There is provided a characteristic adjustment method for an image forming apparatus
that is provided with a multi-electron source in which a plurality of electron-emitting
devices are electrically connected by wiring and arranged on a substrate and a
fluorescent member for emitting light by irradiation of an electron beam, the method
including: a measurement step of dividing a display portion of the image forming
apparatus into a plurality of areas and measuring light emitting characteristics
of at least one or more of the electron-emitting devices in the respective divided
areas, and a shifting step of shifting the light emitting characteristics of the
electron-emitting devices in the divided areas to individual characteristic target
values by applying a characteristic shift voltage to the electron-emitting devices.
