Abstract: An effective image area can be properly corrected in accordance with the quantity of light from an irradiation unit by selecting, as the effective image area, pixels having light quantities more than or equal to a threshold value that allows accurate acquisition of a surface image of a recording medium, on the basis of a light quantity distribution of the light from the irradiation unit. This reduces the influence of mounting accuracy of the irradiation unit, and allows the recording medium to be identified accurately.

Abstract: The recording medium determination apparatus includes a transmission unit for transmitting an ultrasonic wave, a receiving unit for outputting a signal corresponding to the ultrasonic wave, a peak extraction unit for detecting a value of the signal output from the receiving unit, a control unit for determining basis weight of a recording medium based on the value of the signal, and a timer for measuring a period of time from when the transmission unit transmits the ultrasonic wave to the detection by the peak extraction unit. The control unit calculates, based on a period of time measured by the timer at the time of factory shipment and a period of time measured by the timer after the factory shipment, variation of a distance between the transmission unit and the receiving unit after the factory shipment.

Abstract: A recording material detecting apparatus includes a light guiding unit that allows first and second light to enter a surface of a recording material, respectively, in two directions which are not parallel; an imaging device that images a first light irradiated area and a second light irradiated area, on the surface of the recording material; and an output device that outputs information on a surface condition of the recording material based on an output of the imaging device. When viewed in a direction along the center optical axes of first and second light sources which are of the same type, the first and second light sources are arranged such that the respective reference lines of the rotational phases around the center optical axes are rotated in opposite directions by approximately the same angles from a line perpendicular to the direction where the first and second light sources are arrayed.

Abstract: A developing apparatus includes a developing unit configured to be detachable from and attachable to an image forming apparatus to contain a developer, a rotary member configured to rotate in the developing unit, and a detection unit installed on an internal surface of the developing unit and configured to detect a pressure caused by pressure through the developer by rotation of the rotary member. In addition, a measurement unit is configured to measure a period in which the pressure is changed, and a determination unit is configured to determine an amount of the developer in the developing unit based on the period detected by the measurement unit.

Abstract: A recording medium determination apparatus that determines grammage of a recording medium by using an ultrasonic wave includes a transmission unit configured to output an ultrasonic wave having a predetermined frequency, a reception unit configured to receive the ultrasonic wave output from the transmission unit and transmitted through the recording medium and output a received signal, a calculation unit configured to calculate a signal having a peak component according to a cycle of the received signal, and a determination unit configured to determine the grammage of the recording medium based on the signal calculated by the calculation unit.

Abstract: A recording material detection apparatus having a detecting device configured to detect a surface state of a recording material on the basis of reflected light from a surface of the recording material includes a reference surface to be irradiated with light from a light source, the detecting device includes a light-shielding portion configured to control conditions for detecting information relating to the surface state of the recording material on the basis of the reflected surface from the reference surface, and cover a portion of the reference panel other than the reference surface so as to prevent the light from the light source from being reflected from the portion of the reference panel other than the reference surface and being received by the light-receiving unit.

Abstract: A recording material detecting apparatus includes a light guiding unit that allows first and second light to enter a surface of a recording material, respectively, in two directions which are not parallel; an imaging device that images a first light irradiated area and a second light irradiated area, on the surface of the recording material; and an output device that outputs information on a surface condition of the recording material based on an output of the imaging device. When viewed in a direction along the center optical axes of first and second light sources which are of the same type, the first and second light sources are arranged such that the respective reference lines of the rotational phases around the center optical axes are rotated in opposite directions by approximately the same angles from a line perpendicular to the direction where the first and second light sources are arrayed.

Abstract: The image forming apparatus includes a developing unit that is detachable and contains a developer, a detection member that includes an electrode to be detected and is rotatable around a rotation axis in the developing unit, an agitator that moves around the rotation axis in the developing unit; an electrostatic capacitance sensor electrode provided on an exterior of the developing unit, an electrostatic capacitance sensor that detects electrostatic capacitance between the electrode to be detected and the electrostatic capacitance sensor electrode, and outputs data on the detected electrostatic capacitance, and a CPU that determines an amount of developer in the developing unit based on the data output from the electrostatic capacitance sensor.

Abstract: When a stirring member that stirs developer in a developer containing portion rotates at high speed, toner flies and the detection accuracy of light transmission type toner remaining amount detection is degraded. A developing apparatus including a developer containing portion that contains developer, a stirring member that stirs the developer in the developer containing portion, and a partition member which is disposed to separate the developer containing portion from a space adjacent to the developer containing portion and which bends to block at least a part of a light path, which is formed in the space and used to detect an amount of the developer, when being pressed by the stirring member via the developer.

Abstract: A grammage detection sensor according to an aspect of the present invention includes a transmission unit configured to transmit an ultrasonic wave, a reception unit configured to receive the ultrasonic wave transmitted from the transmission unit, and a control unit configured to detect a grammage of a recording material, when a plurality of recording materials are continuously conveyed between the transmission unit and the reception unit, on the basis of a first ultrasonic wave received by the reception unit after the ultrasonic wave is transmitted by the transmission unit between a preceding recording material and a recording material following the preceding recording material, and a second ultrasonic wave received via a recording material by the reception unit after the ultrasonic wave is transmitted by the transmission unit.

