CN107643275A - A kind of integral type Raman optical-mechanical system - Google Patents

Abstract

The invention provides a kind of integral type Raman optical-mechanical system, including semiconductor laser light resource, the first optical system, Volume Bragg grating, dichroic mirror, the second optical system, protecting window, long wave pass filter, the 3rd optical system, slit, dispersion compensation module, detector, analysis and processing module, semiconductor cooler, housing, photodetector, light source drive control module.The system of the present invention realizes Raman laser light source, Raman probe, spectrometer it is highly integrated, eliminate the Raman interference that the coupling loss between part and Transmission Fibers introduce, compact-sized, small volume, improve capacity usage ratio and the sensitivity of system.

Description

An integrated Raman optomechanical system

technical field

The invention relates to the technical field of optical equipment, in particular to an integrated Raman detection optical-mechanical system.

Background technique

Raman spectroscopy is widely used in the identification and detection of biological, mineral and chemical substances. The Raman optomechanical system based on Raman spectral analysis technology has good application prospects in the fields of food safety, biomedicine, public safety, material science, jewelry identification, geological prospecting, and environmental testing.

With the development of science and technology and the expansion of application requirements, the demand for miniaturization of Raman optomechanical systems is becoming stronger and stronger. The excitation light source used in the Raman optomechanical system is mostly an independently packaged light source module. The Raman signal excitation collection module and the Raman spectrum analysis module are usually separated from each other, and the modules are connected by transmission fibers. This structure limits the miniaturization of the Raman optical-mechanical system, and the coupling and docking of transmission fibers will cause loss and interference of optical signals, reducing the energy utilization and sensitivity of the system.

Contents of the invention

In order to overcome the deficiencies of the prior art, the object of the present invention is to provide a compact, highly integrated and miniaturized integrated Raman optical-mechanical system. It adopts the method of installing the semiconductor laser light source directly through the optical system and the long-wave pass filter and dispersion module in the housing, which simplifies the system structure and eliminates the influence and interference of the transmission fiber, which is beneficial to the miniaturization of the equipment and improves the efficiency. Performance of Raman optomechanical systems.

In order to achieve the above object, the technical solution adopted in the present invention is that it includes: semiconductor laser light source, first optical system, volume Bragg grating, dichroic mirror, second optical system, protective window, long-wave pass filter, third optical system , slit, dispersion module, detector, analysis and processing module, semiconductor cooler TEC, housing, photoelectric detector, light source drive control module.

Further, the first optical system, the volume Bragg grating, the dichroic mirror, the second optical system, and the protection window are sequentially arranged coaxially to form an excitation light path, and the laser light source is coaxially arranged at the front end of the excitation light path; the long-wave pass filter , the third optical system, and the coaxial arrangement of the slit constitute a collection optical path, which is placed perpendicular to the excitation optical path, and the dispersion module and the detector constitute a spectrum analysis optical path, which are located at the end of the collection optical path.

Further, the semiconductor laser light source is directly installed in the casing together with the long-wave filter and the dispersion module through the optical system without optical fiber coupling.

Further, the first optical system can realize collimation or spot shaping of the semiconductor laser light source, the second optical system (coupling and focusing the excitation light into the measured space, and the third optical system collects The Raman scattered light converges to the slit, and the dispersion module realizes the dispersion of the Raman spectrum, and transmits the separated spectral information to the detector.

Further, the positions of the first optical system and the volume Bragg grating can be interchanged.

Further, the semiconductor refrigerator (TEC) can control the semiconductor laser light source and the detector at the same time, or use the two TECs to control them separately.

Further, the light source drive control module is used to drive the semiconductor laser light source, and control the stability of the output power of the semiconductor laser light source through a feedback system composed of the photodetectors. The photodetector has a narrow-band filtering function, which can eliminate the influence of the Raman scattering spectrum on the signal received by the detector.

Further, the analysis and processing module is used to control the detector, and analyze and process the information received by the detector for system output.

