Page 63 - FUNDAMENTALS OF COMPUTER

NPP Computer Basics and Windows Fundamentals 63

made up of thousands of such pixel glowed H$aVo h¢Ÿ& EH$ B_oO Eogo hOmam| {nŠgoëg Ho$ H$maU ~ZVr h¡
due to computer command. When the pixel Omo {H$ H$åß`yQ>a H$_m§S> Ho$ H$maU àH$me_mZ hmoVo h¢Ÿ& O~
density is higher sharper image is formed. The {nŠgoc H$m KZËd A{YH$ hmoVm h¡ Vmo AÀN>r B_oO ~ZVr h¡Ÿ&
distance between two pixels is called dot pitch. Xmo {nŠgoëg Ho$ ~rM H$s Xyar H$mo S>m°Q> {nM H$hVo h¢Ÿ&
The electron beam is deflected by two BcoŠQ´>m°Z ~r_ Xmo BcoŠQ´>mo_¡½Zo{Q>H$ H$m°Bcm| Ho$ H$maU
electromagnetic coils. The beam is moved from {dM{cV hmoVr h¢Ÿ& ~r_ ~mE§ go XmE§ {dM{cV hmoVr h¡, gmW
left to right. This is called trace. When it is hr `h D$na go ZrMo ^r AmVr h¡Ÿ& Bgo hr Q´>og H$hVo h¢,
moved from right to left it is blanked. This is co{H$Z O~ Bgo XmE§ go ~mE§ cm`m OmVm h¡ Vmo H¡$WmoS> go
called retrace. Next scan line is started just
below the previous line. That means the beam ~r_ Zht {ZH$cVr AV: `h ãc¢H$ hmo OmVm h¡Ÿ& Bgo [aQ´>og
also moves from top to bottom. When the beam H$hVo h¡Ÿ& AJcr cmBZ nwamZr cmBZ go R>rH$ ZrMo ewê$ H$s
reaches the bottom right, it is again sent to the OmVr h¡& Bg Vah go ~r_ O~ g~go ZrMo nhþ§M OmVr h¡ Vmo
top left, This is called vertical retrace. During nwZ: Bgo D$na nhþ§Mm`m OmVm h¡, Bgo d{Q>©H$c [aQ´>og H$hVo
this interval also the beam is blanked. Refresh h¡§Ÿ& Bg Xm¡amZ ^r ~r_ H$mo ãc¢H$ H$a {X`m OmVm h¡Ÿ& EH$
rate refers to the number of times an screen is g|H$S> _| {H$VZr ~ma ñH«$sZ na {nŠMa ~Zr, Bgo [a\«o$e
traced in one second. NPP aoQ> H$hVo h¢Ÿ&

Fig. 1.14: CRT Monitor
Advantages of CRT Monitors CRT _m°{ZQ>a Ho$ cm^

1. CRT monitors have very high contrast ratio. 1. BZH$m H§$Q´>mñQ> ~hþV AÀN>m hmoVm h¡Ÿ&
2. High Speed Response. 2. BZH$s J{V AÀN>r hmoVr h¡Ÿ&
3. They have excellent viewing angle. 3. BZH$m Ñí` H$moU AÀN>m hmoVm h¡Ÿ&
4. It is reliable and proven a display techno- 4. `h EH$ {gÕ d ^amogo_§X VH$ZrH$s h¡Ÿ&
logy.