CN106595861A - Spatial resolution spectrum acquisition system - Google Patents

Abstract

The invention provides a spatial resolution spectrum acquisition system. Since an acquisition optical fiber is a single-core optical fiber, for an incident light field of any shape, an emergent light field is in total light intensity distribution in approximately circular symmetry, thus spectral signals exported to N spectrographs through beam splitting by optical fiber bundles are spectral signals in the same spatial position to be tested, the problem that measured spatial positions are inconsistent when N fiber optic spectrometers are used concurrently is solved, and high-reliability spatial resolution measurement is guaranteed to be realized when the N spectrometers are used to perform measurement concurrently.

Description

A Spatial Resolution Spectrum Acquisition System

technical field

The invention relates to the technical field of space resolution measurement, in particular to a space resolution spectrum acquisition system.

Background technique

The fiber optic spectrometer transmits the spectral signal to the spectrometer through an optical fiber. If there is no other optical device between the fiber collection end face and the space to be measured, it collects the spectrum of the entire space to be measured. However, in practical applications, it is often necessary to only collect spectral signals within a small spatial range in the space to be measured, that is, spatially resolved measurement. At this time, it is necessary to place a signal light collection optical path between the spatial position to be measured and the collection end face of the optical fiber, and image the spatial position to be measured to the collection end face of the optical fiber to achieve spatial resolution measurement.

In practical applications, due to the limited band range of a single spectrometer, sometimes multiple spectrometers are used for joint measurement; in the prior art, the solution for realizing joint measurement of multiple spectrometers is generally to use more than one optical fiber bundle, see Figure 1 , the fiber bundle includes combined fibers and split fibers; firstly, a combined fiber (see Figure 2) containing several fiber cores is used to collect signal light, and then the signal light is guided into different split fibers through each fiber core (see Figure 2). Figure 3), and then passed to different spectrometers respectively.

However, in this solution in the prior art, since the conjugate planes of each fiber core end face in the composite fiber correspond to different spatial positions to be measured through the signal light collection optical path, as shown in Fig. The measured spatial positions are not consistent, and the real spatial resolution measurement cannot be realized.

Contents of the invention

The invention provides a space resolution spectrum acquisition system to solve the problem in the prior art that the measured spatial positions are inconsistent when a plurality of spectrometers measure together.

In order to achieve said purpose, the technical scheme provided by the application is as follows:

A spatially resolved spectrum acquisition system, which is applied to spatially resolved measurements when N spectrometers are used together, where N is a positive integer greater than 1; the spatially resolved spectrum acquisition system includes:

The signal light collection optical path is used to collect the spectral signal at the spatial position to be measured;

A collection optical fiber is used to transmit the spectral signal; the collection optical fiber is a single-core optical fiber, and for an incident light field of any shape, the outgoing light field has a total light intensity distribution close to circular symmetry;

An optical fiber bundle, for splitting and exporting the spectral signal emitted by the collection optical fiber to N spectrometers;

The optical fiber connector is used to connect the output end of the collection optical fiber and the input end of the optical fiber bundle, so that the spectral signal emitted by the collection optical fiber is transmitted into the optical fiber bundle.

Preferably, through the connection of the optical fiber connector, the core end face of the output end of the collection optical fiber overlaps with each core end face of the input end of the optical fiber bundle.

Preferably, through the connection of the optical fiber connector, the core end face of the output end of the collection optical fiber is larger than and can cover each core end face of the input end of the optical fiber bundle.

Preferably, the signal light collection optical path is a conjugate optical device, the spatial position to be measured is used as the object plane of the conjugate optical device, and the core end face of the incident end of the collection optical fiber is the image of the conjugate optical device noodle.

Preferably, the conjugate optical device is: a single lens, a lens group, a specific surface mirror or a mirror group.

Preferably, the length of the collection fiber is greater than a preset length; the preset length is a length corresponding to the core diameter and numerical aperture of the collection fiber.

The spatially resolved spectrum acquisition system provided by the present invention, since the acquisition optical fiber is a single-core optical fiber, and for any shape of the incident light field, the outgoing light field has a total light intensity distribution close to circular symmetry, so after passing through the optical fiber bundle, the beam is split The spectral signals exported to N spectrometers are all spectral signals at the same spatial position to be measured, which can solve the problem of inconsistency in the measured spatial positions when N optical fiber spectrometers are used together, and ensure that high Spatially resolved measurements of reliability.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic structural view of a beam splitter provided by the prior art;

Fig. 2 is the end face schematic diagram of the synthetic fiber that prior art provides;

Fig. 3 is the end face schematic diagram of the split fiber that prior art provides;

Fig. 4 is a schematic structural diagram of a spatially resolved spectrum acquisition system provided by the prior art;

5 is a schematic structural diagram of a spatially resolved spectrum acquisition system provided by an embodiment of the present invention;

Fig. 6 is another schematic structural diagram of a spatially resolved spectrum acquisition system provided by another embodiment of the present invention.

detailed description

In order to make the above objects, features and advantages of the present invention more comprehensible, specific implementations of the present invention will be described in detail below in conjunction with the accompanying drawings.

