A laser radar system without blind spots and atmospheric parameter detection method

Abstract

The present invention discloses a laser radar system without blind spots and an atmospheric parameter detection method, wherein the system comprises: a laser, a first polarization beam splitter, a polarization direction controller, a second polarization beam splitter, a first detector, a second detector and a processor; the optical path of the laser output light beam is the output light path; the polarization direction controller is arranged on the output light path; when the polarization direction controller is in a first state, the polarization direction of the laser output light beam is not changed, and when it is in a second state, the polarization direction of the light beam is rotated 90 degrees; the vertically polarized light beam reflected after atmospheric interaction is reflected to the first detector by the first polarization beam splitter; the parallel polarized light beam reflected back is converted into a vertically polarized light beam by the polarization direction controller in the second state, and then is reflected to the second detector by the second polarization beam splitter; in the whole process, the emission light beam and the reflected light beam are coaxial, so that the laser radar system can receive without blind spots.

Description

Technical Field

[0001] The present invention relates to the field of atmosphere detection, and in particular to a laser radar system without blind spots and an atmospheric parameter detection method. Background Art

[0002] Atmospheric sounding refers to the direct or indirect detection of the physical and chemical characteristics of the atmosphere with the help of various instruments and equipment. Atmospheric sounding can be divided into two categories according to the detection method: visual observation and instrumental measurement. Visual observation refers to observations made with the help of visual or auxiliary instruments, mainly by observers with the naked eye, and is mainly used in meteorological stations to observe clouds, visibility, weather phenomena and their evolution processes. Instrumental measurement is further divided into direct observation and remote sensing detection. Direct observation refers to placing the sensing element of the instrument directly in the atmosphere to be measured, and obtaining meteorological parameters describing the atmospheric conditions based on changes in the properties of the element, such as barometers, thermometers, hygrometers, etc.; remote sensing detection refers to the inversion of changes in meteorological elements in the atmosphere based on changes in signals during the propagation of electromagnetic waves in the atmosphere, such as laser meteorological radars.

[0003] As an active remote sensing technology, LiDAR obtains atmospheric parameters by emitting laser pulses to interact with atmospheric particles and receiving the resulting echo signals. Due to system design reasons, LiDAR in existing technologies often has blind spots ranging from tens to hundreds of meters, or even about 1 kilometer. LiDAR cannot measure parameters such as atmospheric molecules and aerosols in the blind spots. Summary of the invention

[0004] The object of the present invention is to provide a laser radar system without blind spots and an atmospheric parameter detection method, which can improve the above-mentioned problems.

[0005] The embodiment of the present invention is achieved as follows:

[0006] In a first aspect, the present invention provides a laser radar system without blind spots, comprising:

[0007] A laser, a first polarization beam splitter, a polarization direction controller, a second polarization beam splitter, a first detector, a second detector and a processor;

[0008] The optical path of the laser outgoing light beam is the outgoing light path;

[0009] The polarization direction controller is arranged on the outgoing light path, and the light beam reflected after the atmospheric interaction enters the polarization direction controller again;

[0010] When the polarization direction controller is in the first state, the polarization direction of the light beam emitted by the laser is not changed; when the polarization direction controller is in the second state, the polarization direction of the light beam reflected after atmospheric interaction is rotated 90 degrees. Parallel and vertical polarized light refer to light beams whose polarization directions are parallel and vertical to the optical path map, respectively.

[0011] The processor is electrically connected to the first detector and the second detector respectively.

[0012] It can be understood that the present invention discloses a laser radar system without blind spots, wherein when the polarization direction controller is in the first state, the light beam emitted by the laser transmits through the polarization direction controller, and is emitted to the atmosphere to react with the atmosphere; the light beam reflected back after the atmospheric interaction and perpendicular to the polarization direction of the emitted light beam is reflected to the first detector through the first polarization beam splitter. After the light beam parallel to the polarization direction of the emitted light beam passes through the first polarization beam splitter and the polarization direction controller in the second state, the polarization direction is rotated 90 degrees, and is reflected to the second detector by the second polarization beam splitter; the processor collects and inverts the two echo signals received, and calculates atmospheric parameters such as atmospheric molecules and aerosols. During the whole process, the emitted light beam and the reflected light beam are coaxial, realizing the blind spot-free reception of the laser radar system.

