How to split the laser?

Question

Physics

1. How to split the laser beam, and then direct the split beam to one point? What is the task: you need to sinter the powder (3D printing) from different sides, for this you need to divide the beam into several beams, and then send them to one point. The distance between the points is 20-30 cm. The laser is guided by movable mirrors, and not by the movement of the head on the rails. Fiber. Preferably options with links to where you can buy.
2. Is it possible to move the laser outside the camera and how? There is a chamber in which the temperature (IR heating pad) and vacuum. The laser would like to be done outside the camera. How can I do that? That is, the chamber wall itself is a piece of steel a centimeter thick, in order to hold a vacuum, it is necessary to make some holes in it, plug them with glass and let a beam through them, but how is this done correctly?

Answer 1

1. What was advised in the comments - a beam splitter cube (High-Power, Laser Line, Polarizing Beamsplitter Cube) - a practical and working option for laser light. It has a set of characteristics - physical size, operating wavelength range, polarization - which, of course, must be selected for specific conditions. The alternative is the same, but in the form of a plate. Questions about biases and errors are not very clear. Refraction occurs inside the cube, and the glass-air interface intersects at a right angle. Reflection and scattering are kept to a minimum in professional solutions. 3 cubes will divide one beam into 4, and then mirrors - this is the simplest geometry of light reflection from a mirror. Naturally, all optical elements must be placed, fixed, and adjusted.
2. We make a hole, cut the thread, screw the glass in the frame. Cheap angry option - make a hole, paste the glass. Of course, I would like the laser beam to cross the glass at an angle close to a straight line. The conditions inside the chamber impose restrictions on the design, namely on the adhesive, the strength of the glass, the strength of the adhesive bond. If there is a lot of hard dust inside, then the glass will be bad, scratched, you can change the glass, or you can move it outward from the chamber wall through the adapter / gut so that the dust does not fly near the glass.
3. I would start looking at specific options in thorlabs.com (there is a lot of information available on the site, a kind of guide) or standa.lt.