Output Devices

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Audio Output
Audio Output is exactly how it sounds. These are the sounds heard while working on a computer, that incorporates voice, music, and other audio sounds. The most common type of audio output device are speakers. These are used to hear video games, music from iTunes  or YouTube, TV shows on Netflix, Web conferencing, and other types of programs. Most computers have the capability to add additional speakers for better sound quality. The speakers are usually included when the computer is bought. Other speakers vary in a broad span of prices. A subwoofer can be added to amplify the computer’s audio output. Subwoofer’s have low-pitched audio frequencies known as bass and are intended to strengthen the low frequency range of loudspeakers covering higher frequency bands. They can be installed in automobiles and computers.

For portable laptops and mobile devices, the speakers are built into the device. Some desktop computers have speakers permanently installed to the monitor. A unique example of audio output is a treadmill. Some treadmills have the ability to play music from an iPod or MP3 dock, which makes working out more enjoyable. With our rapidly growing and expanding market, recently many car companies have included headphone jacks, dock connections, or USB ports to connect an iPod or mobile device. These connections make it easier for the driver to listen to their own music from their iPod, instead of the radio or CD’s. Headphones can be used as audio outputs as well, instead of using speakers. Using headphones helps users not to disturb others around them (in a library or school).

Display Devices
There are many different characteristics of display devices. These include display colors, monitor styles, resolutions, video compatibilities, and the extra abilities these devices may have. Most devices today have color displays but there are a few which still follow a monochromatic color scheme. The Nook eReader is one of these devices. There is also a difference in the type of monitor in the way it is illuminated. The older style devices such as the large, clunky, heavy tv’s and computer screens are lot with cathode-ray tubes (CRT) and because the tubes take up so much room, the devices needed to be much larger. Today most of our devices are flat-panel displays. These displays use a chemical or gas reaction between two thin clear pieces of material to create their display; this is why they are able to be much thinner and lighter than CRT devices.

Buyer beware, when buying a new device keep in mind that the monitors are measured diagonally. So that new 7″ tablet you are looking at on amazon.com is 7″ diagonally from corner to corner. If you expect the 7″ to be the width, you will be sorely disappointed by the smaller device you receive. Keep in mind also that resolution is important. The more information that can be shown in less space, the clearer the image and higher the resolution will be. Video is input through a video card which holds the GPU inside of it. The video card is used to translate the video information into an image that will appear on the monitor of your device. It uses a fairly large amount of RAM to do so.

There are many ways of connecting video devices to computers, and one of those actually allows the addition of extra monitors to an existing computer allowing for double the screen space. Other interesting features of display devices include the ability to hold a charge (temporarily) on their own and become known as wireless, display images in 2D or 3D format, become much more mobile and even wearable (such as a virtual reality simulator headset), as well as register commands based on touch and motion (e.g. iPhone, iPad, Android phone, and most other “smart” devices today).

Data Projectors
While your computer has many talents and uses, sometimes it might seem as if there’s not enough of it to go around. Let’s say that there’s a hilarious cat video on Youtube that you’d like to share among thirty of your best friends but there’s not enough room for them all to huddle close before your glowing monitor. Instead of splitting the viewing party up in groups, you can use a data projector. A data projector lets you display what’s on your computer monitor onto a wall or projection screen. The image is blown up so all your friends can now laugh in unison as the Youtube cat extends its paws in surprise. Even if you didn’t know the name for it, chances are very high that you’ve encountered a data projector sometime in your life, especially if you attend public school. They can transfer data from computer to projection screen either with a cord or through a wireless connection. For those of you who like to share on the go, there are even portable projectors called pico projectors that can provide a lesser quality but more accessible presentation.

Flat Display Devices
Flat display devices have become increasingly popular over the years because of their slim design and accessibility. Monitors today must be able to provide full color and gray scale, high efficiency and brightness, the ability to display full-motion video, wide viewing angle, and a wide range of operating conditions. Consumers today want these devices to be thin and light weight, be insensitive to magnetic fields, and not produce any x-rays. All of these attributes are not possible with the cathode ray tubes that are generally found in older televisions or monitors.

There are electroluminescent displays, plasma display panels, vacuum fluorescent displays, and field-emission displays all being sold today. The first are used in industries and medical fields because of how durable they are under many temperatures. Plasma displays are usually used in televisions. Vacuum fluorescent displays are used for low information displays like on appliances or small electronics. Liquid-Crystal Displays (LCDS)are the most commonly manufactured displays at this time.

