WO2019119274A1

WO2019119274A1 - Spectrometer and spectrum detecting apparatus

Info

Publication number: WO2019119274A1
Application number: PCT/CN2017/117259
Authority: WO
Inventors: 牟涛涛
Original assignee: 深圳达闼科技控股有限公司
Priority date: 2017-12-19
Filing date: 2017-12-19
Publication date: 2019-06-27
Also published as: CN108235729A

Abstract

A spectrometer comprises a spatial filter device (31), a spectroscopic device (32), a collimating assembly (33) provided on a light wave input optical path of the spectroscopic device, and a focusing assembly (34) and a sensor (35) provided on a light wave output optical path of the spectroscopic device. The collimating assembly is provided between the spatial filter device and the spectroscopic device. The focusing assembly is provided between the spectroscopic device and the sensor. The collimating assembly is used to adjust, in a first focal length range, a focal length of light waves on the light wave input optical path of the spectroscopic device; and/or, the focusing assembly is further used to adjust, in a second focal length range, the focal length of light waves on the light wave output optical path of the spectroscopic device. The invention also discloses a spectrum detecting apparatus. The spectrometer and the spectrum detecting apparatus relating to substance detection technology have a smaller size when compared with the prior art, thereby facilitating miniaturization of the spectrometer. The invention achieves the same or higher sensitivity than that of the prior art, and an improvement in spectral resolution and spectral measurement range.

Description

Spectrometer and spectrum detecting device

Technical field

Embodiments of the present invention relate to material detection techniques, and more particularly to a spectrometer and a spectrum detection apparatus.

Background technique

Current spectrum detection equipment usually consists of a probe and a spectrometer. The spectrometer is basically formed based on a reflective structure or a transmission structure of a common lens group (lens). The principle of the spectrometer based on the reflection structure is as follows: the spectrometer spatially transmits the light transmitted by the probe. After filtering, the following processing is performed. The collimating mirror collimates the light and then enters the grating to split the light. The focusing mirror focuses the spectrum of the grating separately onto the sensor surface. The principle of the spectrometer based on the common lens group (lens) structure is as follows: Spectrometer pair The light transmitted by the probe is spatially filtered and then processed as follows. The collimating transmission lens (lens) collimates the light and then enters the grating for splitting, and the focusing lens group (lens) focuses the spectrally separated spectrum onto the sensor surface.

For the reflective structure spectrometer, the main optimization parameters in the whole spectrum instrument are the curvature and angle of the mirror, the angle of the grating and other five parameters, and the variables are too few. In order to correct the aberration, only the light energy can be sacrificed, and the F number is increased. The F-number of the reflective spectrometer is F/4. The problems caused by the reflective spectrometer are: the adjustment mechanism is complicated, the optical path is crossed or there is a shared space, and the modular design is not convenient, resulting in the volume and weight cannot be reduced; in addition, the focal length of the mirror is not well adjusted. , resulting in low production efficiency; less optimization variables, can not effectively correct aberrations, it is not easy to improve resolution; F number is large, light energy is small, spectrometer sensitivity is low, detection speed is slow.

For the transmissive ordinary lens group/lens, the focal length of the lens group/lens is smaller than the length of the entire lens barrel. Due to the volume limitation of the spectrometer, the focal length selected by the lens is small, resulting in low resolution and insufficient utilization of the sensor surface.

In summary, the prior art is not conducive to the miniaturization of the spectrometer, and the sensitivity, spectral resolution, and spectral measurement range of the spectrometer are severely limited by volume.

Summary of the invention

Embodiments of the present invention provide a spectrometer and a spectrum detecting device, which are more advantageous for miniaturization of a spectrometer, and further, compared with the prior art, a smaller volume can obtain the same or higher sensitivity as the prior art, and at the same time improve Spectral resolution and spectral measurement range.

In a first aspect, a spectrometer is provided, comprising:

a spatial filter device, a beam splitting device, a collimating component disposed on the optical wave input optical path of the spectroscopic device, and a focusing component and a sensor disposed on the optical wave output optical path of the spectroscopic device; wherein the collimating component is disposed on Between the spatial filter device and the light splitting device, the focusing component is disposed between the light splitting device and the sensor; the spatial filter component is configured to spatially filter light waves output by the probe and to perform predetermined scattering An angle is emitted; the collimating component is configured to collimate and output the light wave outputted by the spatial filter; and the beam splitting component is configured to diffract the light wave outputted by the collimating component according to a wavelength, and output The focusing component is configured to focus and split the light wave output by the beam splitting component, and output the light wave output by the focusing component, and generate a corresponding spectrum; wherein the collimating component further For adjusting the focal length of the light wave on the incident light path of the light splitting device in the first focal length range, the incident surface of the collimating component The distance between the faces is less than the minimum system focal length of the collimating assembly; and/or the focusing assembly is further configured to adjust a focal length of light waves on the light exiting light path of the beam splitting device over a second focal length range, The distance between the entrance face and the exit face of the focus assembly is less than the minimum system focal length of the focus assembly.

