Heating device and method of manufacturing magnetic recording medium

A method of manufacturing a magnetic recording medium comprising forming a magnetic layer on a workpiece having a disk shape with a hole in a center and having a pair of main surfaces opposite to each other, the method comprising after the forming:

• heating the workpiece by irradiating the workpiece with light,
• wherein the heating is performed by irradiating at least one main surface of the pair of main surfaces of the workpiece with light by an irradiating part including a plurality of light emitting elements on a surface of the irradiating part facing the at least one main surface of the workpiece,
• in a case where a plane including the main surface of the workpiece is defined as an irradiation-target surface, the irradiation-target surface includes a first region in which the hole of the workpiece is formed, a second region surrounding the first region from an outer side, and a third region extending from an outer periphery of the second region to an outer periphery of the workpiece, and
• in a case where a radius of the hole is defined as Ru, a radius of the outer periphery of the workpiece is defined as RW, a radius of the outer periphery of the second region is defined as 0.30RH+0.70RW, and a radius of an outer periphery of the third region is defined as RW, and an average amount of irradiation of the light on the first region is defined as I1, an average amount of irradiation of the light on the second region is defined as I2, and an average amount of irradiation of the light on the third region is defined as I3, I1/I2 is 1.00 or less, and I3/I2 is 0.90 or more and 1.50 or less.