CN115137360A - Signal light collector - Google Patents

Abstract

The invention provides a signal light collector, wherein the contour lines on two sides of a longitudinal section are curves on a parabola which is symmetrical about the central axis of the longitudinal section, and the signal light collector comprises a reflecting area arranged on the inner surface of a side wall, an opening area on the top surface and a light transmitting area on the bottom surface; the area of the opening area is larger than that of the light-transmitting area; and the signal light transmitted by the light transmitting area is collimated by the reflecting area and then emitted out of the opening area in a parallel light beam manner. An annular waveguide layer is also included. The signal collection efficiency is improved, and the safety is high; the device has the advantages of simple structure, low cost, high efficiency, flexibility and convenience in setting.

Description

Signal light collector

Technical Field

The invention belongs to the technical field of optical detection, and particularly relates to a signal light collector.

Background

This section is intended to provide a background or context to the embodiments of the invention that are recited in the claims. The description herein is not admitted to be prior art by inclusion in this section.

The application of the optical detection technology has been popularized in various fields in life, and particularly, the optical detection technology has universal application in medical examination related to human health and further needs to be further deepened and popularized. The biological characteristics can be reflected through the characteristics of the signal light, and treatment and daily health monitoring can be powerfully supported after analysis.

For example, the Raman spectrum detection technology is widely applied to the fields of food safety, biomedical archaeological public and the like, and has great value on qualitative analysis and substructure solution of substances. Especially in the application of the biomedical field, the Raman spectrum detection technology can reflect the change of human tissue cell molecules, and is a new technology for early-stage lesion detection. The method has the characteristics of no pain, no wound, simplicity, rapidness and the like, can solve the problems of the conventional detection method, and is one of potential methods for applying the non-invasive biochemical analysis of blood. Different Raman peaks are the characteristics of certain specific molecules, so that the Raman spectrum has the functions of qualitative analysis and distinguishing similar substances, the peak intensity of the Raman spectrum is in direct proportion to the concentration of the corresponding molecules, and the Raman spectrum can also be used for quantitative analysis and can provide a theoretical basis for clinical diagnosis. Whether the blood sample is affected by the disease can be judged according to the characteristic peak intensity of the blood sample in the Raman spectrum in the future.

Taking raman detection system as an example, the existing optical detection system generally includes a laser light source, a light path component, and a detection component. The Raman signal light is collected, filtered and transmitted to a detection component, and the Raman signal intensity at different wavelengths is detected. The exciting light is focused into a point to irradiate the surface of the sample, the generated Raman signal light radiates to the periphery by taking the exciting light irradiation point as the center, and the Raman light collection system of the light path component is limited by the numerical aperture NA and the working distance of the lens and can only collect Raman radiation signals within a very small range angle, so that the relatively weak Raman signals are weaker and difficult to detect.

Therefore, how to effectively and sufficiently collect signals in optical detection is a prominent problem of optical path design in an optical detection system and is one of the key designs to be optimized in the prior art. On the other hand, the problem before collection is how to accurately focus the excitation light to the location to be detected, which concerns the complexity of sample preparation and whether it can be deployed outside the laboratory.

Of which the application in subcutaneous biomarker detection is particularly prominent. The skin, the organ with the largest surface area and the most useful, accounts for approximately eight percent of the total weight of the human body, contains 25 to 30 percent of the total circulating blood of the human body, and consists of epidermis, dermis and subcutaneous fat. Tissue fluid or blood under the skin contains many biospecific markers that are closely related to the health and disease status of the human body. However, many of the current medical techniques are difficult to pass through the skin to the organismThe marker is used for non-invasive detection, for example, blood sugar detection requires blood drawing test, or blood drawing by finger. The use of optical detection techniques is essential if they can be used for non-invasive subcutaneous medical testing, especially if the general population can monitor the health of an individual at a location outside of a medical laboratory. For example, in the application of the conventional raman spectroscopy, which can only test the depth of hundreds of micrometers below the surface, and detect the spectral information of the deep subcutaneous biomarkers without damage, as shown in fig. 1, the excitation light is focused and irradiated on the living body through the first optical path L1, signal light is generated at different tissue depths (skin a, subcutaneous tissue B, blood vessels U) in the excitation region and around the excitation region and returns from the second optical path L2, and according to the photon migration theory, the offset distance Δ s from the central excitation point along the spatial offset direction X is determined according to the photon migration theory ₁ The larger the signal light corresponding to the biometric signal from the deeper sample. It is apparent that a new signal light collector is required to detect the signal light of a deeper layer. Therefore, there is a need to design a signal light collector suitable for non-invasive biometric signal detection.

