What is Scanner: Definition and 31 Discussions

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. Commonly used in offices are variations of the desktop flatbed scanner where the document is placed on a glass window for scanning. Hand-held scanners, where the device is moved by hand, have evolved from text scanning "wands" to 3D scanners used for industrial design, reverse engineering, test and measurement, orthotics, gaming and other applications. Mechanically driven scanners that move the document are typically used for large-format documents, where a flatbed design would be impractical.
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 rotary scanner, used for high-speed document scanning, is a type of drum scanner that uses a CCD array instead of a photomultiplier. Non-contact planetary scanners essentially photograph delicate books and documents. All these scanners produce two-dimensional images of subjects that are usually flat, but sometimes solid; 3D scanners produce information on the three-dimensional structure of solid objects.
Digital cameras can be used for the same purposes as dedicated scanners. When compared to a true scanner, a camera image is subject to a degree of distortion, reflections, shadows, low contrast, and blur due to camera shake (reduced in cameras with image stabilization). Resolution is sufficient for less demanding applications. Digital cameras offer advantages of speed, portability and non-contact digitizing of thick documents without damaging the book spine. In 2010 scanning technologies were combining 3D scanners with digital cameras to create full-color, photo-realistic 3D models of objects.In the biomedical research area, detection devices for DNA microarrays are called scanners as well. These scanners are high-resolution systems (up to 1 µm/ pixel), similar to microscopes. The detection is done via CCD or a photomultiplier tubes.

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  1. Nikkie

    Electronics Stationary 3d scanner using a standard camera

    I know there are some stationary 3d scanners like this, but they are really expensive. When I saw, well an addition to handheld 3d scanner - a robotic hand, I came up with an Idea that same can be done with a simple camera, and photogrammetry. Found a nice article about photogrammetry on the...
  2. S

    B Glass in flatbed scanner transparent to UV-C (~254nm)?

    Hello, I am making a DIY UV-C germicidal box as part of my defense-in-depth strategy for protecting my household but I am having trouble determining whether a particular plate of glass that I have will be transparent to UV in the 250-280nm range. The glass in question is from a flatbed scanner...
  3. J

    Comp Sci Twitter API finding the most common word in a tweet

    So in the class TJTwitter, I have the following defined: private Twitter twitter; private PrintStream consolePrint; private List<Status> statuses; private List<String> terms; private String popularWord; private int frequencyMax; and in the same class, I have a few methods that are meant to...
  4. theycallmevirgo

    Suggested starting points for 3d scanner design

    My school recently got an industrial robot arm with a precision turntable. I was thinking how to use this with some cameras/lasers to make a 3d scanner. Where would you folks recommend I start looking?
  5. berkeman

    Can a 2-D barcode scanner be used with OCR applications?

    I have a need for a hand-held scanner to be able to read a MAC ID displayed on a monitor. The MAC IDs are sent to my application via a network, and I need to automatically read each MAC ID into a different application. For various reasons (Linux versus Windows applications running on different...
  6. Myles Cummings

    B How much should it cost to build an MRI Scanner?

    I recently had an MRI scan, and while I was inside I began thinking about how the thing actually worked, and what it would cost to build. The hospital staff told me that the cost was several million dollars, and subsequent research seems to confirm that the 'average' MRI scanner cost between 3-5...
  7. Wrichik Basu

    Java Preferring Scanner to BufferedReader for taking input

    I have seen that in many cases, teachers and authors prefer Scanner to BufferedReader for taking input from the user through keyboard. I have found two reasons for this: 1. Scanner class manages exceptions implicitly, while for BufferedReader, exceptions have to be handled either by try..catch...
  8. K

    I Experiment Ideas using an MRI scanner?

    So I've stumbled upon a really cool opportunity this summer, where I basically have a hospital which has agreed to let me do an experiment using their 3T MRI machine. I'm a physics undergrad and I want to do a physics experiment using the MRI, but I have absolutely no idea what to do. I've tried...
  9. sunbeam667

    Terahertz scanner: does it work?

    Hello everyone! Maybe someone good at this topic or met this problem before, because I was really confused reading about this << Link deleted by Mentors as Spam >> Can someone tell me: does it actually work? And how terahertz radiation can influence on the human body, considering that THz waves...
  10. lukasleopold

    Estimating sound pressure (in an MRI scanner)

    Hello, excuse me if these happen to be basic questions, but I'm a psychologist/neuroscientist in training without any particular experience in physics, and I am just confronted with a very specific problem. I need to measure the sound pressure experienced inside of an MRI scanner...
  11. B

    Signal to noise ratio in a CT scanner

    Homework Statement If the relative noise (noise divided by signal) in a region of a CT slice is measured to be N what would be the value if the tube current was halved, the pitch increased from 0.9 to 1.2, the rotation time increased from 0.75s to 1s and the slice width increased from 1mm to...
  12. nuclearhead

    Idea for an internal scanner using natural radioactivity

    Here is an idea I had for a way to deduce the internal structure of an organic object using it's natural radioactivity. The set-up is an array of gamma ray detectors located circularly around the object. By detecting both the position and direction of the gamma rays (obviously impossible to get...
  13. T

    3D Scanner using static electric fields

    Greetings PFers, Can someone help explain to me the difficulties of designing a device which utilizes static electric fields to map an objects’ internals and externals? My understanding is that as a electric field propagates through matter, it encounters absorption. I envision a device...
  14. S

    Piezoelectric effect- tube scanner

    Hi, i have been working on this problem for a while. i just need some guidance. the question is: design a ztube scanner suitable for displacing ±1 micron displacement at 200V. i am using this equation: ΔL=([d]_{}[/31]×V×L)/t ΔL=(d31 ×L×V)/t ΔL=change in length = 1micron...
  15. M

    Possible Brain Scanner Invention?

