Page 44 - FUNDAMENTALS OF COMPUTER

NPP

44 Fundamentals of Computers NPP

1.18 Mouse 1.18 _mCg
A mouse is a pointing device or locater `h EH$ bmoHo$Q>a `m nm°B§qQ>J `wpŠV h¡ & Š`m|{H$ `h
which points to a particular location on the EH$ {deof q~Xw H$mo Xem©Vm h¡Ÿ& Bgo EH$ N>moQ>o ßbmpñQ>H$
screen. It is packed in a small plastic box. When ~m°Šg _| ~Zm`m Om gH$Vm h¡Ÿ& O~ _mCg H$mo Q>o~b na
the mouse moves on the table, the pointer also BYa-CYa gaH$m`m OmVm h¡, Vmo d¡go-d¡go ñH«$sZ na ^r
moves on the screen. Therefore different items EH$ nm°BªQ>a J{V H$aVm h¡& Bg{bE Cn`moJH$Vm© ñH«$sZ na
on the screen can be selected by user. A mouse H$B© AmB©Q>åg (AmBH$m°Ýg) H$mo MwZ gH$Vm h¡ Ÿ& EH$ _mCg
may have one, two or three buttons, There are na EH$, Xmo `m VrZ ~Q>Z hmoVo h¢ Ÿ& VrZ àH$ma Ho$ _mCg
three types of mouse: hmoVo h¢…
1. Mechanical mouse. 1. _oHo${ZH$b _mCg
2. Optical mouse. 2. Am°ßQ>rH$b _mCg
3. Optomechanical mouse. 3. Am°ßQ>mo_oHo${ZH$b _mCg
Mechanical mouse _oHo${ZH$b _mCg
It has two rubber wheels, with there per- Bg_| a~a Ho$ Xmo ìhrb hmoVo h¢ Ÿ& BZHo$ Aj Amng _|
pendicular to each other: b§~dV hmoVo h¢ …
Each wheel is connected to a variable re- àË`oH$ ìhrb H$mo EH$ d¡[aE~b ao{gñQ>a ¶m nmoQ>|{e`mo{_Q>a
sister or potentiometer. When the wheel ro- go Omo‹S> {X`m OmVm h¡Ÿ& O~ ìhrb Ky_Vm h¡ Vmo nm|Q>o{e`mo{_Q>a
tates around its axis the change in resistance H$m à{VamoY ~XbVm h¡Ÿ& Bg ~Xbo hþE à{VamoY go hr _mCg
gives the distance travelled. Ûmam V` H$s JB© Xyar kmV H$s OmVr h¡Ÿ&

Optical mouse Am°pßQ>H$b _mCg

Cable for Computer
LED
Surface
Sensor
(Pad)

Reflected Light Red Light beam

Fig. 1.6: Optical Mouse

Modern optical mouse has three important AmYw{ZH$ Am°pßQ>H$c _mCg _| VrZ _w»` VËd
functional elements: hmoVo h¢§:
(1) LED (1) LED

(2) Sensor (Photodiode) (2) g|ga (\$moQ>moS>m`moS>)
(3) DSP Processor. (3) DSP àmogoga