CN210665931U

CN210665931U - Ultraviolet imager

Info

Publication number: CN210665931U
Application number: CN201920993053.6U
Authority: CN
Inventors: 张幼文
Original assignee: Hangzhou Hetaike Technology Co ltd
Current assignee: Ningbo Qianshi Information Technology Co ltd
Priority date: 2019-06-28
Filing date: 2019-06-28
Publication date: 2020-06-02
Anticipated expiration: 2029-06-28

Abstract

The utility model relates to an optical imaging technical field discloses an ultraviolet corona imager, and wherein, one kind is single channel ultraviolet imager, and another kind is binary channels ultraviolet imager. The single-channel ultraviolet imager utilizes an ultraviolet illuminating lamp to illuminate the background, and utilizes a solar blind optical filter to obtain a background image, such as high-voltage equipment, and the illuminating lamp is automatically turned off when corona exists; in the absence of illumination, the solar blind filter images only the ultraviolet light emitted by the target, such as corona from defects; because the two images are in the same channel, the two images can be strictly overlapped point to point through the circuit board no matter the distance is far or near, and no matter day or night, and the exact position of the defect can be known; the ultraviolet imager with two channels and the wide-spectrum objective shared by ultraviolet light and visible light has small volume, large visual field and no parallax, and can ensure that a corona image and a background image are completely same after passing through the image fusion plate, thereby being capable of respectively observing and dynamically aligning and realizing the detection and positioning of ultraviolet corona.

Description

Ultraviolet imager

Technical Field

The utility model relates to an optical imaging technical field has especially related to an ultraviolet imager.

Background

The ultraviolet imager can be used to display the fused image of the corona and insulation equipment, locate the corona and see the defects. As shown in fig. 1, most of the existing uv imagers use a beam splitter or a mirror in incident light, and then use two objective lenses to image a uv target onto a uv ICCD and a visible background onto a common CCD, and these uv imagers mainly have the following problems:

(1) the beam splitter or the reflecting mirror is not small in size, and the system is larger in size by using two objective lenses;

(2) two different objective lenses and detectors do not look at the same target, so that the parallax, the field of view size and the magnification are different, point-to-point superposition is achieved at a certain distance by image processing, and the image is not aligned as the distance is changed, so that dynamic measurement cannot be performed;

(3) because the focal lengths are different, the ultraviolet and visible light channels cannot focus and measure distance by using the sharpness of the image at the same time;

(4) the corona is bright, the defects in the background are covered, and the position cannot be determined; at night, no light exists, and the background cannot be shot for fusion;

(5) the existing ultraviolet imaging instrument has large volume, high price and variable measurement.

At present, the Chinese patent with application number 200810046823.2 discloses a test method for detecting corona of an ultra-high voltage transmission line based on an ultraviolet imaging technology, which adopts an ultraviolet imager working at a wave band of 240-280 nm and shooting 20 meters away from a measured object, and can effectively detect the corona of a sample.

SUMMERY OF THE UTILITY MODEL

The utility model discloses to the above-mentioned shortcoming that exists among the prior art, provide new ultraviolet imager, the utility model discloses an ultraviolet imager includes two kinds, and one kind is single channel ultraviolet imager, and another kind is binary channels ultraviolet imager.

In order to solve the technical problem, the utility model discloses a following technical scheme solves above-mentioned shortcoming: an ultraviolet imager can be a single-channel ultraviolet imager and comprises an ultraviolet illuminating lamp, an objective lens, a solar blind optical filter, a detector and a circuit board, wherein the ultraviolet illuminating lamp is arranged on one side of the objective lens and used for providing a light source to irradiate a target, ultraviolet light and visible light reflected by the target enter the objective lens, and the ultraviolet illuminating lamp is an LED lamp with the wavelength of 232-270 nm; the solar blind optical filter is arranged on one side, away from the ultraviolet illuminating lamp, of the objective lens and used for filtering visible light entering the objective lens, the detector is arranged behind the solar blind optical filter and used for imaging corona ultraviolet light in the absence of illumination and background ultraviolet light in the presence of illumination, the circuit board is connected with the detector and used for converting the background into a background image and converting the corona into a corona image, and the background image and the corona image are superposed or fused.

