Automatic analyzer and program

An automatic analyzer comprising:

• a container, the container containing a liquid;
• a dispensing unit that has a dispensing probe and is configured to move a tip portion of the dispensing probe to a liquid level of the liquid in the container and suck and discharge the liquid;
• a housing;
• an oscillation circuit connected to the dispensing probe, the oscillation circuit configured to output an alternating current (AC) signal of an oscillation frequency according to a capacitance between the tip of the dispensing probe and a ground of the housing;
• a detector configured to receive the AC signal of the oscillation frequency output by the oscillation circuit and detect whether the tip of the dispensing probe has come into contact with the liquid level in the container based on the oscillation frequency of the AC signal output from the oscillation circuit;
• a first processing unit comprising a first controller configured to control an operation of the dispensing unit based on a detection result of the detector;
• a feature amount value extraction unit configured to divide time-series data of the oscillation frequency of the AC signal output by the oscillation circuit into a plurality of sections until a certain time elapses after the dispensing probe starts to be lowered for each section of the plurality of sections, extract a feature amount value for each section of the plurality of sections, and output the extracted feature amount value as a data series;
• a bubble contact determination processing unit configured to compute a correlation between a waveform of the data series of the feature amount value output from the feature amount value extraction unit and a waveform model based on a waveform observed when the tip of the dispensing probe comes into contact with a bubble on the liquid level in the container, and determine whether liquid level detection has been performed one way based on a result of computing the correlation;
• and
• a second processing unit comprising a second controller configured to determine a deviation between the tip of the dispensing probe and the liquid level in the container and a factor of the deviation based on a determination result of the bubble contact determination processing unit;
• wherein
• the feature amount value is a first value and/or second value for each section of the plurality of sections;
• the waveform model corresponds to a trapezoidal waveform having continuous peak values in a section of the plurality of sections corresponding to a number of milliseconds;
• a waveform of a data series of the feature amount value for which a correlation with the waveform model is computed is the waveform of the data series in which a feature amount value extracted by the feature amount value extraction unit before the detector determines that the tip of the dispensing probe has come into contact with the liquid level in the container is deleted from the data series of the feature amount value.