Parts of a Simple Scannerby Steve Johnson
Scanner technology is always advancing. These small electronic devices, capable of producing digital images from a tangible source, are widely used in homes and offices around the world. Through the years, scanners have evolved from the simple drum types to the standard flatbed scanner that is common today. Scanners have simplified and increased the productivity of many people, interlinking the physical and digital worlds. There are several parts to a scanner that allow it to function.
Most scanners incorporate CCDs, or “Charged Coupled Devices,” in their systems. Able to sense light in various forms, CCDs react to the light impulse through photosensitive cells. The CCDs' optical lenses capture the incoming light, which is then sent to a receiver through an analog signal. The benefits of CCDs include improved quality, color and saturation.
Also known as the “Contract Image Sensor,” the CIS functions like the CCD, but it doesn't need the support of optical lenses to manipulate light. Smaller in size than the CCD, this component is commonly found on smaller scanners. The benefits of using CIS include improved sharpness, quality and color.
Scanners cannot function properly without the A/D Convertor. The Analog-to-Digital Converter converts the analog signal from the CCD or CIS to a faster and more compact digital signal. Digital signals can then be transferred as needed through computers and related peripheral devices.
After the images are captured in a scanner, the data must be transferred to a peripheral device, such as a computer, cell phone or camera. This is possible by using ports to connect both devices. The three generic ports that are generally used are the SCSI, EPP, and the USB port. The SSCI — or Small Computer System Interface — uses a card to fully function, while the EPP — or Extended Parallel Port — is directly connected to the parallel port of a computer. The Universal Serial Bus — or USB — is a newer, more functional port that is available on most modern computers.
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