Optical correction method for spectral calibration of hyperspectral imager

An optical correction method for spectral calibration of a hyperspectral imager, comprising:

• step 1:
• performing multiple measurements on a standard light source by using a hyperspectral imager, and acquiring measurement data for each measurement;
• obtaining, based on the measurement data, comparative deviation data, wherein the measurement data comprises measured values of wavelength points, and the comparative deviation data comprises comparative deviation degree values ZXj;
• if a comparative deviation degree value ZXj is greater than or equal to a comparative deviation degree threshold, generating a measurement abnormality signal;
• acquiring an abnormal signal occurrence proportion BJ;
• and generating, based on the abnormal signal occurrence proportion BJ, a suspected wavelength shift signal;
• step 2:
• acquiring, based on the generated suspected wavelength shift signal, a plurality of spectral curves obtained from the multiple measurements, and performing comparative analysis between each of the plurality of spectral curves and a standard spectral curve to obtain shift determination data, wherein the shift determination data comprises shift determination values CV;
• marking a measured spectral curve as an abnormal measured spectral curve based on a shift determination value CV;
• acquiring a quantity proportion value JK of abnormal measured spectral curves, and determining, based on the quantity proportion value JK of the abnormal measured spectral curves, whether wavelength has shifted;
• and generating a shift signal;
• step 3:
• acquiring, based on the shift signal, transmission time data of data points, wherein the transmission time data of the data points comprises transmission time points of the data points;
• analyzing transmission data of the data points to obtain data point transmission fluctuation parameters FG;
• and determining, based on the data point transmission fluctuation parameters FG, data point transmission stability during the measurements of the standard light source by the hyperspectral imager;
• arranging the data points sequentially according to the transmission time points, extracting interval time lengths between the data points, marking the interval time length with a highest frequency of occurrence as a reference time length, marking interval time periods, corresponding to interval time lengths that do not match the reference time length, as the target time periods;
• performing difference processing between the interval time lengths corresponding to all the target time periods and the reference time length separately, and summing absolute values of differences to obtain a time deviation value of the target time periods, the time deviation ratio of the target time periods is the ratio of the time deviation value of the target time periods and the reference time length;
• and
• step 4:
• acquiring a detection period corresponding to an abnormal measured spectral curve;
• performing comparative analysis between the detection period corresponding to the abnormal measured spectral curve and a target time period;
• classifying the abnormal measured spectral curve based on a comparative analysis result;
• analyzing the classified abnormal measured spectral curve to obtain a period overlap degree value AS;
• comparing the period overlap degree value AS with a period overlap degree threshold;
• and determining, based on a comparison result, whether a cause for the wavelength shift is poor data point transmission stability.