Since the microscope objectives previously discussed are achromatic, on-axis part viewing through the laser objective is possible. Simultaneous focus of the laser beam and part image can be obtained, provided that the eyepiece optics and viewing position are carefully chosen. Such on-axis viewing schemes provide very high magnification viewing of the workpiece during processing. This can be very valuable in aligning laser features to preexisting features on the part. Visible light mask illumination can also be employed to generate a visible image of the target area on the part. Thus, alignment of part features with the laser beam can be performed precisely prior to firing the laser.
Direct process site viewing using Schwarzschild projection lens
Advantages of microscope systems
Disadvantages of microscope systems