Abstract: In an IPM rotor, a first core sheet has a first sheet hole forming a part of an accommodation hole. The first sheet hole has an edge portion having a flat spring portion which is bent by a magnet through insertion of the magnet into the accommodation hole. A pair of recesses forming a clearance with respect to the magnet are formed at both side portions of the flat spring portion of the edge portion of the first sheet hole. A size of the clearance is set based on a relationship between a magnitude of a pressing force of the flat spring portion on the magnet and variation in pressing force.

Abstract: A surface emitting laser includes a substrate, semiconductor layers on the substrate, a light transmitting window configured to transmit laser light from the semiconductor layers, a first electrode pad, a second electrode pad, a first dummy pad, and a second dummy pad, wherein the first electrode pad, the second electrode pad, the first dummy pad, and the second dummy pad are disposed on the semiconductor layers at a place different from the light transmitting window, and wherein the substrate is classified into first through fourth regions by a straight line extending in a first direction and a straight line extending in a second direction perpendicular to the first direction, the first electrode pad being situated in the first region, the second electrode pad being situated in the second region, the first dummy pad being situated in the third region, and the second dummy pad being situated in the fourth region.