Preferably, the ultraviolet illuminating lamp is an LED lamp which is manufactured by adopting a GaN (gallium nitride) and AlN (aluminum nitride) single-layer film of an atomic scale control interface and has a dead zone of 232-270 nm in day. The utility model discloses with the blind light filter of day that only can see through the ultraviolet ray that the wavelength is 240 ~ 280nm and filter sunshine completely, only survey the ultraviolet ray of corona. However, the background without sunlight can not be seen, so that the LED lamp of the utility model can be used for lighting to obtain an ultraviolet background image through the solar blind filter, and the background can be imaged no matter in the day or at night.

Once the corona is found, the LED lamp is automatically turned off, and does not interfere with the corona. Therefore, the utility model discloses a corona image that ultraviolet imager generated and two image proportions of background image are the same big, and automatic point-to-point aims at, make this ultraviolet imager smaller and more exquisite, low-priced and practical.

Preferably, the ultraviolet lens has a transmission peak in a solar dead zone of 0.24 to 0.28 μm.

Preferably, the detector comprises a refrigerated back illuminated sCMOS or an ultraviolet ICCD.

The first single channel uv imager provided images both the background (e.g., cables and high voltage devices) and the target (i.e., corona due to defects) through the same objective lens, the same solar blind filter, and on the same detector, with the same field of view and magnification of the image. Therefore, a complex image fusion plate is not needed, the strict point-to-point automatic fusion can be realized only by using a single circuit board, and the device has the advantages of small volume, high precision, firmness, reliability, water resistance, durability and low price.

An ultraviolet imager, which can also be a dual-channel ultraviolet imager, comprises an objective lens, a beam splitter, a solar blind optical filter, a visible light optical filter, a first detector, a second detector, an image fusion plate and a display screen; the objective lens is a wide spectrum objective lens which can transmit light with the wavelength of 220-780 nm; the beam splitter is arranged behind the objective lens and is used for reflecting ultraviolet light and transmitting visible light; the solar blind optical filter is arranged on the reflecting surface of the beam splitter and used for filtering visible light and transmitting ultraviolet light, and the solar blind optical filter only transmits the ultraviolet light with the wavelength of 240-280 nm; the first detector is arranged behind the solar blind filter and used for imaging by corona ultraviolet light; the visible light filter is arranged on the transmission surface of the beam splitter and is used for filtering ultraviolet light and transmitting visible light; the second detector is arranged behind the visible light filter and is used for visible light imaging; the image fusion plate is connected with the first detector and the second detector respectively and used for processing and fusing the images to obtain point-to-point fusion images; the display screen is connected with the image fusion board and used for displaying the fusion image.

Preferably, the solar blind filter only transmits ultraviolet light with the wavelength of 240-280 nm, the in-band transmittance of the solar blind filter is 18-22%, and the out-of-band cut-off depth is OD (optical sensitivity) 11-13.

Preferably, the first detector and the second detector comprise sCMOS, refrigerated back illuminated sCMOS or uv ICCD, the refrigerated back illuminated sCMOS of the first detector being a refrigerated back illuminated high resolution uv enhanced sCMOS, wherein the high resolution is, for example, 2048 x 2018 picture elements. The quantum efficiency of sCMOS is 78% averagely in the day blind zone of 240-280 nm and 80% averagely in the visible zone of 380-780 nm, which is better than that of ultraviolet non-response EMCCD (electron multiplication CCD) and common back-illuminated CMOS, and the optical sensitivity reaches 5 x 10^-5Lux, which can be used in both the ultraviolet and visible channels, works well with a broad spectrum objective.

