A vibrating device includes a vibrator having a dust-screening member which is shaped like a plate as a whole and has at least one side that is symmetric with respect to a symmetry axis, and a vibrating member secured to the dust-screening member and configured to produce, at the dust-screening member, vibration having a vibrational amplitude perpendicular to a surface of the dust-screening member, and a hold and support member configured to hold and support the vibrator to a fixed member. The hold and support position by the hold and support member is arranged at position along a circle or ellipse concentric to the centroid of the vibrator such that peak ridges of the vibration having a vibrational amplitude perpendicular to the surface of the dust-screening member form closed loops.