Abstract: Printheads and printers are described herein. In one example, a printhead includes a number of drop generators disposed in a first array and a second array. The drop generators in both the first array and the second array are spaced one dot pitch apart perpendicular to the motion of a print medium, and alternate between a high drop weight (HDW) drop generator and a low drop weight (LDW) drop generator. Each drop generator in the first array is in a line of the motion of the print medium with a corresponding drop generator in the second array, wherein each HDW drop generator in the first array is in line with an LDW drop generator in the second array, and each LDW drop generator in the first array is in line with an HDW drop generator in the second array.

Abstract: Thermal inkjet printing wherein a printhead has ink ejection elements which are energizable by electrical pulses of a given energy with fire pulses of an amplitude (V) and a fire pulse width (fp). A printer controller sends commands to the printhead to spit ink drops, one or more temperature sensors coupled to the printhead measure a temperature of the printhead, and a calibration component coupled to the temperature sensor variably adjusts the fire pulse energy provided to the having ink ejection elements of the printhead.

Abstract: In some examples, a fluid nozzle includes an aperture comprising a first lobe that is shaped as an ellipse, and a second lobe that has a non-circular shape and has a different size than a size of the first lobe. The fluid nozzle further includes protrusions between the first and second lobes extending inward and forming a throat between the first and second lobes.

Abstract: Printheads and printers are described herein. In one example, a printhead includes a number of drop generators disposed in a first array and a second array. The drop generators in both the first array and the second array are spaced one dot pitch apart perpendicular to the motion of a print medium, and alternate between a high drop weight (HDW) drop generator and a low drop weight (LDW) drop generator. Each drop generator in the first array is in a line of the motion of the print medium with a corresponding drop generator in the second array, wherein each HDW drop generator in the first array is in line with an LDW drop generator in the second array, and each LDW drop generator in the first array is in line with an HDW drop generator in the second array.

Abstract: A fluid ejection device includes a fluid slot, a fluid ejection chamber communicated with the fluid slot, a drop ejecting element within the fluid ejection chamber, a fluid circulation channel communicated at a first end with the fluid slot and communicated at a second end with the fluid ejection chamber, and a particle tolerant architecture within the fluid circulation channel at the second end.

Abstract: An Inkjet nozzle includes an aperture with a noncircular opening substantially defined by a polynomial equation. A droplet generator is also described which includes a firing chamber fluidically coupled to a fluid reservoir a heating resistor and a nozzle. The nozzle includes an aperture forming a passage from the firing chamber to the exterior of the droplet generator through a top hat layer. The nozzle is defined by a closed polynomial and has a mathematically smooth and mathematically continuous shape around aperture's perimeter wall, with two protrusions extending into the center of the aperture.

Abstract: Printing methods and systems are described herein. In one example, a method includes rasterizing a document to create color rasters and linearizing the color rasters to create high drop weight (HDW) planes and low drop weight (LDW) planes. HDW and LDW halftone planes are created from the HDW and LDW planes. The HDW and LDW halftone planes are masked to create HDW and LDW printhead maps, and the HDW and LDW printhead maps are merged into print data. The print data is sent to a number of printheads.

Abstract: A fluid ejection device includes a fluid slot, a fluid ejection chamber communicated with the fluid slot, a drop ejecting element within the fluid ejection chamber, a fluid circulation channel communicated at a first end with the fluid slot and communicated at a second end with the fluid ejection chamber, a fluid circulating element within the fluid circulation channel, and a particle tolerant architecture within the fluid circulation channel at the second end.

Abstract: An inkjet nozzle includes an aperture with a noncircular opening substantially defined by a polynomial equation. A droplet generator is also described which includes a firing chamber fluidically coupled to a fluid reservoir, a heating resistor and a nozzle. The nozzle includes an aperture forming a passage from the firing chamber to the exterior of the droplet generator through a top hat layer. The nozzle is defined by a closed polynomial and has a mathematically smooth and mathematically continuous shape around aperture's perimeter wall, with two protrusions extending into the center of the aperture.

Abstract: A fluid ejection device includes a substrate; a plurality of resistors on the substrate with separation of between 4 and 8 microns between adjacent resistors; an adhesion layer applied over the plurality of resistors; and a layer of silicon carbide (SiC) applied directly over the adhesion layer such that the silicon carbide is between adjacent resistors. A method of forming a fluid ejection device includes forming resistors and conductive traces attached to a substrate; depositing an adhesion layer over the resistors; depositing a silicon carbide (SiC) coating directly over the adhesion layer; and forming an epoxy layer over silicon carbide layer.