Abstract: A recording material determination device includes an ultrasonic wave transmission unit configured to transmit an ultrasonic wave to a recording material based on a driving signal, an ultrasonic wave receiving unit configured to receive the ultrasonic wave, a light exposure unit configured to expose the recording material to light, a light receiving unit configured to receive light, an amplification unit configured to amplify an ultrasonic wave received by the ultrasonic wave receiving unit to a first output value, and after the amplification unit amplifies the ultrasonic wave received by the ultrasonic wave receiving unit to the first output value, a control unit performs control so as to obtain the second output value by the light exposure unit and the light receiving unit during a period of time after the amplification of the ultrasonic wave is stopped and before the next ultrasonic wave comes to be transmittable.

Abstract: A sensor is attached to an apparatus having a fixing unit which fixes an image on a recording medium by heating the recording medium. The sensor includes: a transmission unit transmitting an ultrasonic wave to the recording medium; a reception unit receiving the ultrasonic wave via the recording medium, and output a signal corresponding to the received ultrasonic wave; and a detecting unit detecting information relating to a state of the recording medium which has changed by passing through the fixing unit, based on a first signal which the reception unit has output upon having received the ultrasonic wave before the recording medium has passed through the fixing unit, and a second signal which the reception unit has output upon having received the ultrasonic wave after the recording medium has passed through the fixing unit.

Abstract: A recording material determination apparatus includes a first detection unit configured to detect a characteristic corresponding to a surface condition of a recording material based on a captured image of a surface of the recording material, a second detection unit configured to detect a characteristic corresponding to a grammage of the recording material based on an ultrasonic wave detected via the recording material by irradiating the recording material with an ultrasonic wave, and a conveyance unit configured to convey the recording material. The first detection unit and the second detection unit are located opposite each other with respect to the conveyance unit.

Abstract: A recording material detection apparatus having a detecting device configured to detect a surface state of a recording material on the basis of reflected light from a surface of the recording material includes a reference surface to be irradiated with light from a light source, the detecting device includes a light-shielding portion configured to control conditions for detecting information relating to the surface state of the recording material on the basis of the reflected surface from the reference surface, and cover a portion of the reference panel other than the reference surface so as to prevent the light from the light source from being reflected from the portion of the reference panel other than the reference surface and being received by the light-receiving unit.

Abstract: A recording material determination apparatus includes a transmission unit configured to transmit an ultrasonic wave, a reception unit configured to receive an ultrasonic wave transmitted from the transmission unit and then via a recording material, and a control unit configured to cause the transmission unit to transmit an ultrasonic wave a plurality of times under different conditions, measure an output value a plurality of times, and determine the recording material based on the output values measured a plurality of times.

Abstract: A grammage detection sensor which detects a grammage of a recording medium using an ultrasonic wave includes a transmitting unit configured to transmit the ultrasonic wave and a receiving unit including a first vibration member configured to receive the ultrasonic wave that is transmitted from the transmitting unit and passes through the recording medium. The receiving unit includes a guide member configured to guide the ultrasonic wave that passes through the recording medium to the first vibration member. A length from a surface of the first vibration member to a plane including an end plane of the guide member along a line that passes through a center of the first vibration member and is perpendicular to the first vibration member is approximately n times of one-half wavelength of the ultrasonic wave transmitted from the transmitting unit where n is an integer of one or greater.

Abstract: A recording material detection apparatus having a detecting device configured to detect a surface state of a recording material on the basis of reflected light from a surface of the recording material includes a reference surface to be irradiated with light from a light source, the detecting device includes a light-shielding portion configured to control conditions for detecting information relating to the surface state of the recording material on the basis of the reflected surface from the reference surface, and cover a portion of the reference panel other than the reference surface so as to prevent the light from the light source from being reflected from the portion of the reference panel other than the reference surface and being received by the light-receiving unit.

Abstract: An image forming apparatus includes a rotatable member which is provided on and rotatable about a rotation shaft in a detachably mountable developing unit containing a developer and has flexibility so that it is flexed depending on a resistance of the developer; an electroconductive member to be detected which is provided on the rotatable member; a detecting electrode provided in a neighborhood of an outer wall surface of a bottom of the developing unit; a converting portion for detecting an electrostatic capacity between the member to be detected and the detecting electrode and for converting the electrostatic capacity into an electric signal; a measuring portion for measuring a time duration in which the electric signal converted by the converting portion exceeds a predetermined threshold; and a discriminating portion for discriminating an amount of the developer on the basis of the time duration measured by the measuring portion.

Abstract: There is provided a recording medium imaging device capable of properly selecting pixels used for determining the kind of the recording medium from the captured surface image to remove pixels from which the surface property of the recording medium cannot be properly determined because the pixels extremely high in light quantity are affected by some sort of dirt or scratches in determining the kind of a recording medium. This allows the determination of kind of the recording medium based on the normally captured surface image to reduce the decrease in accuracy in determining the kind of the recording medium.

Abstract: A protection member is arranged such that the distance from an opening plane of a reception guide to the center of the protection member is half of the distance from the opening plane of the reception guide to the surface of a reception vibration member. In other words, the arrangement position of the protection member is in the center between the opening plane of the reception guide and the surface of the reception vibration member. Accordingly, even if a protection member is arranged, a transmission coefficient is obtained that is equal to a transmission coefficient in the case where no protection member is present.