CN108180994B - Full-view field visible light near infrared lightning spectrum detector - Google Patents
Full-view field visible light near infrared lightning spectrum detector Download PDFInfo
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Abstract
The invention discloses a full-view field visible light near-infrared lightning spectrum detector, which comprises observation equipment and data processing equipment, wherein the observation equipment comprises an instrument shell, an optical module and an acoustic module; the instrument shell comprises an upper light shielding plate, an annular transparent glass protecting cover, a light shielding bottom plate, a hemispherical transparent glass protecting cover and an annular rain shielding plate, wherein a round hole is formed in the center of the upper light shielding plate; the shading bottom plate is disc-shaped, and a bracket adapter is arranged in the center of the lower part of the shading bottom plate; the annular transparent glass protective cover surrounds the edge of the shading bottom plate and is fixed above the shading bottom plate; the upper light shielding plate is arranged above the transparent glass protective cover, and a round hole is formed in the center of the upper light shielding plate so that the fisheye wide-angle lens is completely exposed; the optical module comprises eight identical transmission gratings, eight identical industrial CCD cameras and a full-sky imager; eight industrial CCD cameras are arranged in a ring shape at an interval of 45 degrees; the all-sky imager is arranged in the center above the shading bottom plate through a fixed bracket; the acoustic module includes a sound receiver.
Description
Technical Field
The invention belongs to the field of meteorological monitoring equipment, and particularly relates to a full-view field visible light near-infrared lightning spectrum detector.
Background
Lightning is a discharge phenomenon in the atmosphere and can produce electromagnetic radiation, optical radiation, shock waves and other effects. Among them, the strong luminescence of the lightning channel is one of the most remarkable characteristics, and the earliest recognition of lightning physics comes from optical observation. At present, optical observation means directly shoot optical images by using traditional or digital cameras, and further shoot and acquire spectral image information by advanced equipment such as a spectrograph.
By researching the optical image information of the lightning channel, the characteristics of the lightning development speed, the duration time, the morphological structure of the channel, the brightness change and the like can be measured. Among them, the rotating streak camera of Boys (1926) invention has a milestone meaning for deepening the understanding of the lightning discharge process. Boys symmetrically installs the lens of high-speed shooting at the diameter both ends of a rotatory disc, and the lens is rotatory along with the disc high-speed, later improves into the lens motionless again, and the film is rotatory at a high speed. The lightning image shot by the Boys camera is displayed as bright stripes which can be clearly distinguished in time, and the evolution of the lightning channel along with time can be clearly displayed. The students reveal through a Boys camera that the negative pilot of the thunder and lightning propagates according to the cascade form, and the positive pilot approximately continuously develops the basic structural characteristics of cloud-to-ground flash. With the rapid development of recent electronic technology, the space-time resolution of the high-speed camera is remarkably improved, and the digital high-speed camera with excellent performance enables students to study the development and evolution of a lightning channel more finely.
The lightning channel consists of highly ionized plasma, and the spectral information of the lightning channel can reflect the basic physical characteristics of the channel such as temperature, electron concentration, conductivity and the like. As early as the late 19 th century, spectral identification became an important tool for studying lightning. The Hersche (1868) first identified that the nitrogen line of the lightning discharge is the brightest line in the visible band, and the relative intensities of the lines vary from spectrum to spectrum. Slipher (1917) obtained a photographic record of the first lightning spectrum. Dufay (1949) first proposed that lightning spectrum can quantitatively reflect the physical conditions of lightning channels and surroundings. 7 months in 2012, cen Jian Yong et al (2014) recorded the spectrum of the ball-shaped lightning for the first time, and analyzed the ball-shaped lightning to contain soil elements. More and more students obtain important knowledge of the discharge characteristics of the lightning channel by researching the lightning spectrum.
