A fat removal device includes a screen which includes passages through which fat can be extruded, to be cut or melted away from the surface of an internal organ. Each layer has a constant axial angle, and an optical axis of each layer inclines with respect to the x axis in an xz plane. A wide band-gap JFET region having the first conductivity type is provided between the first and second well regions. The other manner is to pulse a first acoustic element the pulse a second acoustic element after a delay equal to the amount of time it takes for the first pulse to reach the face of the second acoustic element. A hollow adjusting block is mounted in the outer sleeve and has an outer threading for threadedly engaging with an inner threading of the outer sleeve.