CN212341010U - Visual Raman probe, detector and system - Google Patents

Abstract

The utility model discloses a visual raman probe, detection instrument and system relates to raman detection field. The probe includes: the raman spectrometer comprises a raman spectrometer, a detection surface, a first optical filter, a second optical filter, a fly-eye lens, a first convergent lens and a second optical filter, wherein the raman spectrometer is arranged between an incident slit and the detection surface, the detection surface is provided with a sample to be detected, and the raman spectrometer also comprises: an excitation light source, an illumination light source and an imaging device. The utility model discloses can effectively avoid damaging the problem of the sample that awaits measuring such as jewelry jade because of burning out that the too little area that leads to of the energy density of probing point leads to can observe the sample that awaits measuring in real time when carrying out raman detection, when the sample that awaits measuring appears unusually or the damage vestige, in time stop detecting, thereby can protect the sample that awaits measuring such as jewelry jade better, prevent that the sample that awaits measuring from damaging.

Description

Visual Raman probe, detector and system

Technical Field

The utility model relates to a raman detects the field, especially relates to a visual raman probe, detection instrument and system.

Background

In recent years, the raman spectroscopy technology has been successfully applied to the fields of jewelry jade research and jewelry jade identification because of its advantages of no need of sample preparation, convenience and rapidness.

However, the detection mode of the conventional raman spectrometer is generally single-point detection, and all excitation light sources converge to one point, and because the spectral resolution of the raman spectrometer is generally high, narrow slits with the micron order of 25um, 50um and the like are used for slits used by the spectrometer, laser spots converged by the raman probe are generally in the same order as the slits, so that the problems that the energy density of a detection point is large, the detection area is too small and the like are caused, and thus samples to be detected such as jewelry, jade and the like can be damaged.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that to prior art not enough, provide a visual raman probe, detection instrument and system.

The utility model provides an above-mentioned technical problem's technical scheme as follows:

a visualization raman probe, comprising: the raman spectrometer comprises a raman spectrometer, a detection surface, a first optical filter, a second optical filter, a fly-eye lens, a first convergent lens and a second optical filter, wherein the raman spectrometer is arranged between an incident slit and the detection surface, the detection surface is provided with a sample to be detected, and the raman spectrometer further comprises: excitation light source, illumination light source and image device, wherein:

the first optical filter and the Raman light path form a first preset angle and is used for emitting exciting light emitted by the exciting light source into the Raman light path; the fly-eye lens is used for adjusting the spot size and the energy density of exciting light emitted to the sample to be detected; the first convergent lens is used for emitting the adjusted exciting light to the sample to be detected; the first optical filter is also used for emitting signals with the frequency higher than that of the excitation light source into the incidence slit from the signals reflected by the sample to be detected;

the illumination light source is used for emitting illumination light to the detection surface, and the second optical filter and the Raman optical path form a second preset angle and are used for emitting the illumination light reflected by the detection surface into the imaging device;

the imaging device is used for imaging according to the received illumination light.

The utility model provides an another kind of technical scheme of above-mentioned technical problem as follows:

a visual Raman detector comprises the visual Raman probe according to the technical scheme.

The utility model provides an another kind of technical scheme of above-mentioned technical problem as follows:

a visual raman detection system comprising a visual raman probe according to the above-described technical solution.

The utility model has the advantages that: the utility model discloses an add fly eye lens in the raman light path, carry out homogenization treatment to the beam of shot to the sample that awaits measuring, can adjust the facula size and the energy density of exciting light, thereby can effectively avoid burning out the problem that damages the sample that awaits measuring such as jewelry jade that the too little area that leads to of surveying because of the energy density of gauge point is big, and illuminate the sample that awaits measuring through adding the illumination light, light reflection to imaging device through the light filter in with the raman light path, can observe the sample that awaits measuring in real time when carrying out raman survey, appear unusually or when damaging the vestige at the sample that awaits measuring, in time the stop detection, thereby can protect the sample that awaits measuring such as jewelry jade better, prevent that the sample that awaits.

Advantages of additional aspects of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

Fig. 1 is a schematic structural framework diagram provided by an embodiment of a visual raman probe of the present invention;

fig. 2 is a schematic structural diagram of a fly-eye lens provided in an embodiment of a visual raman probe of the present invention;

fig. 3 is a schematic structural diagram provided by another embodiment of the visual raman probe of the present invention;

fig. 4 is a schematic structural view of a conventional raman probe.

Detailed Description

The principles and features of the present invention are described below in conjunction with the following drawings, the illustrated embodiments are provided to explain the present invention and not to limit the scope of the invention.

