Pen Input Devices

These are based on screens that sense the location of a special pen that is connected to the terminal. Following are some of the devices:

• Light pens either detect the monitor’s light or emit light that can be picked up by a specially designed monitor.
• Styluses are pens with electronic point heads which activate pixels on the monitor, usually a LCD display.
• Handwriting recognition software translates alphanumeric to digitised equivalents: normally these needs to be ‘trained’ to recognize an individual’s carefully printed letters, numbers, and symbols. These have been rather primitive, but significant advances have been made recently. They are the primary input device of hand-held PDAs (Personal Digital Assistants) and PIMs (Personal Information Managers) state –of-the- art readers reportedly are very accurate.
• Digitizing tablets  are similar to light pens or styluses except one draws on a tablet rather than the screen.
• Touch screen recognizes human touch and allows selection of menu items displayed on a monitor by touching them.