Abstract: There is disclosed a thermal printer system having a multiple channel laser print head which focuses closely spaced spots of laser light energy onto a dye donor element which moves at constant velocity relatively past the print head. These laser light spots respectively print multiple lines of an image a swath at a time by heat transfer of pixels or subpixels of dye from the dye donor element to a receiver element. A light source (such as an arc lamp) applies to the dye donor element one or more precisely positioned spots of light energy which elevate the temperature of the dye donor element substantially uniformly within a zone coincidently with and closely surrounding the laser light spots. The shape, the position and the power absorbed within the zone from the light source are carefully controlled. Thus the temperature within this zone is held to a substantially uniform value slightly below the vaporization temperature of the dye to be transferred from the dye donor element.

Abstract: An exposure head for use in an image recording apparatus includes a plurality of light-emitting elements such as LEDs or LDs supported on a support for emitting respective light beams, and a single optical system for focusing the light beams onto a recording medium. The support and the optical system are movable in unison in an auxiliary scanning direction along an image recording drum which is rotatable in a main scanning direction transverse to the auxiliary scanning direction and carries the recording medium wound therearound.

Abstract: In a recording apparatus with an ink jet print head which forms dots on a recording sheet by ink jets shot from an array of nozzles, a microcomputer determines whether a printing defect is a light printing defect caused by paper particles and dust adhering to the nozzles or a heavy printing defect caused by the entry of air bubbles into the ink flow paths. The determination is made on the basis of intervals of operating a print recovery button mounted on a chassis of the recording apparatus. For the light printing defect, the computer puts a cap member to the front face of the nozzles of the print head and applies a negative pressure to the nozzles, thereby to reduce the amount of ink emitted from the nozzles. For the heavy printing defect, the computer increases the amount of ink.

Abstract: A gray scale printer modulates an exposure source in both amplitude and duration such that the exposure source is actuated during the latest portion of each pulse time period. For exposure periods having actuation times that are very short relative to the decay period of the amplitude-modulating electronics, actuation time of the exposure source for very short exposure periods may be timed to end before the start of the decay period. If the amplitude modulating means includes electronics having a ramping up period before producing a stable output, the actuation of the exposure source occurs during each pulse time period only after the ramping up period has substantially expired.

Abstract: An image head in which storage time is shortened to ease block selection. The image head is provided with means for preventing the influence of storage time. For instance, minority carriers in the switching transistors for driving image blocks are extracted by amplification circuits. Another method is to drive the switching transistors in the non-saturation region to prevent accumulation of minority carriers. The image head is provided with block selection circuit comprising a shift register and a clock counter. The datum is set in the head data set bit of the shift register at the time of resetting. Whenever the clock counter counts clock signals for one image block, the counter will shift the datum by one bit. This datum drives the image blocks.

Abstract: The valve is operable with a bubble generator that provides a restricted flow of air bubbles into a reservoir of an ink-jet pen to relieve excessive back pressure in the pen. The valve includes housed operating liquid that closes the valve in the event that the pen is tipped out of an upright orientation. A hydrophobic air-porous vent is provided for permitting passage of air bubbles through the valve into the reservoir while prohibiting the flow of the operating liquid through the vent.

Abstract: Printing apparatus particularly suited to provide a hardcopy of an image produced by medical imaging equipment or the like. The apparatus produces an area modulation hardcopy having a large number of gray levels per area modulation cell (pixel) by generating in substantially adfacent columns units of subpixels called pels. The pels have an initial size that is increased by the addition of subpels referred to as slices.

Abstract: In a printer having P+X printing elements for printing pixels with a vertical center-to-center spacing R.sub.1 during a plurality of line scans, and a stepper motor for moving a record medium in increments R.sub.2 where R.sub.2 is greater than R.sub.1, all points addressable printing is obtained by a combination of movement of the record medium orthogonal to the line scan direction and shifting address signals applied to the print elements. The stepper motor moves the record medium a distance k.sub.2 R.sub.2 between successive line scans and address signals are applied to (n+k.sub.1)th . . . (n+k.sub.1 +P-1)th print elements to cause a shift k.sub.1 R.sub.1 such that the sum of the distance the record medium is moved before a line scan and the shift caused by the address signals during a scan is equal to PR.sub.1 where P is the number of print elements active during the preceding line scan, or equal to any desired integral multiple of R.sub.1 in other print modes.

Abstract: An image forming apparatus capable of readily changing the pixel density of an image to be formed on an image carrier and, therefore, stabilizing image reproduction. To change the pixel density, the apparatus turns on, among light emitting elements arranged in a higher density than input image data, a plurality of light emitting elements per pixel or by changing the number of light emitting elements per pixel and the turn-on time thereof.

Abstract: A high density surface emitting semiconductor LED or laser array is coupled with a driver circuit substrate for modulating the light emitted from the array. This modulated light is imaged by optical means onto a photosensitive recording medium of an opto-electronic line printer. The imaging optical means can be either a single or multiple lens system.

Abstract: A scanning device for an electronic photography printer which comprises a photosensitive drum, a rotary cylinder horizontally disposed and provided with spiral slits which are spaced from one another, an LED array horizontally penetrating the inside of the rotary cylinder and having a plurality of LEDs which are disposed on the LED array and each having a width of the same distance as the space between respective spiral slits of the rotary cylinder, a horizontal slit plate disposed between the photosensitive drum and the rotary cylinder and having a plurality of slits which are inclined on the basis of the horizontal line of the horizontal slit plate and spaced from one another, and a self-focus lens array horizontally disposed between the photosensitive drum and the horizontal slit plate.

