Example Of Technical Description –Computer

MouseIntroductionPart definition and functionOperating principleConclusion

http://computer.howstuffworks.com/mouse.htm

What is a computer mouse? A mouse is an external computer hardware

device that allows a user to control the motion of a computer cursor and select objects on the screen by moving and clicking the device. During the 1980s, computer mice became the dominant way for people to interface with personal computers after testing with various devices showed it to be the most convenient and simple to use. The mouse works on the basic principle that the movement of the device is translated into the movement of the cursor on the screen.

 

Part Definition and Function

Top Casing The top casing of a computer mouse is a hard, Curved sheet of plastic that is

designed tofit comfortably in the palm of the hand. Can protects the inside parts of the

mouse.

Right‐click and Left-click cover The right‐click cover is a small, Curved

piece of plastic on the top , Front of a computer mouse that can be depressed to transport a signal to a receiver on a circuit board inside the mouse. This receiver translates the mechanical

action of “clicking” into instructions for the computer.

The left‐click cover works effectively because it is wide enough to be easily

depressed by the user.

Scroll wheel The scroll wheel is a small wheel

overlaid with rubber .That is located between the right‐ and left‐click covers .

That connects to the internal circuit board though a system of tiny gears.

The position so that it can be easily turn by one finger. The scroll wheel allows the user to navigate up and down in a user interface window.

Bottom casing The bottom casing is a hard shell

of plastic on the underside of a computer mouse.

The function is to protects the inner parts.

• Track ball

Small rubber sphere ball is captured through a system of gears and translated to an electronic signal to control the motion of the pointer on the computer screen.

• Internal circuit board

Is an electronic component made of a copper sheetEtched with conductive pathways which connect different kinds of electronic equipment.Housed inside the protective covers of the mouse.collects and translates information from the user

• Connecting wire/cord

wires sealed in a plastic sheathsends information in electronic signals The cord is several feet long.

• Port

Plastic and metal connecting piece at the end of the cord with prongs.The round piece is made from metal, with metal pegs inside that ensure a correct and snug fit in the proper port.

The DSP detects patterns in the images and examines how the patterns have moved

since the previous image.

Based on the change in patterns over a sequence

of images, the DSP determines how far the mouse has moved and

sends the corresponding coordinates to the

computer.

The computer moves the cursor on the

screen based on the coordinates received

from the mouse.

The CMOS sensor sends each image to a digital signal processor

(DSP) for analysis.

This happens hundreds of times each second, making the cursor appear to move very smoothly.

Operating Principle

the sensor on the bottom of the mouse.

Most optical mice use a small, red light-emitting diode (LED) that bounces light off that surface onto a complimentary metal-oxide semiconductor (CMOS) sensor.

Conclusion

A mouse is a simple, easy‐to‐learn, device for interacting with a computer that translates actions of the user directly into movement and actions on the computer interface. It does require some practice to learn the coordination of controlling the mouse, but once a person understands the concept of how the mouse works, it is easy to control.

Optical mice have several benefits over track-ball mice: • No moving parts means less wear and a lower chance

of failure. • There's no way for dirt to get inside the mouse and

interfere with the tracking sensors. • Increased tracking resolution means a smoother

response. • They don't require a special surface, such as a mouse

pad.