WO2022057174A1 - 一种用于光谱仪的线阵cmos数据处理方法 - Google Patents

一种用于光谱仪的线阵cmos数据处理方法 Download PDF

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WO2022057174A1
WO2022057174A1 PCT/CN2021/071641 CN2021071641W WO2022057174A1 WO 2022057174 A1 WO2022057174 A1 WO 2022057174A1 CN 2021071641 W CN2021071641 W CN 2021071641W WO 2022057174 A1 WO2022057174 A1 WO 2022057174A1
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刘召贵
朱杨强
袁辉
胡曦
李正建
李胜辉
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江苏天瑞仪器股份有限公司
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    • G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
    • G01N21/62—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light
    • G01N21/71—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited
    • G01N21/73—Systems in which the material investigated is excited whereby it emits light or causes a change in wavelength of the incident light thermally excited using plasma burners or torches

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  • the invention belongs to signal processing in the field of spectrometers, and in particular relates to a linear array CMOS data processing method for spectrometers.
  • ICP emission spectrometer is an inductively coupled plasma spectrometer.
  • ICP emission spectrometry is a method for analyzing the element to be tested based on the characteristic spectral lines emitted by the atoms of the element to be tested in the excited state when they return to the ground state.
  • ICP emission spectrometer is mainly used for inorganic elements.
  • Qualitative and quantitative analysis the current spectrometers on the market usually use CID for detection. Due to the expensive enhancement of CID, the cost of the spectrometer is high.
  • low-cost linear CMOS can be used instead of CID, but the linear CMOS itself has dark current. The fluctuation is large and the background fluctuation is obvious, which leads to a high detection limit of the spectrometer, and the stability and repeatability of the instrument are poor, which has a great impact on the spectrometer.
  • the technical problem to be solved by the present invention is to provide a linear array CMOS data processing method which reduces the influence of background fluctuation on the spectrometer.
  • CMOS data processing method for a spectrometer the method is:
  • step S5 subtract the intensity data of pure water from the intensity data of the element to be tested collected in step S4 to obtain several intensity values of the element to be tested corresponding to different concentrations;
  • step S6 according to the calculation in step S5, the intensity value of the element to be measured is obtained, and several net intensity values of the element to be measured are calculated and determined;
  • S8 Collect the strength data of the unknown sample and subtract the strength data of pure water to obtain the strength value of the unknown sample, and calculate and determine the net strength value of the unknown sample according to the strength value;
  • step S9 Bring the net intensity value obtained in step S8 into the linear function obtained in step S7 to obtain the content of the element to be measured in the unknown sample.
  • the method for determining the net intensity value is as follows: the intensity data includes the peak intensity and the left and right background intensities, select n minimum values from the left and right background intensities to obtain the minimum average intensity value, and then subtract the peak intensity from the peak intensity. The smallest average intensity value yields the net intensity value.
  • n 2.
  • n 10.
  • the primary functions obtained in the steps S2 to S7 have been pre-stored in the database, and are directly called when the unknown sample is detected.
  • the different concentration gradients in the step S2 are 0.2 ppm, 0.5 ppm, 1 ppm, 2.5 ppm, and 5 ppm.
  • the different concentration gradients in the step S2 are 0.25 ppm, 0.5 ppm, 1 ppm, 2 ppm, and 5 ppm.
  • the beneficial effects of the present invention are: by using the above processing method for linear array CMOS data, the impact of background fluctuation on the spectrometer can be effectively reduced, the detection limit of the instrument is greatly reduced, and the stability and repeatability of the instrument are improved. It can test some difficult-to-excite elements, broaden the application field of the spectrometer, and reduce the production cost of the instrument.
  • FIG. 1 is a flow chart of a linear array CMOS data processing method for a spectrometer according to the present invention.
  • CMOS data processing method for a spectrometer is as follows:
  • concentration gradient needs to include the concentration of the sample at the location. 1ppm, 2.5ppm, 5ppm or 0.2ppm, 0.5ppm, 1ppm, 2.5ppm, 5ppm.
  • step S5 Subtract the intensity data of pure water from the intensity data of the element to be tested collected in step S4, that is, the peak intensity of the element to be measured displayed on the spectrum and the left and right background intensities minus the peak intensity of pure water displayed on the spectrum With the left and right background intensities, minus the interference of the element to be measured by pure water, several peak intensity values and left and right background intensity values of the element to be measured corresponding to different concentrations are obtained.
  • step S6 According to the calculation in step S5, the intensity value of the element to be measured is obtained, and several net intensity values of the element to be measured are calculated and determined; the method for determining the net intensity value is to select n minimum values from the left and right background intensity values to obtain the minimum average Intensity value, then the net intensity value is obtained by subtracting the minimum average intensity value from the peak intensity value; where n>2, n is selected according to needs and through experience, and is selected as 10 in this scheme.
  • step S7 Fit the net intensity value of the element to be measured in step S6 with the content of the element to be measured as a linear function, and the content of the element to be measured is known because the standard solution is used for the element to be measured.
  • the element to be measured is selected as required, and fitted into a linear function of a plurality of different elements, which can be prepared in advance and stored in the spectrometer, and can be called during use.
  • step S8 Collect the strength data of the unknown sample and subtract the strength data of pure water to obtain the strength value of the unknown sample, and calculate and determine the net strength value of the unknown sample according to the strength value; the method for calculating the net strength value of the unknown sample in this step is the same as step S5 Same as step S6.
  • step S9 Bring the net intensity value obtained in step S8 into the linear function obtained in step S7 to obtain the content of the element to be measured in the unknown sample.
  • the Pb element is tested by the above method, and 5 groups of test results are evaluated. 10 samples are selected for testing in each group.
  • the concentration gradient of the single standard solution of the element to be tested is 0.2ppm, 0.5ppm, 1ppm, 2.5ppm, 5ppm.
  • the relative standard deviations obtained after using the method of this scheme are all smaller than those obtained before using the method of this scheme, which indicates that after using the method of this scheme
  • the obtained results are more accurate, effectively reduce the impact of background fluctuations on the spectrometer, greatly reduce the detection limit of the instrument, improve the stability and repeatability of the instrument, and can test some difficult-to-excite elements, broadening the The field of use of the spectrometer, while reducing the production cost of the instrument.