    Hello, I am not sure where I should be posting this, so if this is the wrong section, can a moderator please move it? Right. I have become rather fascinated with the worlds technology and physics. Now, if you've ever heard of lucid dreaming and I'm sure many of you have. I lucid dream...
  16. H

    Sun Orbital Scanner: Magnifying Star Systems to Detect Planets

    If we had an array of detectors in an orbit around the sun could we magnify the image of distant star systems. Would this help to detect planets using this magnification?
  17. D

    What is the equation for torque in an MRI scanner?

    There are (at least) two issues regarding the presence of ferromagnetic materials around an MRI scanner (of strength e.g. 3 Tesla). (i) that something (e.g. scissors in a health worker's pocket) becomes a projectile, and (ii) that an implant may experience a twisting force (e.g. ferromagnetic...
  18. C

    Can you make RFID scanner to detect any 3rd party tags despite countermeasures?

    suppose Team Red wants to make RFID tags that only their own "authorized" scanners can pick up, such as for tagging merchandise in Walmart. Meanwhile Team Blue wants to be able to find any Team Red tags on items or prove that they are not there. They don't need to extract any info from the tags...
  19. S

    Analyzing STM Scans for Tunneling Current Changes

    Homework Statement Suppose that an STM scans a surface at a distance of a=1.000nm. Take the height of the potential barrier to be U°-E=2.00 eV. If the STM tip movies away from the surface by 2.00%, estimate the percentage change in the tunneling current. Homework Equations The...
  20. M

    Fingerprint Scanner Homework: Finding Points to Identify Fingerprints

    Homework Statement I am currently working on making a fingerprint scanner, by using frustrated total internal reflection of an infrared LED, with an image taken with a webcam. This setup is fully working and gives a reasonably sharp image.. however now i need to try to make a small program...
  21. N

    Are the Airport Scanners Emitting Dangerous Levels of Radiation?

    Anyone know the radiation levels that are output by the full body airport scanners? I am not looking for a relative amount, but a quantitive amount. If you do not know, please don't answer.
  22. J

    Comp Sci Java Scanner Issues: Troubleshooting Read Input from Keyboard

    I am having some trouble with the Java Scanner to read input from the keyboard. I am trying to keep my input cleaned up and secure, so I am checking for the right type and value, and clearing the input buffer if it isn't. I also restart the prompt loop if it isn't right, so they can try again...
  23. J

    [vb.net 3.5]Console application for Falcon Barcode Scanner

    Anyone familiar with BarCode scanners? I have four of them I want use with my app. Can a console (custom) app be used to load/save scanned data?
  24. F

    Using Pointer & Scanner to Read Integer Strings

    What I want to do is pass in a string to read_integer (a function which will parse the string character by character, convert the characters into ints (c - '0'), store it into a struct, and return a pointer to that struct. The string is guaranteed not to be over 200 digits.). I'm not sure how to...
  25. M

    Java Using Scanner in Java to await user hitting return key

    Hi all, I've been trying to figure out how I can use the Scanner class in Java to pause my program and wait for the user to hit the return key. What I have now looks like this: Scanner kbd = new Scanner(System.in); kbd.next(); ... The thing is, the rest of my program won't run unless there...
  26. D

    What is a Scanner Reading Software that Converts Pictures to Text?

    I don't know how to describe this properly in a few words, hence the awkward thread title. I used to own this particular program which is able to decipher words in picture files to actual text which can then be copied to MS word or other word processors. It doesn't require a scanner but it...
  27. T

    Comp Sci Java Scanner Help for 8 Teams Output

    Hi, I'm trying to create this output: Input team 1's name: Team 1 Input team 1's ranking: 90.4 etc. For 8 teams. This is what I have: import java.util.Scanner; public class Tournament { public static void main(String args[]) { System.out.println("Input team 1's name:")...
  28. C

    Java Java Programming: Fixing Scanner Issues

    Java's "Scanner" Hello, I own a Macintosh and was trying to write a simple Java program for one of my classes. However, I quickly discovered that it appeared that the Mac does not have the Scanner ability. I get an error on the "import java.util.Scanner" line saying "cannot find symbol...
  29. L

    Can Scanning My Hand with Light Harm It?

    if i put my hand on the scanner and scan my hand, do u think the strong light will harm my hand? because i really want to scan my hand, but i don't know whether it is harmful.
  30. wolram

    Program that drives my scanner had bits missing

    i had a problem earlier that russ,zantra and greg helped me out of, basicaly the program that drives my scanner had bits missing, as i NEVER load anything on my computer, apart from the os or download from the net, apart from saving certain items to MY DOCUMENTS, how can this happen? my...
  31. T

    Understanding Scanner Functionality

    How does a scanner work?