mouse has a that rotate in any MOUSE direction. Moving the mouse will cause the ball to rotate and this determines its directions. The A standard mouse consists of the following mouse uses two metal rollers that detect its components: horizontal and vertical movements. Connected to the end of the metal rollers are a disk-like  Housing – the one you hold in your hand encoder wheels that rotate in between two and move around on your desktop optical beams. The signal of the beam will be  Method of transmitting movement to the interrupted and this will generate the electrical system – can either be Ball/roller or signals. optical Image from www.bristol.ac.uk  Buttons – used for making selections  Interface – connects the mouse to the system. Conventional mice use wire and connector while mouse use frequency or transceiver. Development Computer mouse was invented by of Stanford Research Center in 1964 and was originally called “X-Y Position Indicator” Shown above is a sample mechanical mouse with a for a display system. In 1973, used the track ball in the underside that makes contact with the same mouse design in its experimental working surface of the mouse. computer called “Alto”. In 1979, The mouse ball can be removed by rotating the (owner of Apple/) after seeing what a mouse ball housing in a counter clockwise direction. mouse can do in the “Alto computer”, decided to The mouse ball (rubber ball) rolls as you move the incorporate the mouse system together with the mouse. Its movements are translated into electrical signals transmitted to the computer across the cable. GUI (Graphical ) to his latest computer design called “Lisa”. It was in 1984 when Apple introduces Macintosh as the 2. – was developed in 1999 by mainstream of their computer design. Macintosh Agilent and it works like a tiny became a hit, and because of this the mouse camera that takes thousands of pictures every development was credited to Apple . second. It is designed to work on every surface without the use of a mouse pad. It uses a LED (Light Emitting Diode) to transmit the light beam and a () to detect the movement relative to underlying surface.

An optical mouse developed by is shown above. It works by illuminating a LED on its underside Image from www.en.wikepedia.com and uses an optoelectronic sensor to detect relative motion on different types of surface. The first mouse design developed by Douglas Engelbart is shown above. It was made from wood and a metal wheel. Physically it looks very primitive, 3. Laser Mouse – was developed by Sun Micro but it works. system in 1998 and it works like an optical mouse, but it uses a small infrared laser instead of a LED. Using an infrared laser increases its tracking capability by 20 times as compared to Types of Mouse conventional mouse. The mouse sensitivity and 1. Mechanical Mouse – was invented in 1972 by Bill English while working with Xerox. The

1 resolution also increases but the power Mechanical mouse utilizes less power compared consumption decreases on this type of mouse. to an optical mouse, but this is not a serious issue for PC users. Users are more focus on the mouse efficiency.

How Mechanical Mouse Works

Mechanical mouse always depends on the rotation of the track ball in determining its speeds, directions and movements. The track ball is connected to two rollers which individually determine the X (horizontal)and Y (vertical) directional motion of the mouse. As shown Image from www.bbspot.com below each roller has its own chopper wheel (looks like a bicycle wheel) that the Shown above is a sample laser mouse developed by beam transmitted by light source and received Microsoft. Compared to optical mouse, laser mouse by the detector. The wheel passes in between has greater resolution because it uses infrared the light source and detector causing the light . beam to break. The break in the light beam is converted to electrical signal that correspond to Optical Mouse Versus Mechanical Mouse movement in the mouse pointer.

Working surface

Optical mouse can work on different landscape compared to a mechanical mouse. Its optical technology can accurately determine the movement, direction and speed of the mouse regardless of the contour in its working surface. Mechanical mouse will encounter problem once the working surface is bumpy (not smooth). However, optical mouse will have problem working in glossy and transparent surfaces. The light may not bounce back directly to the Shown below is the inside of a mechanical mouse. It optoelectronic sensor and this may cause the has the mouse circuitry, infrared LED and sensor, pointer to drift unpredictably during operation. mouse buttons, chopper wheel and the ball that touches the desktop and rolls when the mouse Life expectancy moves. Optical mouse is expected to have a greater life expectancy compared to a mechanical mouse. Optical mouse is designed with no moving parts, which means less wear and a lower chance of failure. The mechanical mouse, because of its design, has a life expectancy of 1 to 2 years only. Tolerance against dirt and dust Mechanical mouse uses a trackball that acquires Image from www.HowStuffWorks.com a lot of dirt and dust during operation. These requires mechanical mouse user to frequently The rollers inside the mouse are in contact with clean the mouse. Optical mouse has no rolling track ball. As shown in the picture below, the parts thus; dust or dirt cannot get inside the white rollers protrude and touch the ball. The mouse and affect the tracking sensor. Optical first roller detects the horizontal movements of mouse does not require cleaning except for the the mouse, while the other roller which is placed dust debris collected on its underside. 90 degrees of the first roller detects the vertical movements. When the ball is rolling, one or Power consumption both rollers rotate as well.

