Material property measuring apparatus

A material property measuring apparatus comprising:

• a radiation source irradiator configured to irradiate a measurement target material with radiation beams having n different wavelengths;
• a detector configured to detect intensities of radiation beams having the respective wavelengths after the irradiation of the measurement target material;
• and
• a processing unit configured to correct the detected intensity of the radiation beam having at least a part of the respective wavelengths using a correction coefficient in which rows and columns are respectively represented by a matrix of an order of n or less, and to calculate an index value indicating a property of the measurement target material on the basis of relative intensities of the radiation beams having the respective wavelengths after the correction, wherein
• the processing unit converts the calculated index value into a property value by referring to a calibration curve which correlates the index value with the property value, after the calculation of the index value;
• and
• the correction coefficient is determined so that the degree of coincidence between calibration curves for a plurality of kinds of the measurement target material satisfies a certain criterion.