Thermal fax machines work by implementing heat to print a fax.

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Despite the fact that we're standing on the cusp of a "paperless age," fax machines still are used to send important documents quickly when an email doesn't cut it. Business owners would argue that owning a reliable fax machine is essential. But most of us don't really know how these machines work or which type we should purchase. In this article, we'll take a look at the inner workings of the thermal fax machine, an old-fashioned, but useful and inexpensive business tool.

Thermal fax machines send and receive information the same way other fax machines do. The scanning mechanism uses photo sensors to scan the document and read thousands of tiny dot areas to determine whether each dot area is black or white. The machine then encodes and compresses this information and sends it over a telephone line to another fax machine. See "How Fax Machines Work" to get a closer look at this process.

What sets thermal fax machines apart from other fax machines is the method they use to print out that information accurately on the receiving end and make it readable on a piece of paper. Thermal fax machines don't even need an ink cartridge to do this. Instead, they utilize the powers of thermal technology to print a fax, or facsimile, of the original document.

Two kinds of thermal fax machines can do this, and they both use fairly simple methods. One kind stores the necessary "ink" in the paper itself, while the other kind extracts it through a process of melting down special ribbon against the paper.

How is heat used to create a print-out? Read the next few pages to learn just how these machines work their thermal magic.