Abstract: An image forming apparatus that generates a synchronization signal without breaking laser diodes (LDs). The LDs output beams, which in turn are deflected to scan a photosensitive member. The synchronization signal is generated upon detecting the deflected beams. The LDs output the beams so as to generate the synchronization signal, based on which the output timing of the beams from the LDs is controlled. It is possible to select a first mode in which at least two of the LDs output the beams so as to generate the synchronization signal, and a second mode in which one of the LDs output the beams so as to generate the synchronization signal. The value of drive current supplied to at least two of the LDs when the first mode is selected is smaller than the value of drive current supplied to one of the LDs when the second mode is selected.

Abstract: First and second light amount detection elements are arranged on a scanning line of a laser beam. The first light amount detection element receives a laser beam having a first light amount, and the second light amount detection element receives a laser beam having a second light amount that is lower than the first light amount. The detection signal that is output by the second light amount detection element is amplified by an amplifier and used as a synchronization signal. Here, an amplification factor of this amplifier is greater than an amplification factor of another amplifier for amplifying the detection signal that is output by the first light amount detection element. The detection signals amplified by the amplifiers are modified by a modification coefficient that correspond to the amplification factors, and used as signals that indicate the light amounts.

Abstract: An image forming apparatus capable of ensuring a sufficient difference between amounts of light reflected from a base such as a transfer material and from a toner pattern in the detection of the toner pattern for registration correction control by a reflective optical sensor. The image forming apparatus includes a pattern generator for generating a toner pattern, a pattern detection sensor for detecting the toner pattern formed on the intermediate transfer belt, a pattern density decider for determining the density of the toner pattern that makes the amount of light received by the sensor in detection of the toner pattern equal to or less than a predetermined value.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.

Abstract: A light scanning device that performs rapid scanning synchronization timing detection to thereby enable automatic light amount control to be executed rapidly and with high accuracy. A light amount sensor disposed on a scanning line of the laser light receives the laser light. A controller controls the timing of emission by the laser emitting device and a light amount of the laser light based on image data, according to an output from the light amount sensor. A temperature sensor detects the temperature of the laser emitting device or in the light scanning device. A storage section stores data indicative of a relationship between temperature, current supplied to the laser emitting device, and light amount.

Abstract: An image forming apparatus that generates a synchronization signal without breaking laser diodes (LDs). The LDs output beams, which in turn are deflected to scan a photosensitive member. The synchronization signal is generated upon detecting the deflected beams. The LDs output the beams so as to generate the synchronization signal, based on which the output timing of the beams from the LDs is controlled. It is possible to select a first mode in which at least two of the LDs output the beams so as to generate the synchronization signal, and a second mode in which one of the LDs output the beams so as to generate the synchronization signal. The value of drive current supplied to at least two of the LDs when the first mode is selected is smaller than the value of drive current supplied to one of the LDs when the second mode is selected.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.

Abstract: An image forming apparatus includes a pattern forming unit which forms a light amount adjustment pattern on an image carrier belt, a light amount control unit which controls the amount of light irradiating the image carrier belt and pattern, a detection sensor which detects reflected light amounts from the image carrier belt and pattern with respect to the irradiating light amount and stores the detection results in a storage unit, a calculation unit which calculates the correspondence between the irradiating light amount and the reflected light amounts from the image carrier belt and pattern on the basis of the detection results and stores the calculation results in the storage unit, and a light amount decision unit which decides, on the basis of the calculation results, a light amount at which the difference between the reflected light amounts from the image carrier belt and pattern exhibits a value set in advance.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.

Abstract: An image forming apparatus includes a pattern forming unit which forms a light amount adjustment pattern on an image carrier belt, a light amount control unit which controls the amount of light irradiating the image carrier belt and pattern, a detection sensor which detects reflected light amounts from the image carrier belt and pattern with respect to the irradiating light amount and stores the detection results in a storage unit, a calculation unit which calculates the correspondence between the irradiating light amount and the reflected light amounts from the image carrier belt and pattern on the basis of the detection results and stores the calculation results in the storage unit, and a light amount decision unit which decides, on the basis of the calculation results, a light amount at which the difference between the reflected light amounts from the image carrier belt and pattern exhibits a value set in advance.

