Magnetic sensor

1. A magnetic sensor comprising: a magnetoresistive element whose resistance changes with an external magnetic field; and a support member configured to support the magnetoresistive element, wherein:

the support member has an opposed surface opposed to the magnetoresistive element, and a bottom surface formed of a flat surface located opposite the opposed surface;

the opposed surface includes an inclined portion inclined relative to the bottom surface;

in a specific cross section of the magnetic sensor perpendicular to the bottom surface, the inclined portion is inclined relative to the bottom surface at a first angle at a first position on the inclined portion, and inclined relative to the bottom surface at a second angle at a second position on the inclined portion, the second angle being smaller than the first angle;

an absolute value of a curvature of the inclined portion at the first position is less than an absolute value of a curvature of the inclined portion at the second position; and

the magnetoresistive element has a first edge and a second edge located at both ends of the magnetoresistive element in a width direction, and is provided on the inclined portion so that the first edge is located above the first position in the cross section.

2. The magnetic sensor according to claim 1 , wherein the magnetoresistive element is provided on the inclined portion so that the second edge is located above the second position in the cross section.

3. The magnetic sensor according to claim 1 , wherein the first position and the second position fall within a range from a third position on the inclined portion closest to the bottom surface in the cross section to a fourth position on the inclined portion farthest from the bottom surface in the cross section.

4. The magnetic sensor according to claim 3 , wherein:

the inclined portion is inclined relative to the bottom surface so that the first angle is a maximum and the second angle is a minimum within a range from the first position to the second position; and

the absolute value of the curvature of the inclined portion is minimized at the first position and maximized at a predetermined position other than the first position within the range from the first position to the second position.

5. The magnetic sensor according to claim 1 , wherein:

the opposed surface includes a convex surface protruding in a direction away from the bottom surface; and

the inclined portion is a part of the convex surface.

6. The magnetic sensor according to claim 1 , wherein:

the opposed surface includes a concave surface recessed toward the bottom surface; and

the inclined portion is a part of the concave surface.

7. The magnetic sensor according to claim 1 , wherein:

the magnetoresistive element includes a magnetic layer having a magnetization whose direction is variable depending on the external magnetic field;

the magnetic layer has a first surface and a second surface located opposite the first surface, and has a thickness that is a dimension in a direction perpendicular to the first surface of the magnetic layer; and

the thickness at the first edge is smaller than the thickness at the second edge.

8. The magnetic sensor according to claim 7 , wherein the thickness decreases toward the first edge from the second edge.

9. The magnetic sensor according to claim 7 , wherein the first surface and the second surface each have a shape long in a direction intersecting the cross section.