Water treatment device

A disinfection device including a pipe, an ultraviolet (UV) laser, a beam steering device and a transparent layer, the pipe including,

• an inlet and an outlet, wherein:
• the pipe includes a tapered section adapted to receive a fluid flowable through the pipe;
• the tapered section is adapted to be exposed to a focused laser beam for disinfection of the fluid;
• the UV laser is located at a smaller diameter end of the pipe and is adapted to project the focused laser beam towards a larger diameter end of the pipe;
• the focused laser beam is adapted to project through and/or off the beam steering device and through the transparent layer at a plurality of angles in a cycle in which the focused UV laser is adapted to move in a pattern that achieves statistically full coverage or full exposure of the fluid that flows through the tapered section;
• the beam steering device is adapted to steer the laser beam at the angles such that a profile of the focused laser beam projects through part or all of an inner profile of a point along the tapered section in the cycle, the inner profile of the tapered section being a 2-dimensional profile taken through a cross-section of the pipe;
• the pipe is adapted to receive a fluid that enters the inlet, passes through the pipe and exits through the outlet;
• one of the inlet or the outlet is located at the smaller diameter end of the pipe and the other of the inlet or the outlet is located at the larger diameter end of the pipe;
• and
• wherein, the pipe includes fins or channels in the tapered section, the UV laser projecting the focused UV beam towards the fins or channels in an alignment parallel to the fins or channels and to the flow of fluid through the pipe.