Abstract: An apparatus in which the developability of electrostatically charged particles in a mixture of particulate material is measured. The apparatus includes a transparent member positioned closely adjacent to a developer roller of an electrophotographic printing machine. A brush of particles is formed adjacent the member in one mode of operation, while, in another mode of operation, a cloud of particles is formed adjacent the member. A portion of the charged portions are attracted to the member. A beam of energy is transmitted through the member with the internal angle of incidence being greater than the critical angle of incidence of the member. The intensity of the internally reflected beam is detected and a signal generated indicative of the quantity of charged particles adhering to the member.

Abstract: A high speed digital ionographic printer having a rotatable charge receptor, an ion source with ion discharge slot opposite the charge receptor, a cylindrical screen about the ion source composed of a conductive substrate with tiny holes and a photoconductive cover layer, parts of the screen riding against the charge receptor so that the screen rotates at the same velocity as the charge receptor, a screen charge corotron, and a laser writing beam which is scanned line by line across the moving screen to write latent eletrostatic images thereon which thereafter modulate the flow of ions through the slot in accordance with the latent electrostatic image written on the screen.

Abstract: A voltage measuring device in an electrostatographic arrangement having a photoreceptor member charged to a uniform voltage level prior to imagewise discharge, and including at least a first corotron having a corona producing coronode driven with an A.C. voltage source for neutralizing charge on a surface in the electrostatographic arrangement. A thin conductive wire electrode is arranged parallel and across the photoreceptor surface and parallel to the coronode, to derive a current proportional to the voltage on the photoreceptor surface. Voltage measurements may be taken as a known function of the current derived in the electrode.

Abstract: A multi-function printer employing a linear array of lenslets for transmitting, when in the COPY mode, image rays from the image original being copied to the moving photoreceptor of a xerographic system. To scan the image original, the platen is moved past the scan point whereat the lens array optical path intersects the platen. For operation in a READ mode, a linear reading array of photosensitive elements is disposed to one side of the optical path between the lens array and the photoreceptor, the longitudinal axis of the reading array being perpendicular to that of the lens array. A prism is inserted into the optical path to intercept the image rays transmitted by the lens array from the platen and transmit the image rays to the reading array where the image represented thereby is converted to electrical signals or pixels.

Abstract: An apparatus in which the developability of electrostatically charged particles in a mixture of particulate material is measured. The apparatus includes a pair of spaced-apart conductive plates through which at least a portion of the particulate mixture flows. One of the plates is transparent with a member being secured thereto. The transparent plate is electrically biased to attract charged particles thereto. A beam of energy is transmitted through the transparent plate and member. The intensity of the internally reflected beam is detected to provide a measurement of the quantity of charged particles adhering to the transparent plate.

Abstract: An apparatus in which the developability of electrostatically charged particles in a mixture of particulate material is measured. The apparatus includes a transparent member positioned closely adjacent to a developer roller of an electrophotographic printing machine. Electrostatically charged particles are attracted from the particulate mixture being transported by the developer roller to the member. A beam of energy is transmitted through the member. The intensity of the internally reflected beam is detected and a signal generated indicative of the quantity of charged particles adhering to the member.

Abstract: A dual mode reproduction machine or copier incorporating a full width read/write bar having at least one linear array of LEDs for selectively illuminating and scanning a document original in a read mode or exposing the copier photoreceptor in a write mode. A Selfoc lens array provides a lens element for focusing each LED, the rear/write bar and lens array being combined in a unitary structure mounted for selective movement between a read and write position.

Abstract: A multi-color printer using an additive color process to provide either partial or full color copies. Multiple scanning beams, each modulated in accordance with distinct color image signals, are scanned across the printer's photoreceptor at relatively widely separated points, there being buffer means provided to control timing of the different color image signals to assure registration of the color images with one another. Each color image is developed prior to scanning of the photoreceptor by the next succeeding beam. Following developing of the last color image, the composite color image is transferred to a copy sheet.In an alternate embodiment, an input section for scanning color originals is provided. The color image signals output by the input section may then be used by the printing section to make full color copies of the original.

