Input Units Aj.Drusawin Vongpramate Information Technology, Faculty of Science Buriram Rajabhat University

Input device In computing, an input device is a peripheral (piece of computer hardware equipment) used to provide data and control signals to an information processing system such as a computer or other information appliance. Examples of input devices include keyboards, mice, scanners, digital cameras and joysticks.

Input device Many input devices can be classified according to: Modality of input (e.g. mechanical motion, audio, visual, etc.) the input is discrete (e.g. key presses) or continuous (e.g. a mouse's position, though digitized into a discrete quantity, is fast enough to be considered continuous)

Input device the number of degrees of freedom involved (e.g. two-dimensional traditional mice, or three-dimensional navigators designed for CAD applications)

Input device Pointing devices, which are input devices used to specify a position in space, can further be classified according to: Whether the input is direct or indirect. With direct input, the input space coincides with the display space, i.e. pointing is done in the space where visual feedback or the pointer appears. Touchscreens and light pens involve direct input. Examples involving indirect input include the mouse and trackball.

Input device Whether the positional information is absolute (e.g. on a touch screen) or relative (e.g. with a mouse that can be lifted and repositioned)

Input device Keyboards Pointing devices High-degree of freedom input devices Composite devices Imaging and input devices Audio input devices Punched Card devices

Keyboard A computer keyboard is a hardware device that functions in accordance with the instructions provided by the user. It comprises circuits, switches, and processors that help in transferring keystroke messages to the computer.

Keyboard

Keyboard The keys on the keyboard are as follows:

Keyboard

Keyboard Rubber dome Mechanical

Pointing devices A pointing device is any human interface device that allows a user to input spatial data to a computer. In the case of mice and touchpads, this is usually achieved by detecting movement across a physical surface. Analog devices, such as 3D mice, joysticks, or pointing sticks, function by reporting their angle of deflection. Movements of the pointing device are echoed on the screen by movements of the pointer, creating a simple, intuitive way to navigate a computer's graphical user interface (GUI).

Optical Mice Developed by Agilent Technologies and introduced to the world in late 1999, the optical mouse actually uses a tiny camera to take 1,500 pictures every second. Able to work on almost any surface, the mouse has a small, red light-emitting diode (LED) that bounces light off that surface onto a complementary metal-oxide semiconductor (CMOS) sensor.

High-degree of freedom input devices Some devices allow many continuous degrees of freedom as input. These can be used as pointing devices, but are generally used in ways that don't involve pointing to a location in space, such as the control of a camera angle while in 3D applications. These kinds of devices are typically used in virtual reality systems (CAVEs), where input that registers six degrees of freedom is required

High-degree of freedom input devices

Imaging and input devices Video input devices are used to digitize images or video from the outside world into the computer. The information can be stored in a multitude of formats depending on the user's requirement.

Imaging and input devices Fingerprint scanner Barcode reader 3D scanner Laser rangefinder Eye gaze tracker Digital camera Digital camcorder Portable media player Webcam Microsoft Kinect Sensor Image scanner

Pen Type Readers and Laser Scanners Pen type readers consist of a light source and a photo diode that are placed next to each other in the tip of a pen or wand. To read a barcode, you drag the tip of the pen across all the bars in a steady even motion. The photo diode measures the intensity of the light reflected back from the light source and generates a waveform that is used to measure the widths of the bars and spaces in the barcode.

Pen Type Readers and Laser Scanners Dark bars in the barcode absorb light and white spaces reflect light so that the voltage waveform generated by the photo diode is an exact duplicate of the bar and space pattern in the barcode. This waveform is decoded by the scanner in a manner similar to the way Morse code dots and dashes are decoded.

Pen Type Readers and Laser Scanners CODE 39 CODE 128

Audio input devices Audio input devices are used to capture sound. In some cases, an audio output device can be used as an input device, in order to capture produced sound. Microphones MIDI keyboard or other digital musical instrument

Audio input devices

Audio input devices

Audio input devices

Audio input devices

Audio input devices

Digitizer Digitizer is an input device which converts analog information into digital form. Digitizer can convert a signal from the television or camera into a series of numbers that could be stored in a computer. They can be used by the computer to create a picture of whatever the camera had been pointed at. Digitizer is also known as Tablet or Graphics Tablet because it converts graphics and pictorial data into binary inputs. A graphic tablet as digitizer is used for doing fine works of drawing and image manipulation applications.

Magnetic Ink Card Reader(MICR) MICR input device is generally used in banks because of a large number of cheques to be processed every day. The bank's code number and cheque number are printed on the cheques with a special type of ink that contains particles of magnetic material that are machine readable. This reading process is called Magnetic Ink Character Recognition (MICR). The main advantages of MICR is that it is fast and less error prone.

Magnetic Ink Card Reader(MICR)

Optical Character Reader(OCR) OCR is an input device used to read a printed text. OCR scans text optically character by character, converts them into a machine readable code and stores the text on the system memory.

Optical Mark Reader(OMR) OMR is a special type of optical scanner used to recognize the type of mark made by pen or pencil. It is used where one out of a few alternatives is to be selected and marked. It is specially used for checking the answer sheets of examinations having multiple choice questions.

Question & Answer

Home Work Report on RFID in follow topic (Hand Writing) - Tag - Reader - Frequency - Signaling - Application (more 3 examples)