The working range of the beam, a function of wavelength, diameter of the unfocused beam, and focal length of the lens. To achieve a small diameter spot size, and thus a high power density, a short depth of field must be accepted.
Diffuse Reflection
A change in the spatial distribution of the laser beam by virtue of its reflective interaction in many directions by a non-specular (non-mirror like) surface or other reflecting medium.
Divergence
The angle at which the laser beam spreads in the far field; the bending of rays away from each other, as by a concave lens or convex mirror.
Divergence
The angle at which the laser beam spreads in the far field; the bending of rays away from each other, as by a concave lens or convex mirror.
Duty Cycle
The length of time the laser beam is actually cutting, drilling, welding, or heat-treating, as compared to the entire work cycle time.