In a second aspect, a spectral detecting apparatus includes: a probe and any of the above spectrometers; the probe is configured to emit a light wave to the detected sample, and receive a reflected light wave of the detected sample, and emit the reflected light wave to The spectrometer.

In the above solution, the spectrometer includes a spatial filter device, a beam splitting device, a collimating component disposed on the optical wave input optical path of the spectroscopic device, and a focusing component and a sensor disposed on the optical wave output optical path of the spectroscopic device; wherein a collimating component is disposed between the spatial filter component and the spectroscopic device, the focusing component is disposed between the spectroscopic device and the sensor; the spatial filter component is capable of spatially filtering the optical wave output by the probe and emitting at a predetermined scattering angle; the collimating component can The light wave outputted by the spatial filter is collimated and output; the light splitting component can illuminate the light wave outputted by the straight component according to the wavelength, and output; the focusing component can focus and output the light wave outputted by the collimating component; the sensor can receive Focusing on the light wave output by the component and generating a corresponding spectrum; in addition, the collimating component is further configured to adjust a focal length of the light wave on the incident light path of the light splitting device in the first focal length range, between the incident surface and the exit surface of the collimating component The distance is less than the minimum system focal length of the collimating component; and/or, the focus group Also used to adjust the focal length of the light wave on the light exiting light path of the light splitting device in the second focal length range, the distance between the incident surface and the exit surface of the focusing component is smaller than the minimum system focal length of the focusing component; thus, due to the incident surface of the collimating component The distance from the exit surface is smaller than the minimum system focal length of the collimating assembly and/or the distance between the incident surface and the exit surface of the focusing assembly is smaller than the minimum system focal length of the focusing assembly, so that the miniaturization of the spectrometer is more advantageous, and Compared to the technology, a smaller volume can achieve the same or higher sensitivity than the prior art, while improving spectral resolution and spectral measurement range.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description are only some of the present invention. For the embodiments, those skilled in the art can obtain other drawings according to the drawings without any creative work.

1 is a structural diagram of a spectrum detecting apparatus according to an embodiment of the present invention;

2 is a structural diagram of a spectrum detecting apparatus according to another embodiment of the present invention;

3 is a structural diagram of a spectrometer according to an embodiment of the present invention;

FIG. 4 is a schematic diagram of a structure of a spectrometer according to another embodiment of the present invention.

Detailed ways

It should be noted that, in the embodiments of the present invention, the words "exemplary" or "such as" are used to mean an example, an illustration, or a description. Any embodiment or design described as "exemplary" or "for example" in the embodiments of the invention should not be construed as preferred or advantageous over other embodiments or designs. Rather, the use of the words "exemplary" or "such as" is intended to present the concepts in a particular manner.

It should be noted that, in the embodiment of the present invention, "(English: of)", "corresponding (English: corresponding, relatent)" and "corresponding" may sometimes be mixed. It should be noted that When the difference is not emphasized, the meaning to be expressed is the same. "A and/or B" provided by the embodiments of the present application should be understood to include three cases of "A" alone, "B" alone, and "A and B".

Embodiments of the present invention provide a spectral detecting apparatus, as shown in FIG. 1, comprising: a probe 11 and a spectrometer 12. The probe 11 is for emitting a light wave to the detected sample 13 and receiving the reflected light wave of the detected sample 13 and emitting the reflected light wave to the spectrometer 12. The spectral detecting device provided by the embodiment of the present invention may be one of a Raman spectroscopy detecting device, an infrared spectroscopy detecting device, a fluorescence spectroscopy detecting device, and a LIBs (Laser-Induced Breakdown Spectroscopy) spectral detecting device. Kind.

Referring to Figure 2, the structure of the probe and the working principle of each structure are explained as follows:

The probe 11 includes: a light wave emitter 111, a dichroic color patch 112, a collimating device 113, a filtering component 113, and a focusing device 115;

The light wave emitter 11 is for emitting parallel light waves to the dichroic color patch 112. The light wave emitter 11 can be a laser, an infrared generator, a fluorescence generator, etc.; wherein, in order to generate parallel light waves emitted to the dichroic color patch 112, if the laser uses a point source such as a fiber laser, the laser light emitted by the laser passes through the quasi-light source. The straight lens is converted into a parallel light wave.

