  We demonstrate an ultrathin and semitransparent anisotropic and spin Hall
magnetoresistance sensor based on NiFe/Pt heterostructure. The use of
spin-orbit torque effective field for transverse biasing allows to reduce the
total thickness of the sensors down to 3 - 4 nm and thereby leading to the
semitransparency. Despite the extremely simple design, the spin-orbit torque
effective field biased NiFe/Pt sensor exhibits level of linearity and
sensitivity comparable to those of sensors using more complex linearization
schemes. In a proof-of-concept design using a full Wheatstone bridge comprising
of four sensing elements, we obtained a sensitivity up to 202.9 m{\Omega}/Oe,
linearity error below 5%, and a detection limit down to 20 nT. The
transmittance of the sensor is over 50% in the visible range.
