Telefacsimile, commonly referred to as facsimile transmission or simply fax, is a communication method that allows for the transmission of scanned printed material, both texts, and images, from one location to another via a telephone network. This process is facilitated through the use of fax machines, which scan documents and convert their content into a bitmap for electronic transfer.
How Telefacsimile Works
- Scanning: The fax machine scans the original document, converting it into a binary format - essentially, a series of black and white spots that represent the text and images.
- Transmission: The scanned data is then modulated and transmitted over the telephone network.
- Reception: The receiving fax machine demodulates the electronic data back into the bitmap format.
- Printing: The final step involves printing the received document on paper for the recipient.
Types of Facsimile Transmission
Group 1
The first generation of fax technology, Group 1 faxes, operates at a speed of 6 minutes per page with a resolution of 96 dpi (dots per inch). This technology is now largely obsolete.
Group 2
Group 2 faxes improved on the first generation with a transmission speed of 3 minutes per page and a resolution of 100 dpi. These fax machines provided better quality and faster transmission time.
Group 3
Group 3 facsimile transmission became the standard for a long period, offering further improved transmission speeds (under one minute per page) and higher resolutions of up to 200 dpi, meeting the needs of most business communications.
Group 4
Group 4 faxes were designed for use on digital networks, boasting speeds that are several times faster than Group 3 and offering enhanced quality with higher resolution capabilities.
Historical Context and Evolution
Telefacsimile technology was first conceptualized in the mid-19th century. The invention of the electric telegraph by Samuel Morse was a significant precursor. In 1843, Alexander Bain created the first fax machine, which utilized synchronized pendulums to scan a metallic surface line by line.
The technology saw significant advancements throughout the 20th century, particularly with the development of the modern fax machine by Japanese companies in the 1970s, leading to widespread business use around the world.
Comparisons with Modern Technologies
Email vs. Fax
- Speed: Email transmissions are typically faster and more convenient.
- Quality: Digital copies sent via email maintain high quality without the need for reprinting.
- Security: Fax transmissions are considered more secure in some contexts since they are harder to intercept compared to electronic mail.
Cloud Faxing
Advancements in cloud technology have introduced cloud faxing, where traditional fax machines are replaced or complemented by internet-based solutions, allowing users to send and receive faxes via email or web portals.
Related Terms
- Telephony: The technology of transmitting voice and sound through electrical signals.
- Modem: A device that modulates and demodulates signals for fax and internet communication.
- Bitmap: A mapping from, in this context, a scanned representation of an image to a binary set.
FAQs
What is the difference between a fax machine and a scanner?
Is faxing still used today?
References
- “The History of the Fax Machine” by Jonathan Coopersmith.
- “Fax Modems: How to Select and Use a Fax Modem” by Judd Robbins.
- “Telecommunication Technologies” by John H. Reynolds.
Summary
Telefacsimile, or fax, is a technology that enables the transmission of printed material over telephone networks. Despite the advent of digital communication technologies, faxing remains an essential tool in various sectors requiring secure document transmission. Understanding its functionality, types, and evolution provides insight into its enduring relevance in our technologically advanced society.
