CN110702610B

Movatterモバイル変換

Info

Publication number: CN110702610B
Application number: CN201911003586.6A
Authority: CN
Inventors: 范元媛; 颜博霞; 邱乙耕; 齐月静; 马敬; 亓岩
Original assignee: Institute of Microelectronics of CAS
Current assignee: Institute of Microelectronics of CAS
Priority date: 2019-10-18
Filing date: 2019-10-18
Publication date: 2022-12-23
Anticipated expiration: 2039-10-18
Also published as: CN110702610A

Abstract

A device and photoacoustic spectrometer for balancing focusing power and spectral density of a rod-shaped light source are provided, the device comprises: the rod-shaped light source is a rod-shaped illuminant radiating like a blackbody; the collecting unit comprises a collecting mirror, one concave side of the collecting mirror is a collecting acting surface in a high-order aspheric surface shape, the collecting acting surface cover is arranged outside the rod-shaped light source, and a high-reflection metal film is arranged on the collecting acting surface and used for reflecting and focusing light emitted by the rod-shaped light source; and the shaping unit comprises a shaping mirror, the shaping mirror is arranged on one side opposite to the collection action surface, a shaping action surface in a high-order aspheric surface shape is convexly arranged on the shaping mirror, and an optical reflecting film is arranged on the shaping action surface and is used for selectively partially transmitting the light reflected by the collection action surface and realizing spectral density balance through spectral cutting. The invention simultaneously realizes the balanced output of the optical power spectral density and provides guarantee for the improvement of the subsequent detection sensitivity of the photoacoustic spectrum.

Description

Translated fromChinese

兼顾棒状光源聚焦功率及谱密度均衡的装置及光声光谱仪A device and a photoacoustic spectrometer that take into account the focusing power and spectral density balance of a rod-shaped light source

技术领域technical field

本发明涉及光声光谱仪技术领域，尤其涉及一种兼顾棒状光源聚焦功率及谱密度均衡的装置及光声光谱仪。The invention relates to the technical field of photoacoustic spectrometers, in particular to a device and a photoacoustic spectrometer that take into account both the focusing power of a rod-shaped light source and the balance of spectral density.

背景技术Background technique

随着电力、石化、核能、科研等迅速发展和环保工作不断加强，我国对气体化学成分监测检测仪器的需求越来越大、要求越来越高。高精度光声光谱检测仪是用于多组分气体在线监测和离线检测的高端通用仪器，具有检测精度高、多组分同时测量、无需载气、高稳定和易维护等优点，已逐步取代传统光学气体检测方法。红外光源是整个光声光谱检测系统的激励源，其特性好坏对系统灵敏度的影响举足轻重。With the rapid development of electric power, petrochemical, nuclear energy, scientific research, etc. and the continuous strengthening of environmental protection work, my country's demand for gas chemical composition monitoring and testing instruments is increasing and the requirements are getting higher and higher. The high-precision photoacoustic spectrometer is a high-end general-purpose instrument for on-line monitoring and off-line detection of multi-component gases. It has the advantages of high detection accuracy, multi-component simultaneous measurement, no carrier gas, high stability and easy maintenance. It has gradually replaced Traditional optical gas detection methods. The infrared light source is the excitation source of the entire photoacoustic spectroscopy detection system, and its characteristics have a significant impact on the sensitivity of the system.

非相干光源由于造价低、体积小、性能稳定，适用于结构紧凑的光声光谱仪。然而，由于非相干光源发散严重，存在光功率密度低、光束质量差且不易进行光束整形、聚焦等问题；同时，商用红外光源谱功率以6μm以下短波为主，长波段(10μm以后)光谱功率很低，存在功率谱密度不均衡的问题。一方面，需要提升系统总的光功率收集效率，以保证长波段光谱功率值；另一方面，高收集效率同时会造成短波段光谱功率过高的问题，进而影响光声系统灵敏度的提高。Incoherent light sources are suitable for compact photoacoustic spectrometers due to their low cost, small size and stable performance. However, due to the serious divergence of incoherent light sources, there are problems such as low optical power density, poor beam quality, and difficulty in beam shaping and focusing; at the same time, the spectral power of commercial infrared light sources is mainly short-wave below 6 μm, and the spectral power of long-wave (below 10 μm) Very low, there is a problem of unbalanced power spectral density. On the one hand, it is necessary to increase the total optical power collection efficiency of the system to ensure the long-wavelength spectral power value; on the other hand, high collection efficiency will also cause the problem of excessive short-wavelength spectral power, which will affect the improvement of the sensitivity of the photoacoustic system.

