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computerhakk · 10-26-2006, 06:03 AM

2. Different types of scanners.

Flatbed Scanners

There are the most common types of scanners that you will find sitting at a neighbors house, or on sale at an electronic reseller. They are usually the cheapest and most recommended value for a home, or small business use for the fact that it is very easy to operate and maintain. Like the image above, they are usually flat, thus the name goes and works similarly like a photo copier machine. These scanners usually have an opening flap at the top which flips open to reveal the sensor (usually CCD) and a large piece of glass sheet covering or almost about the same size of the scanner itself. Images or documents being scanned work by placing the picture or document face down onto the glass sheet and closing the lid. In the process of scanning the picture, the sensor moves from top to bottom scanning the whole area of that particular media and exporting the results to it's application which you should see on your computer screen.

.
Sheetfed Scanners

Now, a little smaller and a little different, sheefed scanners may look better and seem cheaper right? Well, these type of scanners were usually cheaper than flatbed scanners, however they weren't really reliable. Sheetfed scanners looks and operates similarly like a printer. Instead of having a moving sensor like flatbed scanners, their sensor head is stationed. When scanning, the picture or document is fed through the sensor head, and not the other way around. Good things about these scanners are that you can place several pictures or documents on the bay, and it will scan through all of them without you having to switch or put in the next picture; a very nice feature to have. However, the drawbacks are that this usually results in misfeeds and the possible potential to the media's geting stuck, which isn't really reliable. This could have caused damage to the medias if they were valuable to you. They also were usually limited to 400dpi since they're so small, so the quality isn't all that great.

.
Handheld Scanners

Probably the most uncommonly used of all scanners today. Handheld scanners were the "007" type where you needed it on the go to make a copy of heavily guarded documents. Cool as they sound, they are usually very hard to find in stores today because they really aren't the greatest of all available scanners. Like it's name states, it requires you to use your hand and manually move the scanner throughout the image or document. Like all humans, unless you have precise control and movement to every angle of the paper with your hand, this task isn't an easy thing to master. If you drag it a little too slow, a little too fast, a little off angle, your result will turn out cropped, wrong, or distorted. Not the best of all scanners, however this technology has been implemented into something more useful over the years. It has been used in stores to read off upc codes and scan items nowadays.

.
Card Scanners

You thought they didn't exist? Neither did I, I never knew of them. Anyways, these scanners are actually quite expensive, considering all they do is scan business cards. The idea is basically the same, you stick a business card in, and it spits it out the other end as a computer format you can edit or manipulate. They basically extract all the information from the business cards; such as name, address, contact information, etc. Then this information is stored and made available to you. Models come in both black and white, as well as full color scanners.

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Single Sheet Scanners

Similarly works like the Sheetfed scanners above. However, these scanners only reads a single sheet at a time. They aren't very common anymore and doesn't really produce high quality results. Made back in the earlier days, these types of scanners are probably obsolete now, but there might still be some floating around.

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Drum Scanners

Drum scanners are usually the mother of all scanners. They produce the highest quality result possible and are usually never found at your local electronic reseller. These scanners are usually used in professional printing businesses and sometimes by photographers. Drum scanners work in a very different manner than those previous talked about. The light source is in the middle of the drum, and the photocell's are on the outside. As the drum rotates around the object or media being scanned, it scans every point on a circle around it. The light and photocell's then move a fraction parallel to the axis of the drum for the next line to be scanned and recorded. The curved drum keeps the film to light source distance constant and steady, which in terms avoid problems with reflections and other mess. If you have the money, these scanners costs well in the XX,XXX or even more depending on your like. If you're an average user, this really isn't the one to look into.

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10-26-2006, 06:03 AM	#3 (permalink)
computerhakk VIP Member Join Date: Aug 2005 Location: THOJhakk county Posts: 3,634	Different types of scanners 2. Different types of scanners. Flatbed Scanners There are the most common types of scanners that you will find sitting at a neighbors house, or on sale at an electronic reseller. They are usually the cheapest and most recommended value for a home, or small business use for the fact that it is very easy to operate and maintain. Like the image above, they are usually flat, thus the name goes and works similarly like a photo copier machine. These scanners usually have an opening flap at the top which flips open to reveal the sensor (usually CCD) and a large piece of glass sheet covering or almost about the same size of the scanner itself. Images or documents being scanned work by placing the picture or document face down onto the glass sheet and closing the lid. In the process of scanning the picture, the sensor moves from top to bottom scanning the whole area of that particular media and exporting the results to it's application which you should see on your computer screen. . Sheetfed Scanners Now, a little smaller and a little different, sheefed scanners may look better and seem cheaper right? Well, these type of scanners were usually cheaper than flatbed scanners, however they weren't really reliable. Sheetfed scanners looks and operates similarly like a printer. Instead of having a moving sensor like flatbed scanners, their sensor head is stationed. When scanning, the picture or document is fed through the sensor head, and not the other way around. Good things about these scanners are that you can place several pictures or documents on the bay, and it will scan through all of them without you having to switch or put in the next picture; a very nice feature to have. However, the drawbacks are that this usually results in misfeeds and the possible potential to the media's geting stuck, which isn't really reliable. This could have caused damage to the medias if they were valuable to you. They also were usually limited to 400dpi since they're so small, so the quality isn't all that great. . Handheld Scanners Probably the most uncommonly used of all scanners today. Handheld scanners were the "007" type where you needed it on the go to make a copy of heavily guarded documents. Cool as they sound, they are usually very hard to find in stores today because they really aren't the greatest of all available scanners. Like it's name states, it requires you to use your hand and manually move the scanner throughout the image or document. Like all humans, unless you have precise control and movement to every angle of the paper with your hand, this task isn't an easy thing to master. If you drag it a little too slow, a little too fast, a little off angle, your result will turn out cropped, wrong, or distorted. Not the best of all scanners, however this technology has been implemented into something more useful over the years. It has been used in stores to read off upc codes and scan items nowadays. . Card Scanners You thought they didn't exist? Neither did I, I never knew of them. Anyways, these scanners are actually quite expensive, considering all they do is scan business cards. The idea is basically the same, you stick a business card in, and it spits it out the other end as a computer format you can edit or manipulate. They basically extract all the information from the business cards; such as name, address, contact information, etc. Then this information is stored and made available to you. Models come in both black and white, as well as full color scanners. . Single Sheet Scanners Similarly works like the Sheetfed scanners above. However, these scanners only reads a single sheet at a time. They aren't very common anymore and doesn't really produce high quality results. Made back in the earlier days, these types of scanners are probably obsolete now, but there might still be some floating around. . Drum Scanners Drum scanners are usually the mother of all scanners. They produce the highest quality result possible and are usually never found at your local electronic reseller. These scanners are usually used in professional printing businesses and sometimes by photographers. Drum scanners work in a very different manner than those previous talked about. The light source is in the middle of the drum, and the photocell's are on the outside. As the drum rotates around the object or media being scanned, it scans every point on a circle around it. The light and photocell's then move a fraction parallel to the axis of the drum for the next line to be scanned and recorded. The curved drum keeps the film to light source distance constant and steady, which in terms avoid problems with reflections and other mess. If you have the money, these scanners costs well in the XX,XXX or even more depending on your like. If you're an average user, this really isn't the one to look into. Top of page __________________ "Remember, wrong advice may be worse than no advice at all." ::COMPUTERHAKK::: Last edited by DCIScouts; 10-26-2006 at 08:00 AM.