{"id":2795,"date":"2018-05-07T09:00:14","date_gmt":"2018-05-07T09:00:14","guid":{"rendered":"https:\/\/imagexpert.wpengine.com\/?p=2795"},"modified":"2025-04-24T13:58:37","modified_gmt":"2025-04-24T13:58:37","slug":"what-is-a-waveform","status":"publish","type":"post","link":"https:\/\/imagex.lachancetesting.com\/ja\/what-is-a-waveform\/","title":{"rendered":"\u6ce2\u5f62\u3068\u306f\u4f55\u3067\u3059\u304b\uff1f"},"content":{"rendered":"
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An important part of an inkjet printing system is the waveform that is applied to the printhead, which is the driving force behind the drop ejection. The design of the waveform will directly impact the performance of the printer and print quality, but this waveform design is often not well understood. In this post we will discuss the fundamentals of the waveform – what waveforms are, how they work, and why they are a necessary part of your inkjet development. In the next post, you’ll find practical steps to go through the process of optimizing a waveform for your for your ink. Start with this article, and when you are ready to move on to editing your waveform, learn how to optimize one here<\/a>.<\/p>\n

WHY WAVEFORMS MATTER<\/h2>\n

The waveform is the electrical signal that is sent to each nozzle on the printhead that causes each individual drop to be fired. This electrical signal is sent to hundreds or thousands of individual nozzles simultaneously, thousands of times per second. The shape of the waveform signal will influence the size and speed of the drops. It also impacts the consistency of the jetting from one drop to the next, across the printhead, and over time. It also dictates the maximum speed that the printer can operate. The waveform holds a lot of power over the performance of the printer, especially for one setting tucked deep into the software that you might not even know exists.<\/p>\n

If drop size, jetting consistency, drop placement accuracy, printing speed, or some other requirement of your application demands a high level of performance, optimizing every last detail including the waveform matters. If you are working with a challenging fluid, whether or not it comes out of the printhead or not at all will be dictated by your waveform design. With the right tools, making small waveform changes that bring huge performance improvements is a simple, quick process.<\/p>\n

To showcase this, here is what one waveform setting change can do to the quality of your printing process. Both of these images are taken from the same printer, using the same ink, minutes apart. The only difference between them is a changing a single voltage setting in the waveform software.<\/p>\n


\nHigh speed drops, lots of satellites. This is suitable for a large throw distance application that is very forgiving to satellites, such as printing on textiles.<\/p>\n


\nReduced speed drops, no satellites. This is suitable for a short throw distance application where satellites are problematic, such as printed electronics.<\/p>\n

Using the wrong waveform for the wrong application will handicap your printing performance, leaving you to try to find formulation or mechanical solutions to overcome these setbacks. Waveform edits are much simpler, you just need to learn how to do it. Let’s get started!<\/p>\n

THE BASIC PRINCIPLES OF AN INKJET WAVEFORM<\/h2>\n

To help understand how a waveform works, let\u2019s take a look inside a nozzle chamber of a printhead. The image below depicts the jetting process known as fill-and-fire, which is common across many different printhead models. In this case, a stack of PZT (a piezoelectric ceramic material) deforms whenever voltage is applied to it, changing the volume of the ink chamber and causing the ink to move within it. If the ink moves enough, it will leave the nozzle as a drop. The means of applying this voltage to the PZT is the waveform.<\/p>\n

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\nIn our example, the PZT is extended only when voltage is applied, so there will be no deformation until the printhead is plugged in. Once powered, the printhead maintains a specific voltage, causing the PZT to extend and remain in its non-jetting position (Left). If the voltage is decreased, the PZT retracts and creates an expansion in the chamber, drawing ink into it (Center). To eject a drop, the voltage is returned to its original value, the chamber shrinks, and the excess ink is forced out (Right). This process repeats thousands of times per second across every nozzle on the printhead.<\/p>\n

The waveform is applied to the printhead through the electronics referred to as a printhead “controller” or\u00a0 “drive electronics”. These electronics send the signals and their software will have settings to control the shape of the signal. Here’s an example of a real waveform for a Dimatix printhead and Meteor drive electronics software for designing and applying it.<\/p>\n

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It is important to note that the actual shape of this pulse will vary with printhead design. Some printheads are driven by positive-going pulse, some by negative-going pulses, and some even go in both directions. Whichever way you\u2019re used to looking at it, there are some fundamental settings that determine the shape of the waveform.<\/p>\n