In recent years, a raman spectroscopy technology, as a micro-area nondestructive analysis technology, has been successfully applied to the fields of jewelry and jade science research and jewelry and jade identification, and has the advantages of no need of preparing a sample and convenience and rapidness, so as to obtain the affirmation of a jewelry identification expert, but the detection mode of the traditional raman spectrometer is generally single-point detection, and an excitation light source is converged to one point by a raman probe which is output in space or a raman probe which is output by an optical fiber, because the spectral resolution of the raman spectrometer is generally higher and generally reaches below 1nm, narrow slits with the magnitude of micrometers of 25um, 50um and the like are used by the spectrometer, and as known from the conjugate relation of imaging optical objects, the field of view of the raman probe is very small, and laser spots converged by the raman probe are generally in the same magnitude as the slits, so that the energy density of a detection point is very high, and the detected area is too small, so when measuring the jewelry jade, especially the jewelry jade with dark color, because the energy density of the detection point is too high, the jewelry jade is possible to photolyze, thereby damaging the jewelry jade, and the relatively nondestructive detection can not be achieved, because the laser energy is very strong, the surface of the jewelry jade is difficult to directly observe, therefore, when the surface of the jewelry jade is slightly damaged, the damage is difficult to stop in time.

Moreover, the conventional Raman probe is single-point detection, each measurement can only be performed on a micrometer-scale point, but the identification of the jewelry jade is more hopeful to be performed on a surface detection rather than a small part, namely the Raman detection can cover the whole jewelry jade.

However, in the raman spectrum detection device for jewelry and jade detection on the market at present, a portable laser raman spectrometer or a laser confocal micro-raman spectrometer is mostly adopted, and the main work flow of the raman probe is as follows regardless of the portable raman spectrometer or the confocal micro-raman spectrometer: excitation light emitted by the laser irradiates a sample to be measured through reflection of the dichroic mirror and focusing of the collecting light path, scattered light generated by the sample to be measured is collected through the collecting light path, Rayleigh scattered light in the scattered light is filtered by the dichroic mirror and the notch filter, and Raman scattered light is obtained and then is converged to a slit of the Raman spectrometer through the converging light path. And finally, coupling the Raman scattering signal to a Raman spectrometer through a slit for spectral analysis.

As shown in fig. 4, a schematic diagram of an exemplary conventional raman probe structure is provided, a laser 1 provides an excitation light source of a raman spectrometer, the emitted excitation light is collimated by a collimating lens 2, the collimated parallel light beam passes through a dichroic mirror 3, the excitation light emitted by the dichroic mirror 3 and the high-reflection laser 1 passes through the dichroic mirror 3, the high-reflection parallel light is converged on a sample 5 to be measured by a converging lens 4, the sample 5 to be measured is excited to generate a raman scattering signal, the raman scattering signal is collimated by the converging lens 4, the raman scattering signal collimated by the converging lens 4 passes through the dichroic mirror 3 again, at this time, the dichroic mirror 3 will pass through the raman scattering signal, the raman scattering signal passing through the dichroic mirror 3 passes through a filter 7 to filter interference signals such as sunlight, fluorescence, rayleigh scattering and the like, and finally the raman scattering signal is converged to a raman spectrometer system 9 by the converging lens 8, and (4) performing spectral analysis.

Wherein, the laser 1, the collimating lens 2, the dichroic mirror 3 and the converging lens 4 together form a raman probe 6, as can be seen from fig. 4, after the laser light emitted by the laser 1 passes through the series of optical systems, will be converged on the sample 5 to be measured in the form of a converged light beam, and since the spectral resolution of the raman spectrometer 9 is generally high, around 1nm, to achieve high resolution, the slits used by the raman spectrometer 9 typically do not exceed 50um, according to the object-image conjugate relation, after passing through each optical system, the laser emitted by the laser 1 is converged to the convergent spot size on the sample to be measured and the slit size used by the Raman spectrometer are in the same level, namely micron level, the excitation light energy density experienced by the sample 5 to be tested is high and, particularly for dark substances including dark substances jade, there is a risk of "igniting" the sample.

In view of this, the utility model provides a visual, raman probe of low energy density can realize relatively harmless measuring, but also can realize the face and survey, combines the example to explain specifically below.