The working principle of the present invention is: the light source drive control module drives and controls the laser light source to generate excitation light, and the excitation light passes through the first optical system, volume Bragg grating, dichromatic mirror, second optical system, and protective window in sequence, and the second optical system converts the excitation light Focusing on the measured sample, Raman scattering occurs after the measured sample is excited by the excitation light, and the generated Raman scattered light and Rayleigh scattered light pass through the protective window in the opposite direction and enter the Raman optical-mechanical system. The second optical system After being collected and passed through a dichroic mirror, the Rayleigh scattered light is filtered out by a long-wave pass filter, and the remaining Raman scattered light is converged onto the slit through a third optical system. After slit filtering, it enters the dispersion module to realize spectral separation, and after being received by the detector, the received signal is analyzed and processed by the subsequent analysis and processing module. The semiconductor refrigerator installed in the casing realizes the temperature control of the whole system.

After adopting the above-mentioned structure, the beneficial effects of the present invention are: reducing the pre-packaging process and structure of the laser light source, the excitation receiving module and the spectrum analysis module, significantly reducing the volume of the optical-mechanical system, and reducing the cost of the Raman optical-mechanical system; It adopts a unified structure of light source, excitation receiving module, and spectral analysis module, which improves the energy utilization rate of the light source, reduces the components in the equipment, further simplifies the equipment structure, reduces the cost, and is very conducive to the miniaturization of the equipment and the improvement of performance.

Description of drawings

FIG. 1 is a schematic diagram of an integrated Raman optomechanical system according to an embodiment of the present invention.

detailed description

According to the integrated Raman optical-mechanical system of the present invention, the structure includes: a semiconductor laser light source, a first optical system, a volume Bragg grating, a dichroic mirror, a second optical system, a protective window, a long-wave pass filter, a third optical system, Slit, dispersion module, detector, analysis and processing module, semiconductor cooler TEC, shell, photodetector, light source drive control module.

The first optical system, the volume Bragg grating, the dichroic mirror, the second optical system, and the protection window are arranged coaxially in sequence to form an excitation light path, and the laser light source is coaxially arranged at the front end of the excitation light path; the long-wave pass filter, the third The coaxial arrangement of the optical system and the slit constitutes a collection light path, which is placed perpendicularly to the excitation light path, and the dispersion module and the detector constitute a spectral analysis light path, which are located at the end of the collection light path.

The laser light source is a semiconductor laser or a light source capable of generating excitation light.

The dichroic mirror has a high transmittance to the excitation light and a high reflectance to the Raman scattered light generated by the sample to be measured. It transmits the excitation light forward in the optical path, transmits the Rayleigh scattered light back and reflects the Raman Scattered light.

The first optical system, the second optical system, and the third optical system can be spherical lenses, aspheric lenses, or spherical, aspheric lenses, cylindrical mirrors, prisms, etc.; The function is to realize the collimation or spot shaping of the semiconductor laser light source; the function of the second optical system is to couple and focus the excitation light to the measured space, and collect Raman scattering signals; the function of the third optical system is to converge the collected Raman scattered light to the slit. The dispersion module realizes the dispersion of the Raman spectrum, and transmits the separated spectrum information to the detector.

The protective window is coated with an anti-reflection film with high transmittance for both the excitation light and the Raman scattered light generated by the measured sample; its function is to seal and protect the Raman optical-mechanical system.

The positions of the first optical system and the volume Bragg grating can be interchanged.

The semiconductor refrigerator (TEC) can control the semiconductor laser light source and the detector at the same time, or use the two TECs to control them separately.

Further, the light source drive control module is used to drive the semiconductor laser light source, and control the stability of the output power of the semiconductor laser light source through a feedback system composed of the photodetectors. The photodetector has a narrow-band filtering function, which can eliminate the influence of the Raman scattering spectrum on the signal received by the detector.

Further, the analysis and processing module is used to control the detector, and analyze and process the information received by the detector for system output.

