ocr: 3 When the laser beam hits the CDI L cither hits a smoouh area of The CD ROM 11 Tho detector" comprises tho surtace called a land and is retlected directy backi into the a aser diode which omits a detecior or it hits a depressed area on the surtace: called. a pit Drive beam of light which passos which scamers thel ghts so thati it is not resectedl backi no the through a prism. and detector. objective lons andi a accurately: locusod by a - / 2 The disk s under spun the by a disk motor. This the speed ocusing coil to: striko the of which varies according to the position of CD which rotates above ...