Abstract: A rod-like light collector for collecting light reflected from a photoconductive surface bearing a developed image and scanned by a flying spot scanner with a central core of a relatively rigid transparent material encased by a cladding material having an index of refraction lower than that of the core and an outer light diffusing coating, a portion of which is removed to provide a slit-like aperture for receiving light reflected from the photoconductive surface. The shape of the light receiving aperture may be varied uniformly along the length of the collector with the size of the aperture at the center at a minimum. And, a slit-like axial section of the cladding material opposite the light receiving aperture may be replaced by a highly reflecting, light diffusing coating.

Abstract: A multi-mode electrostatographic printing machine. A first latent image is recorded on a photoconductive member. The first latent image is transferred to a dielectric sheet. Subsequent to this transfer, the sheet is moved to a position where a second image is formed on the dielectric sheet by a stylus array having a plurality of individually actuatable stylii. Operator controls allow either of or both the latent images to be formed on the dielectric sheet. The multi-mode of operation can be extended to include a third image forming device for causing a third latent image to be recorded on the photoconductive member and subsequently transferred to the dielectric sheet. The operator controls are similarly extended to allow any combination of the three images to be formed on the dielectric sheet.

Abstract: A combination xerographic/flying spot scanning apparatus wherein xerographic images produced by the xerographic section are scanned following development by the scanning beam of the scanning section to produce image signals or pixels representative of the image scanned. To accommodate changes in the apparatus due to use and wear on the components, a test image is produced in the interdocument area, and following development, scanned by the scanning beam. The signals produced from the test image are utilized to update the threshold level at which image signals produced by the apparatus scanning section are processed.

Abstract: A triple function image processing system incorporating, for operation in a first COPY mode, a light/lens imaging system for imaging originals at a viewing station or platen to produce latent electrostatic images thereof on a photoconductive surface. The electrostatic images are developed and transferred to a copy substrate material as in conventional xerographic systems. A flying spot light beam is provided in a second WRITE mode, the flying spot beam writing images on the photoconductive surface in response to image signals input thereto. In this mode of operation, the beam impinges on the photoconductive surface at a location upstream of the developing device. And, in a third READ mode, the beam is impinged on the photoconductive surface downstream of the developing device to scan images developed on the photoconductive surface. The scattered light is collected and converted to image signals representative of the image scanned.

Abstract: A triple function image processing system incorporating, for operation in a first COPY mode, a light/lens imaging system for imaging originals at a viewing station or platen to produce latent electrostatic images thereof on a photoconductive surface. The electrostatic images are developed and transferred to a copy substrate material as in conventional xerographic systems. A flying spot light beam is provided in a second WRITE mode, the flying spot beam writing images on the photoconductive surface in response to image signals input thereto. In this mode of operation, the beam impinges on the photoconductive surface at a location upstream of the developing device. And, in a third READ mode, the beam is impinged on the photoconductive surface downstream of the developing device to scan images developed on the photoconductive surface. The scattered light is collected and converted to image signals representative of the image scanned.

Abstract: An electrophotographic printing machine in which a single processing station performs the functions of charging a photoconductive member and developing an image recorded thereon. In addition, this processing station may perform the additional function of transferring the powder image from the photoconductive member to the copy sheet.

Abstract: A development apparatus in which the donor member has a pattern of depressed regions therein. The donor member moves developer material into contact with a sheet of support material disposed adjacent an electrostatic latent image recorded on a photoconductive surface. Inasmuch as the donor member has a pattern of depressed regions therein, the developer material is deposited on the sheet of support material in a half-tone pattern.

Abstract: Photoelectrophoretic imaging system having an additional electrode for subjecting a film of photoelectrophoretic imaging suspension to an electric field at a potential above the corona threshold of the film prior to image exposure. The effect of the electric field and resulting current causes electrophoretic deposition of the imaging particles in the imaging suspension in a uniform layer to thereby eliminate or reduce background degradation in the final image formed.