Study On Computer Input And Output Devices

The history of ergonomics is start from Greece. The meaning of ergonomics come from Greek words ergon [work] and nomos [natural laws] and first entered the modern lexicon when Wojciech Jastrzębowski used the word in his 1857 article Rys ergonomji czyli nauki o pracy, opartej na prawdach poczerpniętych z Nauki Przyrody (The Outline of Ergonomics, i.e. Science of Work, Based on the Truths Taken from the Natural Science).

Ergonomics is the science of fitting workplace conditions and job demands to the capabilities of the working population. It can effective and successful to give user adaptation and guarantee for high productivity ,and avoid the illness or injury risk. Even more ,it increase the satisfaction of labor force.

To assess the Ergonomics devices can suitable for user it depend on the devices size, shape, and how appropriate it is for the task. Besides that, Ergonomics draws on many disciplines in its study of humans and their environments, including anthropometry, biomechanics, mechanical engineering, industrial engineering, industrial design, kinesiology, physiology and psychology.

Ergonomics also include 3 types.

Physical ergonomics: Human anatomy, anthropometry, physiology and biomechanical characteristics as they relate to physical activity. And how the physical environment around you may affect your performance or understanding of the environment, the impact on people in these areas, especially the harmful effects. Then you can design one that will not damage their environment, they may even enjoy the experience

Cognitive ergonomics: concern about mental process like perception, memory, reasoning and motor response , Because they affect interactions among humans and system interaction of other factors.

Organizational ergonomics: is trying to organise people and the work to best effect.

3.0 Input devices

Input devices is any peripheral equipment (computer hardware chip), data and control signals used to provide an information processing system (such as computer).

3.1 Mouse

A mouse is a pointing device that functions by detecting two-dimensional movement

relative to its supporting surface. Let user to control their personal computer.

The first mouse is design by Engelbart in 1963,with the assistance of his colleague Bill English.

The first mouse is heavy and big, used two gear-wheels perpendicular to each other: the rotation of each wheel translated into motion along one axis.

Before, the ergonomic mouse designed have a old type of mouse named “mechanical mice”. It use a single ball that could rotate in any direction. But due to the ball touching the other surface ,to make the mouse work, the dust of the surface will stick with ball. After the ergonomic mouse is design, the disadvantage of the mechanical mice will be improve.

Ergonomic have many type, such as the mouse using wireless or Bluetooth connect to computer named “wireless mouse”. So ,this kind of mouse is portable as long as it use inside the range with computer.

Besides that, there is a 3D mouse. The method of using this mouse by push, pull, twist or tilt to simultaneously pan, zoom and rotate. So ,this kind of mouse is difference from other mouse.

Other than that, there is a mouse is design for gamming ,because this kind of mouse has shortcut key. So, user can use the shortcut key to perform the action inside computer faster.

Lastly, design of the sharp for mouse also important in ergonomic mouse. This is because,

The sharp of mouse can let user shoulder or the muscle of hand reduce tension and comfortable to grip it. So ,The mouse can reduce the working disease like injury the muscle.

3.2 Keyboard

Keyboard, typewriter keyboard, which uses the button or key arrangement, as a lever mechanical or electronic switch. After punch cards, paper tape through fax-type keyboard, interactive computer into the main input device.

There is many type of keyboard can use in our life. They are Chorded keyboard ,Software keyboard ,Foldable keyboard ,Laser keyboard ,Optical keyboard technology.

Chorded keyboard: Although other associated with a keyboard and keyboard chorded key combination and correlation of each key action, action. Because it use many combination available so can effectively produce more action on a board with fewer keys.

Software keyboard: It is a software but display on the screen of the devices. Nowdays ,software keyboard is popular and normally can found inside of the touchscreen phone.

Foldable keyboard: Folding (also known as flexible) is made of soft plastic or silicone keyboard can be rolled up or folded travel itself. [2] In use, the keyboard can meet these uneven surfaces, and more resistant to the liquid than the standard keyboard. These can also be connected to portable devices and smart phones. Some models can be completely immersed in water, so that they received in hospitals and laboratories, as they can be disinfected.

