A measuring instrument comprising: a measure on which a code having a plurality of color patterns is printed, each of the color patterns having a plurality of digits to which values of a N-ary number are assigned with N being 3 or more, one of different colors respectively corresponding to one of N-ary values being assigned to each pattern corresponding to each digit included in each color pattern, the patterns corresponding to each digit being arranged in a second direction (X) intersecting a first direction (Y), a Hamming distance between adjacent color patterns in the first direction (Y) being 1, and an amount of change in the value at one of the digits included in the adjacent color patterns being 1, the patterns arranged in the second direction (X) all having the same width (P1) in the first direction (Y); a plurality of first readers arranged in the second direction (X) and configured to optically read colors of first ranges in a plurality of first patterns (41 to 45) corresponding to digits except a least significant digit among the color patterns, respectively, the first ranges in the first patterns being arranged in the second direction (X); and a plurality of second readers (22a to 22c) arranged in the first direction (Y) and configured to optically read colors of second ranges (32a to 32c) in a plurality of second patterns (46a to 46h) arranged in the first direction (Y) corresponding to patterns of the least significant digit among the color patterns, respectively, the adjacent second readers being arranged in the first direction (Y) at an interval (P2) different from the width (P1) of the pattern in the first direction (Y), and one of the second readers being arranged in the second direction (X) side by side with the plurality of the first readers . a measure on which a code having a plurality of color patterns is printed, each of the color patterns having a plurality of digits to which values of a N-ary number are assigned with N being 3 or more, one of different colors respectively corresponding to one of N-ary values being assigned to each pattern corresponding to each digit included in each color pattern, the patterns corresponding to each digit being arranged in a second direction (X) intersecting a first direction (Y), a Hamming distance between adjacent color patterns in the first direction (Y) being 1, and an amount of change in the value at one of the digits included in the adjacent color patterns being 1, the patterns arranged in the second direction (X) all having the same width (P1) in the first direction (Y); a plurality of first readers arranged in the second direction (X) and configured to optically read colors of first ranges in a plurality of first patterns (41 to 45) corresponding to digits except a least significant digit among the color patterns, respectively, the first ranges in the first patterns being arranged in the second direction (X); and a plurality of second readers (22a to 22c) arranged in the first direction (Y) and configured to optically read colors of second ranges (32a to 32c) in a plurality of second patterns (46a to 46h) arranged in the first direction (Y) corresponding to patterns of the least significant digit among the color patterns, respectively, the adjacent second readers being arranged in the first direction (Y) at an interval (P2) different from the width (P1) of the pattern in the first direction (Y), and one of the second readers being arranged in the second direction (X) side by side with the plurality of the first readers . <EOS>