At present, many inventions and innovations are provided by a plurality of people in lightning optical observation application, and many inventions and innovations are patented. For example, liu Mingyuan (ZL 201410099449.8) proposes a lightning high-speed photometer, wherein the data transmission capability of a CCD is improved by using an optical fiber bundle; li Xiang (zl 201420703008. X) proposes a temperature testing device for a lightning channel, wherein the temperature of the lightning channel is inverted by the relative intensity of spectral lines of an infrared band spectrum and a visible band spectrum emitted by the lightning channel; liu Chen et al (ZL 201310076766.3) propose a lightning detection device that uses lightning light signals for monitoring the lightning activity. However, there are few practical applications of lightning channel spectrum information, and spectrum research is still mainly used for scientific research purposes, and direct-shooting channel optical images are still mainly used in practical applications. Therefore, the full-view field visible light near infrared lightning spectrum detection device provided by the invention can well make up for the blank of the spectrum in practical application. The invention combines the optical image and spectrum information of the lightning channel to monitor the lightning activity and provide the basic physical parameters such as temperature, electron concentration, conductivity and the like of the lightning channel.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a full-view field visible light near infrared lightning spectrum detector.
The above object of the present invention is achieved by the following technical solutions:
the full-view field visible light near-infrared lightning spectrum detector comprises observation equipment and data processing equipment, wherein the observation equipment comprises an instrument shell, an optical module and an acoustic module;
the instrument shell comprises an upper light shielding plate, an annular transparent glass protecting cover, a light shielding bottom plate, a hemispherical transparent glass protecting cover and an annular rain shielding plate, wherein a round hole is formed in the center of the upper light shielding plate; the shading bottom plate is disc-shaped, and a bracket adapter used for fixing the mounting bracket is arranged in the center below the shading bottom plate; the annular transparent glass protective cover surrounds the edge of the shading bottom plate and is fixed above the shading bottom plate; the upper light shielding plate is arranged above the transparent glass protective cover, and a round hole is formed in the center of the upper light shielding plate so that the fisheye wide-angle lens is completely exposed; a hemispherical transparent glass protective cover for protecting the fisheye wide-angle lens is arranged above the central round hole of the upper light shielding plate; the annular rain shield surrounds the edge arranged below the shading bottom plate;
the optical module comprises eight identical transmission gratings, eight identical industrial CCD cameras and a full-sky imager; the transmission grating is arranged on the shading bottom plate through a grating bracket and is arranged close to the front end of the lens; each industrial CCD camera consists of a lens and an industrial CCD camera body, and is arranged on a shading bottom plate through a fixed bracket, and eight industrial CCD cameras are arranged in a ring shape at an interval of 45 degrees; the full-sky imager comprises a fish eye wide-angle lens and a corresponding full-sky imaging CCD camera body, and is arranged at the right center above the shading bottom plate through a fixed bracket;
the acoustic module comprises a sound receiver which is arranged below the shading bottom plate through a fixed bracket.
Further, a heat radiation fan is arranged on the back surface of the shading bottom plate.
Further, two identical cooling fans are symmetrically arranged on the back surface of the shading bottom plate.
Further, the acoustic module comprises two identical high-sensitivity sound receivers symmetrically arranged below the shading base plate through a fixed bracket.
Further, the field of view of each industrial grade CCD camera is 95 °.
Further, the data processing device comprises a data acquisition module, a storage module, a control module and a data processing module.
Further, the control module is a computer or a singlechip.
The invention has the advantages that:
(1) According to the invention, the visual fields of eight annular evenly-installed industrial CCD cameras are mutually overlapped, so that a panoramic image when lightning occurs can be provided, and simultaneously, an all-sky imager is matched, so that an all-visual field optical image when a lightning event occurs can be finally obtained;
(2) The invention realizes automatic continuous observation of lightning events, and can realize automatic continuous recording of independent events through external trigger, and automatic continuous recording of optical characteristics;
(3) The invention can record and analyze the spectrum information of the visible light and near infrared wave bands of the lightning channel, and can obtain the parameters such as the temperature, the electron density, the conductivity and the like of the lightning channel from the spectrum information, thereby being beneficial to scientific monitoring and research of lightning activity;
(4) The invention has compact structure, wide monitoring range, high detection efficiency, low power, energy conservation and environmental protection.
Drawings
Fig. 1 is a schematic top view of the internal structure of the present invention with the light shield 7 and hemispherical transparent glass protection cover 10 removed. Wherein, 1 is transmission grating, 2 is the camera lens, 3 is industrial CCD camera fuselage, 4 is fish-eye wide-angle lens, 5 is full sky imaging CCD camera fuselage, 8 is annular transparent glass safety cover, 9 is shading bottom plate. Wherein 2 and 3 constitute industrial CCD cameras, and 4 and 5 constitute an all-sky imager.