Abstract: A printhead of a printer includes a nozzle plate having a first layer, a second layer, and an intermediate channel. The first layer can have at least one fluid chamber for holding an immiscible fluid, and a plurality of ejection fluid chamber for holding an ejection fluid. The second layer can have a plurality of ejection fluid nozzles, one ejection fluid nozzle being in fluid communication with one ejection fluid chamber. The intermediate channel can form a passage between the first layer and the second layer. Further, the intermediate channel is in fluid communication with the fluid chambers to carry the immiscible fluid from the fluid chambers towards each of the ejection fluid nozzles for forming a layer of the immiscible fluid over the ejection fluid chambers to maintain the printhead.

Abstract: According to an example, a fluid ejection device may include a fluid feed slot, a plurality of fluid ejection chambers in fluid communication with the fluid feed slot, a plurality of drop ejecting elements, in which a drop ejecting element of the plurality of drop ejecting elements is positioned within each of the plurality of fluid ejection chambers, a fluid circulation channel in fluid communication at a first end of the fluid circulation channel with the fluid feed slot and in fluid communication at multiple second ends of the fluid circulation channel with the plurality of fluid ejection chambers, and a fluid circulating element within the fluid circulation channel. The fluid ejection device may also include a bubble dissipating structure positioned within the fluid circulation channel outside of the plurality of fluid ejection chambers.

Abstract: In some examples, a fluid nozzle includes an aperture comprising a first lobe that is shaped as an ellipse, and a second lobe that has a non-circular shape and has a different size than a size of the first lobe. The fluid nozzle further includes protrusions between the first and second lobes extending inward and forming a throat between the first and second lobes.

Abstract: A printer is disclosed herein. The printer has a printhead having a plurality of ink nozzles for ejecting ink, a servicing mechanism for capturing the ejected ink from the ink nozzles, to service the printhead, and a control device coupled to the printhead and the servicing mechanism for regulating the servicing. As part of the regulation, the control device continues feeding a substrate towards the printhead during an idle period. The idle period of the printhead can be a duration when printing on the substrate is suspended. Further, the control device regulates ejection of ink from the ink nozzles towards the substrate during the idle period and operates the servicing mechanism during the idle period. In an example, the servicing mechanism captures the ink before the ink reaches the substrate.

Abstract: A fluid ejection device includes a fluid slot, a fluid ejection chamber communicated with the fluid slot, a drop ejecting element within the fluid ejection chamber, a fluid circulation channel communicated at a first end with the fluid slot and communicated at a second end with the fluid ejection chamber, a fluid circulating element within the fluid circulation channel, and a particle tolerant architecture within the fluid circulation channel at the second end.

Abstract: In some examples, a printhead can include a main printer fluid line, a firing chamber in fluid communication with the main printer fluid line to receive printer fluid from the main printer fluid line, and a resistor positioned in the firing chamber. The resistor can, for example, receive an electronic current to cause the resistor to heat up and eject printer fluid droplets from the printhead. The printhead can further include a photolithographically fabricated check valve positioned in the firing chamber. The check valve can, for example, be openable to allow filling of the firing chamber with printer fluid and closeable to at least partially seal the main printer fluid line from printer fluid blowback caused by the resistor.

Abstract: Printheads and printers are described herein. In one example, a printhead includes a number of drop generators disposed in a first array and a second array. The drop generators in both the first array and the second array are spaced one dot pitch apart perpendicular to the motion of a print medium, and alternate between a high drop weight (HDW) drop generator and a low drop weight (LDW) drop generator. Each drop generator in the first array is in a line of the motion of the print medium with a corresponding drop generator in the second array, wherein each HDW drop generator in the first array is in line with an LDW drop generator in the second array, and each LDW drop generator in the first array is in line with an HDW drop generator in the second array.

Abstract: Printing methods and systems are described herein. In one example, a method includes rasterizing a document to create color rasters and linearizing the color rasters to create high drop weight (HDW) planes and low drop weight (LDW) planes. HDW and LDW halftone planes are created from the HDW and LDW planes. The HDW and LDW halftone planes are masked to create HDW and LDW printhead maps, and the HDW and LDW printhead maps are merged into print data. The print data is sent to a number of printheads.

Abstract: Printheads and methods for forming printheads are described herein. In one example, a printhead includes a single resistor window in a conducting layer within the printhead. The printhead also includes a number of resistors formed in a resistor film deposited over the single resistor window. The resistors have two different widths, and each of the two different widths ejects a different droplet size when energized.

Abstract: Printheads and methods for forming printheads are described herein. In one example, a printhead includes a number of drop generators, wherein a pitch between each adjacent drop generator is substantially the same, and the drop generators alternate between a high drop weight (HDW) drop generator and a low drop weight (LDW) drop generator. The printhead also includes a flow channel from an ink source leading into an ejection chamber associated with each drop generator, wherein the flow channel comprises an inflow region proximate to the ink source, wherein an area of the inflow region is adjusted to control the flux of ink into the ejection chamber.