Abstract: An encoder includes a main body and a toothed encoding unit. The main body is made of material with magnetic permeability. The toothed encoding unit is made of material with magnetic permeability, and includes a toothed encoding set and a position toothed encoding set that are disposed on the main body. The toothed encoding set includes a plurality of recesses that are disposed in a first direction. Each of the recesses of the toothed encoding set extends in a second direction that is transverse to the first direction. The position toothed encoding set includes a plurality of recesses that are disposed in the second direction. Each of the recesses of the position toothed encoding set extends in the first direction.

Abstract: A magnetic encoder has an annular main body, a magnetic encoding unit and a position encoding unit. The main body is made of material with magnetic permeability, surrounds a central axis, and includes a first surface and a second surface opposite to said first surface. The magnetic encoding unit is disposed on the first surface of the main body, and includes a plurality of first and second magnetic poles, each of which is annular and is centered at the central axis. The annular position encoding unit is centered at the central axis, that is adjacent to the magnetic encoding unit, and that is disposed on the one of the first surface on which the magnetic encoding unit is disposed. The first and second magnetic poles are arranged in an alternating sequence.