发明内容Contents of the invention

有鉴于此，本发明的主要目的在于提供了一种兼顾棒状光源聚焦功率及谱密度均衡的装置及光声光谱仪，以期至少部分地解决上述提及的技术问题中的至少之一。In view of this, the main purpose of the present invention is to provide a device and a photoacoustic spectrometer that take into account both the focusing power of a rod-shaped light source and the balance of spectral density, so as to at least partially solve at least one of the above-mentioned technical problems.

作为本发明的一个方面，提供了一种兼顾棒状光源聚焦功率及谱密度均衡的装置，包括：As an aspect of the present invention, a device that takes into account the focusing power and spectral density balance of a rod-shaped light source is provided, including:

棒状光源，为类黑体辐射的棒状发光体；Rod light source, which is a rod-shaped luminous body that radiates like a black body;

收集单元，包括收集镜，所述收集镜内凹的一侧为呈高阶非球面面型的收集作用面，所述收集作用面罩设于所述棒状光源外，且在所述收集作用面上设置有高反射金属膜，用于对所述棒状光源发出的光进行反射聚焦；The collection unit includes a collection mirror, the concave side of the collection mirror is a high-order aspherical collection surface, the collection surface is arranged outside the rod-shaped light source, and on the collection surface A highly reflective metal film is provided for reflecting and focusing the light emitted by the rod-shaped light source;

整形单元，包括整形镜，所述整形镜设置于收集作用面相对一侧，所述整形镜上凸设有呈高阶非球面面型的整形作用面，且在所述整形作用面上设置有光学反射膜，用于对所述收集作用面反射的光进行选择性部分透射，通过谱裁剪实现谱密度均衡。The shaping unit includes a shaping mirror, the shaping mirror is arranged on the opposite side of the collection action surface, the shaping mirror is provided with a shaping action surface in the form of a high-order aspheric surface, and the shaping action surface is provided with The optical reflective film is used for selectively partially transmitting the light reflected by the collection and action surface, and achieves spectral density balance through spectral clipping.

作为本发明的另一个方面，还提供了一种光声光谱仪，包括：As another aspect of the present invention, a kind of photoacoustic spectrometer is also provided, comprising:

如上述的兼顾棒状光源聚焦功率及谱密度均衡的装置，用于输出聚焦及谱密度均衡的光；As mentioned above, the device that takes into account the focusing power and spectral density balance of the rod-shaped light source is used to output focused and spectral density balanced light;

斩波器，设置于所述兼顾棒状光源聚焦功率及谱密度均衡的装置之后，用于对经过聚焦及谱密度均衡的光调制形成随时间断续的光；A chopper, arranged behind the device that takes into account the focusing power and spectral density balance of the rod-shaped light source, is used to modulate the focused and spectral density-balanced light to form intermittent light over time;

光声池，设置于所述整形单元的焦平面处，用于盛装样品，并接收经过所述斩波器调制的光。The photoacoustic cell is arranged at the focal plane of the shaping unit and is used to contain the sample and receive the light modulated by the chopper.

从上述技术方案可以看出，本发明提出的兼顾棒状光源聚焦功率及谱密度均衡的装置及光声光谱仪相对于现有技术至少具有以下有益效果其中之一或者其中一部分：It can be seen from the above technical solutions that the device and photoacoustic spectrometer proposed by the present invention, which take into account both the focusing power of the rod-shaped light source and the balance of spectral density, have at least one or part of the following beneficial effects compared with the prior art:

