Focus
Pattern Description: Consists of capital letter “E”s and “M”s alternating across the screen. Sometimes refered to as a MEME pattern. The closely spaced elements of these letters makes it easy to judge the effects of focus adjustments.
Pattern Usage: Used as a reference signal for viewing the effects of focus adjustments across the entire screen. Since it is difficult for CRT displays to achieve uniform focus across the entire screen, multiple focus adjustments and/or compromise settings of the focus control(s) is necessary to achieve acceptable focus. The focus adjustment method will be different depending on the number of focus controls and whether the device is designed to display video or computer data.
A video display with only one focus control should be adjusted for optimum focus at the center of the screen (where most action occurs). A data display with only one focus control should be adjusted for compromise focus between the center of the screen and the edges of the screen (adjusting for sharpest focus at a midpoint usually works well).
A video or data display with two focus controls is usually adjusted for best center focus with one of the controls and best edge focus with the other control.
Ramp
Pattern Description: Pattern makes smooth transition from 100% black on left to 100% white on right. When electrical video signal is viewed at horizontal scan rate, it appears as linear ramp from black level to white level.
Pattern Usage: Useful for visually checking
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