Fig. 2 is a schematic cross-sectional side view of the structure of the present invention. Wherein 6 is a high-sensitivity sound receiver, 7 is an upper light shielding plate with a round hole in the center, 10 is a hemispherical transparent glass protection cover, 11 is a grating bracket, 12 is a camera fixing bracket, 13 is a cooling fan, and 15 is an annular rain shielding plate. Wherein 7, 8, 9, 10 and 15 constitute the protective enclosure of the instrument.
Fig. 3 is a schematic bottom view of the structure of the present invention. Wherein 14 is a bracket interface.
Fig. 4 is a schematic of the workflow of the present invention.
Fig. 5 is a diffraction schematic of a transmission grating in which the present invention operates. Wherein θ is the incident angle, ψ is the diffraction angle, and the point a is the light spot position on the CCD through the lens after the light beam of wavelength λ is diffracted by the transmission grating.
Fig. 6 is a schematic diagram of a 360 deg. field of view stitching by a CCD camera. Wherein, (1) - (8) are fields of view of the corresponding-position industrial-grade CCD cameras in FIG. 2. Wherein, (a) is a schematic view of eight 95-degree fields of view spliced into 360-degree fields of view, and (b) is a schematic view of 95-degree fields of view of a single industrial-grade CCD camera.
Fig. 7 is a panoramic view of the photograph of the present invention.
FIG. 8 is a schematic diagram of locating lightning channels using acousto-optic time differences of arrival. Wherein N is in the northbound direction, E is in the eastern direction; o is the center of the instrument, P is the spot recorded in the field of view, its azimuth is γ, and its distance from the instrument is L. Wherein (a) is an image obtained by direct shooting of an all-sky imager, and (b) is an image obtained by distortion correction of (a).
Fig. 9 is a full sky schematic of the present invention.
FIG. 10 is a schematic representation of spectral lines obtained in accordance with the present invention.
Detailed Description
The following describes the essential aspects of the invention in detail with reference to the drawings and examples, but is not intended to limit the scope of the invention.
The full-view field visible light near infrared spectrum detector provided by the invention is mainly divided into two parts: an observation device and a data processing device. Wherein, the observation equipment is installed in an external open environment and is responsible for observing the lightning process. The data processing equipment is connected with the observation equipment through a communication cable and is responsible for collecting, storing and inverting calculation of the observed lightning data.
Fig. 1, fig. 2 and fig. 3 respectively show a specific structure of an observation device part of the full-view field visible near infrared lightning spectrum detector, which is provided by the invention, and mainly comprises an instrument shell, an optical module and an acoustic module. Specifically, as shown in the figure, the observation device casing is composed of an upper light shielding plate 7 with a round hole in the center, an annular transparent glass protective cover 8, a light shielding bottom plate 9, a hemispherical transparent glass protective cover 10 and an annular rain shielding plate 15. The light shielding bottom plate 9 is disc-shaped, provides an assembly table for other parts, shields ambient stray light below the instrument, and is provided with a screw thread adapter 14 serving as a mounting bracket for fixing at the center below the light shielding bottom plate 9; the annular transparent glass protective cover 8 surrounds the edge of the shading base plate 9 and is fixed above the shading base plate 9, so that ambient light can penetrate through and enter the lens 2; the upper light shielding plate 7 is arranged above the transparent glass protective cover 8, and a round hole is formed in the center of the upper light shielding plate so that the fisheye wide-angle lens 4 is completely exposed, and meanwhile, the environment stray light above the industrial CCD camera is shielded; the hemispherical transparent glass protection cover 10 is arranged above the central round hole of the upper light shielding plate 7 to protect the fisheye wide-angle lens; the annular rain shield 15 is installed around the edge below the light shielding bottom plate 9 to prevent rainwater, sundries, and the like from affecting the normal operation of the high-sensitivity sound receiver 6 and the heat radiation fan 15. Two identical heat dissipation fans 13 are symmetrically installed at the back of the light shielding bottom plate 9.
