Particle size distribution measuring device and program for particle size distribution measuring device

A program for a particle size distribution measuring device that irradiates with light a particle group, which is a measurement target and which is accommodated in a cell, and that calculates a particle size distribution of the particle group on the basis of a light intensity signal indicating a light intensity of diffracted and/or scattered light resulting from the particle group, the program causing a computer to execute functions of:

• an actual spectrum obtaining unit that obtains an actual spectrum which is a light intensity spectrum obtained from the light intensity signal;
• a non-target spectrum calculating unit that receives non-target particle size distribution data indicating a particle size distribution of a non-target particle group, which is not the measurement target and which is accommodated in the cell, and that calculates, on the basis of the non-target particle size distribution data, a non-target spectrum which is a light intensity spectrum to be obtained by irradiating the non-target particle group with light;
• a non-target spectrum removing unit that calculates a target spectrum which is a light intensity spectrum obtained by subtracting the non-target spectrum from the actual spectrum;
• and
• a target particle size distribution calculating unit that calculates the particle size distribution of the particle group which is the measurement target on the basis of the target spectrum,
• wherein the non-target spectrum calculating unit calculates the non-target spectrum by using the non-target particle size distribution data and a refractive index of the non-target particle group.