double concave and a double convex lens, like an inverted Galilean system, but in those cases the laser beam after the second lens is collimated. In my case I would want to keep a beam divergence of about 10 degrees. Can that be done is a simple and inexpensive way like the inverted Galilean system?
The idea is to use a first lens to expand the laser beam so that is attains a diameter of about 5cm in a short distance of about 5cm (angle of divergence around 30-45 degrees). Once the beam is expanded a second lens would be used to reduce the beam divergence to about 10 degrees. I have seen similar things using a double concave and a double convex lens, like an inverted Galilean system, but in those cases the laser beam after the second lens is collimated. In my case I would want to keep a beam divergence of about 10 degrees. Can that be done is a simple and inexpensive way like the inverted Galilean system?