[0013] In an optional embodiment of the present invention, the laser radar system also includes a power supply, which is electrically connected to the laser, the first detector, the second detector and the polarization direction controller respectively.

[0014] It can be understood that the power supply can provide electrical energy to the laser, the first detector, the second detector and the polarization direction controller respectively.

[0015] In an optional embodiment of the present invention, the polarization direction controller is arranged between the first polarization beam splitter and the second polarization beam splitter on the outgoing light path, the first polarization beam splitter is used to reflect the light beam in a vertical polarization state, and the second polarization beam splitter is used to reflect the parallel polarized light beam after being rotated 90 degrees by the polarization direction controller;

[0016] It can be understood that the polarization direction controller can periodically control the polarization direction of the transmitted light.

[0017] In an optional embodiment of the present invention, when the laser starts to emit a light beam, the polarization direction controller is in a first state, and after the duration is the same as the pulse width of the laser, the polarization direction controller is in a second state.

[0018] In an optional embodiment of the present invention, a collimating lens is arranged between the laser and the polarization direction controller on the output light path.

[0019] It can be understood that the collimating lens is used to collimate the light beam emitted by the laser, so that the light beam emitted by the laser is collimated on the emission light path.

[0020] In an optional embodiment of the present invention, a projection lens assembly is further arranged after the polarization direction controller on the outgoing light path.

[0021] In an optional embodiment of the present invention, the blind-spot-free laser radar system also includes a first coupling lens; a first coupling lens is arranged on the optical path reflected from the polarization direction controller to the first detector, and the first coupling lens is used to couple the light beam reflected from the polarization direction controller into the first detector.

[0022] In an optional embodiment of the present invention, the blind-spot-free laser radar system also includes a second coupling lens; a second coupling lens is arranged on the optical path reflected from the polarization direction controller to the second detector, and the second coupling lens is used to couple the light beam reflected from the polarization direction controller into the second detector.

[0023] It can be understood that the first coupling lens and the second coupling lens are both converging lenses.

[0024] In a second aspect, the present invention further provides an atmospheric parameter detection method, comprising:

[0025] A laser is provided, wherein the optical path of an outgoing light beam of the laser is an outgoing light path;

[0026] A polarization direction controller is provided, which is arranged on the output light path, and the light beam reflected after atmospheric interaction enters the polarization direction controller again; when the polarization direction controller is in a first state, the polarization direction of the light beam emitted by the laser is not changed; when the polarization direction controller is in a second state, the polarization direction of the light beam reflected after atmospheric interaction is rotated 90 degrees.

[0027] A first polarization beam splitter and a second polarization beam splitter are provided to reflect parallel polarized light and transmit perpendicular polarized light.

[0028] Providing a first detector and a second detector to receive signals reflected from the first and second polarization beam splitters respectively;

[0029] A processor is provided, and the processor is electrically connected to the first detector and the second detector respectively.

[0030] In an optional embodiment of the present invention, the atmospheric parameter detection method further includes:

[0031] The polarization direction controller comprises a first polarization beam splitter and a second polarization beam splitter which are sequentially arranged in the middle of the outgoing light path, wherein the first polarization beam splitter is used to reflect a light beam in a vertical polarization state, and the second polarization beam splitter is used to reflect a parallel polarized light beam after being rotated 90 degrees by the polarization direction controller;

[0032] When the laser starts to emit a light beam, the polarization direction controller is in a first state, and the duration is the same as the pulse width of the laser; thereafter, the polarization direction controller is in a second state.

[0033] Beneficial effects:

[0034] The present invention discloses a laser radar system without blind spots, wherein when the polarization direction controller is in the first state, the light beam emitted by the laser transmits through the polarization direction controller, and is emitted to the atmosphere to react with the atmosphere without changing the polarization direction; when the polarization direction controller is in the second state, the light beam reflected after the atmospheric interaction is reflected to the first detector and the second detector respectively; the processor collects and inverts the two received echo signals, and calculates atmospheric parameters such as atmospheric molecules and aerosols. In the whole process, the emission light beam and the reflected light beam are coaxial, realizing the laser radar system without blind spots.

[0035] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0037] Figure 1 It is a structural schematic diagram of a laser radar system without blind spots provided by the present invention;

[0038] Figure 2 The present invention is a flow chart of an atmospheric parameter detection method provided by the present invention.

