A processing apparatus is a processing apparatus that irradiates a surface of an object with processing light to process an object and is provided with: a light irradiation apparatus that emits first processing light to form a first irradiation area on the surface and emits second processing light to form a second irradiation area, at least a part of which overlaps with the first irradiation area, on the surface, and has a change member that is configured to change a state of an overlap between the first and second irradiation areas.

A system for welding a first component to a second component. The system includes a first laser head configured to emit a first laser beam and be movably disposable on a first side of the first component. The system further includes a second laser head configured to emit a second laser beam and be movably disposable on an opposing second side of the first component. The system further includes a controller configured to independently control a first power of the first laser beam and a second power of the second laser beam. The controller is also configured to independently and simultaneously control movement of the first laser head and movement of the second laser head relative to the first component.

A processing apparatus is a processing apparatus that irradiates a surface of an object with processing light to process an object and is provided with: a light irradiation apparatus that emits first processing light to form a first irradiation area on the surface and emits second processing light to form a second irradiation area, at least a part of which overlaps with the first irradiation area, on the surface, and has a change member that is configured to change a state of an overlap between the first and second irradiation areas.