The optical module of the observation device consists of 8 identical transmission gratings, 8 identical industrial CCD cameras and a full-sky imager. The transmission gratings 1 are arranged on the shading bottom plate 9 through grating supports 11 and are arranged close to the front end of the lens 2, and 8 transmission gratings 1 and the grating supports 11 thereof are identical; each industrial CCD camera consists of a lens 2 and an industrial CCD camera body 3, and is arranged on a shading bottom plate 9 through a fixed bracket 12, 8 industrial CCD cameras are arrayed in a ring shape at a mutual interval of 45 degrees, and the field of view of each industrial CCD camera is 95 degrees; the all-sky imager consists of a fisheye wide-angle lens 4 and a corresponding all-sky imaging CCD camera body 5, and is arranged at the right center above a shading bottom plate 9 through a fixed bracket 12.
The acoustic module of the observation device consists of two identical high-sensitivity acoustic receivers 6. The two high-sensitivity sound receivers 6 are symmetrically mounted under the light-shielding bottom plate 9 by a fixing bracket 12.
The data processing equipment comprises a data acquisition module, a storage module, a control module and a data processing module. The data storage module can acquire data by using equipment such as a high-speed acquisition card and the like and store the data in a high-speed solid state disk in a classified mode, the control module can automatically control observation equipment such as a computer or a singlechip and the like, and the data processing module can process the data in real time to acquire information such as lightning positioning, fine spectrum, various physical parameters of a lightning channel and the like.
The working principle of the full-field visible light-near infrared spectrum detector provided by the invention is described below.
The basic operation and procedure of the present invention is shown in fig. 4. When lightning occurs near the instrument, the luminescence phenomenon generated by the lightning channel can be captured by the observation equipment. The visible light and near infrared light emitted by lightning enter the lens 2 after diffraction and light splitting action of the transmission grating 1 and are imaged on a CCD chip in the industrial CCD camera body 3, so that spectral image information of a lightning channel can be recorded by the CCD and temporarily stored in a memory of the camera; at the same time, the visible light emitted by lightning is also recorded by the all-sky imager. In this way, image information such as the angular position of the lightning channel light spot and the time of arrival of the light are temporarily cached in the observation device. In addition, the thunder signal caused by the lightning channel is received by the high-sensitivity sound receiver 6 in the acoustic module, the thunder sound wave signal is identified from the environment through the characteristics such as frequency, and the arrival time of the thunder sound signal is recorded. The whole observation equipment is started up and then continuously records, and various acquired information is temporarily cached in a memory of the machine body no matter whether lightning occurs around, the caching period is 2s, but all data information is not recorded in the storage module at the moment. Because the full-view field visible light near infrared spectrum detector provided by the invention judges and records the lightning event in a triggering mode, namely, whether the actual lightning event occurs is judged by the external lightning positioning instrument, when the lightning event does occur in the view field, the external lightning positioning instrument can send a triggering signal to the control module, then, data temporarily cached in the memory of the observation equipment body can be sent to the data acquisition and storage module, and then, the data are sent to the data processing module for inversion calculation. The transmitted data are information collected within 1s (2 s in total) before and after the trigger point. The data processing module acquires 360-degree full-view pictures by performing image stitching on pictures shot by 8 identical industrial CCD cameras; inverting the spectrum information obtained by shooting, and calculating various physical parameters of an observed lightning channel; at the same time, the location of nearby lightning channels can be calculated by means of the time difference between the arrival of the acoustic signal and the optical signal at the detector. Thus, a complete observation of a lightning event is completed.
Specifically, the principle of acquiring spectrum information by the full-view visible near infrared lightning spectrum detector, the full-view splicing process, the method for positioning lightning by using acousto-optic difference and the calculation of various physical parameters of a lightning channel are as follows;
(1) Principle of acquiring spectral information:
as shown in fig. 5, the principle of spectrum shooting in the full-field visible near infrared lightning spectrum detector provided by the invention is shown. Since the distance between the lightning channel and the instrument is far greater than the size of the transmission grating, it can be considered that light rays at a point on the lightning channel propagate to the grating like parallel light. The optical axes of the transmission grating, the lens and the CCD are drawn with horizontal dashed lines. Parallel light emitted by a certain point on the lightning channel enters the grating at an angle theta with the optical axis, and light with different wavelengths can be emitted in different diffraction angles through diffraction of the grating. For convenience of explanation, assume that the wavelength of incident light is λ, the diffraction angle is ψ in fig. 4, and the diffracted parallel light is converged at point a on the CCD in the industrial-scale CCD camera body 3 through the lens in the lens 2 of the industrial-scale CCD camera. Parallel light with different wavelengths emitted by the lightning channel is diffracted by the grating and converged by the lens and then appears at different positions of the CCD, so that a spectrum image is formed. Recorded on the CCD are the 0 order primary image and the + -1 order spectrum.