[0039] Figure Number:

[0040] Laser 10, polarization direction controller 20, first polarization beam splitter 21, second polarization beam splitter 22, first detector 31, second detector 32, processor 40, collimating lens 50, projection lens assembly 60, first coupling lens 71, second coupling lens 72, power supply 80. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] like Figure 1 As shown, the present invention provides a laser radar system without blind spots, which includes: a laser 10, a first polarization beam splitter 21, a polarization direction controller 20, a second polarization beam splitter 22, a first detector 31, a second detector 32 and a processor 40.

[0043] The optical path of the light beam emitted by the laser 10 is the emission light path; a polarization direction controller 20 is arranged on the emission light path, and the polarization direction controller 20 is in a first state and does not change the polarization direction of the light beam emitted by the laser 10; the vertically polarized light beam reflected after atmospheric interaction is reflected by the first polarization beam splitter 21 to the first detector 31; the reflected parallel polarized light beam is converted into a vertically polarized light beam by the polarization direction controller 20 in a second state, and then reflected by the second polarization beam splitter 22 to the second detector 32; the processor 40 is electrically connected to the first detector 31 and the second detector 32, respectively.

[0044] It can be understood that the present invention discloses a laser radar system without blind spots, wherein when the polarization direction controller 20 is in the first state, the light beam emitted by the laser 10 transmits through the polarization direction controller 20 without changing the polarization direction, and is emitted to the atmosphere to interact with the atmosphere; the vertically polarized light beam reflected after the atmospheric interaction is reflected by the first polarization beam splitter 21 to the first detector 31; the reflected parallel polarized light beam is converted into a vertically polarized light beam by the polarization direction controller 20 in the second state, and is reflected by the second polarization beam splitter 22 to the second detector 32; the processor 40 collects and inverts the two received echo signals, and calculates atmospheric parameters such as atmospheric molecules and aerosols. In the whole process, the emission light beam and the reflected light beam are coaxial, realizing the laser radar system without blind spots.

[0045] In an optional embodiment of the present invention, the laser radar system further includes a power supply 80, which is electrically connected to the laser 10, the first detector 31, the second detector 32 and the polarization direction controller 20 respectively.

[0046] It can be understood that the power supply 80 can provide electrical energy to the laser 10, the first detector 31, the second detector 32 and the polarization direction controller 20 respectively.

[0047] In an optional embodiment of the present invention, the polarization direction controller is arranged between the first polarization beam splitter and the second polarization beam splitter on the outgoing light path, the first polarization beam splitter is used to reflect the light beam in a vertical polarization state, and the second polarization beam splitter is used to reflect the parallel polarized light beam after being rotated 90 degrees by the polarization direction controller;

[0048] It can be understood that the polarization direction controller can periodically control the polarization direction of the transmitted light.

[0049] In an optional embodiment of the present invention, when the laser starts to emit a light beam, the polarization direction controller is in a first state, and the duration is the same as the pulse width of the laser; thereafter, the polarization direction controller is in a second state. In an optional embodiment of the present invention, a collimating lens 50 is provided between the laser 10 and the polarization direction controller 20 on the outgoing light path.

[0050] It can be understood that the collimating lens 50 is used to collimate the light beam emitted by the laser 10, so that the light beam emitted by the laser 10 is collimated on the emission light path.

[0051] In an optional embodiment of the present invention, a projection lens assembly 60 is further arranged after the polarization direction controller 20 on the outgoing light path.

[0052] In an optional embodiment of the present invention, a first coupling lens 71 is provided on the optical path reflected from the polarization direction controller 20 to the first detector 31 , and the first coupling lens 71 is used to couple the light beam reflected from the polarization direction controller 20 into the first detector 31 .

[0053] In an optional embodiment of the present invention, a second coupling lens 72 is provided on the optical path reflected from the polarization direction controller 20 to the second detector 32 , and the second coupling lens 72 is used to couple the light beam reflected from the polarization direction controller 20 into the second detector 32 .

[0054] It can be understood that the first coupling lens 71 and the second coupling lens 72 are both converging lenses.

[0055] Another embodiment of the present invention further provides an atmospheric parameter detection method, which is applicable to the laser radar system without blind spots involved in the aforementioned embodiments of the present invention, and the atmospheric parameter detection method comprises the following steps:

[0056] S1, providing a laser, wherein the optical path of the laser output light beam is the output light path.