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PC Technology 2 A mouse has an on-board that converts these electrical signals into its binary equivalent. The chip will then send the 1’s and 0’s combinations to the PC using the mouse cord. A sample mouse processor developed by is shown below.

The rollers are connected to a shaft and the shafts spin the chopper wheel between the light transmitter and receiver. The chopper wheel (sometimes called “decoder disk”) has 36 holes around its edge that is used to alternately break and restore the light signal. It uses an infrared LED to transmit the light and an infrared sensor to receive it as shown below. Image from www.HowStuffWorks.com

[How Mechanical Mouse Works, Pages 7-12 of 32]

How Optical Mouse Works As discussed earlier, an optical mouse works like a tiny camera that produces thousands of snap shots every second. Built-in CMOS (Complementary Metal Oxide Semiconductor) sensors transmit these images to the DSP (Digital Signal Processor) for processing. The DSP will analyze the image patterns and recognize the changes from one image to Image from www.HowStuffWorks.com another. Based on these changes, the DSP will

determine how far and which direction does the mouse travels and sends the coordinates to the Shown below is a close-up look of an infrared PC. The computer will move the mouse pointer LED on one side of the chopper wheel and an to the location (coordinates) sent by DSP on the infrared sensor on the other side. As the screen. This process is done continuously every chopper rotates, it breaks and restores the light second so it appears that the mouse pointer is signal alternately. These light pulses are moving smoothly. converted into electrical pulses which are directly related to the movement of the mouse pointer on the screen. There are also 2 pairs of infrared transmitter and sensor on each side of the wheel; theseare used to determine the direction of wheel rotation.

Image from www.HowStuffWorks.com Image from www.HowStuffWorks.com Shown above is a sample of an optical mouse underside. It has a LED and a photodiode. Wireless Mouse

Most wireless mouse uses the RF (Radio Frequency) technology to transmit data to the computer. A wireless mouse has a transmitter (connected to the mouse) and a receiver

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(connected to the PC). RF mice use different A wireless receiver can be a card or any frequencies to avoid conflict. It external plug-in device that utilizes computer has a transmission range of 6 feet to 33 feet and ports (commonly used is USB). operates at 27 MHz RF is better than infrared Mouse (IR) technology because IR can only accommodate short-range transmission and Bluetooth is also known as PAN (Personal Area requires the line of sight between the transmitter Network) and is one of the most common RF and receiver. Shown below is a sample wireless technology used in wireless mouse. A Bluetooth mouse with a . This docking mouse has a range of 33 feet and operates at a station is where a mouse is placed when not in range of 2.4 GHz. It can accommodate multiple use. The docking station also serves as charger Bluetooth signal coming from other devices at for the wireless mouse battery. one time, but uses the techniques called frequency hopping to avoid signals interference.

How Wireless Mouse Works

The transmitter of a wireless mouse resides Shown above is a Bluetooth mouse developed inside the mouse housing. It converts hand by Targus Technologies and it has the Bluetooth motion into radio signal that is sent to the PC. logo on top of the case. It also has a built in Shown below is a wireless mouse circuit with a transmitter and a USB interface receiver. transmitter circuit on top of it. The circuit has a Biometric Mouse processing chip that converts electrical pulses to Biometric mouse is a type of mouse that has an RF signals. added security to protect the computer system against unauthorized access by disabling the mouse functions. It has an integrated fingerprint reader in the mouse housing. This feature enhances the system security by allowing only authorized user to access the system using a mouse. This is more convenient than typing a password to secure login. The receiver is directly connected to the PC. It accepts the signals coming from the mouse transmitter decode the signals and transmit it to the mouse driver software which is managed by the PC . Shown below is a sample wireless mouse receiver that is connected to the USB port of a PC. Image from www.HowStuffWorks.com

Shown above is a sample biometric mouse developed by Microsoft. The fingerprint reader is located on top of the mouse housing, but there are also designs where the fingerprint reader is on the side of the mouse. To activate its biometric functions, a software program that comes with the mouse must be installed first.

