Fluidic structures

A microfluidic method comprising:

• receiving fluid from or near a first plate-like structure through an inlet opening of a photo-defined ducting structure extending between the first plate-like structure and a second plate-like structure;
• flowing the fluid through a duct in the ducting structure;
• and
• providing the fluid to or near the second plate-like structure through an outlet opening of the ducting structure.

Fluidic apparatus comprising:

• first and second plate-like structures;
• and
• two or more microstructures each extending a respective length between the first and second plate-like structures;
• each microstructure having a cavity defined therein that contains fluid during operation, the cavity having a maximum dimension perpendicular to the microstructure's length;
• the ratio of the microstructure's length to the cavity's maximum dimension being approximately two or more.

Fluidic apparatus comprising:

• a drop side assembly from which fluid exits the apparatus and a drive side assembly from which fluid is driven toward the drop side assembly;
• the drop side and drive side assemblies defining between them a plenum that holds fluid during operation;
• and
• at least one microstructure within the plenum and extending between the drop side and drive side assemblies;
• each microstructure having an inlet opening through which it receives fluid out of the plenum from or near the drive side assembly, an outlet opening through which it provides fluid to the drop side assembly, and a duct in which fluid flows after being received through the inlet opening and before being provided through the outlet opening;
• the drive side assembly including, for each microstructure, an actuator that controllably causes fluid to be received out of the plenum through the microstructure's inlet opening, to flow through the microstructure's duct, and to be provided through the microstructure's outlet opening to the drop side assembly and ejected therefrom as drops.

A printhead comprising:

• a drop side assembly from which drops are ejected from the printhead;
• a drive side assembly from which fluid is driven toward the drop side assembly;
• and
• an array of two or more freestanding polymer microstructures supported between the drop side and drive side assemblies;
• each microstructure having an inlet opening through which it receives fluid from or near the drive side assembly, an outlet opening through which it provides fluid to the drop side assembly, and a duct in which fluid flows after being received through the inlet opening and before being provided through the outlet opening;
• the drive side assembly including, for each microstructure, an actuator that controllably causes fluid to be received through the microstructure's inlet opening, to flow through the microstructure's duct, and to be provided through the microstructure's outlet opening to the drop side assembly and ejected therefrom as drops.

A method of producing a microfluidic structure, comprising:

• photo-defining a ducting structure having an inlet opening through which it can receive fluid, an outlet opening through which it can provide fluid, and a duct in which fluid can flow after being received through the inlet opening and before being provided through the outlet opening;
• and
• including the ducting structure in a microfluidic structure that also includes first and second plate-like structures;
• in the microfluidic structure, the ducting structures being positioned with its inlet opening on or near the first plate-like structure and its outlet opening on or near the second plate-like structure.