传统商用红外光源的收集镜多为标准抛物面或椭球面，适用于点光源能量等的收集；对于棒状红外光源，由于其非标准点光源，标准抛物面或椭球面无法实现最优收集效果；因此本发明针对棒状红外光源的特点，优化设计了高阶非球面收集镜模型，用于提升光声池入口处棒状红外光源聚焦总功率；此外，商用红外光源谱功率以6μm以下短波为主，长波段光谱功率很低，存在功率谱密度不均衡的问题，不利于光声光谱仪探测灵敏度的提高；本发明通过优化设计光路结构和光学元件，可以同时实现光功率谱密度的均衡输出，并可达到小型轻量的效果，为后续光声光谱仪探测灵敏度的提升提供保障；The collection mirrors of traditional commercial infrared light sources are mostly standard paraboloids or ellipsoids, which are suitable for collecting point light source energy; for rod-shaped infrared light sources, due to their non-standard point light sources, standard paraboloids or ellipsoids cannot achieve optimal collection effects; According to the characteristics of the rod-shaped infrared light source, the invention optimizes the design of a high-order aspheric collecting mirror model, which is used to increase the total focusing power of the rod-shaped infrared light source at the entrance of the photoacoustic pool; in addition, the spectral power of the commercial infrared light source is mainly short-wave below 6 μm, and the long-wave band The spectral power is very low, and there is a problem of unbalanced power spectral density, which is not conducive to the improvement of the detection sensitivity of the photoacoustic spectrometer; the invention can realize the balanced output of the optical power spectral density at the same time by optimizing the design of the optical path structure and optical components, and can achieve a small The lightweight effect provides a guarantee for the improvement of the detection sensitivity of the subsequent photoacoustic spectrometer;

本装置结构紧凑，简便快捷，操作方便，可靠性高。The device has the advantages of compact structure, simple and quick operation, convenient operation and high reliability.

附图说明Description of drawings

图1为本发明实施例的光路结构示意图；Fig. 1 is the schematic diagram of optical path structure of the embodiment of the present invention;

图2为本发明实施例提出的一种兼顾棒状红外光源聚焦功率及谱密度均衡装置的示意图；Fig. 2 is a schematic diagram of a rod-shaped infrared light source focusing power and spectral density equalization device proposed by an embodiment of the present invention;

图3为光谱功率分布图。Figure 3 is a graph of spectral power distribution.

上述附图中，附图标记含义如下：In the above accompanying drawings, the meanings of the reference signs are as follows:

020-收集单元；030-整形单元；110-红外光源；111-灯管固定区部分；112-灯管过渡区部分；113-灯管发热区部分；120-非球面收集镜；121-安装通孔；122-过渡通孔；123-非球面收集镜的反射面；124-固定螺纹孔；130-非球面整形镜；140-小孔光阑；150-功率探测器。020-Collection unit; 030-Shaping unit; 110-Infrared light source; 111-Lamp fixed area; 112-Lamp transition area; 113-Lamp heating area; 120-Aspherical collecting mirror; 121-Installation pass Hole; 122-transition through hole; 123-reflection surface of aspheric collecting mirror; 124-fixed threaded hole; 130-aspherical shaping mirror; 140-aperture diaphragm; 150-power detector.

具体实施方式detailed description

本发明针对棒状非相干红外光源的发散及功率谱密度不均的特性，提出一种同时兼顾聚焦功率及谱密度均衡的装置及光声光谱仪。本装置可以提高进入光声池的有效光功率，同时实现输出谱功率密度平坦化，有利于后续光声光谱仪光声检测灵敏度的提高。Aiming at the characteristics of divergence and uneven power spectral density of rod-shaped incoherent infrared light sources, the present invention proposes a device and a photoacoustic spectrometer that take into account both focusing power and spectral density balance. The device can increase the effective optical power entering the photoacoustic cell, and at the same time realize the flattening of the output spectral power density, which is beneficial to the improvement of the photoacoustic detection sensitivity of the subsequent photoacoustic spectrometer.

作为本发明的一个方面，提供一种兼顾棒状光源聚焦功率及谱密度均衡的装置，包括：As an aspect of the present invention, a device that takes into account the focusing power and spectral density balance of a rod-shaped light source is provided, including:

收集单元，包括收集镜，收集镜内凹的一侧为呈高阶非球面面型的收集作用面，收集作用面罩设于棒状光源外，且在收集作用面上设置有高反射金属膜，用于对棒状光源发出的光进行反射聚焦；The collection unit includes a collection mirror. The concave side of the collection mirror is a high-order aspherical collection surface. It is used to reflect and focus the light emitted by the rod light source;

整形单元，包括整形镜，整形镜设置于收集作用面相对一侧，整形镜上凸设有呈高阶非球面面型的整形作用面，且在整形作用面上设置有光学反射膜，用于对收集作用面反射的光进行选择性部分透射，通过谱裁剪实现谱密度均衡。The shaping unit includes a shaping mirror. The shaping mirror is arranged on the opposite side of the collection action surface. The shaping mirror is convexly provided with a high-order aspheric shaping action surface, and an optical reflection film is arranged on the shaping action surface for Selective partial transmission is carried out on the light reflected by the collecting surface, and the spectral density balance is realized by spectral clipping.

