Image forming apparatus that controls image formation condition

An image forming apparatus comprising:

• an image carrier,
• an image forming unit configured to form, on the image carrier, a detection image that has one or more lines in a direction different from a movement direction of a surface of the image carrier;
• a light emitting unit configured to emit light toward the image carrier on which the detection image is formed;
• a light receiving unit configured to receive reflection light of the light emitted by the light emitting unit, and output a detection signal that corresponds to an amount of received reflection light including a specular reflection light component;
• a detection unit configured to output, as an output signal, a signal that corresponds to a difference between a detection signal value that corresponds to an amount of reflection light received from a first position at which the detection image is formed and a detection signal value that corresponds to an amount of reflection light received from a second position different from the first position;
• and
• a control unit configured to control an image formation condition related to density of an image to be formed, based on a peak value of the output signal of the detection unit,
• wherein the detection unit outputs, as the output signal, a signal that corresponds to a difference between an average value of a first section and an average value of a second section that is separated from the first section by a predetermined amount of time.

An image forming apparatus comprising:

• an image carrier,
• an image forming unit configured to form, on the image carrier, a detection image that has one or more lines in a direction different from a movement direction of a surface of the image carrier;
• a light emitting unit configured to emit light toward the image carrier on which the detection image is formed;
• a light receiving unit configured to receive reflection light of the light emitted by the light emitting unit, and output a detection signal that corresponds to an amount of received reflection light including a specular reflection light component;
• a detection unit configured to output, as an output signal, a signal that corresponds to a difference between a detection signal value that corresponds to an amount of reflection light received from a first position at which the detection image is formed and a detection signal value that corresponds to an amount of reflection light received from a second position different from the first position;
• and
• a control unit configured to control an image formation condition related to density of an image to be formed, based on a peak value of the output signal of the detection unit,
• wherein the image forming unit is further configured to, during printing, change the image formation condition related to density while forming the detection image between images formed on the image carrier that are to be printed, and
• wherein the control unit is further configured to, while printing is not being performed, change the image formation condition related to density while forming, on the image carrier, an image having a plurality of lines in a direction different from the movement direction of the surface of the image carrier, detect the image with the detection unit, and set a peak value of the output signal of the detection unit as a target value for the image formation condition.

An image forming apparatus comprising:

• an image carrier,
• an image forming unit configured to form, on the image carrier, a detection image that has one or more lines in a direction different from a movement direction of a surface of the image carrier;
• a light emitting unit configured to emit light toward the image carrier on which the detection image is formed;
• a light receiving unit configured to receive reflection light of the light emitted by the light emitting unit, and output a detection signal that corresponds to an amount of received reflection light including a specular reflection light component;
• a detection unit configured to output, as an output signal, a signal that corresponds to a difference between a detection signal value that corresponds to an amount of reflection light received from a first position at which the detection image is formed and a detection signal value that corresponds to an amount of reflection light received from a second position different from the first position;
• and
• a control unit configured to control an image formation condition related to density of an image to be formed, based on a peak value of the output signal of the detection unit,
• wherein the control unit forms the detection image using image data in which a width of the line in a movement direction of the surface of the image carrier is M dots (M being an integer) and a distance between lines is N dots (N being an integer), where M<N.

An image forming apparatus comprising:

• an image carrier,
• an image forming unit configured to form, on the image carrier, a detection image that has one or more lines in a direction different from a movement direction of a surface of the image carrier;
• a light emitting unit configured to emit light toward the image carrier on which the detection image is formed;
• a light receiving unit configured to receive reflection light of the light emitted by the light emitting unit, and output a detection signal that corresponds to an amount of received reflection light including a specular reflection light component;
• a detection unit configured to output, as an output signal, a signal that corresponds to a difference between a detection signal value that corresponds to an amount of reflection light received from a first position at which the detection image is formed and a detection signal value that corresponds to an amount of reflection light received from a second position different from the first position;
• and
• a control unit configured to control an image formation condition related to density of an image to be formed, based on the output signal of the detection unit.