As shown in fig. 1, for the utility model discloses the structure frame schematic diagram that the embodiment of visual raman probe provided, this probe is applicable to the sample 300 that awaits measuring such as the darker jewelry jade of measurement colour, can prevent effectively that the sample 300 that awaits measuring from damaging, can realize relatively harmless measuring, but also can realize the face and survey, and this probe includes: the raman optical path between the entrance slit 100 and the detection surface 200 of the raman spectrometer, the detection surface 200 is provided with a sample 300 to be detected, the raman optical path is sequentially provided with a first optical filter 11, a second optical filter 12, a fly-eye lens 13 and a first convergent lens 14, and the raman optical path further comprises: an excitation light source 10, an illumination light source 20, and an imaging device 30, wherein:

the first optical filter 11 and the raman optical path form a first preset angle, and is used for injecting exciting light emitted by the exciting light source 10 into the raman optical path; the fly eye lens 13 is used for adjusting the spot size and the energy density of the exciting light emitted to the sample 300 to be measured; the first convergent lens 14 is used for emitting the adjusted excitation light to the sample 300 to be measured; the first optical filter 11 is further configured to inject a signal with a frequency higher than that of the excitation light source 10 in the signals reflected by the sample 300 to be measured into the entrance slit 100;

the illumination light source 20 is configured to emit illumination light to the detection surface 200, and the second filter 12 forms a second preset angle with the raman optical path, and is configured to emit the illumination light reflected by the detection surface 200 into the imaging device 30;

the imaging device 30 is used for imaging according to the received illumination light.

It should be understood that, the probe can realize area detection by adding the fly-eye lens 13, the area of the detection surface 200 can be flexibly designed according to the requirement, and can reach the centimeter magnitude, the width of the area of the detection surface 200 is related to the focal lengths of the first convergent lens 14 and the fly-eye lens 13, and those skilled in the art can set the area according to the actual requirement, and details are not described herein.

Alternatively, the first filter 11 may be a dichroic mirror, the second filter 12 may be a high-pass filter, the fly-eye lens 13 may be a transmissive double-row fly-eye lens 13 or a transmissive single-row fly-eye lens 13, the excitation light source 10 may be a laser, the illumination light source 20 may be an incandescent lamp, a fluorescent lamp, an LED lamp, or the like, and the imaging device 30 may be a terminal device capable of receiving light and displaying, such as a video camera, a still camera, a computer, or the like.

It should be noted that fly-eye lens 13 is also called fly-eye lens or lens array, and is a lens array formed by combining a plurality of small lenses with the same parameters. The fly-eye lens 13 array is applied to an illumination system to obtain high light energy utilization rate and large-area uniform illumination, and the principle of realizing uniform illumination by the fly-eye lens 13 array is as follows: light beams parallel to the optical axis pass through the first block of lenses and are focused at the center of the second block of lenses, the first row of fly-eye lenses 13 illuminate the light source to form a plurality of light source images, and each small lens of the second row of fly-eye lenses 13 superposes and images the light source images formed by the first row of fly-eye lenses 13 on an illumination surface. Because the first row of fly eye lenses 13 divides the whole wide light beam of the light source into a plurality of beamlets for illumination, and the vertical axis nonuniformity within each beamlet range is mutually superposed due to the beamlets at the symmetrical positions, the vertical axis nonuniformity of the beamlets is compensated, and the light energy within the whole aperture is effectively and uniformly utilized.

As shown in fig. 2, taking the transmissive double-row fly-eye lens 13 as an example for explanation, the transmissive double-row fly-eye lens 13 utilizes the principle that the uniformity of many beamlets is greater than that of the whole wide beam, because the system is symmetrical along the optical axis, the tiny unevenness in each beamlet is compensated by the superposition of beamlets, so as to obtain an illumination surface with uniform illumination, as shown in fig. 2, the front row fly-eye lens array 131 and the back row fly-eye lens array 132 can be arranged in parallel with each other, the collimated wide beam is split into beamlets by the front row fly-eye lens array 131, and converges at the central position of each lenslet of the back row fly-eye lens array 132, the optical and structural parameters of the front row fly-eye lens array 131 and the back row fly-eye lens array 132 are completely consistent, including the material, the curvature, the size of the lenslet, and the like, the back row fly-eye lens array 132 serves as a field lens, because the front row fly-eye lens array 131 divides the whole wide beam into a plurality of beamlets, and the tiny nonuniformity in the range of each beamlet is mutually overlapped due to the beamlets at the symmetrical positions, the tiny nonuniformity of the beamlets is compensated, and the light energy in the whole aperture is effectively and uniformly utilized. Light spots emitted from the back fly-eye lens array 132 are projected onto the illumination surface 134 through the condenser lens 133, each point of the light spots on the illumination surface 134 is irradiated by light beams emitted by all points of the light source, and meanwhile, the light beams emitted by each point of the light source are intersected and overlapped in the same field range on the illumination light spots, so that uniform illumination light spots are obtained.

