阅读说明：本技术 一种用于显微拉曼光谱仪的自动对焦系统及对焦方法 (Automatic focusing system and focusing method for micro-Raman spectrometer ) 是由 刘鸿飞 刘罡 彭万佳 于 2021-08-23 设计创作，主要内容包括：本发明提供了一种用于显微拉曼光谱仪的自动对焦系统及对焦方法,包括激光器、PSD位置传感器、数模转换器、处理器、步进电机与载物台；所述激光器发射激光照射位于载物台的样品上后反射至所述PSD位置传感器,所述PSD位置传感器将探测得的位置模拟信号传输给数模转换器转换为数字信号,所述数字信号经过处理器计算的得出样品的位置信息,并根据所述位置信息发送脉冲给所述步进电机带动所述载物台进行对焦。本发明利用PSD位置传感器实现显微拉曼的快速对焦功能。同时本发明响应速度快,无需复杂算法,硬件设计简单,1毫秒即可执行对焦操作。(The invention provides an automatic focusing system and a focusing method for a micro-Raman spectrometer, which comprise a laser, a PSD position sensor, a digital-to-analog converter, a processor, a stepping motor and an objective table, wherein the laser is arranged on the laser; the laser emits laser to irradiate a sample positioned on an objective table and then reflects the laser to the PSD position sensor, the PSD position sensor transmits a detected position analog signal to the digital-to-analog converter to be converted into a digital signal, the digital signal is calculated by the processor to obtain position information of the sample, and a pulse is sent to the stepping motor according to the position information to drive the objective table to focus. The invention realizes the rapid focusing function of micro-Raman by using the PSD position sensor. Meanwhile, the invention has fast response speed, does not need complex algorithm, has simple hardware design and can execute focusing operation within 1 millisecond.)

1. An automatic focusing system for a micro-Raman spectrometer is characterized by comprising a laser, a PSD position sensor, a digital-to-analog converter, a processor, a stepping motor and an objective table; the laser emits laser to irradiate a sample positioned on an objective table and then reflects the laser to the PSD position sensor, the PSD position sensor transmits a detected position analog signal to the digital-to-analog converter to be converted into a digital signal, the digital signal is calculated by the processor to obtain position information of the sample, and a pulse is sent to the stepping motor according to the position information to drive the objective table to focus.

2. The auto-focusing system for a focal microscopy raman spectrometer according to claim 1, wherein a double optical lens, a half-reflecting and half-transmitting mirror and an objective lens are further disposed between the laser and the stage; the laser emitted by the laser device changes direction through the double-optical lens, then transmits the laser through the semi-reflecting and semi-transmitting lens, and then is focused on a sample through the objective lens, and the light reflected by the sample is reflected to the PSD position sensor through the semi-reflecting and semi-transmitting lens.

3. The autofocus system of claim 1 or 2, wherein the processor is a single-chip microcomputer.

4. The autofocus system of claim 1 or claim 2, wherein the laser emits a 650nm laser beam.

5. An automatic focusing method for a micro-Raman spectrometer is characterized by comprising the following steps:

(1) emitting laser to a sample through a laser and then reflecting the laser to a PSD position sensor;

(2) the PSD position sensor transmits the detected position analog signal to a digital-to-analog converter to be converted into a digital signal;

(3) the digital signal is calculated by a processor to obtain the position information of the sample, and a pulse is sent to the stepping motor to drive the objective table to focus according to the position information.

6. The auto-focusing method for a focal microscopy raman spectrometer according to claim 5, wherein the step (1) comprises the steps of;

(a) the laser emitted by the laser device is changed in direction through the double-optical lens, then transmits through the semi-reflecting and semi-transmitting lens and is focused on a sample through the objective lens;

(b) and the light reflected by the sample is reflected to the PSD position sensor through the semi-reflecting and semi-transmitting mirror.

7. The method of claim 6, further comprising the steps of:

I₁、I₂the photoelectric currents of two electrodes of the PSD position sensor are respectively, when the focal plane of a sample is higher than the real focal point, the return optical path of laser is short, the laser reflected at the semi-reflecting and semi-transparent mirror is irradiated on the upper end of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＞I₂(ii) a When the focal plane of the sample is lower than the real focal point, the return optical path of the laser is longer, the laser reflected at the semi-reflecting and semi-transparent mirror is irradiated at the lower end of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＜I₂(ii) a When the focal plane of the sample is level with the real focal point, the laser reflected by the half-reflecting and half-transmitting mirror will strike the middle part of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＝I₂。

Technical Field

The invention relates to the technical field of micro-Raman spectroscopy, in particular to the technical field of automatic focusing of a micro-Raman spectrometer.

Background

At present, the types of micro-Raman on the market are very many, most of the micro-Raman are manually focused on samples, and only a few of the micro-Raman are focused on images by using a camera. As is well known, manual focusing requires that a coarse focusing screw is rotated to find an approximate position, and then a fine focusing screw is rotated to perform adjustment, which takes a lot of time; the camera carries out image processing algorithm for automatic focusing, the algorithm used by the method is complex, and an object with low recognition degree is difficult to find a correct focus, so that the limitation and the complexity of realizing the algorithm become the biggest difficult problem of camera focusing. Therefore, two existing focusing modes, one mode is slow, and the other mode is complex to realize and has limitations.

Disclosure of Invention

Based on the problems in the background art, the invention provides a design scheme for automatic focusing of a micro-Raman spectrometer on the basis of not increasing a complex algorithm and hardware design, and the scheme remarkably improves the automatic focusing performance of the micro-Raman spectrometer.