Ultraviolet sensitivity due to refrigeration backlighting sCMOSSpecific ultraviolet ICCD 10^-6The Lux is slightly lower, and a photomultiplier tube can be connected in front of the refrigeration back illumination sCMOS for single photon detection if necessary, so that the ultraviolet sensitivity of the refrigeration back illumination sCMOS is higher than that of the ultraviolet ICCD.

Preferably, the objective lens has an average transmittance of 90-95% for light with a wavelength of 240-280 nm and an average transmittance of 70-75% for light with a wavelength of 380-780 nm, can automatically focus and range according to image sharpness, can image ultraviolet and visible light channels simultaneously, and is easy for point-to-point real-time fusion.

Preferably, the visible light filter can transmit light with a wavelength of 380-780 nm, and the transmittance is 94-96%.

Preferably, the image fusion plate scales the image and performs point-to-point fusion of the target and background images to determine the location of the corona on the background.

The two-channel ultraviolet imager is not provided with a lighting lamp, the two channels share a wide-spectrum objective lens, and ultraviolet light and visible light are divided into two equivalent paths through a 350nm beam splitter after entering the same objective lens to form a visible light channel and an ultraviolet light channel. In an ultraviolet light channel, ultraviolet light passes through a solar blind filter to form corona images on a refrigeration back lighting sCMOS; in the visible light channel, visible light images the background on the high-sensitivity sCMOS through the visible light filter, and the visible light can also image on the common back-illuminated CMOS due to the strong visible light. The two images are processed by the image fusion plate, point-to-point superposed and fused in real time, the number, the shape and the intensity of the light pulse are measured and compared with the known calibration body, the environmental influence is eliminated, the intensity of the light pulse is measured, the corona current intensity is calculated, and quantitative measurement is carried out to estimate the severity of the defect.

Because the ultraviolet and visible light channels share one objective lens, no parallax exists, the visual fields are the same, the optical distances are the same, the detectors are also the same, therefore, no matter whether the target is far or near or whether the instrument moves, the two images can be strictly aligned, the superposition precision of the ultraviolet and visible light images can be less than 0.1mrd, and the corona is accurately positioned in the background. The see-through corona and the night background imaging can be illuminated with a 532nm laser.

Furthermore, the utility model discloses an ultraviolet imager can also link up with electric wire netting, high-speed railway, army and build the database, makes correct defect identification with degree of depth study and artificial intelligence.

The utility model discloses owing to adopted above technical scheme, have apparent technological effect:

the utility model discloses a single channel ultraviolet imager utilizes the ultraviolet light to throw light on to the background for the first time, can obtain the background image to its point-to-point stack on corona image, with corona accurate positioning, the system is very simple.

The utility model discloses a binary channels ultraviolet imager uses the sharing objective of passing through ultraviolet light and visible light simultaneously for the first time, and the parallax is eliminated to the same visual field, makes two images of corona image and background image equally big, can realize automatic point-to-point alignment, can realize the detection and the location to ultraviolet corona.

Compare with the ultraviolet imager who uses beam splitter and two objective at present, the utility model discloses an ultraviolet imager performance is more superior, and the precision is higher, and the volume is littleer, and the price is cheaper.

The utility model discloses an ultraviolet imager can reach ultraviolet sensitivity<1×10^-18W/cm²Sensitivity to corona

The image processing method has the technical effects of <1PC @10m, image superposition accuracy <0.1mrd, a focusing range of 1m to infinity, mean time to failure >1 ten thousand hours and a technical readiness >8 level, and also has the functions of automatic focusing and ranging according to image sharpness. Which cannot be achieved with two objectives.

Drawings

Fig. 1 is a schematic structural diagram of a conventional ultraviolet imager.

FIG. 2 is a schematic structural view of embodiment 1. FIG. 3 is a schematic structural view of embodiment 2.

Fig. 4 is a graph of the spectral transmittance of the objective lens.

Fig. 5 is a graph of the spectral transmittance of a solar-blind filter.