Abstract: An optical printing head for an optical printing device includes a long board with aligned light emitting diode arrays having a plurality of light emitting areas mounted and fixed on the board thereof, a holder provided with a staged portion therein, a fixing by pressure means for fixing the board to the staged portion of the holder by pressure and a lens array held at a predetermined position with respect to the board by the holder. This arrangement allows an optical printing head to be made small in scale and easy to be assembled without deteriorating printing quality.

Abstract: A printhead, particularly a light emitting diode (LED) printhead, which has improved apparatus for distributing signals to individual printing elements, i.e. LEDs, that are used in the printhead. Specifically, this printhead contains a number of print element arrays, typically arrays of light emitting diodes, and a corresponding number of drive circuits all of which are mounted to a common member, this member illustratively being a metallic stiffener plate. Each of the drive circuits is connected to a corresponding one of the print element arrays. All the print element arrays are typically situated in a co-linear orientation transversely along the member with the drive circuits co-linearly arranged along a side of the arrays.

Abstract: A print head operated on a time sharing basis. Print data are transferred from the outside into the print head in synchronization of clock pulses. The print head stores the print data in a shift register, detects input of print data for one print block portion on the basis of the number of clock pulses, then paralleltransfers the print data in the shift register to a latch circuit and at the same time shifts the print block by one block. When high-speed transfer is possible, the print head releases the external central processing unit or the like from the print head itself for a period from the input of print data of one block portion till the completion of the processing of the block. Moreover, the print head realizes mirror image printing by means of reversal of the order of the print blocks in the print head and reversal of print data in print blocks.

Abstract: A dynamic driving type optical printing head comprising a plurality of LED elements divided into a plurality of groups, wherein the LED elements are driven in time-division by groups, comprises a plurality of LED blocks arranged along the scanning direction on the head substrate, wherein each of the LED blocks comprises a plurality of LED elements arranged in the scanning direction; a plurality of wiring blocks arranged along the array of the LED blocks, wherein each of the wiring blocks comprises a plurality of selecting signal lines; and one or more data drivers; wherein each of the LED elements is connected to the corresponding selecting signal line in the wiring block by wiring means, and the selecting signal line is connected to the data driver by wiring means, so that the plurality of LED elements in each of the LED groups are connected to the data driver individually to each other.

Abstract: A multibeam semiconductor laser array including n pieces of mutually independently drivable semiconductor laser elements which are arranged with a distance r between the elements in such a manner that light leaving centers of respective laser beams emitted from the semiconductor laser elements are aligned on a straight line. In the multibeam semiconductor laser array, the distance r is determined according to the following equation when a light emitting wave length of each of the semiconductor laser elements is expressed as .lambda. and a divergence angle of the laser beam in a direction of the straight line is expressed as .theta..sub.1 : ##EQU1## where n is an integer equal to or more than 2, .pi. is a circle ratio, I is an interlacing period which is a natural number mutually prime to n, and k is a spot diameter correction coefficient which is a real number in the range of 1.4 .ltoreq.k.ltoreq.1.8.

Abstract: An automatic system for cleaning a thermal inkjet printhead. A thermal inkjet cartridge and service station are provided within a printer unit. The service station is directly beneath the cartridge when it is not printing. Attached to the service station is a printhead wiper unit consisting of a single member or, in the alternative, dual members positioned against each other to form a capillary pathway therebetween. The cartridge includes a compartment having an opening therethrough and an absorbent member impregnated with cleaning solution When the cartridge is not printing, the wiper unit is aligned with the compartment containing the absorbent member and is in contact therewith.

Abstract: A light emitting region of light emitting elements is so configured as to extend in an elongated fashion along the direction of movement of a photosensitive drum to prevent the area of exposure in the direction of movement of the drum from becoming unreasonably small. The width of the light emitting region of the light emitting elements is reduced to restrain unreasonable expanse of emitted light beams. Further, arrangement is made to provide greater current density thereby to obtain increased light intensity, and the distribution of current is equalized to provide uniform light brightness. Through development of finer and more intense light beams in this way, it is possible to inhibit unreasonable expanse of light beams thereby to enable each single light emitting diode to provide sufficient exposure intensity. Thus, the width of continuously printed lines, the width of intermittently printed lines, and the diameter of each dot in one dot printing can be substantially equalized.

Abstract: A non-impact printer apparatus and method for recording on a medium that is moving at a variable rate. A plurality of recording elements arranged transverse to movement of the medium records respective pixels. Each pixel is formed by enabling each recording element a plurality of times during a pixel recording period. To maintain uniformity in pixel recording a duration for recording a sub-pixel and the number of sub-pixels per pixel are adjusted in accordance with the speed of the recording medium. The sum of the sub-pixel recording durations during a pixel recording period comprises the pixel exposure time.

Abstract: A method and apparatus are disclosed for scanning a receiving medium. The apparatus comprises a motor-driven lead screw which is used to advance a print head relative to a receiving medium supported on a rotatable drum. In order to overcome the problem of banding in an image produced by the apparatus as a result of a sinusoidal pitch error of the lead screw, the pitch error of the lead screw is broken up into a random pitch error. In another embodiment, the pitch error frequency is shifted to a higher frequency which is less sensitive to the human eye.