Information processing apparatus and image forming apparatus with identification of reflective surface of rotating polygonal mirror

Patent metadata

Field	Value
Publication number	US-10831124-B2
Application number	US-201916563111-A
Country	US
Kind code	B2
Filing date	Sep 6, 2019
Priority date	Sep 26, 2018
Publication date	Nov 10, 2020
Grant date	Nov 10, 2020

Abstract

An apparatus identifies reflective surfaces used for scanning a first photosensitive member and a second photosensitive member. A first storage stores correction data corresponding to each of reflective surfaces of a first rotating polygonal mirror. A first correction unit corrects, on a basis of the correction data and information indicating the reflective surface, image data in association with the reflective surface. A second storage stores correction data corresponding to each of reflective surfaces of a second rotating polygonal mirror. A second correction unit corrects, on a basis of the correction data and information indicating the reflective surface, image data in association with the reflective surface.

First claim

What is claimed is:

1. An information processing apparatus connectable to an image forming apparatus comprising an image forming unit,
wherein the image forming unit comprises:
a first photosensitive member configured to carry a toner image of a first color;
a first transfer unit configured to transfer the toner image of the first color formed on the first photosensitive member to an intermediate transfer member;
a first light source configured to output light on a basis of image data of the first color;
a first rotating polygonal mirror including a plurality of reflective surfaces and configured to scan the first photosensitive member by rotating to deflect the light output from the first light source by the plurality of reflective surfaces;
a first light receiving unit configured to receive the light deflected by the first rotating polygonal mirror;
a first output unit configured to output a first signal in response to reception of the light by the first light receiving unit, the first signal having a first level and a second level;
a second photosensitive member provided downstream of the first photosensitive member in a rotational direction in which the intermediate transfer member rotates, and configured to carry a toner image of a second color;
a second light source configured to output light on a basis of image data of the second color;
a second rotating polygonal mirror including a plurality of reflective surfaces and configured to scan the second photosensitive member by rotating to deflect the light output from the second light source by the plurality of reflective surfaces;
a second light receiving unit configured to receive the light deflected by the second rotating polygonal mirror; and
a second output unit configured to output a second signal in response to reception of the light by the second light receiving unit, the second signal having the first level and the second level;

wherein the information processing apparatus comprises:
an identifying unit configured to identify a reflective surface used for scanning the first photosensitive member from among the plurality of reflective surfaces of the first rotating polygonal mirror on a basis of the first signal, and to identify a reflective surface used for scanning the second photosensitive member from among the plurality of reflective surfaces of the second rotating polygonal mirror on a basis of the second signal, wherein the identifying unit identifies the reflective surface used for scanning the second photosensitive member after identifying the reflective surface used for scanning the first photosensitive member;
a first storage unit configured to store a plurality of pieces of correction data each of which corresponds to a different one of the plurality of reflective surfaces of the first rotating polygonal mirror;
a first correction unit configured to correct, on a basis of the correction data stored in the first storage unit and information indicating the reflective surface identified by the identifying unit, image data of the first color in association with the reflective surface to adjust a position of the toner image on the first photosensitive member;
a third output unit configured to output the image data corrected by the first correction unit to the image forming unit;
a second storage unit configured to store a plurality of pieces of correction data each of which corresponds to a different one of the plurality of reflective surfaces of the second rotating polygonal mirror;
a second correction unit configured to correct, on a basis of the correction data stored in the second storage unit and information indicating the reflective surface identified by the identifying unit, image data of the second color in association with the reflective surface to adjust a position of the toner image on the second photosensitive member; and
a fourth output unit configured to output the image data corrected by the second correction unit to the image forming unit.

2. The information processing apparatus according to claim 1 , wherein the first photosensitive member is provided such that the first photosensitive member is adjacent to the second photosensitive member.

3. The information processing apparatus according to claim 1 , wherein the first color is yellow and the second color is magenta.

4. The information processing apparatus according to claim 1 , wherein the identifying unit is configured to
identify the reflective surface used for scanning the first photosensitive member from among the plurality of reflective surfaces of the first rotating polygonal mirror on the basis of the first signal by selecting the first signal from the first signal and the second signal, and
identify the reflective surface used for scanning the second photosensitive member from among the plurality of reflective surfaces of the second rotating polygonal mirror on the basis of the second signal by selecting the second signal from the first signal and the second signal.

5. The information processing apparatus according to claim 1 , further comprising:
a third storage unit configured to store information relating to a time interval between a first timing when the first signal changes from the first level to the second level and a second timing when the first signal changes from the first level to the second level, the second timing being a next timing of the first timing, and the information being preliminarily acquired; and
a measuring unit configured to measure the time interval in the first signal;
wherein the identifying unit is configured to identify the reflective surface used for scanning the first photosensitive member on a basis of the time interval in the first signal measured by the measuring unit and the information stored in the third storage unit.

6. The information processing apparatus according to claim 1 , further comprising a first detection unit configured to detect a change of the first signal from the first level to the second level,
wherein the identifying unit updates a first surface information indicating the reflective surface used for scanning the first photosensitive member each time the change is detected by the first detection unit; and
wherein the first correction unit corrects the image data corresponding to the image to be formed on the first photosensitive member on a basis of the first surface information.

7. The information processing apparatus according to claim 1 ,
wherein a circuit board on which the identifying unit is provided is a circuit board different from a circuit board on which the first output unit and the second output unit are provided; and
wherein the circuit board on which the identifying unit is provided is connected, by a cable, to the circuit board on which the first output unit and the second output unit are provided.

8. The information processing apparatus according to claim 5 ,
wherein the third storage unit is configured to store information relating to a time interval between a first timing when the second signal changes from the first level to the second level and a second timing when the second signal changes from the first level to the second level, the second timing being a next timing of the first timing, and, the information being preliminarily acquired;
wherein the measuring unit measures the time interval in the second signal;
wherein the identifying unit is configured to identify the reflective surface used for scanning the second photosensitive member on a basis of the time interval in the second signal measured by the measuring unit and the information stored in the third storage unit.

9. The information processing apparatus according to claim 6 , further comprising a second detection unit c

Assignees

• Canon Kk

Inventors

• Ozawa Manabu

Classifications

• G03G15/011

  for exposing · CPC title

• G03G15/043 Primary

  with means for controlling illumination or exposure (G03G15/041 takes precedence) · CPC title