Abstract: A developing device includes a developer carrying member configured to carry a developer, containing toner and a carrier, for developing an electrostatic latent image formed on an image bearing member, a developer container configured to accommodate the developer, and an oscillation circuit including a resonance circuit including a coil and a circuit portion containing a capacitor and configured to oscillate a signal for detecting a toner concentration of the developer accommodated in the developer container. The coil is formed integrally with the developer container by a metal film, and the coil is disposed on an inner wall surface of the developer container.

Abstract: A master slave communication system capable of reducing a manufacturing cost is provided. The mater slave communication system includes a master node and a plurality of slave nodes having the same initial address. A communication between the master node and one slave node among the plurality of slave nodes is established by using the initial address set as an address of the one slave node. The address of the one slave node is changed into another address which has been transmitted from the master node to the one slave node through the established communication and is different from the initial address.

Abstract: An image forming apparatus includes: an image forming unit configured to form an image on an image bearing member based on an image forming condition, an optical sensor including: a light emitter configured to irradiate the image bearing member with light based on a supplied current; and a light receiver configured to receive reflected light of the light emitted from the light emitter; a temperature detector configured to detect a temperature of the optical sensor; and a controller configured to: control the image forming unit to form a detection image on the image bearing member; control the optical sensor to detect reflected light from the detection image; and adjust the image forming condition based on a result of detecting the detection image by the optical sensor. The controller is configured to control the light emitter to emit light; and generate a correction condition.

Abstract: A developing device includes a developer carrying member for carrying a developer, containing toner and a carrier, for developing an electrostatic latent image formed on an image bearing member; a developer container for accommodating the developer; and an oscillation circuit including a resonance circuit constituted by a coil and a circuit portion containing a capacitor and for oscillating a signal for detecting a toner concentration of the developer accommodated in the developer container. The coil is formed on an inner wall surface of the developer container.

Abstract: An image forming apparatus includes: an image. forming unit configured to form an image on an image bearing member based on an image forming condition, an optical sensor including: a light emitter configured to irradiate the image bearing member with light based on a supplied current; and a light receiver configured to receive reflected light of the light emitted from the light emitter; a temperature detector configured to detect a temperature of the optical sensor; and a controller configured to: control the image forming unit to form a detection image on the image bearing member; control the optical sensor to detect reflected light from the detection image; and adjust the image forming condition based on a result of detecting the detection image by the optical sensor. The controller is configured to control the light emitter to emit light; and generate a correction condition.

Abstract: A master slave communication system capable of reducing a manufacturing cost is provided. The mater slave communication system includes a master node and a plurality of slave nodes having the same initial address. A communication between the master node and one slave node among the plurality of slave nodes is established by using the initial address set as an address of the one slave node. The address of the one slave node is changed into another address which has been transmitted from the master node to the one slave node through the established communication and is different from the initial address.

Abstract: An image forming apparatus includes an optical sensor for detecting an image formed on an intermediate transfer belt. The optical sensor includes first and second light emitting diodes (LEDs) and first and second photodiodes (PDs). The first and second LEDs irradiate an optical-axis center point of an intermediate transfer belt. The first PD is arranged at a position at which an optical axis of specularly reflected light of light emitted from the second LED and an optical axis along which specularly reflected light of light emitted from the first LED is received form a first angle. The second PD is arranged at a position at which the optical axis of the specularly reflected light of the light emitted from the second LED and an optical axis along which diffused reflected light of the light emitted from the second LED is received form a second angle different from the first angle.

Abstract: An image forming apparatus includes an optical sensor configured to detect an image formed on an intermediate transfer belt. The optical sensor includes a first LED, a second LED, a first PD, and a second PD. The first LED and the second LED irradiate an optical-axis center point of an intermediate transfer belt. The first PD is arranged at a position at which an optical axis of specularly reflected light of light emitted from the second LED and an optical axis along which specularly reflected light of light emitted from the first LED is received form an angle ?. The second PD is arranged at a position at which the optical axis of the specularly reflected light of the light emitted from the second LED and an optical axis along which diffused reflected light of the light emitted from the second LED is received.

