details about Physical interactive devices

1. PHYSICAL INTERACTIVE DEVICES
COMPUTER GRAPHICS

2. TABLETS

3.  Tablet is most common locator device.
 Tablet used in conjunction with CRT display or stand
alone(Digitizers).
 Tablet consist of flat surface and stylus.
 Three principles used to implement tablet
 Orthogonal matrix of individual wire(RAND tablet)
 Using sound waves
 Magnetic principle

4. TOUCH PANELS

5.  A touch panel is a piece of equipment that lets users
interact with a computer by touching the screen directly.
 Light emitters are mounted on two adjacent edges and
light detectors mount on opposite edges(low cost touch
panel)
 A finger interrupting the two orthogonal beam yield an x,y
coordinate pair.
 Resolutions up to 1024 points are available.
 Most useful for gross pointing operation(low resolution).

6. CONTROL DIALS

7. Control dials are simplest valuators, implemented using
sensitive variable resistors or potentiometers.
Accuracy depend on quality of potentiometer.
Control dials used in groups, and are particularly useful for
activating rotation, scaling or zoom functions.

8. JOYSTICK

9.  Joystick is a cursor control device used in computer games and assistive
technology
 Implemented with two valuators
 Third dimension radially incorporated into a joystick(using 3rd valuator)
 Strain in the joystick shaft is measured into two orthogonal direction and
converted into cursor movement.

10. TRACKBALL
A trackball is a pointing device consisting
of a ball held by a socket containing
sensors to detect a rotation of the ball
about two axis

11. MOUSE
Mouse is a pointing device (hand control) that detects two-
dimensional motion relative to a surface.

12. FUNCTION SWITCHES

13. LIGHT PEN
A handheld pen-like photosensitive device held to the
display screen of a computer terminal for passing
information to the computer.

14. SPACE BALL

15. Thank You!
Arun C S
Roll No 13