Differential refractive index measurement method, measurement device, and measurement program

A measurement device of a differential refractive index comprising:

• a detection part for the differential refractive index having a sample cell that a sample liquid passes through, a reference cell that a reference liquid passes through, and a light detector that detects a change in direction of travel of light that sequentially transmitted through the two cells;
• a sample pump that sends a solvent to the sample cell;
• a sample injection part that is provided on a channel from the sample pump to the sample cell and injects a sample to the solvent sent from the sample pump to form the sample liquid;
• a reference pump that sends the solvent to the reference cell as the reference liquid;
• and
• a control device,
• for measuring the differential refractive index between the sample liquid and the reference liquid based on an output signal of the light detector, wherein
• the control device comprises:
• an adjustment-value determiner that determines an adjustment value of a phase difference between the sample pump and the reference pump based on noise waveform informations that occur in the output signal of the light detector, according to a difference in lengths of channels of the sample liquid and the reference liquid or a difference in devices connected to the channels of the sample liquid and the reference liquid;
• and
• a phase-difference adjuster that adjusts the phase difference between the sample pump and the reference pump so that a noise that occurs in the output signal of the light detector by propagation of pulsation from the sample pump within the sample cell and a noise that occurs in the output signal of the light detector by propagation of pulsation from the reference pump within the reference cell cancel each other.

A non-transitory computer-readable storage medium that stores a measurement program of a differential refractive index that makes a computer function to:

• drive of a sample pump to send a sample liquid to a sample cell;
• drive of a reference pump to send a reference liquid to a reference cell;
• and
• acquire an output signal of a light detector that detects light sequentially transmitted through the sample cell and the reference cell, wherein the measurement program that-further makes the computer function to:
• determine an adjustment value of a phase difference between the sample pump and the reference pump based on noise waveform informations that occur in the output signal of the light detector, according to a difference in lengths of channels of the sample liquid and the reference liquid or a difference in devices connected to the channels of the sample liquid and the reference liquid;
• and
• adjust the phase difference between the sample pump and the reference pump before starting measurement of the differential refractive index, so that a noise that occurs in the output signal of the light detector by propagation of pulsation from the sample pump within the sample cell and a noise that occurs in the output signal of the light detector by propagation of pulsation from the reference pump within the reference cell cancel each other.