The working principle of this embodiment is: the light source driving control module controls the excitation light generated by the laser light source to pass through the first optical system, the volume Bragg grating, the dichroic mirror, the second optical system, and the protective window in sequence, and the second optical system focuses the excitation light on The sample to be tested, Raman scattering occurs after the sample is excited by the excitation light, and the generated Raman scattered light together with the Rayleigh scattered light enters the Raman optical mechanical system through the protective window in the opposite direction, and is collected by the second optical system. After passing through the dichroic mirror, the Rayleigh scattered light is filtered out by a long-wave pass filter, and the remaining Raman scattered light is converged onto the slit through a third optical system. After slit filtering, it enters the dispersion module. The dispersion module realizes the separation and transmission of the Raman spectrum, receives it through the detector, and processes the received signal through the subsequent analysis and processing module. The semiconductor refrigerator installed in the casing realizes the temperature control of the whole system. This embodiment can realize a high-performance, miniaturized Raman optical-mechanical system.

The above descriptions are only preferred embodiments of the patent of the present invention, and are not intended to limit the patent of the present invention. For those skilled in the art, the patent of the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the patent for the present invention shall be included within the protection scope of the patent for the present invention.

Claims (8)

1. a kind of integral type Raman optical-mechanical system, it is characterised in that it includes semiconductor laser light resource（101）, the first optical system （102）, Volume Bragg grating（103）, dichroic mirror (104), the second optical system (105), protecting window (106), the logical filter of long wave Mating plate (107), the 3rd optical system (108), slit（109）, dispersion compensation module（110）, detector（111）, analysis and processing module （112）、TEC（113）, housing（114）, photodetector（115）, light source drive control module（116）.

A kind of 2. integral type Raman optical-mechanical system according to claim 1, it is characterised in that first optical system （102）, Volume Bragg grating（103）, dichroic mirror (104), the second optical system (105), protecting window (106) is coaxial successively sets Put composition excitation light path, the coaxial front end for being arranged on excitation light path of LASER Light Source (101)；Long wave pass filter (107), the 3rd light System (108), slit（109）, it is coaxial set form collect light path, be disposed vertically with excitation light path, dispersion compensation module（110）、 Detector（111）Spectrum analysis light path is formed, positioned at the end for collecting light path.

A kind of 3. integral type Raman optical-mechanical system according to claim 1, it is characterised in that the semiconductor laser light resource （101）Without fiber coupling, directly pass through optical system and long wave pass filter (107), dispersion compensation module（110）Integrate together In housing（114）In, dry gas is full of in housing and is sealed.

A kind of 4. integral type Raman optical-mechanical system according to claim 1, it is characterised in that first optical system （102）The semiconductor laser light resource can be achieved（101）Collimation or spot shaping, second optical system（105）It will swash Luminous coupling, focus on detected space, the 3rd optical system（108）The Raman diffused light being collected into is converged to described narrow Seam（109）, the dispersion compensation module（110）The dispersion of Raman spectrum is realized, and the spectral information after separation is delivered to the spy Survey device（111）.

A kind of 5. integral type Raman optical-mechanical system according to claim 1, it is characterised in that first optical system （102）With Volume Bragg grating（103）Position can exchange.

6. a kind of integral type Raman optical-mechanical system according to claim 1, it is characterised in that it also includes being used for temperature control The semiconductor cooler of system（TEC）（113）, the semiconductor laser light resource can be controlled simultaneously（101）With the detector （111）, it is possible to use two TEC are controlled respectively.

A kind of 7. integral type Raman optical-mechanical system according to claim 1, it is characterised in that the light source drive control mould Block（116）For driving the semiconductor laser light resource（101）, and pass through the photodetector（115）The feedback system of composition System, controls the semiconductor laser light resource（101）The stability of power output；The photodetector（115）Filtered with arrowband Wave energy, influence of the raman scattering spectrum to detector reception signal can be eliminated.

A kind of 8. integral type Raman optical-mechanical system according to claim 1, it is characterised in that the analysis and processing module （112）For controlling detector（111）, and analyze and process the detector（111）The information received exports for system.