Impact printers - SS1 ICT Lesson Note

Impact printers are a category of printers that create text or images by physically striking an inked ribbon against a printing surface, typically paper. Unlike non-impact printers (such as inkjet and laser printers) that create images without direct contact, impact printers utilize mechanical force to create characters. Despite their declining popularity due to advancements in non-impact printing technologies, impact printers still find niche applications where specific features are required.

Impact printers have some distinct advantages, such as the ability to print on multipart forms, carbon copies, and continuous paper. They are also suitable for certain industrial and rugged environments due to their durability. However, they are generally slower and noisier than non-impact printers. With the advancement of non-impact technologies like inkjet and laser printing, impact printers have lost popularity in many mainstream applications.

Types of impact printers:

1. Dot Matrix Printers: Dot matrix printers are one of the most common types of impact printers. They work by striking a matrix of pins against an inked ribbon, creating dots that form characters and images. Dot matrix printers are known for their versatility, as they can produce multi-part forms and carbon copies. They come in various speeds and print qualities (measured in dots per inch or DPI). While they are not as high in print quality as non-impact printers, they remain useful for tasks that require multiple copies or continuous forms, such as invoices, receipts, and labels.
2. Line Printers: Line printers are designed to print one line at a time. They use a chain, drum, or belt that contains characters or images to be printed. As the printing mechanism rotates, the characters impact the paper to create lines of text. Line printers are known for their high-speed printing capabilities, making them suitable for applications that require fast bulk printing, such as data centers and mainframe environments.
3. Daisy Wheel Printers: Daisy wheel printers use a wheel-like device with raised characters on its spokes. When a character is selected for printing, the wheel rotates, and the selected character impacts the inked ribbon and paper. Daisy wheel printers are capable of producing high-quality output, particularly for text documents, but they are relatively slower compared to other impact printers.
4. Character Printers: Character printers are similar to daisy wheel printers, but they use a print head with a fixed set of characters. They are often used for specialized applications like printing barcodes, checks, and labels.
5. Drum Printers: Drum printers use a cylindrical drum with characters engraved on its surface. The drum rotates, and the characters impact the paper through an inked ribbon, creating the desired print. Drum printers were widely used in the past but have become rare due to their slow speed and noise level.