Abstract: With an electrophotographic image forming apparatus which forms an image by using a plurality of light emitting elements, since a photodiode (PD) is disposed in the vicinity of the plurality of light emitting elements and, therefore, the PD also receives a laser beam emitted only by a bias current during the APC period, setting a bias current based on a result of light amount detection by the PD does not result in a bias current setting with sufficient accuracy. To solve this issue, an electrophotographic image forming apparatus forms an electrostatic latent image pattern on a photosensitive drum, and controls the value of the bias current set for a first light emitting element based on the potential of the electrostatic latent image pattern detected by a potential sensor so that the value of the bias current for the first light emitting element comes close to a minimum value of the drive current supplied to the first light emitting element to form the electrostatic latent image.

Abstract: An image forming apparatus includes a pattern forming unit which forms a light amount adjustment pattern on an image carrier belt, a light amount control unit which controls the amount of light irradiating the image carrier belt and pattern, a detection sensor which detects reflected light amounts from the image carrier belt and pattern with respect to the irradiating light amount and stores the detection results in a storage unit, a calculation unit which calculates the correspondence between the irradiating light amount and the reflected light amounts from the image carrier belt and pattern on the basis of the detection results and stores the calculation results in the storage unit, and a light amount decision unit which decides, on the basis of the calculation results, a light amount at which the difference between the reflected light amounts from the image carrier belt and pattern exhibits a value set in advance.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.

Abstract: A color image forming apparatus which is capable of performing color misregistration correction, and registration of images and a recording sheet while reducing the toner consumption amount. An image forming section is caused to form a first reference image having a first density for adjusting a density of an adjusting image, and a second reference image having a second density different from the first density. A sensor detects the first reference image and the second reference image. The first density is determined as a density of the adjusting image, if an output signal level of the sensor at a time of detection of the first reference image is not lower than a predetermined value, and the output signal level of the sensor at a time of detection of the second reference image is lower than the predetermined value.

Abstract: An image forming apparatus includes a pattern forming unit which forms a light amount adjustment pattern on an image carrier belt, a light amount control unit which controls the amount of light irradiating the image carrier belt and pattern, a detection sensor which detects reflected light amounts from the image carrier belt and pattern with respect to the irradiating light amount and stores the detection results in a storage unit, a calculation unit which calculates the correspondence between the irradiating light amount and the reflected light amounts from the image carrier belt and pattern on the basis of the detection results and stores the calculation results in the storage unit, and a light amount decision unit which decides, on the basis of the calculation results, a light amount at which the difference between the reflected light amounts from the image carrier belt and pattern exhibits a value set in advance.

Abstract: An image forming apparatus includes a pattern forming unit which forms a light amount adjustment pattern on an image carrier belt, a light amount control unit which controls the amount of light irradiating the image carrier belt and pattern, a detection sensor which detects reflected light amounts from the image carrier belt and pattern with respect to the irradiating light amount and stores the detection results in a storage unit, a calculation unit which calculates the correspondence between the irradiating light amount and the reflected light amounts from the image carrier belt and pattern on the basis of the detection results and stores the calculation results in the storage unit, and a light amount decision unit which decides, on the basis of the calculation results, a light amount at which the difference between the reflected light amounts from the image carrier belt and pattern exhibits a value set in advance.

Abstract: An image forming apparatus has a function for adjusting the position at which a toner image is formed on a printing material, based upon amount of light reflected from a toner image that has been formed on an image carrier. The light-emitting unit emits light that irradiates the image carrier, and the detecting unit detects an amount of substrate-light reflected from the substrate of the image carrier. The determining unit determines whether the difference between the amount of substrate-light detected at a first point in time and the amount of substrate-light detected at a second point in time later than the first point in time is greater than a predetermined threshold value. The light-power control unit increases the amount of light in the light-emitting unit if the difference is greater than the predetermined threshold value.