The inkjet printhead designed by Xaar in the UK consists of three main parts: a cover and ink channel made of PZT (lead and zirconium titanate) and a nozzle plate made of polyimide diaphragm. 

A schematic diagram of the section structure of the standard print head perpendicular to the direction of ink dripping. Figure 2 is a cross-sectional view of the basic structure of the PZT channel. 

Both images show in detail the structure of the ink channel and the shared wall, from which we can see that the structure of the channel is parallel to the wall, the upper half of the side wall of the channel has an aluminum electrode, and at the top of the wall there is a cover plate glued by a thin and hard layer of viscose. Ink is introduced into the catchment tube through atmospheric pressure, and the bottom cut of the cover plate determines the effective length of the channel. This structure is called "exciter". 

The connection of the electrical wire, as shown in the diagram, is at the back of the catchment tube, but different print head designs will have different connections. 

When the driving signal is introduced into the channel, the upper part of the shared wall produces shear motion, and at the same time, the lower part of the shared wall is forced to follow the upper half to move accordingly, so the channel wall forms a V-shaped spire, which increases the pressure in the channel. with the help of the change of pressure, the ink in the pipe is extruded out of the nozzle to form ink droplets. 

For duplex printing, the effective length of the channel and the diameter of the nozzle will be relatively large, so the ink spots will be very large. 

For grayscale printing, the effective length of the channel and the diameter of the nozzle will be reduced, many small ink droplets (with a variable number) will be ejected out of the channel quickly and continuously, and these continuous ink droplets will be ejected so fast that they will merge with each other during flight, so that ink dots can be resized on a pixel-based basis. In 360dpi printing, grayscale 8 is the most representative.