The above information disclosed in this background section is only for enhancement of understanding of the background of the disclosure and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. The statements in this background section merely indicate prior art as known to the public and are not, of course, representative of existing art in this field.

Disclosure of Invention

The present invention has been made to solve all or part of the above-mentioned problems occurring in the prior art, and the present invention provides a signal light collector.

The following description is made of some principles and concepts which may be related to the invention and are intended to be illustrative or schematic in nature and not restrictive in character, and is not intended to limit the scope of the invention.

The invention is based on the principle of the SORS technology, and the basic starting point is the photon migration theory, as shown in figure 1, when laser is incident to the surface layer of a sample to be measured, the surface layer sample is excited or scattered to generate broadband fluorescence, wherein one part of the broadband fluorescence isScattered light reaches the inside of the sample, raman scattering photons generated at the deep layer inside the sample are easier to transversely migrate in the scattering process compared with photons on the surface layer of the sample, and the Raman scattering photons return to the surface layer of the sample after being scattered for multiple times and are collected. Different space offset distances deltas are arranged between the positions of the scattered lights reaching different depths in the sample and returning to the surface layer and the incident points of the laser light sources in the X direction on the surface layer of the sample ₁ 。

Based on the principle, the invention provides a signal light collector aiming at the particularity of the detection of the characteristic signal of the internal marker of the biological tissue, in particular to the acquisition of the deep biological characteristic signal of the subcutaneous tissue, and aiming at solving all or part of the problems in the prior art.

The invention provides a signal light collector, which is provided with an upper opening and a lower opening, wherein the contour lines on two sides of a longitudinal section of the collector are parabolic segments symmetrical about a central axis, and the collector comprises a reflection area on the inner surface, an opening area on the top surface and a light transmission area on the bottom surface; the area of the opening area is larger than that of the light-transmitting area; and the signal light transmitted by the light transmitting area is collimated by the reflecting area and then emitted out of the opening area in a parallel light beam manner.

The reflecting area surface is high reflectivity material, can carry out the deflection with the light of signal light collector bottom surface certain angle within range incident printing opacity district, all turn into the parallel light beam output that is on a parallel with signal light collector center pin, can be collected the bottom surface and come from the signal collection light path of outputting to the top after biological tissue's the divergent signal light of gathering carries out the collimation, the follow-up receipt of being convenient for. The signal light collector collects and collimates the signal light which is generated at the specific tissue depth and is diverged to different directions sufficiently through the reflection area and then converges to the detector, so that the collection efficiency is improved, and meanwhile, the structure is simple and the reduction of equipment cost is facilitated.

The light-transmitting area is centered on the central axis.

The intersection point of the plane of the light-transmitting area and the central axis is between the vertex and the focus of the parabola.

In an embodiment, the preset distance from the edge to the center of the light-transmitting area ranges from 0.1mm to 10mm, wherein the preferable range is from 2mm to 5mm.

The minimum width of the opening area is larger than the drift diameter length of the parabolic segment.

The entire inner surface of the collector is the reflective region. And the intensity of the collected signal light is controlled by changing the included angle between the incident limiting line of the height-adjusting signal light reaching the reflecting area, which is parallel to the direction of the central shaft, and the central shaft.

The reflective surface material of the reflective region includes, but is not limited to, specular silver or polished specular aluminum oxide.

The collector is a light collecting ring with an upper opening and a lower opening, namely the side wall of the collector is a light collecting ring formed by rotating a parabolic segment around the central shaft.

The outer surface of the side wall is provided with an annular waveguide layer along the direction of the parabolic segment, the light collecting ring is an annular waveguide, and light is transmitted to the emergent surface of the annular waveguide from the top to the bottom of the incident surface of the annular waveguide; the exit surface and the bottom surface of the annular waveguide are in the same plane. When the annular light beam is coupled into the incident surface of the annular waveguide layer, the annular light beam is emitted from the emergent surface of the annular waveguide layer to form an annular light spot; the inner circle of the annular emergent surface is overlapped with the edge of the bottom surface. The distance from the central area of the annular light spot to the annular excitation area can be determined by the size design of the signal light collector, namely the size of the bottom surface can be preset according to the spatial offset distance, and the annular excitation light can be used for annularly exciting the biological characteristic signal from the specified depth of the organism.

