According to one embodiment, there is provided a toner cartridge used in an image forming apparatus including a processor which forms a toner pattern image on a photoconductive member, transfers the toner pattern image on a medium, and changes an image forming condition based on a detection result obtained by optically detecting the toner pattern transferred onto the medium, the toner cartridge including: a toner accommodating container accommodating a toner, and a memory. The memory stores a plurality of reference data which are determined according to toner characteristics in the toner accommodating container and a value indicating an image forming execution amount, and are used for applying reference values for an optical detection result of a toner pattern formed by the toner on the medium.

According to one embodiment, there is provided a toner cartridge used in an image forming apparatus including a processor which forms a toner pattern image on a photoconductive member, transfers the toner pattern image on a medium, and changes an image forming condition based on a detection result obtained by optically detecting the toner pattern image transferred onto the medium, the toner cartridge including: a toner accommodating container accommodating a toner, and a memory. The memory stores reference data which is determined according to toner characteristics in the toner accommodating container, and is used for applying a reference value for an optical detection result of a toner pattern formed by the toner on the medium.

An image forming apparatus, including: a photoconductor; a developing device; a developer storage; a supplier configured to supply developer; an optical sensor; and a controller configured to execute: a developing process of developing an electrostatic latent image on the photoconductor; a usage-amount obtaining process of obtaining a usage amount of the developer; a supplying process of supplying the developer to the developing device every time when the obtained usage amount becomes equal to or greater than a first threshold; and a detecting process of detecting, by the optical sensor, an amount of the developer in the developing device every time when the obtained usage amount becomes equal to or greater than a second threshold larger than the first threshold, and wherein the controller is configured to execute the detecting process in a period different from a period in which the developing process is being executed.

According to one embodiment, there is provided a toner cartridge used in an image forming apparatus including a processor which forms a toner pattern image on a photoconductive member, transfers the toner pattern image on a medium, and changes an image forming condition based on a detection result obtained by optically detecting the toner pattern transferred onto the medium, the toner cartridge including: a toner accommodating container accommodating a toner, and a memory. The memory stores a plurality of reference data which are determined according to toner characteristics in the toner accommodating container and a value indicating an image forming execution amount, and are used for applying reference values for an optical detection result of a toner pattern formed by the toner on the medium.

A system and method for determining print cartridge authenticity in a printer includes an electrostatic process unit with a photoconductive drum configured to selectively generate a toner pattern from an associated toner cartridge based at least in part on electronic data associated with the toner cartridge. A transfer belt receives the toner pattern from the photoconductive drum and a sensor sensing the toner pattern on the transfer belt. A processor compares the toner pattern with a sensed toner pattern and generates an error condition when the toner pattern does not substantially match the sensed toner pattern. The toner includes an infrared reflective additive or an ultraviolet fluorescing additive and the sensor is configured to sense in the infrared or ultraviolet frequencies. The processor is configured to generate an error condition when the additive is not sensed by the sensor.

A developing cartridge includes a casing, a developer-carrying member, a supply member, a developing electrode, a supply electrode, and an insulating member. The casing is configured to accommodate therein developer. The developer-carrying member is configured to rotate about a rotational axis and carry the developer thereon. The supply member is configured to supply the developer to the developer-carrying member. The developing electrode is configured to be electrically connected to the developer-carrying member. The supply electrode is configured to be electrically connected to the supply member. The insulating member insulates the developing electrode and the supply electrode with each other. The developing electrode, the insulating member, and the supply electrode are overlapped in this order in an axial direction of the rotational axis.

A developing cartridge includes a casing, a developer-carrying member, a supply member, a developing electrode, a supply electrode, and an insulating member. The casing is configured to accommodate therein developer. The developer-carrying member is configured to rotate about a rotational axis and carry the developer thereon. The supply member is configured to supply the developer to the developer-carrying member. The developing electrode is configured to be electrically connected to the developer-carrying member. The supply electrode is configured to be electrically connected to the supply member. The insulating member insulates the developing electrode and the supply electrode with each other. The developing electrode, the insulating member, and the supply electrode are overlapped in this order in an axial direction of the rotational axis.

A color imaging device includes a plurality of developer rolls with a common operating point, such as a common operating voltage. To determine the operating point, an acceptable range of color density is determined for each toner, the range being lighter and darker than an optimum color density for that toner. A search range is devised such that values within the range are examined relative to deviations from the optimum color density per each toner. The common operating point is selected as that having the lowest deviation per all toners. Also, if the common operating point corresponds to a color density darker than the acceptable range of color density for any toner, additional halftoning occurs compared to traditional halftoning, such as for continuous tones or solids. In this way, four color developer rolls can be operated from a single power supply, yet still provide acceptable color images.

An image forming apparatus includes an image bearing member, a developing unit to develop an electrostatic latent image formed on the image bearing member with toner, and a detachable toner container in which toner for supplying to the developing unit is contained. A measuring unit measures information relating to an amount of toner in the developing unit, and a determination unit determines an amount of toner in the developing unit based on the measured information. In a case where the determination unit determines that the toner container is empty, a supply operation for supplying toner from the toner container to the developing unit is performed and the measuring unit measures the information relating to an amount of toner in the toner container after the supply operation is performed, and in a case where the information relating to an amount of toner in the toner container measured after the supply operation is performed is within a measurement error range, the determination unit determines that the toner container is empty.

A color imaging device includes a plurality of developer rolls with a common operating point, such as a common operating voltage. To determine the operating point, an acceptable range of color density is determined for each toner, the range being lighter and darker than an optimum color density for that toner. A search range is devised such that values within the range are examined relative to deviations from the optimum color density per each toner. The common operating point is selected as that having the lowest deviation per all toners. Also, if the common operating point corresponds to a color density darker than the acceptable range of color density for any toner, additional halftoning occurs compared to traditional halftoning, such as for continuous tones or solids. In this way, four color developer rolls can be operated from a single power supply, yet still provide acceptable color images.