I. Warming up

1. Have you shifted from wired devices to wireless devices yet? When did you do it? Dwell on the pros and cons of these two methods of data transmission.

2. What wireless devices do you use? How do they function?

II. Reading

Read the text and consider the questions below.

How Does a Wireless Keyboard and Mouse Work?

By S. Sukumar

With the advent of new technologies in wireless communication, many wired devices are transformed into wireless ones. Among those wireless devices, wireless keyboard and mouse are being widely used. This article makes it easy for you to understand the working of wireless keyboards and mice .

The working of wireless keyboards and mice is not as complicated as you think. It just involves the basic concept of wireless technology, that is, some data is transmitted from a device in the air and the same data is retrieved by another device. Wireless keyboards and wireless mice are portable and it is very useful, especially if you have to give some powerpoint presentations in your office. We don’t even have to compromise on its efficiency. These devices are very compatible and its working is very precise. The wireless keyboard and mouse uses rechargeable batteries for its working. Let’s start with the working of these wireless devices.

Working of a Wireless Keyboard

The working of a wireless keyboard is very simple. If you take the case of wired keyboards, the keyboard is directly connected to the computer, and the computer receives the signal from the keyboard through cable. But what happens in the case of wireless keyboards? The medium of transmission of signals is through, infrared, or radio frequencies (RF). The basic thing to be understood here is that, the data from a keyboard (transmitter) is transmitted to the computer through USB (Universal Serial Bus), which acts as a receiver and receives the signals from the keyboard. The wireless keyboard also works with Bluetooth technology that has a wider range than infrared. Infrared keyboards, do not have a wide range, and it works in the line of sight of the computer. This means that, infrared keyboards cannot be used away from the computer.

There is an Integrated Circuit (IC) chip in the computer, that receives all the information that comes from the keyboard and transfers it to the Operating System (OS) of the computer. The encoded data from the keyboard is processed and decoded in the CPU (Central Processing Unit) and it is displayed in the monitor of the computer. Each letter in the keyboard has a code. For example, the code for T is U+0054.

Types of Wireless Keyboards

Optical Keyboard

Optical keyboard works with two main components – light emitting diodes (LED) and photo sensors. These two components are embedded in the Printed Circuit Board (PCB). LEDs work using the principle of “electro luminescence” and photoelectric sensors “detect the light rays” from any device. The horizontal and vertical light beams are emitted from the LEDs and received by the sensors. These light beams are blocked by the prompted key in the keyboard and thus the particular key is identified.

Laser Keyboard

The image of the keys in the laser keyboard is projected or displayed on a flat surface. But how is it done? The movement of a user’s fingers on the keyboard is monitored by the complementary metal-oxide semiconductor (CMOS) which are power saving semiconductors or Virtual Interface Processing CoreTM which is a infrared sensor. The virtual interface processing core is a sensor chip that examines the location of the actuated key. The image of the key is displayed using a red diode laser on the projector (screen) and the image is enlarged using diffractive optical elements.

Working of a Wireless Mouse

Just like any wireless device, wireless mouse has two basic main components – transmitter and receiver. RF wireless mouse and Bluetooth wireless mouse works same like the wireless keyboards. The other components of a wireless mouse are mouse controller, ceramic capacitors, 26.690 MHz crystal for transmission. The mouse has a standby mode and it transmits only when you are doing an action, example, clicking. The computer has a printed circuit which has all data of the mouse.

Types of Wireless Mice

Optical Mouse

The essential components of an optical mouse are light emitter (LED lights) and light sensors (CMOS sensor). Red light which is emitted from the red LED is used to track the movements of the mouse. The CMOS sensor is used to capture the image of the mouse movements. After capturing, it sends each image to a Digital Signal Processor (DSP). The DSP analyzes the pattern of each image that has been sent by the CMOS and examines how these images have changed, comparing to the previous image. The pattern of mouse movements are marked on the coordinate axes. The monitoring of the mouse movements and capturing the images are done very precisely, thereby providing a smooth movement of the cursor on the screen. Dots Per Inch (DPI) technology is used to give a fine resolution to the image, just like megapixels in mobile phones. Optical mouse uses 400 to 800 DPI for image resolution.

Laser Mouse

The working of laser mouse is almost same as that of an optical mouse with few differences. The laser mouse has more resolution (2000 DPI) as compared to optical mouse and laser mouse uses invisible laser rays to detect the movements of the mouse.

Wireless keyboards and mice are important input components of a computer. So, it is necessary to know the best wireless keyboard and mouse available in the market that will be suitable for your computer. Buy the best one and enjoy working with it!


1.How does a wireless keybord function?

2. What are the peculiarities of a wireless mouse?

3.What is the difference between the optical technology and laser technology?

III. Focus on the language

1. Give a brief description of an input device (mouse, keyboard) and its functions. Make use of the following groups of antonyms.

wired – wireless

transmit/emit – retrieve/receive

encode – decode

directly connected to (the computer) – used away from (the computer)

2. Choose any wireless device and enumerate the stages of its work by using the following verbs.

Display, capture, identify, monitor, project, examine, analyze, mark, track.

IV. Problem solving

1. Role play a conversation between a shop-assistant and a client who wants to upgrade his computer. The shop-assistant should offer various models of peripheral devices and explain to the client advantages and disadvantages of wired and wireless devices.

2. Role play the situation: You are a college teacher. Explain to your students the principles of work of wireless devices. Speak about the existing technologies and compare them.

V. Useful tips for your presentations

To be able to persuade people in 5 minutes or less, consider the following tips about auditory vs. visual thinking given by Iris Shoor:

Do you think mostly in words or images? When you observe a new product (like, say the new iOS 6) do you read about it first, or rush straight to the images?

In advertising campaigns, where convincing people is everything, you’ll always see both languages used together – strong copy which goes hand in hand with an interesting image. Some will remember what they’ve read, others will remember what they’ve seen. The segmentation between these categories originally came from researchers exploring different learning styles to improve the ways students are taught by understanding how different minds work.

How to identify if someone thinks in an auditory or visual way? I usually ask people to describe a certain event – like the last party they attended or the worst flight they were on. You’ll soon notice that some use names of people and places, times and phrases, while others describe an image – the size of the room, the colors and how people looked. Notice the different verbs they use. Auditory thinkers will tend to use verbs such hear, listen, explain. Visual thinkers are much more likely to describe a situation using see, look, watch. You can find out which category you belong to here.

How to convince better by understanding auditory vs. visual thinking

Use both languages: When I pitch a new idea, much like in advertising, I try to balance between the text and visual. It can be an email with a written suggestion and a screenshot, or a presentation slide with an important message complemented by an image representing the same idea.

Create a visual using words: The same applies when talking about an idea. You don’t usually have enough time to prepare a visual, but you can construct it with words. Creating a vivid picture in someone’s head – the time of day, the location, the colors, is one of the best ways to have a visual thinker remember and understand your ideas.

Give visual thinkers something to doodle on: I’ve noticed that the larger the whiteboards we use in meetings, the better the outcome. I always have papers, a whiteboard or an iPad handy when brainstorming with others. At one point we’ve replaced all the tables at the office to glass ones, which can be doodled on. This small step has increased everyone’s productivity. Here’s an interesting finding based on study published in the journal Applied Cognitive Psychology: “subjects given a doodling task while listening to a dull phone message had a 29% improved recall compared to their non-doodling counterparts”.


VI. Working on the project

You are an IT technician. Your boss has given you the task to upgrade the office computers. You should prepare a 5-minute report on the options available in the market and work out the most optimal solution. Persuade your boss to support your suggestion. Follow the useful tips above.