The humble portable scanner has become a massively important piece of equipment and is most useful for someone working from home or on the move. A portable scanner will analyze an image before processing it. As a result, you will be able to save the scanned document onto your computer. Once there, you have the ability to change the image before printing it out. Flatbed scanners are the most commonly used scanner with handheld portable scanners also increasing in terms of sales. The main difference between a portable scanner and a flatbed scanner is the fact that you need to move the scan head across the image to be scanned whereas a flatbed model has a motorized belt.
The scanner uses CCD (Charge-Coupled Device) technology in order to capture images. CCD works because extremely small diodes (known as photosites) convert light into electrical charge. These diodes are very sensitive to light. The more light that hits one of these diodes, the stronger the electrical charge created. Once you place the document on your portable scanner, it goes through mirrors, lenses and filters on its way to the CCD technology.
When you press the scan button, the image is illuminated below the scanner by a light emitting diode (LED). There is an angled, inverted mirror that is located above the window of the scanner which will reflect the image onto a lens which can be found on the rear of the scanner. This lens will focus one line of the image onto the aforementioned CCD. The light from the scanner will shine onto a host of light detector rows on the CCD which will register the level of light. This is equated to a level of voltage that leads to grey, black or white.
The Scanning Process
The CCD light voltage which has been generated is received by analog chips for gamma correction. The result of this process is an enhancement of the black tones into an image which is much easier for a person to discern. The image line now goes to the analog-digital converter which gives each pixel 8 bits. This equals 256 different shades of grey. The disk will start to turn and the photomicrosensor, which is located at the disk’s other side, will pick up on the light which shines through the little gap created in the slits. This light hits the sensor which in turn helps send a signal to the analog-digital converter. This signal causes the converter to send the created line of bit to the computer. When this process is completed, the converter removes the data and goes on to the next line where the process is repeated until the full document is scanned.
Having a portable scanner in the home is a great way to not only scan documents, but also to scan business cards, photos and credit cards amongst other things. It is a piece of equipment that makes life so much easier, especially if you are running a business from home. It can also be used on the move which is its main selling point. If you’re traveling, you can bring a portable scanner along with your laptop and connect it via a USB cable. This will ensure that you’re never caught short when a client is in dire need of a document.
How Portable Scanners Work
By cosmos Oct 6, 2011 Edited Jul 25, 2016 0 0