[0057] S2, providing a polarization direction controller, which is arranged on the output light path, and the light beam reflected after atmospheric interaction enters the polarization direction controller again; when the polarization direction controller is in the first state, the polarization direction of the light beam emitted by the laser is not changed; when the polarization direction controller is in the second state, the polarization direction of the light beam reflected after atmospheric interaction is rotated 90 degrees.

[0058] S3, providing a first polarization beam splitter and a second polarization beam splitter to reflect parallel polarized light and transmit vertical polarized light.

[0059] S4, providing a first detector and a second detector, wherein the light beam reflected back after the atmospheric interaction and perpendicular to the polarization direction of the outgoing light beam is reflected to the first detector by the first polarization beam splitter. After the light beam parallel to the polarization direction of the outgoing light beam passes through the first polarization beam splitter and the polarization direction controller in the second state, the polarization direction of the light beam is rotated 90 degrees and is reflected to the second detector by the second polarization beam splitter;

[0060] S5, provide a processor, wherein the processor is electrically connected to the first detector and the second detector respectively.

[0061] It should be noted that other components of the laser radar system without blind spots that are not involved in this embodiment can be referred to as described in the previous embodiments of the present invention, and will not be repeated here for the sake of brevity.

[0062] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A laser radar system without blind spots, characterized in that: include: A laser, a first polarization beam splitter, a polarization direction controller, a second polarization beam splitter, a first detector, a second detector and a processor; The optical path of the laser outgoing light beam is the outgoing light path; The polarization direction controller is arranged on the outgoing light path, and the light beam reflected after the atmospheric interaction enters the polarization direction controller again; The first polarization beam splitter and the second polarization beam splitter reflect parallel polarized light and transmit perpendicular polarized light; The processor is electrically connected to the first detector and the second detector respectively; The laser radar system also includes a power supply, which is electrically connected to the laser, the first detector, the second detector and the polarization direction controller respectively; When the polarization direction controller is in the first state, the polarization direction of the light beam emitted by the laser is not changed; When the polarization direction controller is in the second state, the polarization direction of the parallel polarized light beam reflected after the atmospheric interaction is rotated by 90 degrees, and is reflected to the second detector through the second polarization beam splitter; When the laser starts to emit a light beam, the polarization direction controller is in a first state, and after the duration is equal to the pulse width of the laser, the polarization direction controller is in a second state; A collimating lens is arranged between the laser and the polarization direction controller on the output light path; A projection lens assembly is also arranged after the polarization direction controller on the outgoing light path; The laser radar system without blind spots also includes a first coupling lens; A first coupling lens is arranged on the optical path reflected from the polarization direction controller to the first detector, and the first coupling lens is used to couple the light beam reflected from the polarization direction controller into the first detector; The laser radar system without blind spots also includes a second coupling lens; A second coupling lens is arranged on the optical path reflected from the polarization direction controller to the second detector, and the second coupling lens is used to couple the light beam reflected from the polarization direction controller into the second detector.

2. A method for detecting atmospheric parameters, characterized in that: include: A laser is provided, wherein the optical path of an outgoing light beam of the laser is an outgoing light path; A polarization direction controller is provided, and the polarization direction controller is arranged on the outgoing light path, and the light beam reflected after the atmospheric interaction enters the polarization direction controller again; When the polarization direction controller is in the first state, the polarization direction of the light beam emitted by the laser is not changed; When the polarization direction controller is in the second state, the polarization direction of the light beam reflected after the atmospheric interaction is rotated by 90 degrees; Providing a first polarization beam splitter and a second polarization beam splitter to reflect parallel polarized light and transmit perpendicular polarized light; Providing a first detector and a second detector to receive signals reflected from the first and second polarization beam splitters respectively; providing a processor, the processor being electrically connected to the first detector and the second detector respectively; The atmospheric parameter detection method further comprises: the polarization direction controller is arranged between a first polarization beam splitter and a second polarization beam splitter on the outgoing light path, the first polarization beam splitter is used to reflect a light beam in a vertical polarization state, and the second polarization beam splitter is used to reflect a parallel polarized light beam rotated 90 degrees by the polarization direction controller; The atmospheric parameter detection method is applicable to the blind-spot-free laser radar system according to claim 1.

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