The dichroic color patch 112 is for reflecting parallel light waves emitted from the light wave emitter 11 to the collimating device 113. The collimating device 113 is for focusing and transmitting the parallel light waves reflected by the dichroic color patch 112 to the sample 13 to be detected. The collimating device 113 is further configured to receive the reflected light wave of the detected sample 13 and collimate the reflected light wave and transmit it to the dichroic color patch 112. Wherein, if Raman spectroscopy is performed, the reflected light wave of the detected sample 13 is the initial Raman signal collected by the probe, and the collimating device 113 allows the wavelength of the light to pass through is greater than the parallel light wave emitted by the light wave transmitter 111. The minimum wavelength of light, so that the generated light wave of the light wave transmitter 111 can be filtered out to avoid interference with the Raman signal. The dichroic patch 112 is also used to transmit light waves transmitted by the collimating device 113 to the filter assembly 114. The filtering component 114 is configured to filter the light wave transmitted by the dichroic color patch 112 and transmit it to the focusing device 115; the focusing device 115 is configured to focus the light wave transmitted by the filtering component and transmit it to the spectrometer. The filtering component 114 includes at least one filter. The minimum value of the band pass range of the filter is greater than the maximum wavelength of the parallel light wave emitted by the light wave emitter. Thus, the filter only allows the Raman signal to pass, and further filters out the generated light wave of the light wave transmitter 111. Thereafter, the probe 11 transmits the reflected light wave of the detected sample 13 to the spectrometer 12.

Referring to FIG. 3, an embodiment of the present invention provides a spectrometer comprising:

a spatial filter device 31, a beam splitting device 32, a collimating component 33 disposed on the optical wave input optical path of the spectroscopic device 32, and a focusing component 34 and a sensor 35 disposed on the optical wave output optical path of the spectroscopic device 32; wherein, the collimating component 33 Provided between the spatial filter device 31 and the beam splitting device 32, the focusing component 34 is disposed between the beam splitting device 32 and the sensor 35.

The functions of the various structures included in the spectrometer are described below:

The spatial filter unit 31 is configured to spatially filter the light wave outputted by the probe and emit at a predetermined scattering angle. The spatial filter member 31 can employ a slit.

The collimating component 33 is configured to collimate and output the light wave output from the spatial filter 31.

The beam splitting assembly 32 for diffracting the light wave output from the straight component 33 is diffracted according to the wavelength and output. The beam splitting device 32 includes a grating. For example: a planar grating, a holographic grating, wherein, as shown in FIG. 3, when a planar grating is used, the optical wave input optical path and the output optical path of the optical splitting device 32 are on the same side of the planar grating; as shown in FIG. 4, when a holographic grating is used, The light input optical path and the output optical path of the optical splitting device 32 are respectively located on both sides of the holographic grating.

The focusing component 34 is configured to focus and split the light wave outputted by the beam splitting component 32 and output the light.

The sensor 35 is configured to receive light waves output by the focusing component and generate corresponding spectra. The exemplary sensor 35 may be a CCD (Charge-coupled Device) or a CMOS.

Wherein, the collimating component 33 is further configured to adjust the focal length of the light wave on the incident light path of the light splitting device 32 in the first focal length range, and the distance between the incident surface and the exit surface of the collimating component 33 is smaller than the minimum system of the collimating component. The focal length; and/or the focusing component 34 is further configured to adjust the focal length of the light wave on the light exiting light path of the light splitting device in the second focal length range, and the distance between the incident surface and the exit surface of the focusing component 34 is smaller than the minimum system of the focusing component. focal length. Illustratively, the collimating assembly 33 can employ a collimating telephoto lens group or a collimating telephoto lens; the focusing assembly 34 can employ a focusing telephoto lens group or a focusing telephoto lens.

According to the spectrometer of the above structure, in an exemplary solution, the focal length of the spectrometer system can be increased from 25 mm to 35-50 mm in the prior art, and the resolution of the spectrometer is improved to the prior art. 1.5-2 times, the effective utilization area of CCD is 1.5-2 times.

