Abstract: A silicon rib waveguide that has a silicon nitride cladding layer of predetermined thickness to reduce optical loss of light propagating therethrough. An exemplary embodiment of the waveguide is fabricated by using a silicon-on-insulator structure having a single crystal silicon layer bonded to a silicon wafer with a layer of insulative material. An etch resistant masking layer is deposited on the outer surface of the single crystal silicon layer and patterned to produce vias therein. A RIE etching process is used through the vias in the masking layer to form at least one rib bounded by a pair of parallel trenches. The masking layer is removed and a silicon nitride cladding layer is deposited on the rib side and end walls and on the trenches.

Abstract: A non-interactive development system generates a toner cloud in a development zone by an AC biased stationary electrode positioned in contact with the back surface of a movable toned dielectric donor belt having a patterned electrode structure on the front surface thereof. The AC biased electrode produces AC fringe fields near the edges of the patterned electrode structure that cause the generation of a toner cloud for developing an electrostatic latent image. The donor belt is partially wrapped around a magnetic brush to produce a toner loading zone. Isolated patterned electrodes on the donor belt near the entrance region of the toner loading zone are biased to cause unloading of toner from the donor belt, while isolated electrodes near the exit region of the toner loading zone are biased to cause toner reloading of the donor belt.

Abstract: A toner removal apparatus for a reproducing machine has a cylindrical brush mounted for rotation in a closely fitting housing. The housing has an open side confronting a moving photoreceptor. Brush fibers extend through the housing open side into interfering contact with the photoreceptor and sweep toner therefrom. A slot in the housing parallel to the brush is connected to a vacuum source to draw air into the housing open side, through the brush fibers, and out the housing slot. First and second parallel bars are mounted on opposite sides of the housing slot and extend into contact with the brush fibers. The first bar compresses and then releases the brush fibers to flick toner therefrom. The second bar extends into the housing a lesser amount than the first bar and contacts the brush fibers without compression thereof, thereby providing an air seal, so that all of the air flows through the brush fibers.

Abstract: An ink jet printhead has an upper substrate containing a reservoir with ink inlet and a lower substrate having a linear array of droplet generating elements and addressing electrodes thereon. At least two layers of polymeric material are serially deposited and patterned over the droplet generating elements and addressing electrodes prior to mating the two substrates. The patterned polymeric layers define an elongated opening containing an array of posts therein and a plurality of channels, each channel containing a droplet generating element. One end of the channels is open to serve as nozzles and the other end is in communication with the elongated opening with the array of posts. After the two substrates are aligned and mated, the reservoir is in communication with the elongated opening, so that the ink from the reservoir is filtered prior to entering the channels by passing between and over the posts in the elongated opening.

Abstract: A thermal ink jet printhead for a printer has a temperature sensor attached thereto for monitoring the operating temperature thereof. A maximum printhead operating temperature is stored in a memory of the printer's control circuitry and, if the printhead temperature sensed by the temperature sensor during a printing operation exceeds the maximum operating temperature stored is the memory, a signal is generated indicating that the printhead has stopped ejecting ink droplets and must be checked for depriming or a depleted ink supply.

Abstract: A positionable wiper blade is positioned by a translatable carriage contact and clean a printhead nozzle face. The carriage translates a removable ink tank support structure with an attached ink jet printhead from a printing location to a non-printing location where the positionable wiper blade is located. A replaceable ink supply tank is installed on the support structure and replaced when the ink is depleted. The wiper blade is moved into wiping position by movement of the carriage and when the carriage is translated away from the non-printing location towards the printing location, the wiper blade cleans the printhead nozzle face and flicks the ink removed from the nozzle face into a backstop receptacle.

Abstract: A priming system for selectively priming one of the two printheads of a multicolor ink jet printer. When one of the printheads require periodic priming, the printheads are transported to the printer's maintenance station where individual caps are moved to cover the nozzle faces of the printheads. The priming system has two individual peristaltic pumps, each one of which is connected to a respective one of the caps. The two peristaltic pumps have a single mechanical input to drive selectively one of the pumps and not the other by a positionable swing gear. Each one of the pumps is adapted to prime only one of the printheads. The swing gear engages the drive gear of one pump when the direction of rotation of the input is clockwise and the swing gear engages the drive gear of the other pump when the direction of rotation of the input is counterclockwise.

