Microfluidic delivery systems for dispensing a fluid composition into the air comprising microfluidic die and at least one heating element that is configured to receive an electrical signal comprising a certain on-time and wave form to deliver a fluid composition into the air.

According to one embodiment, a tablet printing apparatus includes: a conveyer configured to convey a tablet along a line; an applicator head including a plurality of nozzles arranged in a direction crossing the conveyance direction of the tablet conveyed by the conveyer, configured to perform printing on the tablet by ejecting a liquid from the nozzles; and a controller configured to control the ejection of the liquid from the nozzles of the applicator head. The length of an array of the nozzles in a direction perpendicular to the conveyance direction is equal to or longer than the length of the tablet in the direction perpendicular to the conveyance direction. The controller is further configured to control switching of a nozzle used for printing on the tablet among the nozzles by a plurality of sections determined in advance.

A fluid ejection device includes a fluid slot, at least one fluid ejection chamber communicated with the fluid slot, a drop ejecting element within the at least one fluid ejection chamber, a fluid circulation channel communicated with the fluid slot and the at least one fluid ejection chamber, and a fluid circulating element communicated with the fluid circulation channel. The fluid circulating element is to provide on-demand circulation of fluid from the fluid slot through the fluid circulation channel and the at least one fluid ejection chamber.

The fluid ejection device includes a plurality of nozzles and a plurality of ejection chambers that includes a respective ejection chamber fluidically coupled to a respective nozzle. A plurality of inlet passages are fluidically coupled to the ejection chambers and input fluid to the ejection chambers at a first pressure. A plurality of outlet passages are fluidically coupled to the ejection chambers and output fluid from the ejection chambers at a second pressure that is less than the first pressure. Fluid circulates through the ejection chambers based on the pressure difference between the first and second pressure. The fluid ejection device also includes at least one micropump fluidically coupled to at least one ejection chamber to pump fluid through the at least one ejection chamber.

A die for a printhead is described herein. The die includes a number of fluid feed holes disposed in a line parallel to a longitudinal axis of the die, wherein the fluid feed holes are formed through a substrate of the die. The die includes a number of fluidic actuators, proximate to the fluid feed holes, to eject fluid received from the fluid feed holes. Circuitry on the die operates the fluidic actuators, wherein traces are provided in layers between adjacent fluid feed holes, connecting circuitry on each side of the fluid feed holes.

A die for a printhead is described herein. The die includes a number of fluid feed holes disposed in a line parallel to a longitudinal axis of the die, wherein the fluid feed holes are formed through a substrate of the die. A number of fluidic actuators are proximate to the fluid feed holes, to eject fluid received from the fluid feed holes A number of field-effect transistors are parallel to the fluid feed holes, where each of the fluidic actuators is powered by an associated field effect transistor. Logic circuitry to actuate the plurality of field-effect transistors is disposed on the die on an opposite side of the fluid feed holes from the field-effect transistors, wherein traces, disposed between the fluid feed holes, electrically couple the logic circuitry to the field-effect transistors. The die has a repeating structure comprising one fluid feed hole, two fluidic actuators, and two field-effect transistors placed at an interval of two times a dot pitch in a line along the die.

A fluid ejector includes a fluid ejection module having a substrate and a layer separate from the substrate. The substrate includes a plurality of fluid ejection elements arranged in a matrix, each fluid ejection element configured to cause a fluid to be ejected from a nozzle. The layer separate from the substrate includes a plurality of electrical connections, each electrical connection adjacent to a corresponding fluid ejection element.

The fluid ejection device includes a plurality of nozzles and a plurality of ejection chambers that includes a respective ejection chamber fluidically coupled to a respective nozzle. A plurality of inlet passages are fluidically coupled to the ejection chambers and input fluid to the ejection chambers at a first pressure. A plurality of outlet passages are fluidically coupled to the ejection chambers and output fluid from the ejection chambers at a second pressure that is less than the first pressure. Fluid circulates through the ejection chambers based on the pressure difference between the first and second pressure. The fluid ejection device also includes at least one micropump fluidically coupled to at least one ejection chamber to pump fluid through the at least one ejection chamber.

A die for a printhead is described herein. The die includes fluid feed holes disposed in a line parallel to a longitudinal axis of the die. The fluid feed holes are formed through a substrate of the die. Fluidic actuators are proximate to the fluid feed holes, to eject fluid received from the fluid feed holes. Field-effect transistors are parallel to the fluid feed holes. Each fluidic actuator is powered by an associated field effect transistor. Logic circuitry to actuate the field-effect transistors is disposed on an opposite side of the fluid feed holes from the field-effect transistors. Traces, disposed between the fluid feed holes, electrically couple the logic circuitry to the field-effect transistors. The die has a repeating structure including one fluid feed hole, two fluidic actuators, and two field-effect transistors placed at an interval of two times a dot pitch in a line along the die.

Fluid ejection devices with multiple activation modes are disclosed. An example printhead assembly includes a fluid ejection nozzle, a first resistor fluidically coupled to the fluid ejection nozzle, and a second resistor fluidically coupled to the fluid ejection nozzle. The example printhead also includes an addressing circuit to receive a nozzle address and an activation mode to activate the fluid ejection nozzle. The activation mode determines which of the first resistor and the second resistor are to be energized.