在解决光能收集等光学设计问题上，非成像光学系统优于成像光学系统，其设计主要是从光源的发光特性以及目标平面所要求的光强分布角度出发，以光能利用率作为设计指标，着重考虑能量传输过程中的匹配问题。在收集单元中，最重要的就是收集镜，本发明的设计目标是增大收集角，提高反射效率。由于红外辐射光源并非标准点光源，优化设计过程中引入高阶非球面模型。非球面光学元件是指面型由多项高次方程所决定且各点半径均不相同的光学元件。In solving optical design problems such as light energy collection, the non-imaging optical system is superior to the imaging optical system. Its design is mainly based on the luminous characteristics of the light source and the light intensity distribution required by the target plane, and the light energy utilization rate is used as the design index. , focusing on the matching problem in the energy transfer process. In the collection unit, the most important thing is the collection mirror, and the design goal of the present invention is to increase the collection angle and improve the reflection efficiency. Since the infrared radiation light source is not a standard point light source, a high-order aspheric model is introduced in the optimization design process. Aspherical optical elements refer to optical elements whose surface shape is determined by multiple high-order equations and whose radii are different for each point.

在本实施例中，本发明基于传输过程中光能量守恒的基本原理，结合传统红外光源的发光特点以及目标平面上的照度要求，并考虑斩波器等元件的尺寸和位置等参量，利用Zemax软件对非球面收集镜及非球面光学整形镜进行光源光束的整形聚焦优化设计，得到内凹为呈高阶非球面面型的收集作用面和外凸的呈高阶非球面面型的整形作用面。有效消除球差、像散、彗差、场曲等，还减少光能的损失、提高聚焦、准直精度，同时使系统轻量化、小型化。In this embodiment, the present invention is based on the basic principle of light energy conservation in the transmission process, combined with the luminous characteristics of traditional infrared light sources and the illumination requirements on the target plane, and considering parameters such as the size and position of components such as choppers, using Zemax The software optimizes the shaping and focusing of the light source beam on the aspheric collecting mirror and the aspheric optical shaping mirror, and obtains the concave collecting action surface that is a high-order aspheric surface and the shaping effect that is convex and a high-order aspheric surface noodle. Effectively eliminate spherical aberration, astigmatism, coma, curvature of field, etc., reduce light energy loss, improve focus and collimation accuracy, and make the system lightweight and miniaturized.

在本实施例中，本发明不仅对整形作用面和收集作用面的面型进行设计，还同时对非球面光学整形镜和收集镜进行镀膜以实现功率谱密度均衡和光功率聚焦。在收集作用面上设置有高反射金属膜，可以为但不局限于在其表面镀制相应的高反射金属膜；在整形作用面上设置有光学反射膜，可以为但不局限于在其表面镀制相应的光学反射膜，使其同时兼具整形聚焦和谱功率裁剪的作用，以达到小型轻量的效果。In this embodiment, the present invention not only designs the shape of the shaping surface and the collection surface, but also coats the aspheric optical shaping mirror and the collection mirror to achieve power spectral density balance and optical power focusing. A highly reflective metal film is provided on the collecting surface, which can be but not limited to a corresponding high reflective metal film plated on its surface; an optical reflective film is provided on the shaping surface, which can be but not limited to the surface The corresponding optical reflective film is plated to make it have the functions of shaping focus and spectral power cutting at the same time, so as to achieve the effect of small size and light weight.

在本实施例中，兼顾棒状光源聚焦功率及谱密度均衡的装置还包括孔径光阑；In this embodiment, the device that takes into account the focusing power and spectral density balance of the rod-shaped light source also includes an aperture stop;

孔径光阑，设置于整形单元的远离收集单元的一侧，用于限制经整形单元透射的光的光束口径，以使通过孔径光阑的光束能与斩波器相匹配。The aperture diaphragm is arranged on the side of the shaping unit away from the collection unit, and is used to limit the beam aperture of the light transmitted by the shaping unit, so that the light beam passing through the aperture diaphragm can match the chopper.