Without even realizing it, we are constantly surrounded by items containing an LCD since they are much thinner and lighter than other displays. Laptop computers, digital clocks, microwave ovens, watches, and many other everyday items all have an LCD. A liquid crystal display works by blocking light as it uses charged liquid crystals that are located between two glass sheets to light up the appropriate pixels using a backlight provided by fluorescent lamps. Conveniently, LCD panels typically already contain those lamps at the rear of the display, hence the term backlight. However, to preserve more energy, today’s new technology has invented light emitting diode displays (LEDs), which are now replacing the fluorescent lamps that were previously used.

LEDs are another flat-panel technology seen in many objects around us like alarm clocks, Christmas lights, and car headlights, etc. An advantage of an LED over an LCD is that they are a lot thinner, have brighter images, color, and quality than an LCD, or even Plasma. Also, since an LED does not require backlighting from fluorescent bulbs, which have a relatively short lifespan, it tends to have a much longer lifespan. As fluorescent lamps burn out more quickly, LEDs are better to use for applications that require turning on and off frequently. Another benefit of LED monitors is the fact that they consume much less power compared to LCDs; LEDs actually consume almost half as much power than an LCD consumes!

A new flat-panel display technology is the interferometric modulator display. This display uses a reflective membrane and a thin-film stack, which sit on a transparent substrate, to reflect external light onto the display. The device uses the interference of light wavelengths to create the different colors necessary for color images. This new display technology is meant to be used for portable devices and new mobile phones. The reason for this is because the display consumes a very little amount of power. By only using external light, the device would not need to continually backlight the display. In fact, the only time the display would need to consume power is when changing the image. This allows for the image to stay open without losing any power for the device, something we all have to deal with everyday on our mobile phones. Another plus for the IMOD display is that the images will stay clear even when in direct sunlight, because it is actually using that sunlight for the image. This is definitely an advantage for anyone who has noticed how hard it is to use a portable device or mobile phone outside when it is sunny. The IMOD display technology is a very energy efficient technology that needs to be utilized in mobile phones and portable devices to help consumers with their issue over battery consumption.

Video Adapters, Interfaces, and Ports
The graphics processing unit (GPU) is the chip devoted to rendering images on a display device. Devices either have a video card or an integrated graphics component built directly into the motherboard or the CPU. The GPU is located in the video card or the graphics component of the computing device. This is what determines the quality of the image that can be shown on a monitor. Video cards will usually contain a fan to cool the card. Video cards will either have a memory chip or they are designed to use a portion of the computer’s regular RAM as video RAM instead. Video cards contain between 256 MB and 2 GB of video RAM. The three most common types of interfaces used to connect a monitor to a computer are VGA (Video Graphics Array), DVI (Digital Visual Interface), and HDMI (High-Definition Multimedia Interface). These are the ports that can be found on a computer to connect it another device, such as a TV screen or a projector. Today, HDMI is used widely amongst major electronic companies like Toshiba, Sony, and Panasonic. This allows for high quality connection and single-cable capability to be used to interconnect devices not matter who manufactured the computer.

Printers today can be divided into two main categories: impact printers and nonimpact printers. Impact printers (known as dot matrix printers) are the traditional printers that actually strike the paper with ink. Their primary uses are for the production of business forms like packing slips and receipts. On the other side are nonimpact printers. These printers do not touch the paper like impact printers, and there are two common types: laser and inkjet. Laser printers use ink powder and inkjet printers use ink, which both create the images with dots (similar to pixels on a monitor). These dots make up the print resolution, which is known as the dpi (dots per inch). The higher the resolution the sharper the image.

General ranges for a dot matrix printer are 60-90 dpi, an inkjet 300-720 dpi, and a laser printer 600-2400 dpi. With that, color printers and black-and-white printers are two standards found in either the home or office setting. Typically for home-use color printers are more common than offices, which will use black-and-white printers due to costs (unless the company needs color for specific materials and products like reports or brochures).

Advantages of laser printers include higher resolutions of the image, faster printing speed, and no smearing. However laser printers are more expensive than inkjet printers, which many people use because they are lower in cost yet still produce high quality images and remain relatively fast in operation. Besides these two types, the advantages of impact printers are their low printing cost per page, their ability to print on multi-part forms and their reliability. However these printers are much louder as well as slower than inkjet and laser printers.

Personal printers and network printers are distinguishable by their connection to either a single computer or a home/office network. Network printers allow multiple computers to print from the same printer, which is why they are a standard in the business setting. Typically personal printers have a rate of 20 to 35 ppm (pages per minute) whereas network printers can print from 30 to 65 ppm.

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Printers can connect via USB, wired or wireless networks, or connections from other devices such as memory cards or cameras. It is not uncommon to see printers that have multiple capabilities like copying, scanning and faxing. These inkjet or laser printers are known as multifunction devices and they can come in color or black-and-white options.

