Image scanner

scannerscannersscanningscannedflatbed scannerimage scanningscanoptical scannerdrum scannerscans
An image scanner—often abbreviated to just scanner, is a device that optically scans images, printed text, handwriting or an object and converts it to a digital image.wikipedia
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Digital image

digital imagesimagesimage
An image scanner—often abbreviated to just scanner, is a device that optically scans images, printed text, handwriting or an object and converts it to a digital image.
Raster images can be created by a variety of input devices and techniques, such as digital cameras, scanners, coordinate-measuring machines, seismographic profiling, airborne radar, and more.

Planetary scanner

Non-contact planetary scanners essentially photograph delicate books and documents.
A planetary scanner (also called an orbital scanner) is a type of image scanner for making scans of rare books and other easily damaged documents.

Film scanner

film scanningscanneddigital scanning
Drum scanners capture image information with photomultiplier tubes (PMT), rather than the charge-coupled device (CCD) arrays found in flatbed scanners and inexpensive film scanners.
A film scanner is a device made for scanning photographic film directly into a computer without the use of any intermediate printmaking.

RGB color model

RGBRGBC-IRred, green, and blue
Color photos were sent as three separated RGB filtered images consecutively, but only for special events due to transmission costs.
Typical RGB input devices are color TV and video cameras, image scanners, and digital cameras.

Contact image sensor

Modern scanners typically use a charge-coupled device (CCD) or a contact image sensor (CIS) as the image sensor, whereas drum scanners, developed earlier and still used for the highest possible image quality, use a photomultiplier tube (PMT) as the image sensor.
Contact image sensors (CIS) are image sensors used in flatbed scanners almost in direct contact with the object to be scanned.

Pixel density

ppipixels per inchHiDPI
However, drum scanners with their superior resolution (up to 24,000 PPI), color gradation, and value structure continued to be used for scanning images to be enlarged, and for museum-quality archiving of photographs and print production of high-quality books and magazine advertisements. Another qualifying parameter for a scanner is its resolution, measured in pixels per inch (ppi), sometimes more accurately referred to as Samples per inch (spi).
Pixels per inch (ppi) and pixels per centimetre (ppcm or pixels/cm) are measurements of the pixel density (resolution) of an electronic image device, such as a computer monitor or television display, or image digitizing device such as a camera or image scanner.

Digital camera

digital camerasdigitalcompact digital camera
Digital cameras can be used for the same purposes as dedicated scanners.
The third method is called scanning because the sensor moves across the focal plane much like the sensor of an image scanner.

Platen

platen press
"A flatbed scanner is usually composed of a glass pane (or platen), under which there is a bright light (often xenon, LED or cold cathode fluorescent) which illuminates the pane, and a moving optical array in CCD scanning. CCD-type scanners typically contain three rows (arrays) of sensors with red, green, and blue filters."
In office copiers and scanners, the platen is a flat glass surface on which operators place papers or books for scanning.

Charge-coupled device

CCDCCD cameraCCDs
Drum scanners capture image information with photomultiplier tubes (PMT), rather than the charge-coupled device (CCD) arrays found in flatbed scanners and inexpensive film scanners. Modern scanners typically use a charge-coupled device (CCD) or a contact image sensor (CIS) as the image sensor, whereas drum scanners, developed earlier and still used for the highest possible image quality, use a photomultiplier tube (PMT) as the image sensor. "A flatbed scanner is usually composed of a glass pane (or platen), under which there is a bright light (often xenon, LED or cold cathode fluorescent) which illuminates the pane, and a moving optical array in CCD scanning. CCD-type scanners typically contain three rows (arrays) of sensors with red, green, and blue filters."
CCDs containing grids of pixels are used in digital cameras, optical scanners, and video cameras as light-sensing devices.

Samples per inch

Another qualifying parameter for a scanner is its resolution, measured in pixels per inch (ppi), sometimes more accurately referred to as Samples per inch (spi).
Samples per inch (SPI) is a measurement of the resolution of an image scanner, in particular the number of individual samples that are taken in the space of one linear inch.

USB

USB 2.0Universal Serial BusMicro USB
Some are portable, powered by batteries and with their own storage, eventually transferring stored scans to a computer over a USB or other interface. This data is then processed with some proprietary algorithm to correct for different exposure conditions, and sent to the computer via the device's input/output interface (usually USB, previous to which was SCSI or bidirectional parallel port in older units).

TWAIN

Standard for image acquisition devices (TWAIN)TWAIN Working Group
For example, Adobe Photoshop supports the TWAIN standard; therefore in theory Photoshop can acquire an image from any scanner that has a TWAIN driver.
TWAIN and TWAIN Direct are application programming interfaces (APIs) and communication protocols that regulate communication between software and digital imaging devices, such as image scanners and digital cameras.