其中，在整形单元的焦平面处还可以设置功率探测器，用于对经过孔径光阑之后的光束进行能量收集探测，以检验兼顾棒状光源聚焦功率及谱密度均衡的装置输出的光束焦平面处的功率。Among them, a power detector can also be set at the focal plane of the shaping unit, which is used to collect and detect the energy of the beam passing through the aperture stop, so as to check the focal plane of the beam output by the device that takes into account the rod-shaped light source focusing power and spectral density balance. power.

在本实施例中，收集作用面的面型为二级偶次非球面抛物面；可以但不局限于，收集镜采用黄铜衬底材料。In this embodiment, the surface type of the collecting surface is a second-order even-order aspherical paraboloid; it is possible, but not limited to, that the collecting mirror is made of brass substrate material.

在本实施例中，整形镜上相对的两侧分别凸设有呈高阶非球面面型的整形作用面；作为优选，整形作用面的面型为二阶偶次非球面；作为优选，整形镜采用ZnSe衬底材料。In this embodiment, the opposite sides of the shaping mirror are respectively convexly provided with shaping action surfaces in a high-order aspheric surface; as a preference, the shape of the shaping action surface is a second-order even-order aspheric surface; as a preference, the shaping The mirror adopts ZnSe substrate material.

其中收集作用面的面型和整形作用面的面型通过Zemax光学仿真软件优化获得，在Zemax非序列模式下进行参数设置，光源根据实际光源特性选用圆柱体光源，目标使得焦平面处功率探测器功率达到最大，进而提升能量收集效率。Among them, the surface shape of the collection surface and the surface shape of the shaping surface are obtained through the optimization of Zemax optical simulation software. The parameters are set in Zemax non-sequential mode. The light source is selected according to the characteristics of the actual light source. The power is maximized, which in turn improves energy harvesting efficiency.

其中，针对不同强度的光源，可以但不局限于将整形镜上相对的两侧分别凸设有呈高阶非球面面型的整形作用面，以增强其选择透射的效果，更好的实现谱密度均衡。Among them, for light sources of different intensities, it is possible, but not limited to, to protrude the opposite sides of the shaping mirror with high-order aspheric shaping action surfaces to enhance its selective transmission effect and better achieve spectral Balanced density.

在本实施例中，整形作用面上的光学反射膜对谱成分为2-6μm的光束进行部分透射，透过率为20-40％；整形作用面上的光学反射膜对谱成分为6-10μm的光束进行部分透射，透过率为50-70％；整形作用面上的光学反射膜对谱成分为10-14μm的光束进行高透透射，透过率为80-99％。In this embodiment, the optical reflective film on the shaping surface partially transmits light beams with spectral components of 2-6 μm, and the transmittance is 20-40%; the optical reflective film on the shaping surface has a spectral component of 6-6 μm. The light beam of 10 μm is partially transmitted, and the transmittance is 50-70%; the optical reflection film on the shaping surface is highly transparent to the light beam with a spectral component of 10-14 μm, and the transmittance is 80-99%.

在本实施例中，设计一种棒状光源与收集单元固定的方式，但并不局限于此。In this embodiment, a way of fixing the rod-shaped light source and the collecting unit is designed, but it is not limited thereto.

其中，棒状光源背离收集作用面一端连接固定区：固定区，用于与收集镜进行固定连接。Wherein, the end of the rod-shaped light source facing away from the collecting surface is connected to the fixed area: the fixed area is used for fixed connection with the collecting mirror.

并且，收集单元还包括安装部，安装部与收集镜的收集作用面背对一侧相连；安装孔，设置于安装部上且贯穿收集镜，固定区置于安装孔内且与安装部固定连接；In addition, the collection unit also includes a mounting part, which is connected to the back-to-back side of the collecting surface of the collecting mirror; the mounting hole is arranged on the mounting part and runs through the collecting mirror, and the fixing area is placed in the mounting hole and fixedly connected to the mounting part ;

优选的，在安装部上设置固定螺纹孔，固定螺纹孔与安装孔相垂直连通；固定螺纹孔内螺接有一带外螺纹的固定件，用于固定固定区。Preferably, a fixing threaded hole is provided on the mounting part, and the fixing threaded hole is vertically connected with the mounting hole; a fixing member with an external thread is screwed inside the fixing threaded hole for fixing the fixing area.