The invention provides a space resolution spectrum acquisition system to solve the problem in the prior art that the measured spatial positions are inconsistent when a plurality of spectrometers measure together.

Specifically, the spatially resolved spectrum acquisition system is applied to the spatially resolved measurement when N spectrometers are used together, see FIG. Connector 104; N is a positive integer greater than 1; wherein:

The signal light collection optical path 101 is used to collect the spectral signal at the spatial position to be measured;

The collection optical fiber 102 is used to transmit spectral signals; and the collection optical fiber 102 is a single-core optical fiber, and for an incident light field of any shape, its outgoing light field is a total light intensity distribution close to circular symmetry;

The optical fiber bundle 103 is used to split and export the spectral signal emitted by the collecting optical fiber to N spectrometers;

The optical fiber connector 104 is used to connect the output end of the collection optical fiber 102 and the input end of the optical fiber bundle 103 , so that the spectral signal emitted by the collection optical fiber 102 is transmitted to the optical fiber bundle 103 .

Referring to Fig. 5, the spectral signal at the spatial position to be measured is transmitted to a single-core collection optical fiber 102 through the signal light collection optical path 101, and then transmitted to a multi-fiber bundle 103 through the collection fiber 102, and then split and exported to multiple spectrometers.

In the spatially resolved spectrum acquisition system provided in this embodiment, since the acquisition optical fiber 102 is a single-core optical fiber, and for an incident light field of any shape, the outgoing light field has a total light intensity distribution that is close to circular symmetry, so through the optical fiber bundle 103 The spectral signals exported to N spectrometers after beam splitting are all spectral signals at the same spatial position to be measured, which can solve the problem of inconsistency in the measured spatial positions when N optical fiber spectrometers are used together, and ensure that when N spectrometers are used to measure together Highly reliable spatially resolved measurements can be achieved.

Another embodiment of the present invention provides a specific spatially resolved spectrum acquisition system, on the basis of FIG. 5 and the above-mentioned embodiments:

The signal light collection optical path 101 is a conjugate optical device with a preset focal length, the spatial position to be measured is used as the object plane of the conjugate optical device, and the core end face of the incident end of the collection fiber is the image plane of the conjugate optical device.

Preferably, the conjugate optical device can be: a single lens, a lens group, a specific surface mirror or a mirror group and other optical devices; for example, referring to FIG. 6, the conjugate optical device is a single convex lens with a focal length of 30 mm.

Moreover, for an incident light field of any shape, the output light field of the collection fiber 102 is the superposition of axisymmetric optical fiber eigenmodes, so that the total light intensity distribution is close to circular symmetry;

In a specific practical application, the length of the collection optical fiber 102 can be optimized according to its own core diameter and numerical aperture. value.

Therefore, the length of the collection fiber 102 should be greater than the preset length; the preset length is the length corresponding to the core diameter and numerical aperture of the collection fiber 102; for example, the core diameter of the collection fiber 102 can be 600um, and the length of the collection fiber 102 Can be 0.5m.

Since the focal length of a single convex lens and the core diameter of the collection optical fiber 102 jointly determine the spatial resolution of the spatially resolved spectrum collection system, in specific practical applications, the focal length and collection of a single convex lens can be adjusted according to its application environment. The core diameter and length of the optical fiber 102 are preset, and this is only an example, not necessarily limited thereto, and all are within the protection scope of the present application.

Another embodiment of the present invention provides a specific spatially resolved spectrum acquisition system. On the basis of FIG. 5 and the above-mentioned embodiments, see FIG. 6:

The optical fiber bundle 103 includes a composite fiber 301 and N branch fibers 302; N is a positive integer greater than 1;

The synthetic fiber 301 includes N fiber cores;

The split fiber 302 includes a fiber core, and the fiber cores in the N split fibers 302 communicate with the N fiber cores in the combined fiber 301 in a one-to-one correspondence;

Specifically, through the connection of the optical fiber connector 104, the fiber core end face of the exit end of the collection fiber 102 overlaps with each core end face of the incident end of the fiber bundle 103; more preferably, the core end face of the exit end of the collection fiber 102 is larger than and Each core end face of the incident end of the fiber bundle 103 can be covered.

Preferably, the core diameters of the fiber core in the composite fiber 301 and the fiber core of the split fiber 302 are both 200 um.

Moreover, the optical fiber connector 104 can be a standard optical fiber coupler such as SMA905, FC or SC.

In a specific practical application, the optical fiber connector 104 can be any standard optical fiber connector, which can realize the connection between the collection optical fiber 102 and the optical fiber bundle 103. There is no specific limitation here, and it can be determined according to the specific application environment. All within the scope of protection of this application.

In addition, the core diameter of the collection optical fiber 102, the core diameter of the fiber core in the composite fiber 301 and the fiber core of the split fiber 302 can also be selected separately, as long as the core end face of the exit end of the collection fiber 102 (i.e. the core of the collection fiber 102 diameter) and each core end face of the incident end of the optical fiber bundle 103 (that is, the total end faces of the N cores in the composite fiber 301) can overlap, and there is no specific limitation here, depending on the specific application environment All are within the protection scope of the present application.