Abstract: A liquid ink printer, depositing ink drops to form an image, in multiple printing resolutions, on a recording medium moving along a recording medium path. The liquid ink printer includes a pagewidth printbar, including an array of ink ejecting nozzles spaced at a predetermined resolution, aligned substantially perpendicular to the recording medium path, to eject the ink drops on the recording medium during movement of the recording medium along the recording medium path, a positioning device, coupled to the pagewidth printbar, to position the printbar at a plurality of discrete locations, and a controller, coupled to the printbar and to the positioning device, to cause the positioning device to position the printbar at the plurality of discrete locations as a function of the predetermined resolution.

Abstract: A printhead and method of fabrication thereof provides that the printhead reservoir has substantially the same cross-sectional ink flow area as the total cross-sectional area of the plurality of individual ink channels which interconnect the reservoir with the printhead nozzles. Since the flow area of the reservoir is substantially matched to the total flow area of the channels, the ink capacity of the reservoir is relatively low and the flow rate therethrough during a printing operation is relatively high. The small capacity of reservoir, together with the high ink flow rate therethrough, assures short ink residency time during printing, so that any exsolved air bubbles in the ink are swept away with subsequent ink droplet ejections during a printing operation and thus prevents any air bubbles present from coalescing into larger bubbles which can cause print quality defects.

Abstract: A drive transistor for a high resolution ink jet printhead having a pocket implant in the gate region of the device. The pocket implant enables a reduced source to drain spacing without loss of breakdown voltage. Accordingly, the size of the transistor may be reduced. Alternatively, this device is suitable for addressing 1200 spi resolution printheads. In one embodiment, the pocket implant extends about 1 .mu.m beyond the gate region towards the drain region. Both embodiments produce a graded drift region.

Abstract: An ink jet printhead is disclosed which has a heater plate containing the heating elements and driving circuitry means monolithographically formed on one surface thereof and the ink flow directing channel structure is formed on the heater plate using a layer of patternable polymeric material which, in one embodiment, is exposed using a mask to define the channel pattern then developed and cured. After curing, the patterned channel structure is polished to provide a smooth coplanar surface and a cover plate with an aperture therein is aligned and bonded to the channel structure to complete the printhead. The aperture serves as both ink inlet and a portion of the ink reservoir. The channels are open at one end and serve as the droplet ejecting nozzles, while the other ends are closed and extend beneath the cover plate aperture to provide a baffled portion of the ink reservoir and prevent cross-talk between the ink channels.

Abstract: A droplet-on-demand ink jet printer uses electrostatic tacking of a recording medium, such as paper, to achieve simultaneously precise holding of an aligned recording medium on a dielectric surface of a transport belt, thereby providing precise motion quality of the recording medium relative to the printer's printhead, and improved ink droplet placement on the recording medium. The transport belt is electrostatically charged with a charge of one polarity, so that an electrostatic pressure is generated which precisely holds the recording medium in an aligned position on the transport belt, after it is fed thereon, and concurrently induces a charge of opposite polarity on the ink droplets ejected by the printhead, thereby accelerating the droplets toward the recording medium.

Abstract: A preheater is placed between a supply tray station and a print zone of an ink printer. Power to the preheater is varied so that the preheater is heated to a fist relatively high temperature during the time that the recording medium is advanced from the supply station to the print zone. When the recording medium enters the print zone, the medium is moved at a slower indexing speed, and the power to the preheater is reduced to a second level. The result is a more uniform application of preheat to the recording medium.

