AT&T ISB7005 User Manual

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The type of screen your HDTV has (wide-screen or standard-screen) determines how the receiver 
displays programs on the screen. The picture format for an HDTV is a combination of aspect ratio 
and screen resolution and is diff erent for standard-screen and wide-screen HDTVs.

An aspect ratio is the ratio of the width to the height of the TV screen. The aspect ratios diff er 
because the television industry manufactures both standard-screen and wide-screen HDTVs to 
appeal to consumer viewing preferences.  

The screen resolution indicates the amount of detail that the picture displays. Resolution is identifi ed 
by the number of display lines on the screen. The techniques that an HDTV uses to “paint” the 
picture on the screen are referred to as progressive and interlaced.

With the progressive scanning method, the lines are drawn on the screen one at a time in 
sequential order. Progressive scanning results in a more detailed image on the screen and is also less 
susceptible to the fl icker commonly associated with interlaced scanning. The interlaced method 
involves refreshing pixels in alternation — fi rst the odd lines and then the even lines. 

For advanced setup, select the screen resolution that your TV can support. Refer to your Feature 
Guide and HDTV owner’s manuals to choose the proper screen resolution (480i, 720p, 1080i, or 
1080p) for your setup. 

For example, a screen resolution of 1080i indicates that the screen shows 1080 lines in an 
interlaced display, and 720p indicates that the screens shows 720 lines in a progressive display.

A standard-screen HDTV has a 4x3 
aspect ratio. The screen is 4 units wide 
for every 3 units tall.  

A wide-screen HDTV is one-third wider 
than a standard-screen HDTV. The screen is 
16 units wide for every 9 units tall.

A screen resolution of 480i fi lls the 
screen.

A screen resolution of 720p, 1080i, or 
1080p fi lls the screen.