Thermal Print Head Special Feature: Engineer Column – History of Thermal Print Head

History

1.Introduction

For many people, the term Thermal Print Head (TPH) may sound unfamiliar.
From the name, you might guess it has something to do with printers—and you’d be right.
While TPHs are well known to industry professionals and customers, they are actually used in many everyday applications, making them an interesting piece of printing technology for everyone.

2.Soft Copy and Hard Copy

Image information is generally classified as soft copy or hard copy. Soft copy refers to images displayed on screens and can be rewritten.
Hard copy, such as printed documents or photographs, is recorded on paper or film and cannot usually be altered.
Thermal printing using TPHs is a typical hard copy method, known as thermal recording.

3. A Brief History of Hard Copy

The earliest hard copies used paper and ink—a major invention that is still in use today. To meet the need for mass reproduction, printing techniques such as woodblock and movable-type printing were developed, later advancing with Gutenberg’s letterpress printing.
However, producing hard copies with different content on every page remained difficult for a long time. The typewriter was one solution, but it had clear limitations, especially for images and complex scripts.

4. From Analog to Digital

A breakthrough came with the idea of representing text and images as collections of black and white dots. This digital approach enabled new printing technologies, including electrophotography (laser printing), inkjet printing, and thermal printing.
A breakthrough came with the idea of representing text and images as collections of black and white dots. This digital approach enabled new printing technologies, including electrophotography (laser printing), inkjet printing, and thermal printing.
Today, this method is widely used in fax machines, tickets, labels, receipts, and photo stickers.