The annular waveguide layer is an annular optical fiber array or an annular transparent light guide structure.

The intersection point of the plane of the incident surface of the annular waveguide layer and the central axis is on the opening area or on one side of the opening area from the light transmission area.

The thickness range of the annular waveguide is 0.1mm-10mm, namely the thickness range of the annular waveguide layer along the direction, perpendicular to the outside, of the outer surface of the side wall is 0.1mm-10mm. A preferred value is 1mm.

The thickness of the annular waveguide layer is uniformly distributed, and the incident surface of the annular waveguide layer is parallel to the emergent surface.

The annular waveguide layer is made of silicon material.

Compared with the prior art, the invention has the main beneficial effects that:

the signal light collector can enhance the collimation collection of signal light in a larger range, and meanwhile, the outer-layer optical waveguide can be used for generating annular exciting light, so that the side effects of local overheating, overhigh energy density and tissue burning risk caused by the excitation of injected point-like light spots can be effectively reduced, and the excitation of the annular light spots is favorable for more efficient single-point signal collection at the center of the ring; the signal collection efficiency of the subcutaneous noninvasive detection equipment is improved, and the safety is good; the reliability and the accuracy of the optical noninvasive detection are further optimized. Through the regulation of size, change the size that printing opacity district size can set for cyclic annular facula, realize the signal light to reflecting the biological characteristics of the inside specific degree of depth position of organism, simple structure does benefit to and optimizes whole light path design, with low costs, sets up the convenience.

Drawings

Fig. 1 is a schematic diagram of spatial offset.

Fig. 2 is a schematic diagram of an optical excitation collecting structure according to a first embodiment of the invention.

Fig. 3 is a schematic view of an annular light spot and a central area according to a first embodiment of the invention.

Fig. 4 is a schematic diagram of a detection method according to a first embodiment of the invention.

Fig. 5 (a) is a schematic diagram of an optical excitation collection structure according to a second embodiment of the invention.

Fig. 5 (b) is a partial schematic view of an optical excitation collecting structure according to a second embodiment of the present invention, which relates to a signal light collector.

Fig. 6 is a schematic diagram of a signal light collector according to a second embodiment of the invention.

Detailed Description

The technical solutions in the specific embodiments of the present invention will be clearly and completely described below, and it should be understood that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention.

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings. In the figures, parts of the same structure or function are denoted by the same reference numerals, and not all parts shown are denoted by the associated reference numerals in all figures for reasons of clarity of presentation.

Example one

In the present embodiment, as shown in fig. 3 and 2, the optical excitation collecting structure of the signal light collector is provided to be integrated by one optical bin I-1, including a first optical path L1 and a second optical path L2; the first light path L1 is sequentially provided with a laser 1, an excitation fiber coupler 102, a conical lens 3 and a dichroic beam splitter element 6; the second optical path L2 is sequentially provided with a signal light collector 2, a dichroic beam splitter element 6, a band-pass filter component 7, a focusing component 4 and a detector 5; the excitation fiber coupler 102 is directly connected with the laser 1 through an optical fiber 101, light output by the laser 1 is converted into parallel light beams to enter the plane side of the conical lens 3, and light emitted from the convex surface of the conical lens 3 is annular light beams; the annular light beam irradiates the surface of a living body (taking the skin A as an example in the embodiment) through the first light path L1 to form an annular light spot Q; the signal light collector 2 of the present embodiment includes a reflection area 21, a transmission area 22, and an opening area 23; the signal light generated by the excitation of the annular light spot Q enters the second light path L2 from the light transmission region 22, is collimated by the reflection region 21, enters the focusing component 4 from the opening region 23, and is collected by the detector 5, and the signal light converged by the focusing component 4 is received by the optical fiber coupler 52 connected to the collection optical fiber bundle 51. The light-transmitting area 22 corresponds to a window formed in the optical bin I-1, and the central area C of the annular light spot is located inside the light-transmitting area 22. The central region C of the present embodiment is located at the center of the light-transmitting region 22. In this embodiment, taking the case that the signal light to be collected comes from subcutaneous tissue as an example, the distance D between the light-transmitting region 22 and the skin a to be measured ranges from 0.1mm to 10mm, and the preferred set value is 2mm.