Fig. 6 is a graph of the spectral responsivity of a cooling backlight sCMOS.

Fig. 7 is a diagram of corona detection in a high voltage power system according to example 1-2, wherein (a) is a visible background diagram, (b) is a fused image diagram, and (c) is an ultraviolet corona diagram.

The names of the parts indicated by the numerical references in the drawings are as follows: the device comprises an objective lens 1, a solar blind filter 2, a detector 3, an ultraviolet illuminating lamp 4, a beam splitter 5, a visible light filter 6, an image fusion plate 7, a display screen 8, a background 9, a corona 10, a first detector 11, a second detector 12, a reflector 13, a background image 14, a corona image 15 and a circuit board 16.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples.

Example 1

The single-channel ultraviolet imager is shown in fig. 2 and comprises an ultraviolet illuminating lamp 4, an objective lens 1, a solar blind optical filter 2 and a detector 3, wherein the ultraviolet illuminating lamp 4 is arranged on one side in front of the objective lens 1 and used for providing a light source to irradiate a target and a background, ultraviolet light and visible light reflected by the target enter the objective lens 1, and the ultraviolet illuminating lamp 4 is an LED lamp with the wavelength of 232-270 nm; the solar blind filter 2 is arranged on one side of the back of the objective lens 1, which is far away from the ultraviolet illuminating lamp, and is used for filtering visible light entering the objective lens 1, the detector 3 is arranged on the back of the solar blind filter 2 and is used for imaging corona 10 ultraviolet light in the absence of illumination and background 9 ultraviolet light in the presence of illumination, the circuit board 16 is connected with the detector 3 and is used for converting the background 9 into a background image 14 and converting the corona 10 into a corona image 15, and the background image 14 and the corona image 15 are superposed or fused, so that the background image 14 and the corona image 15 are imaged on the same detector 3 in the same proportion.

The solar blind filter 2 only transmits ultraviolet light with the wavelength of 240-280 nm, the average transmittance in a band of the solar blind filter 2 is 18%, and the out-of-band cut-off depth is OD 12.

The objective lens 1 is an ultraviolet lens with a transmission peak value in a day blind zone of 0.24-0.28 mu m.

The ultraviolet illuminating lamp 4 is an LED lamp which is manufactured by adopting a GaN and AlN single-layer film of an atomic-level control interface and has a day blind area with the wavelength of 232-270 nm.

The detector 3 is an ultraviolet ICCD.

The background 9 can be imaged by the solar blind filter 2 by using the ultraviolet illuminating lamp 4 for illumination, and a background image 14 is obtained; ultraviolet light of the corona 10 enters an objective lens 1, passes through ultraviolet light with the wavelength of 240-280 nm through a solar blind filter 2, and then images the corona 10 on a detector 3 to obtain a corona image 15. Once the corona 10 is found, the ultraviolet illuminating lamp 4 is automatically turned off, and the corona 10 is not interfered.

The first single-channel ultraviolet imager provided images the background (e.g., cables and high voltage equipment) and the target (corona due to defects) on the same detector through the same objective lens and the same solar blind filter, with the field of view and image magnification being identical. Therefore, the point-to-point fusion can be strictly realized without an image fusion plate, and the device has the advantages of small volume, high precision, firmness, reliability, water resistance, durability and low price.

Example 2

The dual-channel ultraviolet imager is shown in fig. 3 and comprises an objective lens 1, a beam splitter 5, a solar blind filter 2, a visible light filter 6, a first detector 11, a second detector 12, an image fusion plate 7 and a display screen 8; the beam splitter 5 is arranged behind the objective lens 1 and used for transmitting ultraviolet light and visible light; the solar blind filter 2 is arranged on the reflecting surface of the beam splitter 5 and is used for filtering visible light and transmitting ultraviolet light; the first detector 11 is arranged behind the solar blind filter 2 and used for imaging by corona ultraviolet light; the visible light filter 6 is arranged on the transmission surface of the beam splitter 5 and is used for filtering ultraviolet light and transmitting visible light; the second detector 12 is arranged behind the visible light filter 6 and used for visible light imaging; the image fusion plate 7 is connected with the first detector 11, the image fusion plate 7 is connected with the second detector 12, and the image fusion plate 7 is used for processing and fusing images to obtain point-to-point fusion images; the display screen 8 is connected with the image fusion plate 7, and the display screen 8 is used for displaying the fusion image.