The uniformity of the light spots on the illumination surface 134 is related to the number of the unit arrays of the fly-eye lens 13 array, and the more the number of the unit arrays, the more uniform the illumination, and meanwhile, under the condition that the optical focal length of the condenser lens 133 is fixed, the number of the unit arrays is negatively related to the area of the illumination surface 134, that is, the more the number of the unit arrays, the smaller the area of the illumination surface 134 is, so in practical application, the number of the unit arrays can be determined according to the specific design requirements.

First, excitation light emitted by the excitation light source 10 passes through the first optical filter 11 and the second optical filter 12 in sequence and then irradiates the fly eye lens 13, and the fly eye lens 13 degausses the gaussian laser emitted by the excitation light source 10, that is, a surface light spot is formed by a gaussian light spot, and the surface light spot is located on the front focal plane of the first converging lens 14 and is imaged on the detection surface 200.

In order to realize the visualization of the raman probe, a video monitor is introduced into the whole raman optical path, the whole video monitor may adopt paraxial illumination, the illumination light source 20 illuminates the detection surface 200 in a paraxial illumination mode, the scattered light is collimated into parallel light after passing through the first converging lens 14 and the fly eye lens 13 in sequence, the illumination parallel light is reflected to the imaging device 30 after passing through the second optical filter 12, and an image of the detection surface 200 is formed by the imaging device 30.

Optionally, because the second optical filter 12 reflects parallel light, a converging lens may be further added between the second optical filter 12 and the imaging device 30, the converging lens and the first converging lens 14 together form a set of magnifying optical system, the optical magnification is equal to the ratio of the focal length of the converging lens to the focal length of the first converging lens 14, generally, the first converging lens 14 is not adjusted, and the magnification may be flexibly adjusted according to the focal length of the converging lens, so as to achieve the function of microscopic magnification and obtain a clearer image of the detection surface 200.

The sample 300 to be detected on the detection surface 200 is excited by the excitation light source 10 to generate a raman scattering signal and noise interference signals including rayleigh scattering and the like, according to the principle that the light path is reversible, the signals sequentially pass through the first converging lens 14 and the fly eye lens 13 and then become parallel light, when passing through the second optical filter 12, the illumination light path is highly reflected to the video monitoring light path and enters the imaging device 30, so that the signal and the illumination light beam of the sample 300 to be detected, which are excited by the excitation light source 10, are split by the high-pass optical filter, the raman scattering signal and the rayleigh scattering and the like are transmitted to the first optical filter 11 along the main light path, the first optical filter 11 passes the signal with the frequency higher than that of the excitation light source 10 to the entrance slit 100, and the signal is spatially filtered by.

Optionally, since the signal that has passed through the entrance slit 100 includes interference noise signals such as rayleigh scattering in addition to the raman scattering signal, an optical filter for filtering the rayleigh scattering signal may be added between the first optical filter 11 and the entrance slit 100, so as to improve the raman detection effect.

Alternatively, since the entrance slit 100 is narrow, a converging lens may be disposed in front of the entrance slit 100 to converge the raman scattering signal.

It should be noted that, when the imaging device 30 finds that the surface of the sample to be detected is abnormal, the excitation light source 10 may be directly turned off to stop the raman detection, so as to prevent the sample to be detected from being further damaged, and the power of the excitation light source 10 may also be reduced to continue the detection, so as to prevent the sample to be detected from being further damaged.

It should be understood that whether the surface of the sample is abnormal or not can be determined by means of manual observation, for example, whether the color or shape of the part of the surface of the sample to be detected for raman changes or not can be determined.

The identification can also be judged automatically by a machine. For example, it can be implemented by programming to capture a reference image of the sample to be detected before performing the raman detection, then obtain an image of the sample to be detected in real time during the raman detection, and then compare the image with the reference image, thereby determining whether the sample to be detected has a change in shape or color.

Alternatively, the first frame image received by the imaging device 30 after raman detection may be selected as the reference image.