Figure 6 shows that N is 3 as an example. In a specific practical application, it is also possible to select a suitable optical fiber bundle 103 according to the actual number of spectrometers in its actual application environment, which is not necessarily limited to the one shown in Figure 6. The fiber bundle divided into three is only an example here, and various solutions that can realize common measurement by multiple spectrometers are within the protection scope of the present application.

Preferably, on the basis of FIG. 5 , FIG. 6 and the above-mentioned embodiments, the spatially resolved spectrum collection system may further include: mechanical parts for fixing the signal light collection optical path 101 and the incident end of the collection optical fiber 102 .

Preferably, the mechanical part fixes the distance between the signal light collection optical path 101 and the incident end face of the collection optical fiber 102 to be 35 mm.

The installation process of the spatially resolved spectral acquisition system is as follows:

Firstly, connect the single-core collection fiber 102 with a thicker core diameter and the composite fiber 301 of the multi-fiber bundle 103 with a standard fiber coupler such as SMA905, FC or SC to form the optical path of the fiber part.

Then adjust the fixed relationship between the mechanical part and the incident end surface of the collection fiber 102 and the signal light collection optical path 101 , so that a preset spatial position to be measured is imaged on the incident end surface of the collection fiber 102 .

Finally, the N split fibers 302 of the fiber bundle 103 are connected to N spectrometers respectively; taking N as 3 as an example for illustration, the three split fibers 302 of the fiber bundle 103 are connected to three spectrometers respectively, that is, a high-reliability space The resolution measurement, which is not specifically limited here, is within the protection scope of the present application.

It is worth noting that in the prior art, since the connection between the optical fiber bundle and the signal light collection optical path cannot always be fixed, the repeatability of the spectrometer detection signal cannot be guaranteed after plugging and unplugging.

However, the spatially resolved spectral acquisition system provided in this embodiment can be put into use through the above-mentioned installation process; when the spatially resolved spectral acquisition system is applied to N spectrometers for joint measurement, a real spatial Resolution measurement, and can also ensure the repeatability of the spectrometer detection signal after plugging and unplugging; this is necessary in spectral analysis applications that require spatial resolution measurement.

The specific working principles are the same as those of the above-mentioned embodiments, and will not be repeated here.

Each embodiment of the present invention is described in a progressive manner, each embodiment focuses on the differences from other embodiments, and the same and similar parts of the various embodiments can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for the related information, please refer to the description of the method part.

The above descriptions are only preferred embodiments of the present invention, and do not limit the present invention in any form. Although the present invention has been disclosed above with preferred embodiments, it is not intended to limit the present invention. Any person familiar with the art, without departing from the scope of the technical solution of the present invention, can use the methods and technical content disclosed above to make many possible changes and modifications to the technical solution of the present invention, or modify it into an equivalent of equivalent change Example. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention, which do not deviate from the technical solution of the present invention, still fall within the protection scope of the technical solution of the present invention.

Claims (6)

1. A spatially resolved spectral acquisition system, characterized in that, it is applied to the spatially resolved measurement when N spectrometers are used together, and N is a positive integer greater than 1; the spatially resolved spectral acquisition system comprises: The signal light collection optical path is used to collect the spectral signal at the spatial position to be measured; A collection optical fiber is used to transmit the spectral signal; the collection optical fiber is a single-core optical fiber, and for an incident light field of any shape, the outgoing light field has a total light intensity distribution close to circular symmetry; An optical fiber bundle, for splitting and exporting the spectral signal emitted by the collection optical fiber to N spectrometers; The optical fiber connector is used to connect the output end of the collection optical fiber and the input end of the optical fiber bundle, so that the spectral signal emitted by the collection optical fiber is transmitted into the optical fiber bundle. 2. The spatially resolved spectrum acquisition system according to claim 1, characterized in that, through the connection of the optical fiber connector, the core end face of the output end of the collection optical fiber and each core end face of the incident end of the optical fiber bundle are uniform. There is overlap. 3. The spatially resolved spectrum acquisition system according to claim 2, characterized in that, through the connection of the optical fiber connector, the core end face of the exit end of the collection optical fiber is larger than and can cover each fiber at the entrance end of the optical fiber bundle. Core end face. 4. The spatially resolved spectrum acquisition system according to claim 1, wherein the signal light acquisition optical path is a conjugate optical device, and the spatial position to be measured is used as the object plane of the conjugate optical device, and the The fiber core end face at the incident end of the collection fiber is the image plane of the conjugate optical device. 5 . The spatially resolved spectrum acquisition system according to claim 4 , wherein the conjugate optical device is: a single lens, a lens group, a specific surface mirror or a mirror group. 6 . 6. The spatially resolved spectrum acquisition system according to claim 1, wherein the length of the acquisition optical fiber is greater than a preset length; the preset length is the length corresponding to the core diameter and numerical aperture of the acquisition optical fiber .