Wherein the time resolution parameter of the optical module is closely related to the performance of the CCD used. The time resolution of the industrial CCD camera used by the invention is generally 50 frames/second to 200 frames/second, and the CCD camera with more excellent use performance can achieve higher time resolution.
The spectral wavelength angular resolution of the industrial-grade CCD camera can be calculated according to the diffraction characteristics of the grating. According to the grating equation, there are:
a[sinψ-sinθ]＝mλ (1)
(1) Where a is a grating constant, i.e. the distance between two adjacent lines on the grating, m is the number of stages of the grating, ψ is the diffraction angle, θ is the angle of incidence, and λ is the wavelength of the light. Both ψ and θ are positive when the incident light and the diffracted light are on opposite sides of the grating normal, and ψ is negative when the incident light and the diffracted light are on the same side of the grating normal. Thus, the diffraction angle ψ expression of the first order spectrum can be obtained:
(2) In the formulas (3), the shorter the wavelength λ of the light, the smaller the diffraction angle ψ, and hence the closer the spectrum is to the bluish-violet light, the denser the distribution of the light rays of different wavelengths, and the worse the resolution. For visual illustration, the parameter a (average wavelength change per degree) is used herein to characterize the angular resolution, the greater the range of wavelength changes contained per 1 degree angle, the poorer its angular resolution. The calculation formula of the parameter A is as follows:
according to equation (4), for example, assuming that a beam of visible parallel light (wavelength range 390-780 nm) is incident on a transmission grating with a number of lines of 800 lines/mm at an angle of sin θ=0.2, the value of the parameter a of the primary spectrum received on the CCD is approximately 15.796nm/degree. At this time, the A value of the red light part of the primary spectrum is smaller than 15.796nm/degree, and the angular resolution is better; in the violet part of the primary spectrum, the A value is greater than 15.796nm/degree, where the angular resolution is poor. Higher grating numbers can achieve better spectral angular resolution.
(2) And (3) a panoramic image stitching process:
specifically, as shown in fig. 6, a method for splicing full-field images of the full-field visible light near-infrared lightning spectrum detector is shown. Fig. 6 (a) shows the acquisition of a 360 ° field of view, using this method to ensure the integrity of the imaging of the spectrum on the CCD; fig. 6 (b) shows the field of view of a single industrial grade CCD camera. The fields of view of each industrial grade CCD camera are 95 deg., overlap each other, and the shading in the figure indicates overlapping adjacency at the edges of the fields of view of the cameras. Specifically, two adjacent fields of view overlap by 27.5 ° between (1) and (2); two fields of view, e.g., (1) and (3), which are 1 field of view apart in the middle overlap by 5 °. The 8 identical fields of view are arranged in sequence in the manner described above. After each industrial CCD camera shoots an image, conventional image stitching is performed on 8 images, and finally a full-view spectrum image is obtained. Fig. 7 shows the independent fields of view of an industrial grade CCD camera and the panoramic field of view stitched from the independent fields of view. 8 industrial CCD cameras with identical structures record independent visual fields at different positions respectively, and then in a control processing module, the independent visual fields are finally synthesized into panoramic images with 360-degree visual fields through a conventional image stitching technology.
(3) The method for positioning lightning by using all-sky images and acousto-optic differences comprises the following steps:
specifically, fig. 8 shows a schematic diagram of lightning positioning by using the full-field visible near infrared lightning spectrum detector provided by the invention through the arrival time difference of the acoustic and optical signals. N is the north direction, E is the east direction, O is the center of the field of view, P is a spot taken in the field of view, and P has an azimuth of γ. FIG. 7 is a schematic representation of an image taken by an all-sky imager, with the light rays on objects far from the camera being strongly distorted through the fisheye lens, so that the recorded image is approximately circular; fig. 8 (b) shows the corrected distorted field of view, P, with the azimuth angle unchanged and P being a distance L from the center of the field of view (i.e., the instrument center). Fig. 9 shows an image obtained by direct photographing by the all-sky lightning positioner and an image after distortion correction. The distance L can be obtained by the following equation:
L＝v×(t 1 -t 2 ) (5)
where v is the speed of sound, typically 340m/s; t is t 1 Bit thunder signal arrival time, t 2 Time of arrival for the optical signal.
