Scanners, flash Scanners, flash drives, digital drives, digital camerascameras

ScannerScannerss

Types: handheld, flatbed, film/slide, drum(industrial)

Components: Charge-coupled device (CCD) array, mirrors, scan head, glass plate, lamp, lens, cover, filters, stepper motor, stabilizer bar, belt, power supply, interface port(s), control circuitry

How it works: lamp lights document, scan head moves across the document, mirrors reflect the image onto a lens, and the lens focuses the

image through a filter on the CCD array.The marketplace

Quality measurement: CCD vs. CIS (Contact Image Sensor) Resolution: hardware sampling (1,200-4,800 dpi),

and software (interpolation): 9,600- unlimited. Sharpness: depends on the quality of the

lens and the brightness of the lamp. Depth: 36-bit, up to 48-bit color, but output

is 24-bit

Interfaces: USB, SCSI, FireWire, parallel Software: Twain and WIA (conflicts in XP)

Scanner FAQ

ScannerScannerss

Use XnView to edit

Flash RAM and drivesFlash RAM and drivesFlash RAM basics a solid state storage: a type of SRAM, EEPROM

chip nonvolatile and does not require constant

power to retain information, unlike DRAM. How it works: cells values are defined by rows

and columns grid using tunneling.

Devices that use flash RAM BIOS chip memory cards: PDAs, cameras, MP3 players, etc smart cards: future of smart cards? flash USB drives: why not replace hard-drives?

Flash USB drivesFlash USB drivesFlash USB drive basics NAND flash memory (cells arranged serially)

integrated with a USB interface , up to 8 GB of storage

components: USB connector, USB mass storage controller (CPU and memory), flash memory chip, crystal oscillator (clock), LED

More The USB Flash drive alliance Making the USB flash drive bootable Portable applications for USB flash drives

Digital camerasDigital camerasDigital camera basics based on CCD (we saw it in scanners):

sample the original light that bounces off the subject, converting light patterns into pixel values

resolution: the number of unique cells in the CCD, measured in megapixels

capturing color: color filter array over each photosite

exposure, focus and zoom storage media: flash RAM and file sizes interfaces: USB or FireWire, also storage

media readers (floppy, USB) Image management: XP, XnView

Digital camcordersDigital camcorders

The basics analog camcorders: CCD, lens and motors to handle

zoom, focus and aperture, VCR shrunk down to fit in it.

digital camcorders: captures a frame of video from the CCD and (using an analog-to-digital converter) records the signals as bytes in a tape, DVD or hard-drive.

digital formats: MiniDV, Digital8, DVD, memory cards

The marketplace digital camcorders: 2002, 2004, 2005 digital cameras: big cameras for beginners