Element detection method

Abstract

The present invention provides an element detection method. In the excitation stage, the sample to be tested is excited to emit complex light with characteristic wavelengths corresponding to each element. The spectroscopic stage is as follows: the complex light is spectroscopically split by a grating so that each wavelength of light in the complex light is separated in the first direction, and then the spectroscopically split by a prism so that each level of diffracted light is separated in the second direction. The surface array detector outputs a two-dimensional spectrum, and the two-dimensional spectrum includes a plurality of light spots distributed in the first direction and the second direction respectively. The analysis stage is as follows: a coordinate system is established in the two-dimensional spectrum, the horizontal axis is the first direction, the vertical axis is the second direction, and the grating equation is used to obtain the wavelength distribution corresponding to the surface array detector pixels in the first direction, and the distribution of the diffraction order in the second direction is obtained, thereby obtaining the corresponding relationship between the characteristic wavelength and the light intensity in each diffraction order. The present invention has the advantages of small amount of calculation and fast spectrum acquisition.

Description

Technical Field

[0001] The present invention relates to element detection, and in particular to an element detection method. Background Art

[0002] In element detection, ICP-OES technology is usually used. This technology is to use a medium-step dispersion system and a cross-dispersion form to form a two-dimensional spectrum on the image plane. In the data processing process, accurate positioning of the signal spot and precise calibration of the wavelength are key technologies. The traditional positioning algorithm is a calculation method to obtain the centroid of the spectrum, calculate the order and wavelength of the characteristic spectrum line, and achieve positioning. In the calculation process, the positioning accuracy of the signal spot, the large amount of data and the complex calculation will increase the calculation time and affect the efficiency of the instrument. Summary of the invention

[0003] In order to solve the deficiencies in the above-mentioned prior art solutions, the present invention provides an element detection method.

[0004] The objective of the present invention is achieved through the following technical solutions:

[0005] Element detection method, element detection method, the element detection method includes an excitation stage, a spectroscopic stage and an analysis stage. In the excitation stage, the sample to be tested is excited to emit complex light with characteristic wavelengths corresponding to each element; the spectroscopic stage is:

[0006] The polychromatic light is split by a grating so that each wavelength of light in the polychromatic light is separated in a first direction, and then split by a prism so that each level of diffracted light is separated in a second direction, and the area array detector outputs a two-dimensional spectrum, and the two-dimensional spectrum includes a plurality of light spots distributed in the first direction and the second direction; the angle between the first direction and the second direction is a right angle or an acute angle;

[0007] The analysis stage is to establish a coordinate system in the two-dimensional spectrum, with the horizontal axis being the first direction and the vertical axis being the second direction, and to use the grating equation to obtain the wavelength distribution corresponding to the pixels of the array detector in the first direction; the processing method for the light spot is to find the coordinates (x m ,y m ), y0=[y m ];

[0008] Under the condition of y0, find the m The closest valid point with integer coordinates x0, to y m Round up and down to get y ceil ,y floor ;

[0009] Get the coordinates (x m ,ym ) corresponds to the wavelength ,λ ceil is the coordinate (x0,y ceil ) corresponds to the wavelength, λ floor is the coordinate (x0,y floor ) corresponds to the wavelength, coordinate (x0,y ceil ) and (x0,y floor ) respectively correspond to the pixels of the array detector;

[0010] The distribution of the diffraction orders in the second direction is obtained, so as to obtain the corresponding relationship between the wavelength and the light intensity in each diffraction order.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] The present invention utilizes a spectrum restoration algorithm to convert a two-dimensional spectrum dispersed by a spectroscopic system and collected by a planar array detector into a one-dimensional spectrum corresponding to wavelength and light intensity, and simultaneously adopts a band splicing method to perform fast, accurate, and intuitive spectral line positioning, fundamentally solving the problems of complex and time-consuming data calculation of two-dimensional spectra. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The disclosure of the present invention will become easier to understand with reference to the accompanying drawings. It is easy for those skilled in the art to understand that these drawings are only used to illustrate the technical solution of the present invention and are not intended to limit the scope of protection of the present invention. In the drawings:

[0014] Figure 1 is a schematic diagram of a two-dimensional spectrum according to an embodiment of the present invention;

[0015] Figure 2 is a schematic diagram of a one-dimensional spectrum according to an embodiment of the present invention. DETAILED DESCRIPTION

[0016] Figure 1-2 The following description describes the optional embodiments of the present invention to teach those skilled in the art how to implement and reproduce the present invention. In order to teach the technical solution of the present invention, some conventional aspects have been simplified or omitted. It should be understood by those skilled in the art that variations or substitutions derived from these embodiments will be within the scope of the present invention. It should be understood by those skilled in the art that the following features can be combined in various ways to form multiple variations of the present invention. Thus, the present invention is not limited to the following optional embodiments, but is only limited by the claims and their equivalents.

[0017] Example 1.