Abstract: A method for seriatim feeding and aligning of a plurality of fluid seals spaced apart on a carrier member to a fixed location in a punch mechanism. After each fluid seal is aligned at the fixed location, the carrier member is gripped on opposing sides of the aligned fluid seal by a pair of clamps and, in one embodiment, the clamps lowered with the gripped portion of the carrier member therebetween. A set of parallel needles mounted in a plate located directly beneath the gripped portion of the carrier member penetrate the lowered portion of the carrier member and lift the fluid seal from the carrier member. The removed fluid seal is held atop the needle points for ease of access by a robotic installation mechanism which will pickup and place the fluid seal onto a device, such as an ink jet cartridge.

Abstract: An ink jet cartridge for use in an ink jet printer has replaceable ink supply tanks. The cartridge includes a housing with an integrally mounted printhead, at least one ink pipe connector protruding from a floor thereof, and internal passageways which interconnect the ink pipe connectors and printhead. The replaceable ink supply tanks, one for each color and each ink pipe connector, contain an ink saturated foam or needled felt member, an ink outlet port, and a filter element which covers the ink outlet port. When the ink supply tank is installed in the cartridge housing, the ink pipe connector extends through the outlet port of the tank and deforms the filter element into compressive contact with the foam or needled felt member. Whenever an ink depleted ink supply tank is replaced with a new ink supply tank, a fresh filter element is available for the cartridge, thus preventing degradation of the cartridge filters during the useful life of the cartridge.

Abstract: A method and apparatus for removing or relocating relatively small air pockets from the reservoirs of ink jet printheads through the use of a decompression technique. In one embodiment, an ink jet cartridge, after being filled with ink, is subjected to a relatively high vacuum by being placed in an evacutable container which is connected to a high vacuum source. The container may hold several cartridges for concurrent processing. In another embodiment, an accessory kit may be used to provide the same decompression process while the cartridge is installed in the printer and located at its maintenance station. The accessory kit could be incorporated into the printer.

Abstract: A Release Agent Management (RAM) system for a heat and pressure fuser apparatus utilized for fixing color toner images on substrates such as plain paper and transparency material such as Mylar.TM.. A donor/metering roll arrangement is provided with two oil metering blades, one of which is operative during two modes of operation and the other of which is operative during only one of the two modes of operation. During one mode of operation when color toner images are formed on a substrate such as plain paper, only one of the two blades is utilized. During a second mode of operation when color toner images are created on a transparent substrate such as Mylar.TM., both blades engage the surface of the metering roll so that a lesser amount of oil is ultimately conveyed to the surface of the heated fuser roll.

Abstract: A heat and pressure fuser and Release Agent Management (RAM) systems therefor. The RAM system deposits release agent material on toner images on a substrate such as plain paper. The RAM system includes a rigid metering roll and a pressure roll supported for pressure engagement to form a nip through which a substrate carrying the toner images passes with the toner images contacting the metering roll. Release agent material is applied to the metering roll from a supply with subsequent transfer primarily to the toner images on the substrate.

Abstract: A Nip Forming Fuser Roll (NFFR) fuser. The fuser is constructed to be self-stripping, that is, the roll contacted by the substrate carrying the toner images is fabricated from a relatively thick elastomeric material which under pressure exerted through contact of the nip forming members is sufficiently strained as the substrate passes in and out of the nip that the fuser roll is self-stripping. An external source of energy in addition to an internal source is used for elevating the surface temperature of the fuser roll member contacted by the toner image carrying substrate. A shield is provided for precluding contact of the external heat source by the substrate in the event of a misstrip. The shield which is fabricated from an infrared radiation transmissive polymer material is supported in intimate contact with the heated fuser member to minimize the presence of oxygen for minimizing the possibility of substrate combustion.

Abstract: An improved method for estimating toner usage in digital xerographic printers and copiers. The method is characterized by taking into account digital image dot spreading which results in the area of a pixel not being developed fully and some areas outside of the pixel being developed. Thus, the improved method takes into account the departure of a developed image from an ideal shape (i.e. square). To this end, the improved method compensates for departure of a developed image from an ideal shape. In carrying out the method estimated toner usage is based on pixel groupings rather than simple pixel counting.