Laser Printers
Why choose laser printer over any other printer? Well, Laser Printers are known to be good for their speed, precision and economy. Since it uses a laser, it can print one page at a time so it’s known to be significantly faster than the ink-jet printers. Although they are more expensive than ink-jet, they seem to be more cost-efficient considering ink is more expensive than toner powder, which is used for laser printers. Laser printers are more reliable with their prints because ink-jet printers tend to leave ink smears. Static electricity is the primary principle in making the printer work, which is an electrical charge built up on an insulated object. It uses objects with opposite static electricity forcing the fields to cling together.

Laser printers can work in either black-and-white or in color. To print on a page, a piece of paper must be first be inserted into the loading tray of the printer. A laser beam electrically charges the drum in the necessary locations that the microprocessor in the computer has decoded based on the image being printed. The ink used is a fine powdered ink known as toner, which is applied while the paper rolls over the drum. The paper finally goes through a fusing unit which permanently binds the toner to the paper.

Ink-jet Printers
Ink jet printers: Why choose Ink-jet printers? Well, ink-jet printers create pictures by spraying ink from the ink cartridges onto the page. Depending on the printer there’s different sized ink droplets, nozzles and electrical charges for more precise printing. They are typically slower than laser printers because of the back and forth motion of the ink tray. Ink-jet printers have grown in popularity and performance while dropping significantly in price. These dots are thinner than a strand of hair and when different colors combined together to create photo-quality images.

Special-Purpose Printers
Though almost every household has some sort of either ink jet printer or laser printer, there are also numerous special purpose printers out there that are made to perform a specific task. Many companies invest in these products to improve time and cost efficiency. Some examples of these printers are photo printers, bar code, label and postage printers, portable and integrated printers, and 3D printers. -Photo printers, as the name quite obviously gives it away, are used for the purpose of printing merely pictures. Often times, people invest in these printers because they produce a better quality picture than just a typical everyday printer would. They also have certain capabilities and apps that one would not just find on any printer.

Businesses are also often found using bar code, label, and postage printers for their products. Every sellable item needs a product label, and having a printer that is designed just for that saves both time and money. They are also useful for the electronic postage capabilities, saving companies time on the mass amount of envelops that they send out on a daily basis. -If you are an on the go businessman or woman, a portable or integrated printer is the way to go. With so much travel and back and forth, it is easy to pull out these commutable printers and print the documents or images you need on the fly. -Finally, possibly the newest and most up and coming printer is the 3D printer. This useful tool can be utilized for printing models and samples. It prints using plastic, and literally produces a finalized 3D prototype of what you want. With technology rapidly improving, more and more products are being designed for the purpose of cost and time efficiency. Depending on what you do on an every day basis, it may be a very wise choice to invest in one of these printers to save you valuable time and money in the long run.  -3D Printers

3D printers use virtual designs created in advanced programs such as CAD (Computer Aided Design) or scanned using a 3D scanner to print out physical models and parts. In order to do this, the software must “slice” the model into thousands of layers that the printer lays down one at at time. There are various kinds of manufacturing methods, such as FDM where material is melted into layers or SLS printing where powdered material is sintered into layers. 3D printing has many applications, especially in design. Even manufacturers now use the printers to create rapid prototypes for research. This saves companies both money and time since changes only need to be made the design file on the computer.

There are different 3d printing methods that were developed to build 3D structures and objects. Some of them are very popular nowadays, others have been dominated by competitors. Most of popular types of 3d printers are:

– Fused deposition modeling (FDM) – 3D printing machines that use FDM Technology build objects layer by layer from the very bottom up by heating and extruding thermoplastic filament.

– Stereolithography (SLA) – SLA 3D printers work with excess of liquid plastic that after some time hardens and forms into solid object.

– Selective Laser Sintering (SLS) – Selective Laser Sintering (SLS) is a technique that uses laser as power source to form solid 3D objects. The main difference between SLS and SLA is that it uses powdered material in the vat instead of liquid resin as stereolithography does.

– Selective laser melting (SLM) – Selective laser melting (SLM) is a technique that also uses 3D CAD data as a source and forms 3D object by means of a high-power laser beam that fuses and melts metallic powders together.

– Electronic Beam Melting (EBM) – The same as SLM, this 3d printing method is a powder bed fusion technique. While SLM uses high-power laser beam as its power source, EBM uses an electron beam instead, which is the main difference between these two methods. The rest of the processes is pretty similar.

– Laminated Object Manufacturing (LOM) – During the LOM process, layers of adhesive-coated paper, plastic or metal laminates are fused together using heat and pressure and then cut to shape with a computer controlled laser or knife.

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