As can be seen from FIG. 4, the objective lens 1 is a broad spectrum objective lens which can transmit light with a wavelength of 220-780 nm, the average transmittance of the objective lens 1 to light with a wavelength of 240-280 nm is 94-96%, the average transmittance of the objective lens 1 to light with a wavelength of 380-780 nm is 70-75%, the objective lens 1 can automatically focus and measure distance according to image sharpness, images ultraviolet and visible light channels simultaneously, and is easy for point-to-point real-time fusion.

As can be seen from fig. 5, the solar-blind filter 2 only transmits ultraviolet light with a wavelength of 240 to 280nm, the in-band average transmittance of the solar-blind filter 2 is 18%, and the out-of-band cut-off depth is OD 12.

The first detector 11 is a refrigeration backlighting sCMOS, specifically a refrigeration backlighting high-resolution ultraviolet enhancement sCMOS, where the high resolution is 2048 × 2018 pixels. As can be seen from FIG. 6, the quantum efficiency of the refrigeration back-illuminated sCMOS is 78% on average in the day blind zone of 240-280 nm and 80% on average in the visible zone of 380-780 nm, which is better than that of the ultraviolet non-responsive EMCCD (electron multiplying CCD) and the common back-illuminated CMOS, and the optical sensitivity reaches 5 × 10^-5Lux, which can be used in both the ultraviolet and visible channels, works well with a broad spectrum objective.

The ultraviolet sensitivity of the refrigeration back illumination sCMOS is 10 of that of the ultraviolet ICCD^-6The Lux is slightly lower, and a photomultiplier tube can be connected in front of the refrigeration back illumination sCMOS for single photon detection if necessary, so that the ultraviolet sensitivity of the refrigeration back illumination sCMOS is higher than that of the ultraviolet ICCD.

The second detector 12 is a sCMOS, or when the visible light is strong, the second detector 12 is a normal back-illuminated CMOS, and the size of the second detector 12 is the same as that of the first detector 11.

The visible light filter 6 can transmit light with a wavelength of 380-780 nm, and has a transmittance of 95%.

The image fusion plate 7 performs scaling on the image and performs point-to-point fusion on the target and background images to determine the location of the corona on the background.

Because two channels share one objective lens, the size is small, the visual field is as large, no parallax exists, two channels of images can be fused in real time by simply zooming regardless of distance and distance point-to-point, and the problem that the existing double-objective lens system cannot align distance and fuse in real time is solved.

Example 3

The ultraviolet imager of example 2 was used for corona detection in a high voltage power system, and the results are shown in fig. 4, in which (a) is a visible background image, (b) is a fused image, and (c) is an ultraviolet corona image.

As can be seen from fig. 7, the ultraviolet imager obtained in example 2 can not only clearly see the defects behind the corona, but also make the background image-forming without interfering with the corona, and the background and the corona can be processed and displayed respectively, thereby realizing the point-to-point fusion of the background image and the corona image and realizing the detection and positioning of the ultraviolet signal corona.

The ultraviolet imaging devices of examples 1 and 2 can achieve ultraviolet sensitivity<1×10^-18W/cm²Sensitivity to corona<1PC @10m, image overlay accuracy<0.1mrd, focusing range 1m ~ infinity, mean time to failure>1 ten thousand hours, degree of technical readiness>The technical effect of 8 levels, and the functions of automatic focusing and distance measurement according to the image sharpness.