Laser keyboard: Projection keyboard projects the image of a key, usually with a laser, to a flat surface. The device then use the camera or infrared sensor to “monitor”, the user’s finger moves, and will be counted as being pressed, the “see” the user’s finger to touch the projected image of the key. Projection keyboard can simulate from a very small projector full-size keyboard. Because “the key is only projected images, they can not be considered when pressed. Projected increase in keyboard users often experience discomfort due to lack of their own fingers” to “when typing. Flat, reflective surfaces do not need to be projected onto the key . most of the projection makes use of the keyboard and PDA, because of its small size.

Optical keyboard: This kind of keyboard that can help user neck and shoulders less tension when using it. Or the keyboard can move able ,connect by Bluetooth or wireless to computer.

3.3 Touchpad

Touchpad pointing device is a special surface can translate the user’s finger motion and position in the relative position on the screen composition. They are a common feature of the notebook can also be used as a computer mouse in the desktop space is limited alternatives. Touchpad vary in size , but few make over forty 40 square centimeters (6.3 x 6.3 cm or about 6 inch²). Touchpad is probably the most common form of tactile sensors.

Touchpad is mainly used in a separate laptop, do not need the machine near the surface. Touch pad near the keyboard, only a very short finger movements is the need to move the cursor on the display screen, while beneficial, it also makes it possible for the user’s thumb moves the mouse cursor when typing accident. Feature is the touchpad on the desktop computer keyboard with the existing built-in touchpad.

Touchpad can help reduce the tension of finger ,hand and shoulder. Using it also comfortable.

It also consist of mouse function like right and left click ,scroll down or up.

4.0 Output devices

Output device is a computer hardware device for communication with any part of the results of data processing information processing system (such as a computer) to the outside world.

4.1 Monitor

Monitor is a computer display and related parts packaged in a physical unit that is separate from other parts of the computer.

Monitor concern physical ergonomics side is about the height of monitor ,distance

Between eye to monitor ,the monitor effect to body and the monitor setting.

Normal monitor easy make our neck ,upper back and eye feel tired easily.

Ergonomics monitor can help our neck ,upper back and eye reduce the tiredness.

this is because ergonomics monitor can change the height ,setting and distance.

Monitor distance should located directly in front of the user where the positioned to view monitor. The distance between eye to the monitor screen at less need around 17-20inch away.

But if using a small monitor can located it closed a bit. If using a big monitor need to locate little farther away.

Monitor setting can change the monitor resolution ,contrast and brightness. As the result,

The setting can help user to view the monitor more clearly ,it also help user to reduce eye tiredness.

Monitor height is important ,because it can prevent our neck and upper back muscle reduce tension. To determine the correct monitor height ,first sit infront of monitor and then close eyes

and make the position of head and body in a neutral and comfortable position ,spine need be straight .After that open eye and note the point where your vision ,that is the correct monitor height.

Monitor concern organizational ergonomics side is improve the monitor light weight ,reduce electric comsumption and the speed of display.

CRT(cathode ray tube) is the 1st type of monitor. It has high dynamic range ,good colour ,wide gamut and low black level. It can also display natively in any resolution and refresh rate. However,

CRT weight is too heavy and big size so now has less people using it.

LCD(liquid crystals display) is come after the CRT. LCD is compact ,light weight ,low electric comsumption and no geometric. But ,LCD has a limited viewing angle and slow response times. So ,LCD is suitable for 1 person to view the monitor.

Plasma is the lastest design for display. It mostly overcome the problem from CRT and LCD like high speed response ,viewing angle. Plasma same as LCD as compact and light weight ,so it easy to carry. However ,plasma is still facing the input lag problem.

4.2 Earphone

Earphones are a pair of small speakers, or less see a speaker, has held close to the user’s ears, and connection methods, such as audio amplifier, radio or CD player to a method of source

Type of earphone

The special needs of the listener determines the choice of headphones. Should be noted that the portability of smaller, lighter headset, but it may mean a compromise in Fidelity. Hi-fi headphones as part of a family does not have the same design constraints can be larger and heavier. In general, the shape of the headset can be divided into four different categories: circumaural, supra-aural, earbud, and in-ear.