Scanner Access Now Easy

SANESimple ScanSANE libraries
SANE (Scanner Access Now Easy) is a free/open-source API for accessing scanners.
Scanner Access Now Easy (SANE) is an application programming interface (API) that provides standardized access to any raster image scanner hardware (flatbed scanner, handheld scanner, video- and still-cameras, frame grabbers, etc.).

Parallel port

parallelparallel interfaceprinter port
This data is then processed with some proprietary algorithm to correct for different exposure conditions, and sent to the computer via the device's input/output interface (usually USB, previous to which was SCSI or bidirectional parallel port in older units).
The introduction of new devices like scanners and multi-function printers demanded much more performance than either the Bi-Tronics or IBM style backchannels could handle.

Fax

fax machinefacsimilefax machines
Modern scanners are considered the successors of early telephotography and fax input devices.
Stroke speed in facsimile systems is the rate at which a fixed line perpendicular to the direction of scanning is crossed in one direction by a scanning or recording spot.

Computer

computerscomputer systemdigital computer
Image scanners are usually used in conjunction with a computer which controls the scanner and stores scans.

Image and Scanner Interface Specification

Image and Scanner Interface Specification (ISIS)ISIS
ISIS (Image and Scanner Interface Specification) created by Pixel Translations, which still uses SCSI-II for performance reasons, is used by large, departmental-scale, machines.
Image and Scanner Interface Specification (ISIS) is an industry standard interface for image scanning technologies, developed by Pixel Translations in 1990 (which became EMC Corporation's Captiva Software and later acquired by OpenText).

TIFF

Tagged Image File FormatTIF.tiff
Pictures are normally stored in image formats such as uncompressed Bitmap, "non-lossy" (lossless) compressed TIFF and PNG, and "lossy" compressed JPEG.
TIFF is widely supported by scanning, faxing, word processing, optical character recognition, image manipulation, desktop publishing, and page-layout applications.

Édouard Belin

Edouard Belin
Édouard Belin's Belinograph of 1913, scanned using a photocell and transmitted over ordinary phone lines, formed the basis for the AT&T Wirephoto service.

Stepper motor

stepper motorsstepping motorbipolar stepper motor
"Usually, uncut film strips of up to six frames, or four mounted slides, are inserted in a carrier, which is moved by a stepper motor across a lens and CCD sensor inside the scanner. Some models are mainly used for same-size scans. Film scanners vary a great deal in price and quality."
Commercially, stepper motors are used in floppy disk drives, flatbed scanners, computer printers, plotters, slot machines, image scanners, compact disc drives, intelligent lighting, camera lenses, CNC machines and, more recently, in 3D printers.

Windows Image Acquisition

WIASTIStill Image Architecture
WIA (Windows Image Acquisition) is an API provided by Microsoft for use on Microsoft Windows.
Windows Image Acquisition (WIA; sometimes also called Windows Imaging Architecture) is a proprietary Microsoft driver model and application programming interface (API) for Microsoft Windows Me and later Windows operating systems that enables graphics software to communicate with imaging hardware such as scanners, digital cameras, and digital video equipment.

Optical character recognition

OCRcharacter recognitiontext recognition
Typically, in addition to the scanning utility, some type of image-editing application (such as Adobe Photoshop), and optical character recognition (OCR) software are supplied. The resolution used is usually from 150 to 300 dpi, although the hardware may be capable of 600 or higher resolution; this produces images of text good enough to read and for optical character recognition (OCR), without the higher demands on storage space required by higher-resolution images.
This device required the invention of two enabling technologies – the CCD flatbed scanner and the text-to-speech synthesizer.

Dots per inch

dpiDots per centimeterresolution
The resolution used is usually from 150 to 300 dpi, although the hardware may be capable of 600 or higher resolution; this produces images of text good enough to read and for optical character recognition (OCR), without the higher demands on storage space required by higher-resolution images.
Dots per inch (DPI, or dpi ) is a measure of spatial printing, video or image scanner dot density, in particular the number of individual dots that can be placed in a line within the span of 1 inch (2.54 cm).

Barcode

bar codebarcodesbar codes
One common practice is the use of barcode-recognition technology: during preparation, barcode sheets with folder names or index information are inserted into the document files, folders, and document groups.
These barcodes, now commonly referred to as linear or one-dimensional (1D), can be scanned by special optical scanners, called barcode readers.

Book scanning

robotic book scannerbook scannerscanning
A specialized form of document scanning is book scanning.
Book scanning or book digitization (also: magazine scanning or magazine digitization) is the process of converting physical books and magazines into digital media such as images, electronic text, or electronic books (e-books) by using an image scanner.