In the above solution, the spectrometer includes a spatial filter device, a beam splitting device, a collimating component disposed on the optical wave input optical path of the spectroscopic device, and a focusing component and a sensor disposed on the optical wave output optical path of the spectroscopic device; wherein a collimating component is disposed between the spatial filter component and the spectroscopic device, the focusing component is disposed between the spectroscopic device and the sensor; the spatial filter component can spatially filter the optical wave output by the probe and emit at a predetermined scattering angle; the collimating component can The light wave outputted by the spatial filter is collimated and output; the light splitting component can illuminate the light wave outputted by the straight component according to the wavelength, and output; the focusing component can focus and output the light wave outputted by the collimating component; the sensor can receive Focusing on the light wave output by the component and generating a corresponding spectrum; in addition, the collimating component is further configured to adjust a focal length of the light wave on the incident light path of the light splitting device in the first focal length range, between the incident surface and the exit surface of the collimating component The distance is less than the minimum system focal length of the collimating component; and/or, the focusing component Also used to adjust the focal length of the light wave on the light exiting light path of the light splitting device in the second focal length range, the distance between the incident surface and the exit surface of the focusing component is smaller than the minimum system focal length of the focusing component; thus, due to the incident surface of the collimating component The distance from the exit surface is smaller than the minimum system focal length of the collimating assembly and/or the distance between the incident surface and the exit surface of the focusing assembly is smaller than the minimum system focal length of the focusing assembly, so that the miniaturization of the spectrometer is more advantageous, and Compared to the technology, a smaller volume can achieve the same or higher sensitivity than the prior art, while improving spectral resolution and spectral measurement range.

The specific embodiments of the present invention have been described in detail with reference to the preferred embodiments of the present invention. The scope of the protection, any modifications, equivalent substitutions, improvements, etc., which are made on the basis of the technical solutions of the present invention, are included in the scope of the present invention.

Claims

A spectrometer characterized by comprising:

a spatial filter device, a beam splitting device, a collimating component disposed on the optical wave input optical path of the spectroscopic device, and a focusing component and a sensor disposed on the optical wave output optical path of the spectroscopic device; wherein the collimating component is disposed on Between the spatial filter device and the light splitting device, the focusing component is disposed between the light splitting device and the sensor;

The spatial filter component is configured to spatially filter the optical wave output by the probe and emit at a predetermined scattering angle;

The collimating component is configured to collimate and output light waves output by the spatial filter;

The light splitting component is configured to diffract light waves outputted by the collimating component according to a wavelength, and output the same;

The focusing component is configured to focus and split the light wave output by the beam splitting component, and output the light wave;

The sensor is configured to receive a light wave output by the focusing component and generate a corresponding spectrum;

Wherein the collimating component is further configured to adjust a focal length of the light wave on the light incident light path of the light splitting device in a first focal length range, and a distance between the incident surface and the exit surface of the collimating component is less than the standard a minimum system focal length of the straight component; and/or the focusing component is further configured to adjust a focal length of the light wave on the light exiting light path of the light splitting device in a second focal length range, the incident surface and the exit surface of the focusing component The distance between them is less than the minimum system focal length of the focusing assembly.
The spectrometer of claim 1 wherein said spectroscopic device comprises a grating.
The spectrometer of claim 2 wherein said grating comprises a planar grating, a holographic grating.
The spectrometer of claim 1 wherein said collimating assembly comprises: a collimating telephoto lens group or a collimating telephoto lens.
The spectrometer of claim 1, wherein the focusing component comprises: a focusing telephoto lens group or a focusing telephoto lens.
The spectrometer of claim 1 wherein said spatial filter member comprises a slit.
A spectrum detecting device, comprising:

a probe and the spectrometer of any of claims 1-6;

The probe is configured to emit a light wave to the detected sample, and receive a reflected light wave of the detected sample, and emit the reflected light wave to the spectrometer.
The apparatus according to claim 7, wherein said probe comprises: a light wave emitter, a dichroic color patch, a collimating device, a filtering component, and a focusing device;

The light wave emitter is configured to emit parallel light waves to the dichroic color patch;

The dichroic color patch is configured to reflect parallel light waves emitted by the light wave emitter to the collimating device;

The collimating device is configured to focus and transmit parallel light waves reflected by the dichroic color patch to the detected sample;

The collimating device is further configured to receive the reflected light wave of the detected sample, and collimate the reflected light wave to be transmitted to the dichroic color patch;

The dichroic color patch is further configured to transmit light waves transmitted by the collimating device to the filter assembly;

The filtering component is configured to filter light waves transmitted by the dichroic color patch and transmit the light to the focusing device;

The focusing device is configured to focus light waves transmitted by the filtering component and transmit to the spectrometer.
The apparatus of claim 8 wherein said filtering component comprises at least one filter.
The apparatus according to claim 9, wherein a minimum value of a band pass range of said filter is greater than a maximum wavelength of a parallel light wave emitted by said light wave emitter.