Circumaural: Circumaural headphones (sometimes called full-size headphones) are round or oval-shaped ear pads, which should include the ears. Since these headphones completely surrounded ear, circumaural headphones can be designed completely sealed to prevent the head of any less intrusive external noise. Because of their size, circumaural headphones re, there are some units weighing more than 500 grams. Headband and ear pads requirements designed to reduce the discomfort caused by the weight.

Supra-aural: Supra-aural pad sitting on top of the ear headphones, rather than around them. They are usually bundled with personal stereos in the 80s. This type of headphones, generally tend to be smaller and lighter than circumaural headphones, which reduce the external noise attenuation.

Earbud: They are a smaller size, directly on the outside of the ear headphones, but it is not completely surrounded. They are generally inexpensive, is its portability and convenience of all ages. Since they can not provide any information they often use high-volume to cover up the environment from the user, thus increasing the risk of hearing loss noise. [2] 90 in the 20th century and 2000s, earbuds became a common type bundled with personal music device isolation.

In-ear: Sometime it called as canalphones ,this kind of earphone are inserted directly into ear canal. It similar like earbuds,it portable and act as earplugs to block out environment sound. There are two main types of ear: General and customization. General canalphones provide one or more stock sleeve size (S) to fit various ear canal, which is commonly made of silicone rubber, elastomer, or foam noise isolation. Custom canalphones is installed on everyone’s ears. Ear tubes used in the manufacture castings made and create a custom casting silicone rubber or elastomer, to provide additional comfort and noise isolation plug. As it involves personal labor, custom ear than in the general ear and very low resale value, because they are less expensive and may be suitable for others.

However ,the design of the earphone’s sharp or the music quality also important. This is because,

different user has different needed. Example ,the user need the bass boots earphone so that they can listen the music more bass. In addition, for spot user the earphone can hang at ears and not easy to drop down ,so that user can enjoy the music and no need worry about the earphone drop down.

4.3 Printer

Printer is peripheral which produces hard copy (permanent human-readable text and / or graphics) files stored in electronic form, usually paper or transparencies, such as physical print media, documents. Many printer is mainly used for local peripheral devices, and a printer via a cable connection, or in most newer printers, the computer’s USB cable to connect to it as a file source. Some printers, commonly known as a network printer with a built-in network interface, usually wireless and / or Ethernet-based, and can be used as any user on the network hard-copy devices.

The following printing technologies are routinely found in modern printers:

Toner-based/Laser printers: This kind of printer rapidly produces high quality text and graphics. As digital copiers and multifunction printers (MFP), laser printer uses electrostatic printing process, but the difference is that the image is made up of a printer’s photoreceptor cells across the laser beam directly scan analog copiers.

Liquid inkjet printers: Inkjet printers operate by propelling variably-sized droplets of liquid or molten material (ink) onto almost any sized page. They are the most common type of computer printer used by consumers.

Dye-sublimation printers: A dye sublimation printer (or dye sub printer) is a printer using a thermal transfer printing process using a plastic card, paper or canvas media such as dyes. This process is usually used to lay in a color panel ribbon, once a color. Dye sub printer is mainly used for high-quality color applications, including color photography and text suitable for the disadvantaged. Once the high-end print shops, dye-sublimation printer provincial consumers increasingly are used to dedicated photo printer.

Inkless printers: There is two type of inkless printer. They are Thermal printers and UV printers. The work of selective heating thermal printer thermal sensitive paper of special areas. Black and white thermal printer for cash registers, ATM machines, gasoline and some old cheap fax machine. Color can be achieved with special paper, different temperatures and heating rates of different colors. One example is the Zink technology.

Xerox is developing a inkless printer will use a special reusable paper, chemicals, UV-sensitive coating of several microns. The printer will use a special UV light bar will be able to write and erase the paper. As of early 2007, the technology is still in development and the printed page can only be maintained between 16-24 hours before fading text.

5.0 Conclusion:

In this era ,the devices already improve by the time. So human can enjoy and get more benefit from the new design of devices. So ,ergonomic devices is important that can make our life more good. However ,we must rest around every 30min while using computer ,and also while rest can do some office exercise. This can maintain our body blood flowing.