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Unlike the incremental encoder, the absolute encoder obtains position information. The absolute encoder has multiple rings etched on the disk. The first ring has one light segment and one dark segment, each successive ring has doubled the number of segments from the previous ring. The number of rings determines the number of bits of resolution of the encoder. This can be used to determine the number of steps that an encoder can detect. The output of the device is a binary number. As the disk turns, the binary number increases. Absolute encoders typically use a binary code called the gray code, in which only one bit changes as the sequence increases. The binary number or gray code number can be used to determine shaft position.