Patent ID: 7256892

Claim:
A measuring instrument for measuring fluorescence intensity of fluorescence of each of a plurality of fluorescent coloring matters when a sample mixed with the plurality of fluorescent coloring matters having different excitation wavelengths and having numbers 1 to n given thereto is irradiated with light having different wavelengths, comprising: a light source unit capable of irradiating the sample with the light having the different wavelengths; a light receiving unit that receives fluorescence of the fluorescent coloring matters and outputs an electrical signal corresponding to a fluorescence intensity of the received fluorescence; a calculation section and a light amount monitor that detects a light amount of light emitted by the light source unit and outputs a signal to the calculation section, wherein the calculation section calculates the fluorescence intensity of the fluorescence of each of the fluorescent coloring matters emitted from the sample using a correction coefficient that is calculated based upon an output value X k of the electrical signal output by the light receiving unit when the light source unit irradiates each of a plurality of correction samples, each correction sample being mixed with one of the plurality of fluorescent coloring matters and the respective mixed fluorescent coloring matters being different from one another, with light having an excitation wavelength of a k-th fluorescent coloring matter (k=1, 2, . . . , n), assuming that a fluorescent intensity of the k-th fluorescent coloring matter is represented by Y k in the sample mixed with the plurality of fluorescent coloring matters, the correction coefficient is a matrix (a ij (i=1, 2, . . . , n; j=1, 2, . . . , n)) satisfying Expression (23): [ a 11 a 12 a 13 a 14 … a 1 ⁢ n a 21 a 22 a 23 a 24 … a 2 ⁢ n a 31 a 32 a 33 a 34 … a 3 ⁢ n a 41 a 42 a 43 a 44 … a 4 ⁢ n ⋮ ⋮ ⋮ ⋮ ⋮ ⋮ a n1 a n2 a n3 a n4 … a nn ] ⁡ [ Y 1 Y 2 Y 3 Y 4 ⋮ Y n ] = [ X 1 X 2 X 3 X 4 ⋮ X n ] ( 23 ) wherein the calculation section corrects the output values X 1 to X n or the matrix elements a 11 to a nn based on the signal output by the light amount monitor.