In this embodiment, the excitation fiber coupler 102 is a single lens or a multi-lens structure, and the numerical aperture of the excitation fiber coupler 102 is 0.22. Optical fiber 101 is matched with excitation optical fiber coupler 102 to realize optical path connection, so that not only can parallel light beams be generated, but also optical path bending can be realized according to the actual structural design requirement. In the present embodiment, the output wavelength of the laser 1 is preferably 785nm or 830nm. The annular light spot Q is generated based on the conical lens 3, namely annular excitation is carried out, a central area C exists in the circle center position of the annular light spot, the spatial offset distance offset from the edge of the central area C to an excitation point (a point on the circumference of the annular light spot Q) is the same, signal light at the central area C reflects biological characteristic signals from organisms at the same depth level, the signals are accumulated to be high in intensity, efficient single-point signal collection is achieved at the central area C position of excitation of the annular light spot Q, and the risks of local overheating, overhigh energy density and tissue burning caused by injection of punctiform light spot excitation are effectively reduced. The surface of the reflective region 21 is made of a high-reflectivity material, and can deflect light entering the transparent region 22 within a certain angle range at the bottom of the signal light collector 2, and all the light is converted into parallel light beams parallel to the central axis of the signal light collector 2 to be output (i.e., the output light path is the second light path L2). It should be noted that the "certain angle range" is related to the receiving half angle θ of the signal light collector (refer to fig. 6), the specific signal light collector itself has a fixed receiving half angle, and when the signal light emitted from the skin a enters the signal light collector, a part of the light is not collimated by the reflection area 21 and cannot be received by the subsequent light path.

In the optical path structure design in this embodiment, the first optical path L1 and the second optical path L2 are partially overlapped, and a dichroic beam splitter 6 is disposed at the intersection of the two. The dichroic beam splitting element 6 used in the present embodiment is a dichroic mirror, and can turn the first optical path or the second optical path to perform beam splitting. The dichroic beam splitter 6 may be a dichroic member such as a dichroic film, a dichroic plate, or a dichroic beam splitter, and is not limited thereto. The exit light from the conical lens 3 is reflected above the opening area 23 while transmitting the signal light which exits from the opening area 23 and is collected by the collimation of the signal light collector, using the dichroic beam splitting element 6 in this embodiment. Specifically, the dichroic mirror turns the first optical path L1, reflects the annular light flux, which is incident at an angle of preferably 45 ° at the dichroic mirror, to the direction of the skin a, and transmits the signal light returning at the skin a. In the present embodiment, the reflection area 21 is a parabolic curved surface formed by rotating a parabola around the central axis N of the signal light collector; the optical center of the focusing element 4 is located on the central axis N. In other embodiments, the reflective region 21 is formed by two parabolic curved surfaces or by a plurality of non-smooth connected parabolic curved surfaces. The cross section of the opening area 23 may be an area having only two parallel edges or a rectangular and polygonal shape, and is not limited. A band-pass filter component 7 is arranged in front of the focusing component 4 along the second optical path L2 and is used for filtering stray light with a wavelength shorter than that of the signal light, and the central wavelength of the band-pass filter component 7 is matched with the wavelength of the laser. In the present embodiment, the band-pass filter member 7 is disposed on the second optical path L2 between the focusing member 4 and the dichroic beam splitting element 6. The collecting quality can be improved, the stray light is prevented from being collected as signal light, and the signal authenticity of the detector 5 is reduced. The numerical aperture of the focusing element 4 matches the reception half angle θ of the signal light collector (refer to fig. 6). The signal light collected from the opening area 23 can completely enter the focusing member 4, the collection loss is minimized, and the collection efficiency is good. The focusing element 4 in this embodiment comprises a focusing lens; the focal length of the focusing element 4 ranges from 5mm to 900mm. Of these, 50mm is preferred.

As shown in fig. 4, the detection method in this embodiment includes: the signal light collector adopting the embodiment includes: s1, determining a spatial offset distance according to a specific depth level of an organism to be detected; s2, forming an annular light beam by a parallel light beam generated by a laser through the conical lens, and irradiating a living body through a first light path to form an annular light spot, wherein the central area of the annular light spot is positioned in the light-transmitting area; s3, adjusting the annular excitation radius according to the space offset distance; and signal light generated by excitation is collimated by the reflecting area through the second light path and then collected to the detector for biological characteristic signal analysis.