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Abstract

一种用于光谱仪的线阵CMOS数据处理方法，包括：开启光谱仪(S1)；选取不同浓度梯度的待测元素的单标溶液形成谱图(S2)；确定待测元素的峰位置与左右背景位置(S3)；采集纯水的强度数据以及采集待测元素若干不同浓度的强度数据(S4)；得到待测元素的强度值(S5)；计算待测元素的净强度值(S6)；将净强度值与待测元素的含量拟合为一次函数(S7)；确定未知样品的净强度值(S8)；求得未知样品中待测元素的含量(S9)。该方法能有效降低本底波动对光谱仪产生的影响和仪器的检出限，提升了仪器的稳定性以及重复性，可以测试较难激发的元素。

Description

一种用于光谱仪的线阵CMOS数据处理方法
本申请要求了申请日为2020年09月16日，申请号为CN202010971679.4，发明名称为“一种用于光谱仪的线阵CMOS数据处理方法”的发明专利申请的优先权，其全部内容通过引用结合在本申请中。
技术领域
本发明属于光谱仪领域中信号处理，尤其是涉及一种用于光谱仪的线阵CMOS数据处理方法。
背景技术
ICP发射光谱仪即电感耦合等离子体光谱仪，ICP发射光谱法是根据处于激发态的待测元素原子回到基态时发射的特征谱线对待测元素进行分析的方法，ICP发射光谱仪主要应用于无机元素的定性及定量分析，目前市场上的光谱仪通常采用CID进行检测，由于CID的加强昂贵，导致光谱仪的成本较高，为了节约成本可以采用价格低廉的线阵CMOS替代CID，但是线阵CMOS本身暗电流波动较大，本底波动明显，从而导致光谱仪的检出限较高，仪器的稳定性与重复性较差，对光谱仪产生较大影响。
发明内容
本发明所要解决的技术问题是提供一种降低本底波动对光谱仪的影响的线阵CMOS数据处理方法。
本发明解决其技术问题所采取的技术方案是：一种用于光谱仪的线阵CMOS数据处理方法，该方法为，
S1、开启光谱仪进行预热；
S2、选取不同浓度梯度的待测元素的单标溶液，通过光谱仪形成若干谱图；
S3、根据谱图确定对应浓度梯度的待测元素的峰位置与左右背景位置；
S4、采集纯水的强度数据以及采集待测元素若干不同浓度的强度数据；
S5、将步骤S4中采集的待测元素的强度数据减去纯水的强度数据，得到若干对应不同浓度的待测元素的强度值；
S6、根据步骤S5中计算得到待测元素强度值，计算确定待测元素的若干个净强度值；
S7、将步骤S6中的待测元素的净强度值与待测元素的含量拟合为一次函数；
S8、采集未知样品的强度数据并减去纯水的强度数据得到未知样品的强度值，根据该强度值计算确定未知样品的净强度值；
S9、将步骤S8中得到的净强度值带入至步骤S7中得到的一次函数，求得未知样品中待测元素的含量。
进一步具体的，所述的净强度值的确定方法为，强度数据包括峰强度以及左右背景强度，在左右背景强度中选取n个最小值求得其最小平均强度值，之后通过峰强度减去该最小平均强度值得到净强度值。
进一步具体的，所述的n＞2。
进一步具体的，所述的n＝10。
进一步具体的，所述的步骤S2-步骤S7得到的一次函数已经预存入数据库内，在检测未知样品时直接调用。
进一步具体的，所述的步骤S2中不同浓度梯度为0.2ppm、0.5ppm、1ppm、2.5ppm、5ppm。
进一步具体的，所述的步骤S2中不同浓度梯度为0.25ppm、0.5ppm、1ppm、2ppm、5ppm。
