Active stylus
An active input pen (also digitizer, active stylus ) is an electronic input device that allows users to write directly on the graphic displays of smartphones , tablet PCs or notebooks, for example . The input signals are recorded in the end device and the (writing) movement of the input pen is displayed graphically. The pen can be equipped with buttons and can therefore be used as a replacement for a conventional pointing device ( mouse ). Most devices that can be operated using one inductive input method for use with an active input pen have a second capacitive input method for operation with fingers.
functionality
Active styluses have a directional electromagnetic field . Conductor loops in the display of the device to be operated determine the pointer position by comparing the induced signal strengths. Additional pen information such as pen pressure or pressing a button on the pen is digitized, modulated onto the electromagnetic field and determined together with the position data on the computer of the device to be operated. The pens are powered either by a battery integrated in the pen or directly from the device to be operated via induction (see Fig. 1 - pen components).
Application and functions
Active styluses are commonly used for electronic notes, drawings, document annotations, and precise object selection. When used with handwriting recognition software ( OCR - Optical Character Recognition), the handwritten input of the stylus can be converted directly into digital text and stored for direct editing.
Other possible functions
- Erase - Direct erasure of the input, for example using a button or the back of the pen
- Handball recognition ( palm rejection ) - In the writing position of the pen is an approximation to a few centimeters to the display of the capacitive set screen shortly disabled and thus unwanted entries prevented by the heel of the hand or finger (see Figure 2 -.. Handball recognition)
- Pressure sensor - the contact pressure in the pen can be recognized and transmitted in order to generate a realistic font display (see Fig. 3 - pressure-sensitive display)
- Hovering - If pens are held over displays without direct contact, the hover or mouse-over effect can be imitated.
See also
swell
- ^ Andrew Hughes: Active Pen Input and the Android Input Framework. MS thesis, California Polytech State University, 2011, p. 2.
- ↑ Michael Linenberger: The Importance of an Active Digitizer Pen. October 16, 2013, accessed on February 5, 2015 (English).