Sensors

Part1

SCANNERS

Scanners convert optically focused im­ages, such as text, line drawings, or pho­tographs into digital representations that are suitable for processing. When an image is translated into a series of Os and Is, it can then be processed like any other digital data.

The earliest form of scanner used mag­netic-ink character recognition (MICR), a form of character recognition that reads text printed with magnetically charged ink. MICR is still predominantly used by the banking industry for processing checks. All checks contain a series of numbers printed in magnetic ink. MICR makes check processing faster and more accu­rate by capturing data directly from their source without a separate transcribing step.

Another form of scanning uses bar codes. Supermarkets use the Universal Product Code (UPC), which consists of a series of thick and thin bar codes that represent numbers. Marking products this way greatly sim­plifies the information processing asso­ciated with the sale and restocking of products.

Today, bar codes are used in factories and offices. Bar codes are even starting to show up on people. They can be found on patient identification bracelets and on employee badges in hospitals.

Optical character recognition (OCR) is the process of examining char­acters on a printed page and translating them into computer text. OCR was origi­nally designed for input to typesetting machines for the newspaper industry.

In 1976 Raymond Kurzweil intro­duced a reading machine to scan printed documents and, using electronic voice output, read them aloud to the blind or visually impaired. This OCR breakthrough technology could be trained to read the different fonts it encountered. Today there are a wide variety of OCR software interfaces be­tween scanners and personal comput­ers. These programs use various meth­ods of character recognition to convert scanned text into a file, suitable for im­port into a word processor, spreadsheet, or database program. They also interlace with most popular scanners; are able to differentiate automatically among graph­ics, text, and multiple columns; and handle such nuances as regular text versus boldface, italic, or underlined text.

Image recognition. A useful application for scanners is to capture images such as line drawings, illustrations, or photographs, and con­vert them into digital data that can be manipulated, retouched, cropped or resized, and printed.

The resolutionof a scanner is defined as the number of bits per unit of measure (such as inch or centimetre), simply called dots per inch (dpi ). The most common scanner resolution is 300 dots per inch. In the simplest case of scanning an image, the scanner “looks for” black or white. When it “sees” a white point, it translates the white point into a 0; when something other than white is sensed, that is translated into a 1. In this way, the optical image is converted into a digital array of Os and Is.

Compression. Digitized images require a great deal of disk storage. For example, a black-and-white 8.5-inch by 11-inch image, scanned and digitized, would require approximately 1 million bytes of storage. Adding greys or colours requires even more storage space. Compression is a technique for compacting data for more efficient storage. For example, one tech­nique permits blank lines to be replaced by codes that indicate the lines are empty. Today, compression techniques are available that can reduce the amount of storage required for an 8.5-inch by 11-inch image from 1 million to about 100,000 bytes.

4.4 Translate into English the following word-combinations so that you could form compound nouns.

Розпізнавання символів, опрацювання інформації, ідентифікаційний браслет пацієнта, комп’ютерний текст, макетування газети, програма бази даних, роздільна здатність сканера, дискова пам’ять, простір пам’яті, звукова хвиля, коефіцієнт ущільнення.

4.5 Find synonyms.

Convert, image, translate, trace, contain, precise, track, examine, face, picture, accurate, originate, cut, differentiate, transform, link, start, reduce, associate, begin, encounter, distinguish, interpret, check.

4.6 Give English equivalents.

Розпакувати дані, ущільнення даних, відтворювати цифрові дані, метод ущільнення, цифровий відеоформат, цифрове зображення, оптичне розпізнавання символів, розпізнавання зображень, точок на дюйм, сканер штрихового коду, оптичне зображення, збирати дані, відтінки сірого, керувати такими нюансами як, перетворювати сканований текст у файл.

4.7 Complete the sentences with the words from the box. You can use some words more then once.

  voice input device MICR OCR bar code  

1. The use of ______ had led to a significant number of consumer protests because customers suspected secret price manipulation.

2. _________ is the direct reading and conversion of typed or handwritten characters into computer-readable form.

3. ______________ device reads magnetic materials embedded in designated areas on paper documents.

4. ________ device codes information into digital form.

5. ___________________ is used predominantly for check processing in the bank industry.

4.8 Translate into English.

1. Сканери призначені для введення в комп’ютер графічних об’єктів (малюнків, фотографій та ін.).

2. Принцип дії сканера ґрунтується на перетворенні зображення в електричні сигнали.

3. Основною характеристикою сканера є роздільна здатність, яка як і в дисплеях та принтерах визначається кількістю точок на дюйм.

4. Сканери використовуються також і для введення текстової інформації.

Answer the questions.

1. What is a scanner? Give the definition in your own words.

2. What technology is used in scanners?

3. What was the purpose of developing MICR?

4. What are the advantages of MICR application?

5. In what businesses are bar codes used?

6. What is OCR? Explain in your own words.

7. What was OCR originally designed for?

8. What problems are solved with help of OCR today?

9. How is the resolution of a scanner defined?

10. Why is compression considered effective in data storage? Give the examples

Read the text about sensors and give the examples of their application.

Sensors (sometimes called transduc­ers ) are instruments capable of directly encoding a physical event into data. Sen­sors can record changes in temperature, weight, pressure, odour, and light—all of which may be useful as input to a com­puter. For example, at a computer-con­trolled traffic signal, an electronic sensor called a pressure transduceris buried under the street. It senses the flow of traffic and inputs that data to a micropro­cessor that controls the traffic lights.

Today, scientists extend their sensors beyond visible light and capture data at all bands of the electromagnetic spec­trum, including radio, infrared, ultravio­let, and X-ray wavelengths.

The traditional method of using sensors involves connecting a sensing device to a computer system. A new technique combines the computer and the sensor on the same silicon chip because silicon is sensitive to the pressures, tempera­tures, images, sounds, and smells that must be sensed. The combined chips, called smart sensors, are capable of improving the performance of sensor applications because some of the data processing occurs directly in the sensor. Just as the human eye processes much information before it sends signals to the brain, a smart sensor monitors what is being sensed and only sends a signal to a larger computer when necessary.

Дата добавления: 2015-01-03