What is the function of scanner in the microscope?

Answer 1

Document Scanners have a glass plate and a cover. There is also a lamp used to illuminate the document. The scanner moves a mirror, reflecting the light across the document. The light is picked up by a simple CCD camera chip and digitizes the data line by line, like a slow scan TV.

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Scanners have become an important part of the home office over the last few years. Scanner technology is everywhere and used in many ways:

• Flatbed scanners, also called desktop scanners, are the most versatile and commonly used scanners. In fact, this article will focus on the technology as it relates to flatbed scanners.
• Sheet-fed scanners are similar to flatbed scanners except the document is moved and the scan head is immobile. A sheet-fed scanner looks a lot like a small portable printer.
• Handheld scanners use the same basic technology as a flatbed scanner, but rely on the user to move them instead of a motorized belt. This type of scanner typically does not provide good image quality. However, it can be useful for quickly capturing text.
• Drum scanners are used by the publishing industry to capture incredibly detailed images. They use a technology called a photomultiplier tube (PMT). In PMT, the document to be scanned is mounted on a glass cylinder. At the center of the cylinder is a sensor that splits light bounced from the document into three beams. Each beam is sent through a color filter into a photomultiplier tube where the light is changed into an electrical signal.

The basic principle of a scanner is to analyze an image and process it in some way. Image and text capture (optical character recognition or OCR) allow you to save information to a file on your computer. You can then alter or enhance the image, print it out or use it on your web page.

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A scanner is used to scan in printed photographs and other documents so they

can be put into documents or web pages. It uses a light source,

typically a cold cathode lamp to illuminate the scanned imaged. The

light is then reflected off the object and into Charged Coupled Device

(CCD). The Charged Coupled Device collects the information, and through

a series of electronic devices converts the analog signal into a series

of digital signals which can then be read and processed by the internal

electronics of the scanner and subsequently a computer.

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Answer 2

A scanning electron microscope (SEM) is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in araster scan pattern. The electrons interact with the atoms that make up the sample producing signals that contain information about the sample's surfacetopography, composition, and other properties such as electrical conductivity.

The types of signals produced by an SEM include secondary electrons, back-scattered electrons (BSE), characteristic X-rays, light (cathodoluminescence), specimen current and transmitted electrons. Secondary electron detectors are common in all SEMs, but it is rare that a single machine would have detectors for all possible signals. The signals result from interactions of the electron beam with atoms at or near the surface of the sample. In the most common or standard detection mode, secondary electron imaging or SEI, the SEM can produce very high-resolution images of a sample surface, revealing details less than 1 nm in size. Due to the very narrow electron beam, SEM micrographs have a large depth of field yielding a characteristic three-dimensional appearance useful for understanding the surface structure of a sample. This is exemplified by the micrograph of pollen shown to the right. A wide range of magnifications is possible, from about 10 times (about equivalent to that of a powerful hand-lens) to more than 500,000 times, about 250 times the magnification limit of the best light microscopes. Back-scattered electrons (BSE) are beam electrons that are reflected from the sample by elastic scattering. BSE are often used in analytical SEM along with the spectra made from the characteristic X-rays. Because the intensity of the BSE signal is strongly related to the atomic number (Z) of the specimen, BSE images can provide information about the distribution of different elements in the sample. For the same reason, BSE imaging can image colloidal gold immuno-labels of 5 or 10 nm diameter which would otherwise be difficult or impossible to detect in secondary electron images in biological specimens. Characteristic X-rays are emitted when the electron beam removes an inner shell electron from the sample, causing a higher energy electron to fill the shell and release energy. These characteristic X-rays are used to identify the composition and measure the abundance of elements in the sample.

Answer 3

there are so many types of scanners, like X-ray scanners, gamma ray scanner, RF scanners, biological scanners , etc. so please specify the the type of scanner requiring the explanation.

Answer 4

Scans documents such as photographs and pages of text.

Answer 5

To allow a user to dynamically give input, that is, give the program input in a way other than an input file.

Answer 6

Scanning Probe Microscopy is imaging of surfaces that uses a physical probe to scan the item or specimen. It is a branch of microscopy and was founded in 1981.

Answer 7

Scaning documents, photographs and pages of text.