Accurate counting device for measuring concentration of ice nucleus

Abstract

The invention discloses an accurate counting device for measuring ice nucleus concentration, and relates to the field of ice crystal counting equipment, the accurate counting device comprises a glass channel, a laser emission unit, a laser beam concentration unit, a laser beam splitting unit and an external controller, the laser emission unit is installed on one side of the glass channel and used for irradiating polarized light to the glass channel, and the laser beam splitting unit is installed on the other side of the glass channel; the laser bundling unit is arranged around the glass channel and used for bundling polarized light reflected by air in the glass channel to the laser beam splitting unit, the laser beam splitting unit is used for splitting the received polarized light, and the external controller calculates the number of ice cores passing through the glass channel according to the polarized light after beam splitting. According to the invention, the P polarized light and the S polarized light are collected and processed, so that the ice crystal and the cloud droplet can be distinguished. The problem that an ice nucleus concentration measurement result is overestimated due to the fact that an existing non-polarized optical counter counts non-ice crystal (namely cloud droplet) particles without difference is effectively solved.

Description

Technical Field

[0001] The invention relates to the field of ice crystal counting equipment, and in particular to an accurate counting device for measuring ice nucleus concentration. Background Art

[0002] Currently, commercial ice nucleus concentration measurement instruments pass air samples through a cooling area, causing water vapor in the sample to condense on ice nuclei to form ice crystals, and use a counter to count the ice crystals passing through the cooling area in order to calculate the ice nucleus concentration. Existing counters will indiscriminately record all particles (cloud droplet particles, ice crystal particles, and aerosol particles) passing through the cooling area, resulting in an overestimation of ice crystal concentration measurements. Among them, the difficulty in improving the counter is how to make the counter accurately distinguish between ice crystals and cloud droplets with a particle size of less than 100 microns.

[0003] Therefore, how to provide an accurate counting device that can solve the problem of overestimation of ice crystal concentration measurement results has become a difficult problem that needs to be solved urgently by those skilled in the art. Summary of the invention

[0004] The purpose of the present invention is to provide an accurate counting device for measuring ice nucleus concentration, so as to solve the problem that the existing counters cannot effectively distinguish ice crystals and cloud droplets with a particle size less than 100 microns.

[0005] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0006] The present invention provides a precise counting device for measuring ice nucleus concentration, comprising a glass channel, a laser emitting unit, a laser beam focusing unit, a laser beam splitting unit and an external controller, wherein the glass channel is arranged at the output end of a cooling area in an ice crystal concentration measuring instrument; the laser emitting unit is installed on one side of the glass channel and is used to irradiate polarized light to the glass channel, the laser beam focusing unit is arranged around the glass channel and is located on the same side of the laser emitting unit and is used to focus the polarized light reflected by the air in the glass channel to the laser beam splitting unit, the laser beam splitting unit is used to split the received polarized light, and the external controller calculates the number of ice nuclei passing through the glass channel according to the split polarized light.

[0007] Optionally, the cross-section of the glass channel is cylindrical, and the laser emitting unit is arranged on the side wall of the glass channel.

[0008] Optionally, the laser emitting unit includes a laser, a half-wave plate and a right-angle prism, the right-angle prism is located around the glass channel, and the laser emitted by the laser is vertically incident on one right-angle surface of the right-angle prism after passing through the half-wave plate, and then emitted from the other right-angle surface of the right-angle prism and vertically incident on the glass channel.

[0009] Optionally, the laser beam focusing unit includes a convex lens, a light shielding sheet, and a collimating lens. The convex lens is located around the glass channel. The convex lens focuses the polarized light reflected by the air in the glass channel onto the collimating lens. The collimating lens turns the incident polarized light into a parallel light beam and shoots it towards the laser beam splitting unit. The light shielding sheet is attached to the collimating lens and is located between the convex lens and the collimating lens.

[0010] Optionally, the laser beam splitting unit includes a polarization beam splitter prism, a first photodetector, and a second photodetector. The polarization beam splitter prism is used to receive the parallel light beam emitted by the collimating lens and split the received parallel light beam into a parallel polarized light and a perpendicular polarized light. The first photodetector is used to receive the parallel polarized light, and the second photodetector is used to receive the perpendicular polarized light. The first photodetector and the second photodetector are used to convert the received optical signal into an electrical signal. Both the first photodetector and the second photodetector are electrically connected to the external controller.