本发明的有益效果是：通过采用上述针对线阵CMOS数据的处理方法，可以有效降低本底波动对光谱仪产生的影响，极大的降低了仪器的检出限，提升了仪器的稳定性以及重复性，进而可以测试一些较难激发的元素，拓宽了光谱仪的使用领域，同时降低了仪器的生产成本。
附图说明
图1是本发明用于光谱仪的线阵CMOS数据处理方法的流程图。
具体实施方式
下面结合附图和具体实施方式对本发明进行详细描述。
如图1所示一种用于光谱仪的线阵CMOS数据处理方法，该方法为，
S1、开启光谱仪进行预热，预热2小时；
S2、选取不同浓度梯度的待测元素的单标溶液，通过光谱仪形成若干谱图，不同浓度梯度需要根据需求进行选择，该浓度梯度需要包括位置样品的浓度，一般选择为0.2ppm、0.5ppm、1ppm、2.5ppm、5ppm或者0.2ppm、0.5ppm、1ppm、2.5ppm、5ppm。
S3、根据谱图确定对应浓度梯度的待测元素的峰位置与左右背景位置，在谱图中确定元素的位置从而能够确定该元素。
S4、采集纯水的强度数据以及采集待测元素若干不同浓度的强度数据，该强度数据包括在谱图上显示的峰强度以及左右背景强度。
S5、将步骤S4中采集的待测元素的强度数据减去纯水的强度数据，即待测元素在谱图上显示的峰强度与左右背景强度减去纯水在谱图上显示的峰强度与左右背景强度，减去纯水对待测元 素的干扰，得到若干对应不同浓度的待测元素的峰强度值与左右背景强度值。
S6、根据步骤S5中计算得到待测元素强度值，计算确定待测元素的若干个净强度值；净强度值的确定方法为，在左右背景强度值中选取n个最小值求得其最小平均强度值，之后通过峰强度值减去该最小平均强度值得到净强度值；其中n＞2，n根据需要并通过经验进行选取，在本方案中选取为10。
S7、将步骤S6中的待测元素的净强度值与待测元素的含量拟合为一次函数，而待测元素因为采用的为标准溶液，故待测元素的含量为已知。
上述步骤中，待测元素根据需要选择，拟合成为多个不同元素的一次函数，可以预先准备好后存储于光谱仪内部，在使用时调用即可。
S8、采集未知样品的强度数据并减去纯水的强度数据得到未知样品的强度值，根据该强度值计算确定未知样品的净强度值；该步骤计算未知样品的净强度值的方法与步骤S5与步骤S6一致。
S9、将步骤S8中得到的净强度值带入至步骤S7中得到的一次函数，求得未知样品中待测元素的含量。
下面通过上述方法对Pb元素进行测试，对5组测试结果进行评估，每组中选取10个样品进行测试，待测元素的单标溶液的浓度梯度为0.2ppm、0.5ppm、1ppm、2.5ppm、5ppm。
表1：5组实施例的对比表
Figure PCTCN2021071641-appb-000001
Figure PCTCN2021071641-appb-000002
如表1中所示，在实施例1、2、3、4以及5中使用本方案方法后得到的相对标准偏差均小于使用本方案方法前得到的相对标准偏差，这说明使用本方案方法后所得的结果更加准确，有效降低本底波动对光谱仪产生的影响，极大的降低了仪器的检出限，提升了仪器的稳定性以及重复性，进而可以测试一些较难激发的元素，拓宽了光谱仪的使用领域，同时降低了仪器的生产成本。
需要强调的是：以上仅是本发明的较佳实施例而已，并非对本发明作任何形式上的限制，凡 是依据本发明的技术实质对以上实施例所作的任何简单修改、等同变化与修饰，均仍属于本发明技术方案的范围内。

