The Technical Index, Software and Scanning Principle of Scanner
When we come into contact with the scanner, we will see various technical indicators. The following is a brief introduction to common indicators.
Technical specifications of scanner
1. Scanning accuracy. Resolution, as we often say, is an important parameter to measure the level of a scanner. It reflects the fineness that a scanner can achieve when scanning. Scanning accuracy is usually expressed in DPI (resolution). Similar to the technical specifications of ink-jet printers, the larger the DPI value, the finer the image scanned by the scanner. Scan resolution is divided into two types: optical resolution (real resolution) and interpolation resolution (maximum resolution). The former is in the form of hardware and the latter is in the form of software.
2. Number of color bits. The number of color digits indicates the scanner's ability to recognize colors and the range of colors it can describe. It determines the true degree of color restoration. The larger the number of color digits are, the better and more realistic the scanning effect will be, and the less distortion in the scanning process will be.
3. Gray level. The gray level of the scanner reflects the ability to provide a range of levels from dark to light during scanning, specifically the ability of the scanner to smoothly transition from pure black to pure white. The larger the number of gray scale bits are, the richer the level of scanning results are and the better the effect are.
4. Scan the format. It refers to the range that the scanner can scan, that is, the size of the paper, generally A4, A4+, A3, etc.
5. Compatibility. Almost all scanners can be used for Windows PC.
6. System environment. Scanner work requires drivers, which work in certain system, such as WIN98, WIN2000, WINNT, etc. in addition, some SCSI and USB scanners also have drivers working in FOR MAC (apple) OS.
7. Optional accessories. Usually they refers to the paper feeder (ADF) and through scan adapter (TMA). Not all scanners support additional accessories. As mentioned earlier, some scanners have TMA.
Scanning software
1. Image software. Scanning objects are used for image processing, such as PHOTOSHOP, self-image, scanning masters, and image programs built into WINDOWS.
2. OCR software. Scanned objects are used for word processing, image files are converted into text files, such as thunis OCR, Shangshu OCR, Meng Tian OCR, Wen Tong OCR, etc., as well as TEXTBRIDGE used for English recognition.
3. Vectorization software. For professional scanning of drawings, it is generally necessary to cooperate with engineering scanners which almost all scanners do not have. They need to be purchased separately.
Scanning principle
At present, scanners on the market adopt two completely different manufacturing principles. One is CCD technology, which uses a lens to image on a photosensitive element. The other is CIS contact scanning. CIS technology used to be mainly used in fax machine manufacturing. Its image will be directly recorded by CID photosensitive element after being scanned by LED lamp tube without lens refraction, so the whole body can be made very thin and light. It is more suitable for scanning documents or general plane pictures and texts, but not for scanning three-dimensional articles or transmission documents (Note: transmission documents are documents through which light can pass, such as negatives, slides, etc.).