In short, the above description is only a preferred embodiment of the present invention, and all the equivalent changes and modifications made in accordance with the claims of the present invention should be covered by the scope of the present invention.

Claims

1. An ultraviolet imager, comprising: the device comprises an ultraviolet illuminating lamp (4), an objective lens (1), a solar blind optical filter (2), a detector (3) and a circuit board (16); the ultraviolet illuminating lamp (4) is arranged on one side of the objective lens (1) and used for providing a light source to irradiate a target, ultraviolet light and visible light reflected by the target enter the objective lens (1), and the ultraviolet illuminating lamp (4) is an LED lamp with the wavelength of 232-270 nm; the solar blind optical filter (2) is arranged on one side of the objective lens (1) departing from the ultraviolet illuminating lamp and is used for filtering visible light entering the objective lens (1); the detector (3) is arranged behind the solar blind filter (2) and is used for imaging corona (10) ultraviolet light in the absence of illumination and background (9) ultraviolet light in the presence of illumination, and the circuit board (16) is connected with the detector (3) and is used for converting the background (9) into a background image (14), converting the corona (10) into a corona image (15) and superposing or fusing the background image (14) and the corona image (15).

2. The ultraviolet imager of claim 1, wherein: the ultraviolet illuminating lamp (4) is an LED lamp which is manufactured by adopting a GaN and AlN single-layer film of an atomic-scale control interface and has the wavelength of 232-270 nm.

3. The ultraviolet imager of claim 1, wherein: the objective lens (1) is an ultraviolet lens with a transmission peak value in a day blind zone of 0.24-0.28 mu m.

4. The ultraviolet imager of claim 1, wherein: the detector (3) comprises a refrigeration back lighting sCMOS or an ultraviolet ICCD.

5. An ultraviolet imager, comprising: the device comprises an objective lens (1), a beam splitter (5), a solar blind filter (2), a visible light filter (6), a first detector (11), a second detector (12), an image fusion plate (7) and a display screen (8); the objective lens (1) is a wide spectrum objective lens which can transmit light with the wavelength of 220-780 nm; the beam splitter (5) is arranged behind the objective lens (1) and is used for reflecting ultraviolet light and transmitting visible light; the solar blind optical filter (2) is arranged on the reflecting surface of the beam splitter (5) and is used for filtering visible light and transmitting ultraviolet light, and the solar blind optical filter (2) only transmits the ultraviolet light with the wavelength of 240-280 nm; the first detector (11) is arranged behind the solar blind filter (2) and is used for corona ultraviolet imaging; the visible light filter (6) is arranged on the transmission surface of the beam splitter (5) and is used for filtering ultraviolet light and transmitting visible light; the second detector (12) is arranged behind the visible light filter (6) and is used for visible light imaging; the image fusion plate (7) is connected with the first detector (11) and the second detector (12) respectively, and the image fusion plate (7) is used for processing and fusing images to obtain point-to-point fusion images; the display screen (8) is connected with the image fusion plate (7), and the display screen (8) is used for displaying the fusion image.

6. The ultraviolet imager of claim 5, wherein: the in-band transmittance of the solar blind filter (2) is 18-22%, and the out-of-band cut-off depth is OD 11-13.

7. The ultraviolet imager of claim 5, wherein: the first detector (11) and the second detector (12) comprise sCMOS, refrigerated back illuminated sCMOS or ultraviolet ICCD.

8. The ultraviolet imager of claim 5, wherein: the objective lens (1) has an average transmittance of 90-95% for light having a wavelength of 240-280 nm, and the objective lens (1) has an average transmittance of 70-75% for light having a wavelength of 380-780 nm.

9. The ultraviolet imager of claim 5, wherein: the visible light filter (6) can transmit light with the wavelength of 380-780 nm, and the transmittance is 94-96%.

10. The ultraviolet imager of claim 5, wherein: an image fusion plate (7) scales the image and performs point-to-point fusion of the target and background images to determine the location of the corona on the background.