在本实施例中，在棒状光源和固定区之间设置有过渡区，过渡区的直径小于固定区的直径；安装孔包括变径的安装通孔和过渡通孔，安装通孔和过渡通孔分别适配固定区和过渡区的安装。In this embodiment, a transition area is provided between the rod-shaped light source and the fixed area, and the diameter of the transition area is smaller than the diameter of the fixed area; the installation hole includes a variable-diameter installation through hole and a transition through hole, and the installation through hole and the transition through hole Suitable for installation in fixed area and transition area respectively.

其中，过渡区的直径小于固定区的直径，目的是为了尽量增大收集作用面的反射面积，提升功率收集效率。Wherein, the diameter of the transition zone is smaller than the diameter of the fixed zone, in order to maximize the reflection area of the collecting surface and improve the power collection efficiency.

作为本发明的另一方面，还提供一种光声光谱仪，包括：如上述兼顾棒状光源聚焦功率及谱密度均衡的装置，用于输出聚焦及谱密度均衡的光；斩波器，设置于所述兼顾棒状光源聚焦功率及谱密度均衡的装置之后，用于对经过聚焦及谱密度均衡的光调制形成随时间断续的光；以及光声池，设置于所述整形单元的焦平面处，用于盛装样品，并接收经过斩波器调制的光。As another aspect of the present invention, a photoacoustic spectrometer is also provided, including: the above-mentioned device that takes into account the focusing power and spectral density balance of the rod-shaped light source, and is used to output focused and spectral density balanced light; the chopper is arranged on the After the device that takes into account the focusing power and spectral density balance of the rod-shaped light source, it is used to form intermittent light over time for the light modulated through the focus and spectral density balance; and the photoacoustic pool is arranged at the focal plane of the shaping unit, using It is used to hold the sample and receive the light modulated by the chopper.

在本实施例中，孔径光阑的光束口径大小与斩波器的最大通光口径相同。In this embodiment, the beam aperture of the aperture stop is the same as the maximum aperture of the chopper.

为使本发明的目的、技术方案和优点更加清楚明白，以下结合具体实施例，并参照附图，对本发明作进一步的详细说明。In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

本发明的目的在于提供一种兼顾棒状红外光源聚焦功率及功率谱密度均衡的装置。The object of the present invention is to provide a device that takes into account both the focusing power of a rod-shaped infrared light source and the balance of power spectral density.

如图1所示，其中，图1为本发明的光路结构示意图。由红外光源110、收集单元020、整形单元030、小孔光阑140(即孔径光阑)、功率探测器150组成。由红外光源110发出的光束经过收集单元020和整形单元030整形聚焦后，经过小孔光阑140，最后入射到功率探测器150上；As shown in FIG. 1 , wherein FIG. 1 is a schematic diagram of the optical path structure of the present invention. It is composed of an infraredlight source 110 , a collectingunit 020 , ashaping unit 030 , an aperture stop 140 (namely an aperture stop), and apower detector 150 . The light beam emitted by the infraredlight source 110 is shaped and focused by thecollection unit 020 and theshaping unit 030, passes through theaperture diaphragm 140, and finally enters thepower detector 150;

红外光源110，为类黑体辐射的棒状发光结构；The infraredlight source 110 is a rod-shaped light-emitting structure similar to black body radiation;

收集单元020的反射面表面面型及整形单元030的表面面型通过Zemax光学仿真软件在非序列模式下优化获得，采取高阶非球面模型结构，目标使得功率探测器150功率达到最大，进而提升能量收集效率；The surface profile of the reflective surface of the collectingunit 020 and the surface profile of theshaping unit 030 are obtained through the optimization of the Zemax optical simulation software in the non-sequential mode, adopting a high-order aspheric model structure, and aiming to maximize the power of thepower detector 150, thereby improving energy harvesting efficiency;

收集单元020的反射面镀制高反射金属膜；The reflective surface of thecollection unit 020 is coated with a highly reflective metal film;

