MIRROR DEVICE

A mirror device (1) includes: a mirror (2) having a rotation shaft (21) and a reflecting surface that reflects display light; a support portion (34) having a cylindrical shape, having a base end (34c) fixed and a tip end (34b) being a free end, and configured to rotatably support the rotation shaft (21); and a motor (4) that pivots the mirror (2), in which the rotation shaft (21) is inserted into the support portion (34) while spreading the support portion (34) outward in a radial direction, and is slidably supported by the support portion (34).