The principle used in most encoders (linear or rotational) is the same: an optical device. We shall study two types of rotational encoders briefly. Figure 3.12 shows an incremental encoder.
Amy McDougall/Barone (Monica Horan) becomes Robert Barone's second wife (in season 7), and is the best friend of Debra, who introduces her to Robert. A recurring character for the first seven seasons of the series, Amy became essentially a regular cast member for the remainder of the show's run.
It showed another side of the Emmy-winning actor, one that would be best exploited in Raymond as the curmudgeonly Frank Barone. He's just obnoxious in a nice way, just for laughs, Boyle said of the character in a 2001 interview.