Image from www.adcomarketing.com Advantages of Computer Mouse

Computer mouse is considered a primary device because of the following reasons:

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constantly moved on a flat surface. Dust and dirt 1. It can work in small spaces because of its are easily picked up by this movement. Shown physical design and how it is used. Computer below is a sample dirt and debris being picked- mouse only requires a small working space and up by a mechanical mouse during operation. its movement is bounded by the size of the mouse pad. Shown below is a sample of a mouse pad that is used as a working ground in using and operating the mouse. Whenever the mouse movement goes beyond the edge of the mouse pad, the user by instinct will immediately put the mouse back at the center of the mouse pad. Mouse Connectors 1. Serial Connector – the oldest connector used in interfacing a mouse to a PC. It is a DB 9-pin connector (shown below) that uses a serial transmission technology. This connector is used in most PC system with AT and Baby AT 2. It is designed to adjust to the granularity of form factors. It uses an movement because it is capable of detecting two external port with cable connected to dimensional (horizontal and vertical) COM1or COM2 of the motherboard. movements. There is a direct relationship between the user’s hand control and the movement (direction, speed and distance). As shown below, a computer mouse can translate user hand movement into on-screen pointer movement.

2. PS/2 Connector – also known as 6-pin mini DIN connector (shown below) which is commonly used in LPX, NLX and ATX motherboard form factors.

3. It is low cost because the design is simple. It has few components (electronics and mechanicals) only. The components are inexpensive and are readily available in the market.

3. USB Connector – the most common Disadvantages of Computer Mouse mouse connector being use today. Because USB is a universal port (shown 1. It requires certain amount of eye-hand below), it can replace both standard coordination in using a computer mouse. It may serial and using a single be hard and awkward at first, but these skills port. The latest mouse model, including can easily developed by user because of those with special features like wireless frequent use and practice. and biometric mouse uses USB port. 2. Mechanical mouse are prone to dust and dirt which may cause problem in using it. Mechanical mouse has a track ball that is

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running across the middle of the rollers. Use a clean cotton swab soaked in cleaning fluid (alcohol or other) to remove the dirt from the roller. 5. Close the mouse and return the ball to the mouse ball housing. Tips in Purchasing a Mouse Mouse Troubleshooting  Choose the right type of mouse  No Mouse Movement connector based on your motherboard -Check if the mouse (PS/2) is properly form factor. connected to the PS/2 mouse port and not on  A connector is available to the keyboard port. The color label of these convert USB to PS/2 and PS/2 to serial devices must be considered to avoid confusion as shown below. between the ports. Turn off the computer and reconnect the mouse to the right port. -Check the BIOS setup and make sure that the PS/2 mouse port is enabled. - If the mouse still does not work after turning the computer on, try to isolate the problem by using the same mouse to other computer. If the mouse works in other computer, then the

 Choose a mouse with additional buttons problem is on the motherboard mouse port. If for better functionality. the mouse did not work in other computer, then the problem is probably on the mouse.  Choose a mouse with ergonomic design that is fitted to the user.  The mouse pointer periodically stop  Buy a mouse with for easy moving document . - For mechanical mouse, clean the mouse roller  Expect a mouse (mechanical) to last 1 ball. to 2 years. -For optical mouse, clean the optical lens Cleaning a Mechanical Mouse located on the mouse underside using a clean 1. Turn the mouse upside down and cloth. Inspect the LED if there is debris -up. remove the mouse ball retainer ring Gently blow the debris away from the lens. by rotating it on a counter clockwise - Optical mouse may have problem on a very direction. Removing the retainer ring glossy or highly reflective working surface will expose the rollers and ball because of its optical technology. Check the housing. mouse pad and make sure that it does not cause tracking problems.

Conflict -Interrupt conflict does not normally occur if a user is going to connect the mouse using the standard port. Basically a mouse is assigned to use IRQ12 in modern motherboard design. The conflict occurs when a different interface is used to connect the mouse to a PC, like an adapter card.

2. Remove the mouse ball and wash it with -To check if there are conflicts, access the warm soapy water. Dry the ball using a clean Device Manager piece of cloth. and resolve the conflict. 3. Open the mouse housing and use a can of  Mouse extra or scroll does not compress air to blow away the dust and dirt work inside the mouse housing. - Mouse may not be a hybrid design, get on-line 4. Check if there is build-up of dirt in the mouse and rollers. The build-up normally looks like a stripe download the proper driver for the mouse.

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