[0011] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0012] Cloud droplets are spherical, and ice crystals are non-spherical or in the form of crystalline particles. Spherical particles mainly scatter P-polarized light (light in the same polarization plane as the incident light), and non-spherical or crystalline particles scatter less P-polarized light and more S-polarized light (light perpendicular to the polarization plane of the incident light). By collecting and processing P-polarized light and S-polarized light, the present invention can distinguish ice crystals from cloud droplets, and calculate the ice crystal concentration by counting the number of particles passing through the glass channel. It effectively solves the problem that the existing non-polarized optical counter overestimates the measurement result of the ice nucleus concentration due to the undifferentiated calculation of non-ice crystal (i.e., cloud droplet) particles. Description of the Drawings

[0013] The present invention will be further described below with reference to the drawings.

[0014] Figure 1 It is a schematic diagram of the principle of an accurate counting device for measuring ice nucleus concentration according to the present invention.

[0015] Description of the reference numerals: 1. Glass channel; 21. Laser; 22. Half-wave plate; 23. Right-angled triangular prism; 31. Convex lens; 32. Light shielding sheet; 33. Collimating lens; 41. Polarization beam splitter prism; 42. First photodetector; 43. Second photodetector. Detailed Embodiment

[0016] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clear and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0017] As Figure 1 shown, a precise counting device for measuring ice nucleus concentration includes a glass channel 1, a laser emitting unit, a laser beam collecting unit, a laser beam splitting unit and an external controller. The glass channel 1 is arranged at the output end of the cooling area in the ice crystal concentration measuring instrument. The laser emitting unit is installed on one side of the glass channel 1 and is used to irradiate polarized light on the glass channel 1. The laser beam collecting unit is arranged around the glass channel 1 and on the same side as the laser emitting unit, and is used to collect the polarized light reflected by the air in the glass channel 1 to the laser beam splitting unit. The laser beam splitting unit is used to split the received polarized light, and the external controller calculates the number of ice nuclei passing through the glass channel 1 according to the split polarized light.

[0018] In specific implementation, since the peak polarization ratio of ice particles is less than 0.65, the external controller counts the number of particles with a peak polarization ratio less than 0.65 passing through the glass channel 1 according to the split polarized light, and then the number of ice nuclei can be obtained. Dividing by the gas volume passing through the glass channel 1 can calculate the ice nucleus concentration.

[0019] Specifically, the cross-section of the glass channel 1 is cylindrical, and the laser emitting unit is arranged on the side peripheral wall of the glass channel 1.

[0020] Specifically, the laser emitting unit includes a laser 21, a half-wave plate 22 and a right-angled prism 23. The right-angled prism 23 is located around the glass channel 1. The laser emitted by the laser 21 is vertically incident on a right-angled surface of the right-angled prism 23 after passing through the half-wave plate 22, and then exits from another right-angled surface of the right-angled prism 23 and is vertically incident on the glass channel 1.

[0021] Specifically, the half-wave plate 22 is used to adjust the phase of the polarized light beam emitted by the laser 21.

[0022] Specifically, the laser beam collecting unit includes a convex lens 31, a light shielding sheet 32 and a collimating lens 33. The convex lens 31 is located around the glass channel 1. The convex lens 31 collects the polarized light reflected by the air in the glass channel 1 to the collimating lens 33. The collimating lens 33 turns the incident polarized light into a parallel light beam and shoots it to the laser beam splitting unit. The light shielding sheet 32 is attached to the collimating lens 33 and is located between the convex lens 31 and the collimating lens 33.

[0023] In specific implementation, the light-shielding sheet 32 is used to filter the reflected light located at the center of the collimating lens 33 reflected by the glass channel 1, so that the scattered polarized light passes through the collimating lens, thereby better collecting the required polarized light information.