Claims (7)

  1. 一种用于光谱仪的线阵CMOS数据处理方法，其特征在于，该方法为，
    S1、开启光谱仪进行预热；
    S2、选取不同浓度梯度的待测元素的单标溶液，通过光谱仪形成若干谱图；
    S3、根据谱图确定对应浓度梯度的待测元素的峰位置与左右背景位置；
    S4、采集纯水的强度数据以及采集待测元素若干不同浓度的强度数据；
    S5、将步骤S4中采集的待测元素的强度数据减去纯水的强度数据，得到若干对应不同浓度的待测元素的强度值；
    S6、根据步骤S5中计算得到待测元素强度值，计算确定待测元素的若干个净强度值；
    S7、将步骤S6中的待测元素的净强度值与待测元素的含量拟合为一次函数；
    S8、采集未知样品的强度数据并减去纯水的强度数据得到未知样品的强度值，根据该强度值计算确定未知样品的净强度值；
    S9、将步骤S8中得到的净强度值带入至步骤S7中得到的一次函数，求得未知样品中待测元素的含量。
  2. 根据权利要求1所述的用于光谱仪的线阵CMOS数据处理方法，其特征在于，所述的净强度值的确定方法为，强度数据包括峰强度以及左右背景强度，在左右背景强度中选取n个最小值求得其最小平均强度值，之后通过峰强度减去该最小平均强度值得到净强度值。
  3. 根据权利要求2所述的用于光谱仪的线阵CMOS数据处理方法，其特征在于，所述的n＞2。
  4. 根据权利要求3所述的用于光谱仪的线阵COMS数据处理方法，其特征在于，所述的n＝10。
  5. 根据权利要求1所述的用于光谱仪的线阵COMS数据处理方法，其特征在于，所述的步骤S2-步骤S7得到的一次函数已经预存入数据库内，在检测未知样品时直接调用。
  6. 根据权利要求1所述的用于光谱仪的线阵COMS数据处理方法，其特征在于，所述的步骤S2中不同浓度梯度为0.2ppm、0.5ppm、1ppm、2.5ppm、5ppm。
  7. 根据权利要求1所述的用于光谱仪的线阵COMS数据处理方法，其特征在于，所述的步骤S2中不同浓度梯度为0.25ppm、0.5ppm、1ppm、2ppm、5ppm。
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