What are Optical Devices? For a long time, futurists and computer scientists have had the goal enabling computers to “see.” Computers may never see in the same way that humans do, but optical technologies allow computers to use light as a source of input. These tools fall into the category of input optical devices.
The following are the various categories of input optical devices;-
Barcode readers are one of the most widely user input devices. The most common type of barcode reader is the flatbed model, which is commonly found in supermarkets and department stores.Workers for delivery services, such as FedEx also use handheld barcode readers in the field to identify packages. These devices read barcodes, which are patterns of printed bars that appear on product packages. The barcodes identify the product, The bar code reader emits a beam of light—frequently a laser beam—that is reflected by the barcode image. A sensitive detector identifies the Universal Product Code image by recognizing special bars at each end of the image. These special bars square measure completely different, therefore the browser will tell whether or not the Universal Product Code has been read right-side-up so? the wrong way up. After the detector has known the Universal Product Code, it converts the individual bar patterns into numeric digits—-code the pc will perceive.The reader then feeds the information into the pc, like the amount had been written on a keyboard.
IMAGE SCANNERS AND OPTICAL CHARACTER RECOGNITION (OCR)
The barcode reader is a special type of image scanner. Image scanner (also called scanners) convert any printed image into electronic form by shining light onto the image and sensing the intensity of the light’s reflection at every point. Color scanners use filters to separate the components of colour into the primary additive colours (red, green, and blue) at each point. Red, green, and blue are known as primary additive colours because they can be combined to create any other colour. Processes that describe colour in this manner are said to -use RGB colour. The image scanner is beneficial as a result of it interprets written pictures into an electronic format which will be kept in a very computer’s memory. Then you’ll be able to use software to arrange or manipulate the ikon. For example, if you scan a photo, you can use a graphics program such as Adobe Photoshop to increase the contrast or adjust the colours. If you have scanned a text document, you might want to use optical character OCR) are to translate the image into text that you can edit. When a scanner first creates an image from a page, the image is stored in the computer’s memory as a bitmap. A bitmap is a grid of dots each dot represented by one or more bits. The job of OCR software is to translate that array of dots into text that the computer can interpret as letters and numbers. To translate bitmaps into text, the OCR software looks at each character and tries to match the character with its own assumptions about how the letters should look. Because it is difficult to make a computer recognize an unlimited number of typefaces and fonts, OCR software is extremely and complex not always 100 percent reliable. Despite the complexity of the task, OCR software has become quite advanced. Today, many programs can decipher a page of text received by a fax machine. In fact, computers with fax modems can use OCR software to convert faxes directly into text that can be edited with a word processor.
Scanners come in a range of sizes from handheld models to flatbed scanners that sit on a desktop. Handheld scanners are more portable but typically require multiple passes to scan a single page because they are not as wide as letter-size paper. Flatbed scanners offer higher-quality reproduction than do handheld scanners and can scan a page in a single pass. (Multiple scans are sometimes required for colour images, however.) To use a flatbed scanner, you place the printed image on å piece of glass similar to the way you Place a page on a photocopier. In some medium-sized scanners, you feed the sheet to be scanned through the scanner, similar to the way you feed a page through a fax.