The lightning channel is positioned by using an acousto-optic arrival time difference method, and the detection distance is mainly influenced by the propagation characteristics of the acoustic signals. Assuming that a point of a lightning channel where thunder is generated is regarded as a point sound source, in an ideal case, the thunder is attenuated in a spherical wave form in the propagation, and the following formula is adopted:
(6) Where Δl is the attenuation degree of sound during propagation, in dB, r is the distance of sound propagating from the point source to a certain point, in m.
For example, considering an ideal case, assuming that a thunder has 145dB at a point sound source, a high-sensitivity sound receiver can detect a thunder of 50dB at the minimum, and the energy of the thunder propagates in a spherical wave form in free space, the limit distance of the thunder that the high-sensitivity sound receiver can receive is about 15km according to the above equation. However, in reality, under the influence of factors such as complex environment and noise around the instrument, the detection range of the actual thunder may be far smaller than the limit value, and the detection range of the thunder may be different from case to case. In general, the acousto-optic difference positioning method provided by the invention is suitable for the condition that a lightning channel is close to an instrument, and when the lightning channel is far from the instrument, the acoustic signal information is lost, and at the moment, the optical signal information is mainly analyzed and processed.
(4) The positioning method of each physical parameter of the lightning channel comprises the following steps:
FIG. 10 shows a schematic representation of the spectral lines of a lightning channel obtained according to the invention. By combining the acquired spectrum information, important basic physical parameters such as temperature, electron concentration, conductivity and the like of the lightning channel can be inverted.
a. Channel temperature:
the lightning channel temperature may be calculated by a two-spectral or multi-spectral method. The channel temperature is one of the most basic parameters, and as long as the channel temperature T is calculated, other physical parameters of the channel can be further calculated.
The two-spectral line method is used for calculating the intensity ratio of two spectral lines of the same element:
(7) Wherein k is a Boltzmann constant; lambda is the wavelength; e (E) 1 、E 2 To exciteThe energy unit is eV, and is obtained by spectral line detection; g is statistical weight, A is transition probability, and the value of the transition probability can be also checked by a nist database; i 1 、I 2 Is the line intensity, which can be measured by spectrum. The plasma temperature can thus be calculated. When the temperature is calculated by the two-spectral line method, the excitation energy of the two selected spectral lines is greatly different. As shown in fig. 10, the channel temperature T may be calculated taking into account the above equation taking into account the relevant parameter bands for the NI 648.2 and NI 821.6 spectral lines.
In the LTE (local thermodynamic equilibrium) model, the multispectral method is calculated from multiple spectral lines of the same element:
(8) Wherein I is the relative intensity of spectral line, lambda is wavelength, g is statistical weight, A is transition probability, E is excitation energy. The temperature T can be obtained from the slope of a straight line by fitting the straight line by a least square method using E as the abscissa and ln (In/gA) as the ordinate. When more clear spectral lines are obtained, a more accurate channel temperature inversion value can be obtained by using a multi-spectral line method. As shown in fig. 10, the calculation may be considered to select the line of the NII.
b. Electron density
Under the LTE approximation, the calculation is carried out by a Saha equation:
(9) Wherein n is e Is electron number density, I a 、I i The intensity of the atomic line and the ion line of the same element, V is ionization energy of atoms, and T is channel temperature. Electron density n e Based on the solution of the channel temperature T, the electron density n can be easily solved after the channel temperature T is calculated by a two-spectral line method or a multi-spectral line method e Is a value of (2).
c. Channel conductivity
Considering the lightning channel as consisting of plasma, the conductivity can be calculated by:
(10) Where σ is channel conductivity, n e The electron number density, T is the channel temperature. Sequentially solving the channel temperature T and the electron density n e After that, the channel conductivity σ can also be easily obtained.
In summary, the invention overlaps the visual fields of eight annular evenly-installed industrial CCD cameras, can provide panoramic images when lightning occurs, and can finally obtain full visual field optical images when lightning event occurs by matching with a full sky imager.