This embodiment is through adding fly eye lens 13 in the raman light path, carry out homogenization treatment to the beam of shooting to the sample 300 that awaits measuring, can adjust the facula size and the energy density of exciting light, thereby can effectively avoid burning the problem that damages the sample 300 that awaits measuring such as jewelry jade that the too little area that leads to of surveying because of the energy density of gauge point is very big, and illuminate the sample 300 that awaits measuring through adding the illumination light, reflect the illumination light in with the raman light path to imaging device 30 through the light filter, can observe the sample 300 that awaits measuring in real time when carrying out raman survey, when the sample 300 that awaits measuring appears unusually or the damage trace, in time the stop to detect, thereby can protect sample 300 that awaits measuring such as jewelry jade better, prevent that the sample 300 that await.

Other implementations of an exemplary visualization raman probe are provided as shown in fig. 3, and other optional improvements of the present invention are described below in conjunction with fig. 3.

Optionally, in some possible implementations, a second converging lens 15 is further disposed in the raman optical path, and the second converging lens 15 is disposed between the entrance slit 100 and the first filter 11.

Optionally, in some possible implementations, a third filter 16 is further disposed in the raman optical path, and the third filter 16 is disposed between the second converging lens 15 and the first filter 11, and is configured to filter a rayleigh scattering signal in a signal reflected by the sample 300 to be measured.

By providing the third optical filter 16, the accuracy of raman detection can be improved.

Optionally, in some possible implementations, the method further includes: and the fourth filter 17, wherein the fourth filter 17 is arranged between the excitation light source 10 and the first filter 11, and is used for filtering noise of the excitation light.

By filtering out noise in the excitation light, the accuracy of raman detection can be improved.

Alternatively, the fourth filter 17 may be a narrow bandwidth filter.

Optionally, in some possible implementations, the method further includes: and the collimating mirror 18, the collimating mirror 18 being arranged between the fourth optical filter 17 and the first optical filter 11, and being used for collimating the exciting light.

Optionally, in some possible implementations, the method further includes: a third condensing lens 19, the third condensing lens 19 being disposed between the imaging device 30 and the second filter 12.

Optionally, in some possible implementations, fly-eye lens 13 is a single-row fly-eye lens or a double-row fly-eye lens.

It is to be understood that some or all of the various embodiments described above may be included in some embodiments.

In other embodiments of the present invention, there is provided a visual raman detector, comprising a visual raman probe according to any of the above embodiments.

In other embodiments of the present invention, there is also provided a visual raman detection system comprising a visual raman probe as described in any of the above embodiments.

The reader should understand that in the description of this specification, reference to the description of the terms "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily think of various equivalent modifications or replacements within the technical scope of the present invention, and these modifications or replacements should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims (9)

1. A visualization raman probe, comprising: the Raman spectrometer is characterized in that a first optical filter, a second optical filter, a fly-eye lens and a first convergent lens are sequentially arranged in the Raman optical path, and the Raman optical path further comprises: excitation light source, illumination light source and image device, wherein:

the first optical filter and the Raman light path form a first preset angle and is used for emitting exciting light emitted by the exciting light source into the Raman light path; the fly-eye lens is used for adjusting the spot size and the energy density of exciting light emitted to the sample to be detected; the first convergent lens is used for emitting the adjusted exciting light to the sample to be detected; the first optical filter is also used for emitting signals with the frequency higher than that of the excitation light source into the incidence slit from the signals reflected by the sample to be detected;

the illumination light source is used for emitting illumination light to the detection surface, and the second optical filter and the Raman optical path form a second preset angle and are used for emitting the illumination light reflected by the detection surface into the imaging device;

the imaging device is used for imaging according to the received illumination light.

2. The visualization raman probe of claim 1, further comprising a second converging lens disposed in the raman optical path between the entrance slit and the first filter.

3. The visualization raman probe according to claim 2, wherein a third optical filter is further disposed in the raman optical path, and the third optical filter is disposed between the second converging lens and the first optical filter, and is configured to filter a rayleigh scattering signal in a signal reflected by the sample to be measured.

4. A visualization raman probe according to any one of claims 1 to 3, further comprising: and the fourth optical filter is arranged between the excitation light source and the first optical filter and is used for filtering noise of the excitation light.

5. The visualization raman probe of claim 4, further comprising: and the collimating mirror is arranged between the fourth optical filter and the first optical filter and is used for collimating the exciting light.

6. A visualization raman probe according to any one of claims 1 to 3, further comprising: a third condenser lens disposed between the imaging device and the second filter.

7. The visualization raman probe of claim 1, wherein the fly-eye lens is a single row fly-eye lens or a double row fly-eye lens.

8. A visual raman detector comprising the visual raman probe of any one of claims 1 to 7.

9. A visualization raman detection system comprising the visualization raman probe of any one of claims 1 to 7.

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