整形单元030的表面镀制相应的光学反射膜，同时兼具整形聚焦及谱功率裁剪的作用，以达到小型轻量的效果；The surface of theshaping unit 030 is coated with a corresponding optical reflection film, which also has the functions of shaping focusing and spectral power cutting, so as to achieve the effect of small size and light weight;

整形单元030的光学反射膜对高功率谱成分(如：2-6μm)部分透射，透过率为20-40％，进而降低相应部分透射功率；对低功率谱成分(如：6-14μm)高透透射，透过率为80-99％，进而实现谱裁剪效果，最终实现功率均衡输出；The optical reflection film of theshaping unit 030 partially transmits the high-power spectrum components (such as: 2-6 μm), and the transmittance is 20-40%, thereby reducing the corresponding part of the transmission power; for low-power spectrum components (such as: 6-14 μm) High transmittance, the transmittance is 80-99%, and then realize the spectrum clipping effect, and finally realize the power balanced output;

小孔光阑140用于限制通光光束口径，口径大小与所选斩波器最大通光口径相当；Theaperture diaphragm 140 is used to limit the aperture of the light beam, and the aperture size is equivalent to the maximum aperture of the selected chopper;

功率探测器150位于整形单元030的焦平面处，其有效面积小于等于后续光声池中心截面面积。Thepower detector 150 is located at the focal plane of theshaping unit 030, and its effective area is smaller than or equal to the central cross-sectional area of the subsequent photoacoustic cell.

本发明的兼顾棒状红外光源聚焦功率及谱密度均衡装置如图2所示。包括有：红外光源110、非球面收集镜120、非球面整形镜130、小孔光阑140、功率探测器150。其中，红外光源110由灯管固定区部分111(即固定区)、灯管过渡区部分112(即过渡区)、灯管发热区部分113(即棒状光源)组成。非球面收集镜120采用黄铜衬底材料，通过在截面直径为55mm的圆柱体(即安装部)上加工获得安装通孔121、过渡通孔122、非球面收集镜的反射面123(即收集作用面)、固定螺纹孔124。其中，安装通孔121与灯管固定区部分111尺寸匹配，通过固定螺纹孔124将二者相对位置固定；过渡通孔122与灯管过渡区部分112尺寸匹配。The focusing power and spectral density equalization device of the present invention is shown in FIG. 2 . It includes: an infraredlight source 110 , anaspheric collecting mirror 120 , anaspheric shaping mirror 130 , anaperture diaphragm 140 , and apower detector 150 . Wherein, the infraredlight source 110 is composed of a lamp tube fixing area 111 (ie, a fixed area), a tube transition area 112 (ie, a transition area), and a tube heating area 113 (ie, a rod-shaped light source). Theaspherical collecting mirror 120 adopts a brass substrate material, and thereflective surface 123 of the aspheric collecting mirror (i.e. collecting throughhole 121, transition throughhole 122, and aspheric collecting mirror) is obtained by processing on a cylinder (i.e. the mounting part) with a cross-sectional diameter of 55 mm. Acting surface), fixing threadedhole 124. Wherein, the installation throughhole 121 matches the size of the lamptube fixing area 111 , and the relative position of the two is fixed through the fixing threadedhole 124 ; the transition throughhole 122 matches the size of the lamptube transition area 112 .

灯管发热区部分113为类黑体辐射的棒状发光光源，尺寸为

辐射总光功率56W，主要辐射波长为2-14μm，辐射光谱为图3的(a)曲线所示的典型红外光源光谱功率分布；The heat-generatingarea part 113 of the lamp tube is a rod-shaped luminescent light source similar to black body radiation, and the size is

The total optical power of radiation is 56W, the main radiation wavelength is 2-14 μm, and the radiation spectrum is the typical infrared light source spectral power distribution shown in the curve (a) of Figure 3;

非球面收集镜120采用两部分通孔，安装通孔121尺寸为

过渡通孔122尺寸为

目的是为了尽量增大非球面收集镜的反射面123的反射面积，即增加收集面积，提升功率收集效率。Theaspherical collecting mirror 120 adopts two parts of through holes, and the size of the installation throughhole 121 is

The size of transition viahole 122 is

The purpose is to maximize the reflection area of thereflection surface 123 of the aspheric collection mirror, that is, to increase the collection area and improve the power collection efficiency.

非球面收集镜的反射面123表面镀制高反射金属膜。Thereflective surface 123 of the aspherical collecting mirror is plated with a highly reflective metal film.

