摘要:
A packet switch includes a multiple of bidirectional ports that are each connected by dedicated signal paths to a multiple of memory subsystems that in turn are connected to shared memory within the switch. The signal path from each port carries a fragment of a data stream between the port and each memory subsystem. The ports send and receive data stream fragments in parallel from the memory subsystems. This parallel action reduces the bandwidth required of a memory subsystem by dividing the port's data stream among the multiple memory subsystems. In storing data for forwarding to another port, each memory subsystem selects on a time division basis in parallel the data stream fragments from the same port and stores them in memory. In retrieving data from memory for a port, each memory subsystem selects on a time division basis in parallel the same port to receive the data stream fragments read from memory. The bit width of the signal paths between the ports and memory subsystems is reduced by sending smaller, individual data stream fragments between ports and memory subsystems and sending larger, aggregate data stream fragments between memory subsystems and memory. Within each memory subsystem are modules that combine individual data stream fragments into aggregate data stream fragments for storage in memory and modules that split aggregate data stream fragments read from memory into individual data stream fragments for transmission to ports.
摘要:
A precision belt hole sensor and associated conditioning circuitry provides precise trigger signals that enable synchronous printing in a color printer. An image bar recording system, which, in a preferred embodiment, utilizes a plurality of LED image bars, forms a plurality of latent images on a moving photoreceptor which may subsequently be developed in different colors. A pair of sensors associated with each printbar views illuminated pixels at the end of a printbar, through a pair of oppositely aligned photoreceptor holes. The signals detected by the sensor are amplified and processed to provide inputs to a comparitor circuit which generates an output signal at a time which precisely defines the passage of the trailing edge of the hole, past the sensors. The signal from the comparitor is used to accomplish skew registration of the printbar and to provide sync signals to enable precise formation of the leading edge of the associated image frame.
摘要:
The phosphor light output of a fluorescent lamp is controlled and optimized. The phosphor light output of the lamp corresponds to a particular level of either the vapor mercury or rare fill gas contained within the lamp envelope. This gas emission level is initially determined for a given system; a monitoring circuit thereafter detects any deviation from this level, generates a signal and sends it to a controller. The controller adjusts the operation of a mercury cold spot temperature-regulating device causing the cold spot temperature to increase or decrease until the optimum temperature and hence lamp phosphor light output is reestablished.
摘要:
.[.A symmetrical light intensity distribution profile is achieved by placing a pair of similar asymmetrical linear DC gas discharge lamps in parallel position but opposed in polarity. The individual asymmetrical distributions of the lamps combine in a symmetrical total intensity distribution. A desired "butterfly" or other intensity distribution profile can be achieved..]. .Iadd.The invention relates to an illumination system which provides nonuniform illumination along an object plane in the dimension of an illumination source which includes two linear lamps. The lamps have their anodes and cathodes connected in reverse fashion relative to each other; each lamp provides its own asymmetrical light output distribution pattern but the resultant output of both lamps is a symmetrical pattern which provides the characteristic nonuniform illumination on the object plane. .Iaddend.
摘要:
A symmetrical light intensity distribution profile is achieved by placing a pair of similar asymmetrical linear DC gas discharge lamps in parallel position but opposed in polarity. The individual asymmetrical distributions of the lamps combine in a symmetrical total intensity distribution. A desired "butterfly" or other intensity distribution profile can be achieved.
摘要:
Methods and associated hub arrangements are described for use in diagnosis and recovery in high performance digital loops such as, for example, those seen in Fibre Channel systems. In one system having a hub configured for interconnection of a plurality of stations as part of a digital system such that digital data flows between the stations based on operational status of the system, an arrangement forms part of the hub which arrangement is connectable at points within the hub and between at least two different pairs of the stations for monitoring certain characteristics of the data in a way which provides for non-invasive identification of one or more conditions related to the operational status of the system.
摘要:
Arrays of light emitting diodes, and LED printbars and electrophotographic marking machines that use arrays of light emitting diode, that have active area geometries that produce compact irradiance profiles. Compact irradiance profiles are achieved by placing the diode electrodes along the outer periphery of the light emitting active areas. When used with gradient index lenses, such light emitting diodes produce light spots having more compact irradiance profiles. When such light emitting diodes and gradient index lenses are incorporated into LED printbars, and when those printbars are used in expose stations of electrophotographic marking machines, improved composite images can result.
摘要:
An apparatus for positional tracking a moving photoconductive belt and adjusting an imager in an electrophotographic printing machine to correct for alignment errors when forming a composite image. Registration errors are sensed by developing an appropriate set of target marks, detecting the target marks, and controlling the position of the imager.
摘要:
A single pass, hybrid ROS/print bar system provides a plurality of latent images which may subsequently be developed in different colors. A ROS unit is initially aligned so that each scan line is registered in the process direction. The alignment is accomplished by forming a pair of opposed V-shaped apertures in the surface of the belt and detecting scan line cross-over of the legs of the V. These cross-overs are manifested as two sets of pulses generated by sensors associated with each target leg. The time differences between pulse sets are compared and the scan line is rotated until the time differences are equal. Once the ROS is registered for skew, one or more print bars are registered by enabling non-image pixels and comparing the output generated by detectors when the lit pixels are viewed through the V-shaped aperture.
摘要:
A printing system operating in a charged area development environmental utilizes a high resolution image print bar in cooperation with a low resolution image discharge bar to expose a charged surface of a photoreceptor with a minimum of stress being applied to the high resolution bar. The high resolution bar is addressed from an image data source so as to expose areas of the photoreceptor which correspond to informational areas of the image being printed. The low resolution bar is addressed from the same data source so as to discharge the photoreceptor surface in non-informational areas such as background areas and interimage areas. In a preferred embodiment, both the high and the low resolution bars are LED arrays located in a common exposure station.