Flatbed Input DevicesA scanner can be used to input printed images such as photographs or pagesof text directly into the computer. A scanner works by shining a light at the imagebeing scanned and measuring how much light is reflected back using an opticalsensor. The amount of light that is reflected back tells the computer how light ordark the image is at each point.The light and optical sensor reads information about one line of the image at atime. They must be moved down the picture to input the whole image. There aretwo different types of scanner 😕 Flatbed Scanner:o You place the image on top of the scanner. The scanner moves the lightand sensor itself and scans the whole image automatically. Mostflatbed scanners are A4 size.o A flatbed scanner is an optical scanner which makes use of a flatsurface for scanning documents. The scanner is capable of capturing allelements on the document and does not require movement of thedocument.o Flatbed scanners are effective scanners for delicate materials such asvintage photographs, papers and other documents which are fragile.o Unlike other types of scanners, a flatbed scanner only requires the userto lay the document onto the glass and close the lid. Almost all flatbedscanners have an adjustable lid which can be raised to allow thickermaterials to be scanned. o A transparent media adapter, found in some flatbed scanners, can scanfilm and glass negatives. Some flatbed scanners can also haveadditional features such as automatic document feeders and wirelessor Bluetooth connectivity.o Flatbed scanners are known for their high-quality scans. Due to theirability to scan thick objects, flatbed scanners are more versatile thansheet-fed scanners.o Drawbacks of flatbed scanners include being large and bulky. Theyconsume more space than other scanners, and they can also beexpensive.? CCD Scanner:o CCD stands for Charged Coupled Device. In essence, this is the sametype of imaging sensor found inside a legacy digital camera. CCD usesan actual lens to reduce the full image onto the imaging sensor. Thismethod is great for capturing very high resolution details along withwidened color space.o It is because of the fine detail in the CCD type scanner that makes it thescanner of choice for higher resolutions graphics and artisticapplications. Still it is common to see CCD type scanners that are usedfor AEC or technical scans as well.o Another benefit to CCD scanning is a greater depth of field. This ishelpful if you plan to scan many folded sheets. With CCD technology,fold lines can be tweaked a bit through the scanning software so thatthey don’t image as much in the scanned file. CCD scanners also havethe ability to scan ;mounted; or thick originals.? Advantages:? High signal/noise ratio due to florescent lamp light source? Relatively insensitive to focus depth due to cameras withapochromatic lenses.? CIS Scanner:o Contact Imaging Sensor (CIS) is the other type of scanning technology.Instead of using a standard lens to reduce the original image onto thesensor, CIS technology incorporates many fiber optic lenses to transferthe original image information to an array of sensors. CIS technology isless expensive than the traditional CCD models, but there can be sometrade-offs regarding image quality, especially when it comes toscanning aerial photos or maps.o Since there are no cameras to calibrate and the sensors are controlledby software, there is much less maintenance with a CIS -based system.But, because of the poor depth of field of the optics, fold line andwrinkles will image with CIS. Also, there is a reduction of color spaceinformation with CIS. Unless you want to capture mainly primarycolors, CIS could leave you wanting a little more.o Although the physical CIS technology has some limitations, manymanufacturers have overcome this by deploying sophisticated softwarethat compensates for the CIS shortcomings. A great example of this isthe Canon Color Image Logic employed by all Canon/Océ wide formatsystems. Likewise, other manufactures have followed suit and releasetheir own “clean up” software tools. So, most of the time, there can bea good case made for CIS versions, especially when budgets areconstrained.? Handheld scanner:o A handheld scanner, as the name suggests, refers to an electronicdevice that performs the same tasks as that of a flatbed scanner. It isused to scan physical documents into their digital forms that can bestored, edited, transferred and emailed digitally. This device isespecially useful when space is a concern, as flatbed scanners tend totake up a large amount of space.o Handheld scanners are small helpful electronic devices that are widelyused for digitizing printed documents. Although considered lowerquality scanners, they are still very popular because they are small andless expensive than their flatbed counterparts, and they are able toscan items that could not fit in a flatbed scanner due to size orlocation. o Their function includes moving them over the material being capturedwith the aid of a tray to keep it in a straight line.o Experience is required to operate and handle the device since it is veryimportant to keep the scanner straight so that a distortion-free scan ispossible.o Some handheld scanners are now available with added features andfunctionalities such as definitions, translations and reading printed textaloud, as well as storing and sending scanned content to computersand other devices.? Smart Phone Scanner:o As Smart phone have become part of our daily life, we can use them toscan various documents, images, barcodes etc.o There various applications available in google play store or in apple appstore market that are used for scanning documents.o Most popular application that is used is CamScanner in which we canscan either single document or create a whole file containing series ofdocuments by clicking pictures of those hard copy documents.o We can also create a pdf after document has been scanned and alsoshare them via various options.o There are multiple filters available as per user requirements to makedocument more bright and readable.

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