The above-described embodiments serve to describe the substance of the present invention in detail, but those skilled in the art should understand that the scope of the present invention should not be limited to this specific embodiment.
Claims (5)
1. The utility model provides a full visual field visible light near-infrared lightning spectrum detection appearance, includes observation equipment and data processing equipment, its characterized in that: the observation equipment comprises an instrument shell, an optical module and an acoustic module;
the instrument shell comprises an upper light shielding plate, an annular transparent glass protecting cover, a light shielding bottom plate, a hemispherical transparent glass protecting cover and an annular rain shielding plate, wherein a round hole is formed in the center of the upper light shielding plate; the shading bottom plate is disc-shaped, and a bracket adapter used for fixing the mounting bracket is arranged in the center below the shading bottom plate; the annular transparent glass protective cover surrounds the edge of the shading bottom plate and is fixed above the shading bottom plate; the upper light shielding plate is arranged above the transparent glass protective cover, and a round hole is formed in the center of the upper light shielding plate so that the fisheye wide-angle lens is completely exposed; a hemispherical transparent glass protective cover for protecting the fisheye wide-angle lens is arranged above the central round hole of the upper light shielding plate; the annular rain shield surrounds the edge arranged below the shading bottom plate;
the optical module comprises eight identical transmission gratings, eight identical industrial CCD cameras and a full-sky imager; the transmission grating is arranged on the shading bottom plate through a grating bracket and is arranged close to the front end of the lens; each industrial CCD camera consists of a lens and an industrial CCD camera body, and is arranged on a shading bottom plate through a fixed bracket, and eight industrial CCD cameras are arranged in a ring shape at an interval of 45 degrees; the full-sky imager comprises a fish eye wide-angle lens and a corresponding full-sky imaging CCD camera body, and is arranged at the right center above the shading bottom plate through a fixed bracket; the acoustic module comprises a sound receiver which is arranged below the shading bottom plate through a fixed bracket;
a heat radiation fan is arranged on the back of the shading bottom plate;
the acoustic module comprises two identical high-sensitivity sound receivers which are symmetrically arranged below the shading bottom plate through a fixed bracket.
2. The full field of view visible near infrared lightning spectrum detector of claim 1, wherein: the two identical cooling fans are symmetrically arranged on the back surface of the shading bottom plate.
3. The full field of view visible near infrared lightning spectrum detector of claim 1, wherein: the field of view of each industrial grade CCD camera is 95 °.
4. The full field of view visible near infrared lightning spectrum detector of claim 1, wherein: the data processing equipment comprises a data acquisition module, a storage module, a control module and a data processing module.
5. The full field of view visible near infrared lightning spectrum detector of claim 4, wherein: the control module is a computer or a singlechip.
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| CN102520463A (en) * | 2011-11-01 | 2012-06-27 | 中国科学院大气物理研究所 | All-sky visible light cloud imaging system |
| CN103292902A (en) * | 2013-05-29 | 2013-09-11 | 南京信息工程大学 | Dayglow temperature photometer and method thereof for detecting airglow spectrum intensity and temperature |
| CN103472501A (en) * | 2013-09-06 | 2013-12-25 | 中国气象科学研究院 | Cloud and aerial total cloud amount detection method and system |
| CN205103423U (en) * | 2015-11-19 | 2016-03-23 | 中国民航大学 | Prevailing visibility automatic observer |
| CN207779555U (en) * | 2018-01-16 | 2018-08-28 | 南京信息工程大学 | A kind of full filed visible light near-infrared lightning spectrum detection instrument |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102520463A (en) * | 2011-11-01 | 2012-06-27 | 中国科学院大气物理研究所 | All-sky visible light cloud imaging system |
| CN103292902A (en) * | 2013-05-29 | 2013-09-11 | 南京信息工程大学 | Dayglow temperature photometer and method thereof for detecting airglow spectrum intensity and temperature |
| CN103472501A (en) * | 2013-09-06 | 2013-12-25 | 中国气象科学研究院 | Cloud and aerial total cloud amount detection method and system |
| CN205103423U (en) * | 2015-11-19 | 2016-03-23 | 中国民航大学 | Prevailing visibility automatic observer |
| CN207779555U (en) * | 2018-01-16 | 2018-08-28 | 南京信息工程大学 | A kind of full filed visible light near-infrared lightning spectrum detection instrument |
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