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 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: Disclosed herein is an image forming apparatus capable of avoiding positional interference between an electrical potential sensor and a developing device during the installation or separation of the developing device. The positional interference is prevented by moving the electrical potential sensor out of the movement path of the developing device in association with the opening/closing movement a cover for an access opening in the body of the image forming apparatus for the installation/separation of the developing device. A link device connects the cover and the electrical potential sensor to each other so as to cause the movement of the electrical potential sensor in linkage with the opening/closing of the cover. The link device serves as an anti-interference device that prevents the positional interference between the developing device and the electrical potential sensor.

Abstract: A potential sensor for detecting a surface potential of an electrophotographic photosensitive member includes an insulative film; a thin film electrode layer formed on the film; a curved portion formed by folding back the film so that the thin film electrode layer is inwardly located, the curved potion functioning as a detecting portion for detecting the surface potential of the electrophotographic photosensitive member in contact with the electrophotographic photosensitive member; and an electroconductive shielding portion provided so as to cover an outer surface of the film except for at least an area in which the curved portion is contactable to the electrophotographic photosensitive member, the shielding portion being electrically grounded.

Abstract: There is provided an image forming apparatus and method capable of reducing a measurement error in a measurement result of the surface potential of an electrostatic latent image formed on the surface of an image bearing member. The measurement error occurs under the influence of an electric field generated from a pre-exposed area. Consequently, miniaturization of an image forming apparatus and consistent print quality can be achieved. The image forming apparatus includes an image forming control section for determining an error correction value corresponding to the charge state of a latent image on the basis of relationships between charge states of the latent image and error correction values which have been prepared in advance, computing an error corrected potential measurement value using the error correction value and a potential measurement value, and controlling the image forming apparatus on the basis of the error corrected potential measurement value.

Abstract: In an embodiment of the invention, a metal shield case and a metal shutter are electrically conducted to each other by using a contact part and are made to have the same potential. By this, the shutter does not electrically exert a bad influence on detection accuracy of a surface potential sensor, the closing performance of the shutter is improved, and the miniaturization or reduction in cost of the surface potential sensor can be realized.

Abstract: This is a system to improve final xerographic image by providing uniformity in both pre-imaged and imaged photoconductive drums or belts. An ESV is placed after the exposure imaging station so that it can measure the voltage on the photoreceptor (PR) belt or drum obtaining a periodic photoreceptor signature. This signature is communicated to a controller and stored therein. After both pre-imaged and imaged signatures are obtained, the controller compensates for these signatures to all imaging runs thereafter to ensure uniform voltage and thereby uniform final images.

Abstract: A potential sensor for detecting a surface potential of an electrophotographic photosensitive member includes an insulative film; a thin film electrode layer formed on the film; a curved portion formed by folding back the film so that the thin film electrode layer is inwardly located, the curved potion functioning as a detecting portion for detecting the surface potential of the electrophotographic photosensitive member in contact with the electrophotographic photosensitive member; and an electroconductive shielding portion provided so as to cover an outer surface of the film except for at least an area in which the curved portion is contactable to the electrophotographic photosensitive member, the shielding portion being electrically grounded.

Abstract: A potential sensor is provided in which the adhesion of toner particles to the potential sensor is reduced or prevented from occurring, reducing or preventing the occurrence of a situation that accurate detection cannot be performed. The potential sensor has a movable member, detecting electrodes formed on the movable member, a support which movably supports the movable member, a driving mechanism which drives the movable member, and a stationary member which supports the support. Between the movable member and the stationary member, a first gap is so formed as to make the movable member 101 movable. The first gap has a part that is not larger in width than the maximum size of toner particles when the movable member is not elastically deformed and is at a neutral position.

Abstract: In an embodiment of the invention, a metal shield case and a metal shutter are electrically conducted to each other by using a contact part and are made to have the same potential. By this, the shutter does not electrically exert a bad influence on detection accuracy of a surface potential sensor, the closing performance of the shutter is improved, and the miniaturization or reduction in cost of the surface potential sensor can be realized.

Abstract: The electric potential measuring instrument comprises an electrode arranged on a semiconductor substrate at a position opposite to the object of measurement and a modulator for modulating the coupling capacitance between the object of measurement and the electrode. The electrode is the gate electrode of a field effect type transistor. The modulated electric current that flows between the source diffusion region and the drain diffusion region of the field effect type transistor is synchronously detected by a detection circuit with the modulation frequency of the modulator. The output signal that appears on the gate electrode of a field effect transistor can be measured with ease by changing the coupling capacitance between the electrode of an electric potential measuring instrument and an object of measurement.

Abstract: A method for measuring an amount of toner on a recording medium that can accurately measure the toner amount. Information on the recording medium to which the toner is fixed is acquired. The toner fixed to the recording medium is irradiated with laser light. A light intensity distribution of reflected light of the laser light is detected. The amount of the toner on the recording medium is calculated on the basis of the acquired recording medium information and the detected light intensity distribution.

Abstract: To provide an electric potential measuring device which is useful in realizing size reduction, high sensitivity, and high reliability. The electric potential measuring device includes: an oscillating device which includes torsion springs, and an oscillating body axially supported by the springs to oscillate; and signal detecting unit which is located on a surface of the oscillating body. A capacitance between the detection electrode and a surface of an electric potential measuring object is varied by varying a distance therebetween by the oscillating device, whereby an output signal appearing on the detection electrode is detected.

Abstract: A method for determining a location of an uncharged region on a photoconductive drum in an electrophotographic device, comprising rotating the photoconductive drum, and charging a surface of the drum via a charge roller by application of a voltage to the charge roller. An electrical characteristic of one of the charge roller or photoconductive drum is measured, and an alteration in the electrical characteristic is used to determine a location of the uncharged region.

