How do input devices work

Besides this, it is also used in other areas, medical fields, kiosks, ATMs , room automation, a lot of devices such as cameras, Car GPS, etc. It is an input device to transfer sound into the computer. The analog sound waves are converted into electric signals and are further transformed into digital data and saved in the computer. The microphones are used for adding sound to the presentation, gaming, chatting, voice recognition, etc. The different types of microphones are the dynamic microphone, condenser microphone, ribbon microphone, etc.

A scanner is an input device which reads an image or character from a hard copy document and converts it into a digital file pdf.

Optical character recognition techniques are used in scanners to convert images into digital files. There are different types of scanners available in the market such as flatbed scanner, handheld scanner, sheet-fed scanner, drum scanner, photo scanner, etc. It is a device which can recognize the characters or details on documents that are printed with a special magnetic ink.

This device is mainly used in banks for the only reason that it can process a large number of cheques within minutes with accuracy and is practically tamperproof. It is a technology capable of reading handwritten or printed text on documents and converts them into digitized text or electronic files Pdfs.

OCR copies the details using a scanner and the inbuilt software converts the document into a two-color black and white bitmap version. The reflected light is translated into an analog signal that is decoded by the computer to identify the product details from the database. A webcam is a hardware input device which is either connected to the computer by a USB or inbuilt in laptops and is capable of taking still picture or motion video of the user or an object in front of it.

The photos taken are of the compact digital type which can be uploaded or used over the internet. Other Popular Posts Convenient for application with limited desktop space. It allows easy access o commands. Only items already on screen can be detected. The input document can be text, picture, graphics. Light source below plate moves horizontally from left to right. After scanning one lne, light beam moves up a little and scan next line and process repeates for all lines.

These pictures can easily be transferred to computer and after transferring camera gets ready for the next picture. The no. Web Cameras can directly be connected to the computers where after clicking picture it gets saved in computer directly. It is also useful in video conferencing. Images can be reviewed and edited. Unwanted images can be deleted from the memory.

Photographic Images can be directly digitized without using scanner. Best for 3-D objects. Photo Printing cost is higher than ordinary cameras. The screen is divided into rows and columns.

Each cell of this screen is called Pixel. The number of times the electronic gun redraws the picture on screen is called as the Refresh Rate and it is measured in Hertz Hz.

More the resolution, more clearer will be the picture. A line written on the screen will be visible for up to an hour before it fades away from sight.

It is an alternate method for maintaining the screen image which stores the picture definition inside the CRT instead of refreshing the screen. It draws the picture by knocking out electrons from the storage grid producing a positive charged pattern.

The LCD screen produces images by aligning molecular crystals. These crystals are present in twisted form like a spring and they untwist at varying angles when varying voltages are applied. The front screen is transparent and back screen is reflective. The light gets deviated by these molecules. The larger the number, the higher the resolution. Information produced is permanent.

The time to get the printout is slow, when compared with display devices. Paper is wasted for obtaining the output. Printers are generally noisier than display devices. The paper is usually continuous with holes down each side and perforations so the pages can be easily separated by tearing. Because the pins make an impact against the paper the characters can be printed through several layers of self-carbonating paper to produce duplicate copies.

Vary from 50 to over cps. Suitable uses: Limited to situations where duplicate copies are needed and the quality is not too important. Typical uses might be in warehouses where duplicate copies of orders need to produce quickly and cheaply. Disadvantages The printing quality is low - these printers produce low to medium quality black and white printing and can only print low resolution graphics.

Because of the impact of the pins against the paper, these printers can be quite noisy. Advantages: The purchase cost is low and the running costs are very low.

However, there are other devices that input data into a computer. Although OMR cards and punch cards contain data, they are not considered input devices by themselves. It is the readers that interpret the cards that are considered an input device. Every computer comes with a keyboard and a mouse touchpad with laptop , which are considered input devices. As far as other input devices, it depends on what was included with your computer and what's connected to the computer.

The best method of determining all of the input devices your computer has is to go through the list above. What an input device sends inputs to a computer depends on the device. For example, OCR software can convert scanned in text into a computer readable form. A 3D scanner is an input device that creates a 3D model of the object scanned.

Test your knowledge of input devices with our quick quiz. Developed long before touchscreens became affordable, interactive whiteboards combine a large touch sensitive board with a projection screen.

A touchscreen is an electronic visual display that also incorporates an input device that responds to touch. This allows users to select options from a screen by simply touching them.

A barcode is a machine readable code represented by an image consisting of black and white lines. The lines in a barcode relate to numbers 0 to 9. Black and white surfaces reflect light differently, with black bars reflecting less light than white bars. Sensors are used to capture the amount of light reflected and the different reflections are converted to binary values.