Scanner

1. Scanner

2. Scanner Introduction: • Scanner is an input device. • It reads the graphical images or line art or text from the source and converts it into digital information and send it to the computer. • Scanner is electronic device that scans data. • Scanners are used to give large volume of data as input to the computer.

3. Specification of scanner: • Scan speed photo color,10*15cm,OCR A4 • Optical resolution4800 dpi*9600 dpi • Min temperature:50 to 95 degree. • Operating humidity range:15-85% • OS:windows, MacOS, windows 7/8/XP/2000. • Power supply: 15W • Port required: hi-speed USB

4. Types of scanner • Flat bed scanners • Sheet fed scanners • Hand held scanners • Drum scanners

5. Sheet fed scanners Flat bed scanners Hand held scanners

6. Operation • Scanner is operates on the principle of reflection . • That is , when a light source falls on an image document , the incident light reflects. • The reflection depends upon the color and size of the images in the document.

7. Structure of Scanner • That is black or white spaces reflect more light than colored or inked letters or images.

8. Cont., • The light from the lamp is made to fall on the document through the glass plate. • The head receives the reflected light from the document with the help of mirrors (m). • The reflected light is filtered with the help of R,G,B filters.

9. Cont., • The filtered light is made to fall on a light sensor having 1024 elements using a mirror and a lens. • The sensor converts the analog signals into digital signals and is given as output. • The scan head is moved over the document with the help of a motor.

10. Scan Resolution • The number of dots or pixels per inch a scanner can resoluve for a document. • In other words resolution relates to the fineness or clarity of the image scanned by the scanner.

11. Different Resolutions • 200 dpi – Dots Per Inch • 400 dpi • 600 dpi and so on. • The more dots per inch a scanner can resolve, the more clarity the resulting image will have.

12. Flatbed scanner • Scan documents, photos, flat object from a PC or laptop. • Works like copy or Xerox machine. • Flatbed is made up of glass pane and moving CCD array and two mirrors. • Most common type of scanner easy to operate, widely used.

13. Flatbed scanner specification • Scanner type: flatbed • Size:280*486*52mm • Weight :1.7kg • Interface:USB1.0 • H/W reslution:1200DPI. • AC voltage:200-240V 50Hz

14. Sheet-fed scanner • Sheet-fed Scanner smaller and portable • Used to scan document and photos • Document is fed into horizontal and vertical slot provided with scanner • Components of scanner sheet-feeder, scanning module & calibration sheet. • Scan single page documents. • Not used to scan thicker objects.

15. Handheld scanner • Smaller in size. • It is scanning device which is moved over the object that needs to be scanned . • To scan the document drag the scanner over document. • Used in barcode scanner. • Image quality is very poor.

16. Drum scanner • Used in publishing industry. • Color drum scanners use three matched photo multiplier tube. • High resolution high quality. • More Expensive. • Drum scanners are slow.

17. Scan modes • Line art • Half toning • Gray scale • True color