In the step S3, after the annular excitation radius is adjusted to satisfy the spatial offset distance, the intensity of the collected signal light is controlled by changing the vertical distance between the opening area and the light-transmitting area on the central axis of the signal light collector. The signal light collector has a fixed receiving half angle, after the signal light emitted by the organism enters the light-transmitting area, a part of the signal light cannot be collimated by the reflecting area and cannot be received by a subsequent light path, and the receiving half angle can be changed by adjusting the vertical distance, so that the intensity of the collected signal light is influenced.

Example two

The main difference between the second embodiment of the present invention and the first embodiment is that, as shown in fig. 2, fig. 5 (a), fig. 5 (b), and fig. 6, an annular waveguide layer 8 is disposed along the outside of the parabolic curved surface of the reflection region 21 of the signal light collector, the annular light beam formed by the tapered lens 3 is coupled into the annular waveguide layer 8, and is completely converted into a parallel light beam parallel to the central axis and output from an annular exit surface Out, and an annular light spot Q is formed on the surface of the skin a for annular excitation. Compared with the ring excitation of the first embodiment, the signal light collector of the present embodiment forms the light beam of the conical lens 3 into a specific ring light beam. The distance from the central area C of the annular light spot Q to the annular excitation area can be determined by the size design of the signal light collector, that is, the radius of the annular light guide layer can be set according to the size of the spatial offset distance preset light transmission area 22 by the coincidence of the inner circle of the annular emergent surface Out and the edge of the light transmission area 22.

In the embodiment, the preset distance from the central region C to the annular excitation region, i.e. the radius of the light-transmitting region 22, is in the range of 0.1mm-10mm, wherein the preferred range is 2mm-5mm.

Wherein the thickness of the annular waveguide layer 8 in the direction perpendicular to and outward from said parabolic curved surface ranges from 0.1mm to 10mm. A preferred value is 1mm. In this embodiment, the annular waveguide layer 8 is made of silicon material, and may be specifically an annular optical fiber array or an annular transparent light guiding structure, which is not limited. In this embodiment, the thickness of the annular waveguide layer 8 is uniformly distributed, and the incident surface of the annular waveguide layer is parallel to the exit surface out. The intersection point of the plane of the incident surface of the annular waveguide layer 8 and the central axis N is not limited to being within the opening region 23 or being on the side of the opening region 23 away from the light-transmitting region 22.

For clarity of description, the use of certain conventional and specific terms and phrases is intended to be illustrative and not restrictive, but rather to limit the scope of the invention to the particular letter and translation thereof. It is further noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. The present invention has been described in detail, and the structure and operation principle of the present invention are explained by applying specific embodiments, and the above description of the embodiments is only used to help understanding the method and core idea of the present invention. It will be apparent to those skilled in the art that various changes and modifications can be made without departing from the principles of the invention, and it is intended to cover such changes and modifications as fall within the scope of the appended claims.

Claims (9)

1. A signal light collector, characterized by: the collector is provided with an upper opening and a lower opening, and the contour lines on two sides of the longitudinal section of the collector are parabolic line segments which are symmetrical about a central axis;

the collector comprises a reflection area on the inner surface, an opening area on the top surface and a transmission area on the bottom surface;

the area of the opening area is larger than that of the light-transmitting area; and the signal light transmitted by the light transmitting area is collimated by the reflecting area and then emitted out of the opening area in a parallel light beam manner.

2. A signal light collector as claimed in claim 1, wherein: the radius range of the light-transmitting area is 0.1mm to 10mm.

3. A signal light collector according to claim 1, wherein: the minimum width of the opening area is larger than the drift diameter length of the parabolic segment.

4. A signal light collector as claimed in claim 1, wherein: the entire inner surface of the collector is the reflective region.

5. A signal light collector according to claim 1, wherein: the reflecting surface of the reflecting area is made of mirror silver or polished mirror aluminum oxide.

6. A signal light collector according to any one of claims 1 to 5, wherein: the collector is a light collecting ring with an upper opening and a lower opening;

the light collecting ring is an annular waveguide, and light is transmitted to the emergent surface of the annular waveguide from the top to the bottom of the incident surface of the annular waveguide; the emergent surface and the bottom surface are in the same plane.

7. A signal light collector as claimed in claim 6, wherein: the thickness range of the annular waveguide is 0.1mm to 10mm.

8. A signal light collector as claimed in claim 6, wherein: the annular waveguide is made of silicon material.

9. A signal light collector as claimed in claim 6, wherein: the annular waveguide is an annular optical fiber array or an annular transparent light guide structure.

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