非球面收集镜的反射面123表面面型及非球面整形镜130的表面面型通过Zemax光学仿真软件优化获得，目标使得焦平面处功率探测器150功率达到最大，进而提升能量收集效率。在Zemax非序列模式下进行参数设置，光源根据实际光源特性选用圆柱体光源。通过反复优化对比，并考虑实际加工可行性，非球面收集镜的反射面123采用二阶偶次非球面抛物面，非球面整形镜130采用二阶偶次非球面，对非相干红外光源的辐射能量进行收集。经优化后，聚焦点处功率探测器150上总功率为5.4W，比未优化前提升了约10倍，实现了红外光源能量的高效利用和功率提升。The surface profile of thereflective surface 123 of the aspheric collecting mirror and the surface profile of theaspheric shaping mirror 130 are obtained through optimization of the Zemax optical simulation software. The goal is to maximize the power of thepower detector 150 at the focal plane, thereby improving energy collection efficiency. The parameters are set in Zemax non-sequential mode, and the light source is a cylindrical light source according to the actual light source characteristics. Through repeated optimization and comparison, and considering the actual processing feasibility, thereflective surface 123 of the aspheric collecting mirror adopts a second-order even-order aspheric paraboloid, and theaspheric shaping mirror 130 adopts a second-order even-order aspheric surface. to collect. After optimization, the total power of thepower detector 150 at the focal point is 5.4W, which is about 10 times higher than that before optimization, realizing efficient utilization of infrared light source energy and power increase.

非球面整形镜130的表面镀有相应的光学反射膜，同时兼具整形聚焦及谱功率裁剪的作用，以达到小型轻量的效果；The surface of theaspheric shaping mirror 130 is coated with a corresponding optical reflection film, which also has the functions of shaping focusing and spectral power cutting, so as to achieve the effect of small size and light weight;

非球面整形镜130的表面光学反射膜对高功率谱成分(2-6μm)部分透射，透过率为30％±10％，进而降低相应部分透射功率；对低功率谱成分(6-14μm)高透透射，透过率为80-99％，进而实现谱裁剪效果，最终实现功率均衡输出，输出的光谱功率分布如图3的(b)曲线所示；The surface optical reflection film of theaspheric shaping mirror 130 partially transmits the high-power spectrum components (2-6 μm), and the transmittance is 30% ± 10%, thereby reducing the corresponding part of the transmission power; for the low-power spectrum components (6-14 μm) High transmittance, the transmittance is 80-99%, and then the spectrum clipping effect is realized, and finally the power balance output is realized. The output spectral power distribution is shown in the curve (b) of Figure 3;

镀膜非球面整形镜130的后表面与功率探测器150的距离要尽量紧凑短小，由于预留了后续光声池所需缓冲区的位置，在本实施例中距离取为47mm；The distance between the rear surface of the coatedaspheric shaping mirror 130 and thepower detector 150 should be as compact and short as possible. Since the position of the buffer zone required for the subsequent photoacoustic pool is reserved, the distance is taken as 47mm in this embodiment;

镀膜非球面整形镜130选用ZnSe衬底材料；The coatedaspheric shaping mirror 130 is made of ZnSe substrate material;

小孔光阑140用于限制通光光束口径，光束口径大小与所选斩波器最大通光口径相当，在本实施例中为32mm；Theaperture diaphragm 140 is used to limit the aperture of the light beam, which is equivalent to the maximum aperture of the selected chopper, which is 32mm in this embodiment;

功率探测器150位于整形单元130的焦平面处，其有效面积等于后续光声池中心截面面积，在本实施例中为8*8mm²。Thepower detector 150 is located at the focal plane of theshaping unit 130, and its effective area is equal to the central cross-sectional area of the subsequent photoacoustic cell, which is 8*8mm² in this embodiment.

以上的具体实施例，对本发明的目的、技术方案和有益效果进行了进一步详细说明，应理解的是，以上仅为本发明的具体实施例而已，并不用于限制本发明，凡在本发明的精神和原则之内，所做的任何修改、等同替换、改进等，均应包含在本发明的保护范围之内。The above specific embodiments have further described the purpose, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Within the spirit and principles, any modifications, equivalent replacements, improvements, etc., shall be included within the protection scope of the present invention.