Graphic Pen Tablet
A Graphics Tablet (also known as a digitizer, digital graphic tablet, pen tablet, drawing tablet, or digital art board) is a computer input device that enables a user to hand-draw images, animations and graphics, with a special pen-like stylus, similar to the way a person draws images with a pencil and paper. These tablets may also be used to capture data or handwritten signatures. It can also be used to trace an image from a piece of paper that is taped.
The device consists of a rough surface upon which the user may "draw" or trace an image using the attached stylus, a pen-like drawing apparatus. The image is shown on the computer monitor, though some graphic tablets now also incorporate an LCD screen as IPS, for more realistic or natural experience and usability.
Typically tablets are characterized by size of the device, drawing area, its resolution size («active area»), pressure sensitivity (level of varying the size of strokes with pressure), number of buttons and types and number of interfaces: Bluetooth, USB; etc. The actual drawing accuracy is restricted to pen's nib size.
There have been many attempts to categorize the technologies that have been used for graphic tablets:
- Passive Tablets – Passive tablets make use of electromagnetic induction technology, where the horizontal and vertical wires of the tablet operate as both transmitting and receiving coils.
- Active Tablets – Active tablets differ in that the stylus used contains self-powered electronics that generate and transmit a signal to the tablet. These styluses rely on an internal battery rather than the tablet for their power, resulting in a bulkier stylus.
- Optical Tablets – Optical tablets operate by a very small digital camera in the stylus and then doing pattern matching on the image of the paper.
- Acoustic Tablets – Early models were described as spark tablets—a small sound generator was mounted in the stylus, and the acoustic signal picked up by two microphones placed near the writing surface. Some modern designs are able to read positions in three dimensions.
- Capacitive Tablets – A capacitive graphics tablet is an electronic drawing tablet that uses capacitive touch-sensing technology to operate. When you touch the surface with a bare finger or capacitive stylus, it creates a change in capacitive, which the tablet uses to determine the location of touch.