Abstract: A surface potential distribution measurement method and device including setting a sample having a surface with a surface potential distribution in a sample installation unit wherein both an electric field intensity formed on the sample surface and a potential bias component of the sample are variable, and scanning the sample surface in a one-dimensional or two-dimensional manner by irradiating a charged particle beam to the sample. The method also includes obtaining a detection signal from charged particles generated by the scanning, to measure the surface potential distribution of the sample by varying the electric field intensity and the potential bias component in order to control a quantity of the detection signal obtained from the charged particles.

Abstract: In a xerographic printing apparatus, feedback on surface charge at a plurality of locations across a length of a photoreceptor may be desirable to assess charge uniformity, for example, to ensure color consistency across multiple marking engines in tightly integrated parallel printing architectures. A cross process charge uniformity scanner may include at least one micro-electro-mechanical based electrostatic voltmeter device for measuring surface charge at a plurality of locations along the length of the photoreceptor. The charge uniformity scanner may allow the xerographic printing apparatus to initiate charge device cleaning and/or control the intensity of the charge applied to the surface of the photoreceptor. Exemplary embodiments may include an electrostatic voltmeter moveably mounted along the length of the photoreceptor in the fast scanning direction, or may include a plurality of electrostatic voltmeters disposed at spaced apart locations along the length of the photoreceptor.

Abstract: To provide an electric potential measuring device which is useful in realizing size reduction, high sensitivity, and high reliability. The electric potential measuring device includes: an oscillating device which includes torsion springs, and an oscillating body axially supported by the springs to oscillate; and signal detecting unit which is located on a surface of the oscillating body. A capacitance between the detection electrode and a surface of an electric potential measuring object is varied by varying a distance therebetween by the oscillating device, whereby an output signal appearing on the detection electrode is detected.

Abstract: A modular keypad assembly for use with a projection device is provided. This modular keypad assembly may include a user input through which a user may operate the projection device. Such a modular keypad assembly may include a elastomer keypad, a keypad support plate; and a keypad circuit board.

Abstract: A system and method for controlling a xerographic printer includes a subsystem for carrying out a function of the xerographic printer and affecting an electric field of a component. The system and method further include a bias transfer roll voltage operated in a constant current mode, and a voltage evaluator coupled to the biased transfer roll for measuring a change in a level of voltage of the bias transfer roll as the component affected by the subsystem passes through a nip region near the bias transfer roll for determining operability of the subsystem.

Abstract: An improved modulator assembly of an electrostatic voltmeter for an electrophotographic process. A modulator base of the modulator assembly having accurate configuration and built in design features which simplify manufacture and assembly of the modulator assembly and electrostatic voltmeter. The modulator base includes reference mounting surfaces which provide accurate orientation and alignment of the modulator assembly during assembly, air purge grooves which provide enhanced air purging of contaminants from the modulator assembly, and shielding areas which maximize the signal to noise. The modulator base provides simplified construction of a modulator assembly for an electrostatic voltmeter having enhanced performance and robust functionality.

Abstract: Method and apparatus for controlling amplifier gain, e.g., as used in ESV of a xerographic copier, has a light source, e.g., an LED, optically coupled to a gain control light dependent resistor (LDR). The LDR can be in a negative feedback loop around an amplifier. There is a voltage sensing probe located near the photoreceptor belt of the copier and coupled to an input of the amplifier.

Abstract: A contactless process for detecting electrical patterns on the outer surface of a member comprising providing a member having a charge pattern on an outer surface, repetitively measuring the charge pattern on the outer surface of the member with an electrostatic voltmeter probe maintained at a substantially constant distance from the surface, the distance between the probe and the imaging member being slightly greater than the minimum distance at which Paschen breakdown will occur to form a parallel plate capacitor with a gas between the probe and the surface, the frequency of repetition being selected to cause all time dependent signals to fall out of phase by a predetermined amount, and averaging the out of phase time dependent signals over a sufficient number of measuring repetitions to eliminate the time dependent signals. In one embodiment, the contactless process detects surface potential charge patterns in an electrostatographic imaging member.

Abstract: In a surface potential measuring apparatus for measuring a potential configuration by moving a photosensitive body of an image forming apparatus of electrophotographic type and at least one potential sensor relative to each other and by generating dielectric current in the potential sensor due to change in potential on a surface of the photosensitive body and by analyzing the dielectric current, a width of a detecting portion of the potential sensor is smaller than a width of the change in potential to be measured, and a sectional shape of the detecting portion in a plane perpendicular to the surface of the photosensitive body and parallel to the relative movement direction does not include any edge.

Abstract: An electrometer probe is used in an electrophotographic apparatus as part of a process control system to measure charge on a photoconductive film belt. This measurement is used to control voltage level or other process parameter of the electrophotographic process. The probe is supported in an electrometer probe holder so that a sensor aperture of the probe is at a fixed distance from the film belt. In order to ensure proper operation of the electrometer probe, a method and an apparatus for independently calibrating the electrometer probe is provided. A curved plate is provided on the electrometer probe holder. The plate is mounted at the same spacing from the probe aperture as the film belt. This plate has a receptacle for the service person's test lead to attach. The other end of the test lead is attached to a test point for the toning station bias supply. The probe may be reoriented on the probe holder to position the probe aperture at the fixed distance to the plate.

Abstract: A contacting electrostatic voltmeter suitable for sampling positive or negative potentials on an electrostatically charged surface. The electrostatic voltmeter includes a selectively controllable actuation mechanism that enables the use of a contacting electrostatic voltmeter to sample the surface of an electrostatically charged member, moving relative thereto, within a predetermined space. The invention finds particular use in a printing system, where it enables charge monitoring during printing yet avoids disturbance to charged latent image areas on the imaging member.