Abstract: A fluid ejection system may include a media transport assembly and a printhead assembly having a fluid ejection device opposite the media transport assembly. The fluid ejection device may include a drop ejecting element and a fluid ejection chamber containing the drop ejection element. The fluid ejection chamber has an inlet and an outlet for fluid circulation through the fluid ejection chamber across the drop ejecting element. A particle tolerant architecture is between the inlet and the drop ejecting element.

Abstract: Printheads and printers are described herein. In one example, a printhead includes a plurality of nozzles configured to eject ink drops of different sizes wherein a low drop weight (LDW) drop is ejected through a nozzle with a circular bore (CB), and a high drop weight (HDW) drop is ejected through a nozzle with a non-circular bore (NCB).

Abstract: A passivation stack can include a laminated film, including from 8 to 40 alternating layers of HfO2 and SiO2. The layers can individually have a thickness from 8 Angstroms to 40 Angstroms, and the laminated film can have a total thickness of 280 Angstroms to 600 Angstroms. The passivation stack can also include a barrier film of HfO2 having a thickness from 50 Angstroms to 300 Angstroms applied to the laminated film.

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: A passivation stack can include a laminated film, including from 8 to 40 alternating layers of HfO2 and SiO2. The layers can individually have a thickness from 8 Angstroms to 40 Angstroms, and the laminated film can have a total thickness of 280 Angstroms to 600 Angstroms. The passivation stack can also include a barrier film of HfO2 having a thickness from 50 Angstroms to 300 Angstroms applied to the laminated film.

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: A fluid ejection unit may include a fluid supply passage, a fluid circulation loop having a first segment extending from the fluid supply passage, a second segment extending from the fluid supply passage and a bend connecting the first segment and the second segment, a fluid ejector along the second segment, the fluid ejector comprising a fluid ejection orifice and a fluid actuator and a fluid bypass spaced from the fluid actuator and in parallel with the bend to connect the first segment and the second segment.

Abstract: A fluid ejection system may include a media transport assembly and a printhead assembly having a fluid ejection device opposite the media transport assembly. The fluid ejection device may include a drop ejecting element and a fluid ejection chamber containing the drop ejection element. The fluid ejection chamber has an inlet and an outlet for fluid circulation through the fluid ejection chamber across the drop ejecting element. A particle tolerant architecture is between the inlet and the drop ejecting element.

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: 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: Printheads and printers are described herein. In one example, a printhead includes a plurality of nozzles configured to eject ink drops of different sizes wherein a low drop weight (LDW) drop is ejected through a nozzle with a circular bore (CB), and a high drop weight (HDW) drop is ejected through a nozzle with a non-circular bore (NCB).

Abstract: An inkjet nozzle includes an aperture with a noncircular opening having a first segment substantially defined by a first polynomial equation and a second segment substantially defined by a second equation.

Abstract: Printheads and printers are described herein. In one example, a printhead includes a plurality of nozzles configured to eject ink drops of different sizes wherein a low drop weight (LDW) drop is ejected through a nozzle with a circular bore (CB), and a high drop weight (HDW) drop is ejected through a nozzle with a non-circular bore (NCB).

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: 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: 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.

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: 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.