Skanneri

Skanneri is Finnish for scanner, a device that converts physical documents, photographs, or other media into digital images. Scanners are input devices used in offices, studios, and households to create electronic copies for storage, editing, and sharing. They typically work by projecting light onto the item and measuring the light reflected back with sensors.

Types include flatbed scanners, sheet-fed scanners, and handheld scanners. Flatbeds resemble a copy table and suit delicate or high-resolution work; sheet-fed models process multiple pages quickly; handheld scanners are portable but require manual motion to capture. Key specifications include optical resolution measured in dots per inch (dpi), color depth, and scan speed. Optical resolution describes the true detail captured, while higher settings may rely on interpolation for displayed images.

Most modern scanners use either contact image sensor (CIS) or charge-coupled device (CCD) arrays, along with LEDs as light sources. Color management and dynamic range influence how accurately the scanner reproduces tones and colors. Many scanners include OCR software or export to formats such as PDF, TIFF, JPEG, or PNG, sometimes producing searchable PDFs.

Applications include digitizing documents for archiving, creating digital backups of photographs, scanning receipts, and feeding images into graphic design or desktop publishing workflows. Scanner technology has evolved from drum scanners used in professional studios to affordable consumer devices integrated into multifunction printers.

Historically, high-end drum scanners used photomultiplier tubes and scanned images from rotating drums; later flatbed and sheet-fed designs emerged in the late 20th century, aided by USB, SCSI, and improved image sensors. Modern scanners emphasize speed, color fidelity, and automated document handling, often with built-in software for cropping, deskewing, and text recognition.