[0024] Specifically, the laser beam splitting unit includes a polarization beam splitting prism 41, a first photodetector 42 and a second photodetector 43. The polarization beam splitting prism 41 is used to receive the parallel light beam emitted by the collimating lens 33 and split the received parallel light beam into a parallel polarized light and a perpendicular polarized light. The first photodetector 42 is used to receive the parallel polarized light, and the second photodetector 43 is used to receive the perpendicular polarized light. The first photodetector 42 and the second photodetector 43 are used to convert the received optical signal into an electrical signal, and both the first photodetector 42 and the second photodetector 43 are electrically connected to the external controller.

[0025] Specifically, a signal processor for amplifying and digitally processing the electrical signals transmitted by the first photodetector 42 and the second photodetector 43 is provided in the external controller.

[0026] The working principle of the present invention:

[0027] Cloud droplets are spherical, ice crystals are non-spherical or in the form of crystalline particles. Spherical particles mainly scatter P-polarized light (light in the same polarization plane as the incident light), and non-spherical or crystalline particles scatter less P-polarized light and more S-polarized light (light perpendicular to the polarization plane of the incident light). By collecting and processing P-polarized light and S-polarized light, the present invention can distinguish ice crystals from cloud droplets, and calculate the ice crystal concentration by counting the number of particles passing through the glass channel. It effectively solves the problem that the existing non-polarized optical counter overestimates the measurement result of the ice nucleus concentration due to the indiscriminate calculation of non-ice crystal (i.e., cloud droplet) particles.

[0028] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0029] The embodiments described above are only descriptions of the preferred embodiments of the present invention and do not limit the scope of the present invention. Without departing from the spirit of the present invention, various modifications and improvements made by those of ordinary skill in the art to the technical solutions of the present invention shall fall within the protection scope determined by the claims of the present invention.

Claims

1. An accurate counting device for measuring ice nucleus concentration, characterized in that: The invention comprises a glass channel (1), a laser emitting unit, a laser beam focusing unit, a laser beam splitting unit and an external controller, wherein the glass channel (1) is arranged at the output end of a cooling area in an ice crystal concentration measuring instrument; the laser emitting unit is installed on one side of the glass channel (1) and is used to irradiate polarized light to the glass channel (1); the laser beam focusing unit is arranged around the glass channel (1) and is located on the same side as the laser emitting unit and is used to focus the polarized light reflected by the air in the glass channel (1) to the laser beam splitting unit; the laser beam splitting unit is used to split the received polarized light; and the external controller calculates the number of ice nuclei passing through the glass channel (1) based on the split polarized light.

2. The precise counting device for measuring ice nucleus concentration according to claim 1, characterized in that: The cross section of the glass channel (1) is cylindrical, and the laser emitting unit is arranged on the side peripheral wall of the glass channel (1).

3. The precise counting device for measuring ice nucleus concentration according to claim 2, characterized in that: The laser emitting unit comprises a laser (21), a half-wave plate (22) and a right-angle prism (23); the right-angle prism (23) is located around the glass channel (1); the laser light emitted by the laser (21) passes through the half-wave plate (22) and is vertically incident on a right-angle surface of the right-angle prism (23), and then is emitted from another right-angle surface of the right-angle prism (23) and is vertically incident on the glass channel (1).

4. The accurate counting device for measuring ice nucleus concentration according to claim 2, characterized in that: The laser beam focusing unit comprises a convex lens (31), a light shielding sheet (32) and a collimating lens (33); the convex lens (31) is located around the glass channel (1); the convex lens (31) focuses polarized light reflected by air in the glass channel (1) onto the collimating lens (33); the collimating lens (33) converts the incident polarized light into a parallel light beam and emits it to the laser beam splitting unit; the light shielding sheet (32) is attached to the collimating lens (33) and is located between the convex lens (31) and the collimating lens (33).

5. The accurate counting device for measuring ice nucleus concentration according to claim 4, characterized in that: The laser beam splitting unit comprises a polarization beam splitting prism (41), a first photodetector (42) and a second photodetector (43); the polarization beam splitting prism (41) is used to receive a parallel light beam emitted by the collimating lens (33), and split the received parallel light beam into parallel polarized light and vertical polarized light; the first photodetector (42) is used to receive the parallel polarized light; the second photodetector (43) is used to receive the vertical polarized light; the first photodetector (42) and the second photodetector (43) are used to convert the received optical signal into an electrical signal; and the first photodetector (42) and the second photodetector (43) are both electrically connected to the external controller.

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