How does a piezoelectric inkjet printhead create droplets for printing?
1 Answer
A piezoelectric inkjet printhead is a type of technology used in inkjet printers to create and eject droplets of ink onto paper or other surfaces to create images, text, and graphics. The principle behind a piezoelectric inkjet printhead is the utilization of the piezoelectric effect, which is the ability of certain materials to generate an electric charge when mechanical stress is applied to them. In this context, the piezoelectric material changes shape when an electric field is applied to it, leading to the generation of pressure that expels ink droplets.
Here's a step-by-step explanation of how a piezoelectric inkjet printhead creates droplets for printing:
Ink Reservoir: The printhead contains an ink reservoir that holds the ink that will be used for printing.
Nozzle Plate: The printhead also has a nozzle plate with tiny nozzles through which the ink droplets are ejected. These nozzles are typically micrometers in size and are arranged in a precise pattern.
Piezoelectric Elements: Behind each nozzle, there is a tiny piezoelectric element. This element is made from a piezoelectric material, usually a ceramic or polymer.
Electric Pulse Application: When a printing command is given to the printer, a specific electric pulse is applied to the piezoelectric element corresponding to the nozzle from which a droplet needs to be ejected.
Piezoelectric Effect: The applied electric pulse causes the piezoelectric material to change shape rapidly. This deformation generates a mechanical pressure wave within the ink chamber behind the nozzle.
Pressure Wave Transmission: The pressure wave travels through the ink in the chamber and reaches the ink meniscus (the curved surface of the ink in the nozzle), causing it to deform and break off into a droplet.
Droplet Ejection: The sudden detachment of the ink droplet from the nozzle occurs due to the pressure created by the piezoelectric element's deformation. The size of the droplet is controlled by the duration and strength of the electric pulse applied to the piezoelectric element.
Recovery: After the droplet is ejected, the piezoelectric element returns to its original shape, and the ink meniscus retracts to its equilibrium position. The nozzle is ready to repeat the process for the next droplet.
Image Formation: By precisely controlling the timing and sequence of the piezoelectric pulses for different nozzles, the printhead can create a pattern of droplets on the printing surface, forming the desired image or text.
This process is repeated rapidly for each nozzle in the printhead, allowing for high-resolution and fast printing capabilities. Piezoelectric inkjet printheads offer advantages such as the ability to work with a wide range of inks, including those with different viscosities, and precise control over droplet size, which contributes to print quality.
Here's a step-by-step explanation of how a piezoelectric inkjet printhead creates droplets for printing:
Ink Reservoir: The printhead contains an ink reservoir that holds the ink that will be used for printing.
Nozzle Plate: The printhead also has a nozzle plate with tiny nozzles through which the ink droplets are ejected. These nozzles are typically micrometers in size and are arranged in a precise pattern.
Piezoelectric Elements: Behind each nozzle, there is a tiny piezoelectric element. This element is made from a piezoelectric material, usually a ceramic or polymer.
Electric Pulse Application: When a printing command is given to the printer, a specific electric pulse is applied to the piezoelectric element corresponding to the nozzle from which a droplet needs to be ejected.
Piezoelectric Effect: The applied electric pulse causes the piezoelectric material to change shape rapidly. This deformation generates a mechanical pressure wave within the ink chamber behind the nozzle.
Pressure Wave Transmission: The pressure wave travels through the ink in the chamber and reaches the ink meniscus (the curved surface of the ink in the nozzle), causing it to deform and break off into a droplet.
Droplet Ejection: The sudden detachment of the ink droplet from the nozzle occurs due to the pressure created by the piezoelectric element's deformation. The size of the droplet is controlled by the duration and strength of the electric pulse applied to the piezoelectric element.
Recovery: After the droplet is ejected, the piezoelectric element returns to its original shape, and the ink meniscus retracts to its equilibrium position. The nozzle is ready to repeat the process for the next droplet.
Image Formation: By precisely controlling the timing and sequence of the piezoelectric pulses for different nozzles, the printhead can create a pattern of droplets on the printing surface, forming the desired image or text.
This process is repeated rapidly for each nozzle in the printhead, allowing for high-resolution and fast printing capabilities. Piezoelectric inkjet printheads offer advantages such as the ability to work with a wide range of inks, including those with different viscosities, and precise control over droplet size, which contributes to print quality.