Image output apparatus, output image control method and output image control program

An image forming apparatus for forming a toner image according to an image signal, the apparatus having a function to manipulate characteristics regarding qualities including an optical density of the toner image formed by said apparatus through adjustment for controlling said qualities for a specific level in relation to environmental states including an environment in which the apparatus is placed and changes over time in performance characteristics, the apparatus comprising:

• an electrifier configured to uniformly charge the surface of a photo conductor on which an electrostatic latent image that is an electrostatic image is formed, to a bias voltage of an arbitrary level within a specific range;
• a laser output unit configured to form said electrostatic latent image according to the image signal on said photo conductor surface by exposing said uniformly charged photo conductor surface with an arbitrary exposure rate within a specific range;
• a developing unit configured to develop said electrostatic latent image on the photo conductor surface using toner at a second bias voltage within a specific range according to said bias voltage of an arbitrary level so as to form said toner image on said photo conductor surface;
• a sensor configured to detect the optical density of said toner image formed on said photo conductor surface in a reference pattern, said reference pattern being an image used as a reference for obtaining indices;
• a database configured to store representative data indicating a relationship between the values of said bias voltage and exposure rate that are the manipulated variables with said electrifier and laser output unit and the detected density that is a detected value of the optical density of the toner image in said reference pattern used as an index of said qualities for predetermined representative manipulated variables in a specific environmental state;
• and
• a manipulated variables adjustment configured to obtain said manipulated variables adjusted for controlling said qualities for a specific level by comparing the data indicating the relationship between said values for the manipulated variables determined or calculated at the time in said environmental state at the time with representative data stored in said database in the course of controlling said qualities for a specific level,
• and wherein said manipulated variables adjustment unit corrects the data in said database based on the data indicating the relationship between said values in said environmental state at the time when necessary in the course of controlling said qualities for a specific level to obtains said new manipulated variables.

An output image control method for controlling, with an image output apparatus being capable of image output and having a function to manipulate characteristics regarding qualities including an optical density of an image outputted by the apparatus, the qualities for a specific value in relation to environmental states including an environment in which said apparatus is placed and changes over time in performance characteristics, the method comprising the steps of:

• storing representative data indicating a relationship between manipulated variables and controlled variables for predetermined representative manipulated variables in a specific environmental state, said manipulated variables being variables used for manipulating characteristics regarding said qualities, said controlled variables being indices of said qualities in a reference pattern that is an image used as a reference for obtaining the indices;
• and
• obtaining new manipulated variables adjusted for controlling said qualities for a specific level by comparing the data indicating the relationship between said variables for said manipulated variables determined or calculated at the time in said environmental state at the time with representative data stored in said database in the course of controlling said qualities for a specific level,
• and wherein the step of obtaining said new manipulated variables is a step of obtaining said new manipulated variables after the data in said database is corrected based on the data indicating the relationship between said variables in said environmental state at the time when necessary.