[0018] The element detection method of the embodiment of the present invention comprises:

[0019] An excitation stage, in which the sample to be tested is excited to emit complex-color light with characteristic wavelengths corresponding to each element;

[0020] In the spectroscopic stage, the complex light is split by a grating so that each wavelength of light in the complex light is separated in the first direction, and then split by a prism so that each level of diffracted light is separated in the second direction. The array detector outputs a two-dimensional spectrum, such as Figure 1 As shown, the two-dimensional spectrum includes a plurality of light spots distributed in a first direction and a second direction; the angle between the first direction and the second direction is a right angle or an acute angle;

[0021] In the analysis phase, a coordinate system is established in the two-dimensional spectrum, with the horizontal axis being the first direction and the vertical axis being the second direction, and the wavelength distribution corresponding to the pixels of the array detector in the first direction is obtained by using the grating equation; the light spot is processed by finding the coordinates (x m ,y m ), y0=[y m ]; that is, y0 is rounded;

[0022] Under the condition of y0, find the m The closest valid point with integer coordinates x0, to y m Round up and down to get y ceil ,y floor ;

[0023] Get the coordinates (x m ,y m ) corresponds to the wavelength ,λ ceil is the coordinate (x0,y ceil ) corresponds to the wavelength, λ floor is the coordinate (x0,y floor ) corresponds to the wavelength, coordinate (x0,y ceil ) and (x0,y floor ) respectively correspond to the pixels of the array detector;

[0024] The distribution of the diffraction orders in the second direction is obtained, so as to obtain the corresponding relationship between the wavelength and the light intensity in each diffraction order, such as Figure 2 shown.

[0025] Example 2.

[0026] An application example of the element detection method according to embodiment 1 of the present invention.

[0027] In this application example, the element detection method of the embodiment of the present invention includes:

[0028] In the excitation stage, the sample to be tested is excited by using ICP-OES technology, and the excitation point emits complex color light with characteristic wavelengths corresponding to each element;

[0029] In the spectroscopic stage, the complex light is split by the echelle grating so that the wavelengths of light in the complex light are separated in the first direction, and then split by the prism so that the diffracted light of each level is separated in the second direction. The area array CCD detector outputs a two-dimensional spectrum, such as Figure 1 As shown, the two-dimensional spectrum includes a plurality of light spots distributed in a first direction and a second direction, that is, each diffraction order has a plurality of light spots; the angle between the first direction and the second direction is a right angle;

[0030] In the analysis stage, a coordinate system is established in the two-dimensional spectrum, with the horizontal axis being the first direction and the vertical axis being the second direction, and the grating equation is used to obtain the wavelength distribution corresponding to the array detector pixels in the first direction, that is, the positions with integer coordinates in the horizontal axis direction correspond to the detector pixels, and the wavelength of the positions can be obtained according to the diffraction equation, but the wavelength corresponding to the positions with non-integer coordinates in the horizontal axis direction is unknown. In view of this, it is necessary to process the light spots (each light spot corresponds to the intensity of the characteristic spectrum line of an element), and the specific method is as follows:

[0031] Find the coordinates (x m ,y m ), y0=[y m ];

[0032] Under the condition of y0, find the m The closest valid point with integer coordinates x0, to y m Round up and down to get y ceil ,y floor ;

[0033] Get the coordinates (x m ,y m ) corresponds to the wavelength , that is, the wavelength of the characteristic spectrum corresponding to the spot, λ ceil is the coordinate (x0,y ceil ) corresponds to the wavelength, λ floor is the coordinate (x0,y floor ) corresponds to the wavelength, coordinate (x0,y ceil ) and (x0,y floor ) correspond to the pixels of the array detector respectively

[0034] The distribution of the diffraction orders in the second direction is obtained, so as to obtain the wavelength corresponding to each light spot in each diffraction order, that is, to obtain the corresponding relationship between the wavelength and the light intensity, such as Figure 2 shown.

Claims

1. An element detection method, comprising an excitation stage, a spectroscopic stage and an analysis stage. In the excitation stage, the sample to be tested is excited to emit complex light with characteristic wavelengths corresponding to each element; characterized in that: The light splitting stage is: The polychromatic light is split by a grating so that each wavelength of light in the polychromatic light is separated in a first direction, and then split by a prism so that each level of diffracted light is separated in a second direction, and the area array detector outputs a two-dimensional spectrum, and the two-dimensional spectrum includes a plurality of light spots distributed in the first direction and the second direction; the angle between the first direction and the second direction is a right angle or an acute angle; The analysis stage is to establish a coordinate system in the two-dimensional spectrum, with the horizontal axis being the first direction and the vertical axis being the second direction, and to use the grating equation to obtain the wavelength distribution corresponding to the pixels of the array detector in the first direction; the processing method for the light spot is to find the coordinates (x m ,y m ), y0=[y m ]; Under the condition of y0, find the m The closest valid point with integer coordinates x0, to y m Round up and down to get y ceil ,y floor ; Get the coordinates (x m ,y m ) corresponds to the wavelength ,y ceil is the coordinate (x0,y ceil ) corresponds to the wavelength, λ floor is the coordinate (x0,y floor ) corresponds to the wavelength, coordinate (x0,y ceil ) and (x0,y floor ) respectively correspond to the pixels of the array detector; The distribution of the diffraction orders in the second direction is obtained, so as to obtain the corresponding relationship between the wavelength and the light intensity in each diffraction order.

2. The element detection method according to claim 1, characterized in that: The sample to be tested is excited by ICP-OES technology.

3. The element detection method according to claim 1, characterized in that: The area array detector adopts CCD or CMOS.

4. The element detection method according to claim 1, characterized in that: The grating is an echelle grating.

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