Abstract: An image forming apparatus includes a plurality of image forming units configured to form images of different colors on a transfer member, a comparator configured to compare values of color patterns measured by a sensor with a threshold, and a controller configured to determine whether the threshold corresponds to a target threshold for a current color pattern among the color patterns while the color patterns are measured by the sensor, detect color misregistration concerning the color patterns based on a comparison result of the comparator, and control relative positions of images of the different colors to be formed by the plurality of image forming units, based on the color misregistration.

Abstract: An image forming apparatus including a plurality of image forming units configured to form images of different colors on a transfer member, a comparator configured to compare values of the color patterns measured by a sensor with a threshold, and a controller configured to determine whether the threshold corresponds to a target threshold for a current color pattern among the color patterns while the color patterns are measured by the sensor, detect color misregistration concerning the color patterns based on a comparison result of the comparator, and control relative positions of images of the different colors to be formed by the plurality of image forming units, based on the color misregistration.

Abstract: An image forming apparatus includes a plurality of image forming units, an intermediate transfer member, a detection unit, and a controller. The controller is configured to control the plurality of image forming units to form, on the intermediate transfer member, a pattern image including a first detection image having a reference color among the plurality of detection images and a second detection image having another color among the plurality of detection images. The first detection image and the second detection image are superimposed on a predetermined detection image. The controller is configured to control the detection unit to detect the amount of color misregistration which is related to a relative position of the first detection image and the second detection image, and to determine an adjustment value for adjusting an image write start timing of the other color different from the reference color.

Abstract: An image forming apparatus comprises a plurality of image forming units, an intermediate transfer member, a detection unit, and a controller. The controller is configured to control the plurality of image forming units to form, on the intermediate transfer member, a pattern image including a first detection image having a reference color among the plurality of detection images and a second detection image having another color among the plurality of detection images. The first detection image and the second detection image are superimposed on a predetermined detection image. The controller is configured to control the detection unit to detect the amount of color misregistration which is related to a relative position of the first detection image and the second detection image, and to determine an adjustment value for adjusting an image write start timing of the other color different from the reference color.

Abstract: An image forming apparatus includes a plurality of white reference plates, a plurality of measurement units configured to be arranged in positions opposed to the respective plurality of white reference plates, irradiate the white reference plates with light, and measure reflected light from the white reference plates, and a determination unit configured to determine an abnormality of the plurality of white reference plates by using respective measurement results measured by the plurality of measurement units.

Abstract: A threshold for detecting a position of a lateral edge of a sheet is more accurately determined, whereby the accuracy of detection of the lateral edge position of the sheet is improved. A line sensor includes a plurality of element blocks. Each element block includes a plurality of pixels. The threshold for detecting the lateral edge position is determined based on a light level and a dark level of signals output from an element block that is actually used to detect the lateral edge position of the sheet.

Abstract: A color image forming apparatus configured to form a combination toner pattern including a second toner image formed downstream in a conveying direction of an intermediate transfer belt on a first toner image and a third toner image formed upstream in the conveying direction of the intermediate transfer belt on the first toner image so that the second and the third toner images cover at least a portion of the first toner image.

Abstract: An image forming apparatus includes a plurality of white reference plates, a plurality of measurement units configured to be arranged in positions opposed to the respective plurality of white reference plates, irradiate the white reference plates with light, and measure reflected light from the white reference plates, and a determination unit configured to determine an abnormality of the plurality of white reference plates by using respective measurement results measured by the plurality of measurement units.

Abstract: A threshold for detecting a position of a lateral edge of a sheet is more accurately determined, whereby the accuracy of detection of the lateral edge position of the sheet is improved. A line sensor includes a plurality of element blocks. Each element block includes a plurality of pixels. The threshold for detecting the lateral edge position is determined based on a light level and a dark level of signals output from an element block that is actually used to detect the lateral edge position of the sheet.

Abstract: A low density area is caused at a trailing edge of an image formed on a photosensitive drum. This low density area is less likely to be caused when the density of the image is higher and the humidity is lower. To prevent generation of such low density area, if a color misregistration detection toner pattern having a high density is formed, in a low humidity environment, an excessively large amount of toner is consumed unnecessarily. In response, the density of the color misregistration detection toner pattern is adjusted based on the humidity.

Abstract: A color image forming apparatus configured to form a combination toner pattern including a second toner image formed downstream in a conveying direction of an intermediate transfer belt on a first toner image and a third toner image formed upstream in the conveying direction of the intermediate transfer belt on the first toner image so that the second and the third toner images cover at least a portion of the first toner image.