The invention adopts the following scheme:

an automatic focusing system for a micro-Raman spectrometer comprises a laser, a PSD position sensor, a digital-to-analog converter, a processor, a stepping motor and an objective table; the laser emits laser to irradiate a sample positioned on an objective table and then reflects the laser to the PSD position sensor, the PSD position sensor transmits a detected position analog signal to the digital-to-analog converter to be converted into a digital signal, the digital signal is calculated by the processor to obtain position information of the sample, and a pulse is sent to the stepping motor according to the position information to drive the objective table to focus.

Preferably, a double-optical lens, a half-reflecting and half-transmitting mirror and an objective lens are further arranged between the laser and the objective table; the laser emitted by the laser device changes direction through the double-optical lens, then transmits the laser through the semi-reflecting and semi-transmitting lens, and then is focused on a sample through the objective lens, and the light reflected by the sample is reflected to the PSD position sensor through the semi-reflecting and semi-transmitting lens.

Preferably, the processor is a single chip microcomputer.

Preferably, the laser emits a 650nm laser beam.

In addition, an automatic focusing method for the micro-Raman spectrometer is provided, which comprises the following steps:

(1) emitting laser to a sample through a laser and then reflecting the laser to a PSD position sensor;

(2) the PSD position sensor transmits the detected position analog signal to a digital-to-analog converter to be converted into a digital signal;

(3) the digital signal is calculated by a processor to obtain the position information of the sample, and a pulse is sent to the stepping motor to drive the objective table to focus according to the position information.

Preferably, the step (1) includes the steps of;

(a) the laser emitted by the laser device is changed in direction through the double-optical lens, then transmits through the semi-reflecting and semi-transmitting lens and is focused on a sample through the objective lens;

(b) and the light reflected by the sample is reflected to the PSD position sensor through the semi-reflecting and semi-transmitting mirror.

Preferably, the method further comprises the following steps:

I₁、I₂the photoelectric currents of two electrodes of the PSD position sensor are respectively, when the focal plane of a sample is higher than the real focal point, the return optical path of laser is short, the laser reflected at the semi-reflecting and semi-transparent mirror is irradiated on the upper end of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＞I₂(ii) a When the focal plane of the sample is lower than the real focal point, the return optical path of the laser is longer, the laser reflected at the semi-reflecting and semi-transparent mirror is irradiated at the lower end of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＜I₂(ii) a When the focal plane of the sample is level with the real focal point, the laser reflected by the half-reflecting and half-transmitting mirror will strike the middle part of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＝I₂。

By adopting the technical scheme, the invention can obtain the following technical effects: the invention realizes the rapid focusing function of micro-Raman by using the PSD position sensor. Meanwhile, the invention has fast response speed, does not need complex algorithm, has simple hardware design and can execute focusing operation within 1 millisecond.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a block diagram of a fast focus system employed by the present invention;

FIG. 2 is a schematic diagram of an auto-focus module according to the present invention.

In the figure: 1-a laser; 2-a bifocal lens; 3-half reflecting and half transmitting mirror; 4-an objective lens; 5-focal plane; 6. a PSD position sensor.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention more apparent, the technical solutions of the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings of the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention. Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the equipment or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

Examples

Referring to the attached figure 1 of the specification, an automatic focusing system for a micro-Raman spectrometer comprises a laser, a PSD position sensor, a digital-to-analog converter, a single chip microcomputer, a stepping motor and an objective table; the laser emits laser to irradiate a sample positioned on an objective table and then reflects the laser to the PSD position sensor, the PSD position sensor transmits a detected position analog signal to the digital-to-analog converter to be converted into a digital signal, the digital signal is calculated by the single chip microcomputer to obtain position information of the sample, and a pulse is sent to the stepping motor according to the position information to drive the objective table to focus.

The automatic focusing method of the automatic focusing system for the micro-Raman spectrometer comprises the following steps:

(1) the laser emits 650nm laser beams, and the laser beams are emitted to the sample through the laser and then reflected to the PSD position sensor;

(2) the PSD position sensor transmits the detected position analog signal to a digital-to-analog converter to be converted into a digital signal;

(3) the digital signal is calculated by a processor to obtain the position information of the sample, and a pulse is sent to the stepping motor to drive the objective table to focus according to the position information.

Referring to the attached figure 2 of the specification, a double-optical lens, a half-reflecting and half-transmitting lens and an objective lens are further arranged between the laser and the objective table; the laser emitted by the laser device changes direction through the double-optical lens, then transmits the laser through the semi-reflecting and semi-transmitting lens, and then is focused on a sample through the objective lens, and the light reflected by the sample is reflected to the PSD position sensor through the semi-reflecting and semi-transmitting lens. Therefore, the specific optical path part of the automatic focusing system for the micro-Raman spectrometer comprises the following steps;

(a) the laser emitted by the laser device is changed in direction through the double-optical lens, then transmits through the semi-reflecting and semi-transmitting lens and is focused on a sample through the objective lens;

(b) and the light reflected by the sample is reflected to the PSD position sensor through the semi-reflecting and semi-transmitting mirror.

The specific point path part of the automatic focusing system for the micro-Raman spectrometer comprises the following steps:

I₁、I₂the photoelectric currents of two electrodes of the PSD position sensor are respectively, when the focal plane of a sample is higher than the real focal point, the return optical path of laser is short, the laser reflected at the semi-reflecting and semi-transparent mirror is irradiated on the upper end of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＞I₂(ii) a When the focal plane of the sample is lower than the real focal point, the return optical path of the laser is longer, the laser reflected at the semi-reflecting and semi-transparent mirror is irradiated at the lower end of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＜I₂(ii) a When the focal plane of the sample is level with the real focal point, the laser reflected by the half-reflecting and half-transmitting mirror will strike the middle part of the PSD position sensor, and the analog signal output by the PSD position sensor is I₁＝I₂。

The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention.