RU2746089C1 - Detection device for optical and optoelectronic devices - Google Patents

Abstract

FIELD: optoelectronic instrumentation.

SUBSTANCE: invention relates to the field of optoelectronic instrumentation and relates to a device for detecting optical and optoelectronic devices. The device contains a surveillance device, a rangefinder device and a detection device. The detection device contains a transmitting unit with a laser emitter and a telescope and a receiving unit made in the form of a two-channel imaging system with separate registration of s- and p-polarization with the same angular fields. The receiving unit contains a lens, a polarizing divider, a compensator for beams with p-polarization, a polarizer and a photodetector for separate registration of images with s- and p-polarizations. The polarizing divider is made in the form of a prism with a polarizing coating and a plate. The compensator is made in the form of a spherical lens or several lenses. The sensitive area of ​​the photodetector is divided into unequal zones, the interband boundary is shifted by Δ, the boundary of the second channel is shifted by 2Δ where Δ is the area of ​​overlapping images of the two channels at the border of the zones. The focal length of the second channel is reduced while maintaining the angular field.

EFFECT: technical result consists in eliminating the imposition of images at the border between the channels, improving the quality of the images and increasing the accuracy of determining the coordinates of the detected targets.

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Description

The invention relates to optoelectronic instrumentation and can be used in survey search optoelectronic laser ranging systems using the principle of reflection of radiation from the object under study.

There is a known device for detecting optoelectronic objects, described in patent RU No. 2129287, IPC G01S 17/00, published in 1999. The device contains a series-connected lens, an electro-optical converter, a gate pulse unit, the output of which is connected to the input of an image intensifier, a photodetector and a video control device (monitor), pulse-frequency laser, modulator and divider of frame frequency, sync generator, video signal processing unit.

Known is a device for detecting optoelectronic objects, described in patent RU No. 2349929, IPC G01S 17/00, published in 2009. The device contains a lens, an electro-optical converter, a photodetector, a television processing unit, a video control unit, a sync generator, a frame rate divider, modulator, pulsed laser, objective, block of gate pulses, control panel, laser with "knife" radiation pattern. The disadvantage of these devices is the use of image intensifier tubes, which are highly sensitive to local light interference (bright flashes of light, headlights of a car, open fire, other bright flashes of light), as a result, the observation range is reduced. Also, the "back" illumination of the night vision device by the radiation of an IR illuminator, scattered by atmospheric inhomogeneities, large dimensions and weight limit the scope of this device.

Exceeding the specified threshold by the video signal is equated in these devices to the fact that an optical device appears in the irradiation zone. The known devices have significant drawbacks, especially when detecting OP against a masking background of diffusely reflecting objects: walls of houses, mountains, forest, bushes, soil (when detecting OP from aircraft). Since in this case the total area of the diffuse object illuminated by the laser beam significantly exceeds the OP aperture, the level of the signal reflected from the OP becomes comparable to the level of the signal reflected from the diffuse object. When the threshold is set to a low level, the probability of a "false" triggering due to a signal from a diffuse object increases; when the threshold is set to a high level, the probability of the signal passing from the OP increases.

Closest to the claimed, selected for the prototype, is a device for detecting optical and optoelectronic devices (RF patent No. 2568336 from 1.11.13, IPC G01S 17/06).

где b - межосевое расстояние между зонами на чувствительной площадке фотоприемного устройства; устройство дальномерное, содержащее блоки передающий и приемный; электронный блок управления и обработки.A device for detecting optical and optoelectronic devices by scanning the positioned space, contains an observation device for displaying the positioned space; a detection device containing a transmitting unit made in the form of an illumination channel with a laser emitter, optically coupled with a telescope forming laser radiation, and a receiving unit in the form of a two-channel imaging system with s- and p-polarizations with the same angular fields, containing a lens, a polarization divider and a photodetector with a two-zone sensitive area for separate registration of images with s- and p-polarizations, a polarization divider in the form of gluing from an AR-90 ° prism or a BS-0 ° prism with an applied polarization coating and a plate, a compensator installed behind the polarization divider for rays with p-polarization, the polarizer is in front of the photodetector, the thickness of the polarization divider plate is

where b is the center distance between the zones on the sensitive area of the photodetector; a rangefinder device containing transmitting and receiving units; electronic control and processing unit.

The known device uses a two-channel imaging system with separate registration of reflected radiation recorded in different states of polarization on a two-zone sensitive area of the photodetector.

The focal lengths, angular fields and, accordingly, the linear fields of the channels are equal. Due to the small distances between the channels, which is determined by the size of the receiver, vignetting of oblique beams occurs at the border between the two channels and the images are superimposed on each other, which reduces the angular fields in the channels, complicates the processing of the results. When images are superimposed, the level of the signal reflected from the OP decreases and becomes comparable to the level of the signal reflected from the diffuse object. When the threshold is set to a low level, the probability of a "false" triggering due to a signal from a diffuse object increases; when the threshold is set to a high level, the probability of the signal passing from the OP increases.

The objective of the invention is to create a device for detecting OP with increased operational characteristics due to the construction in a two-channel system of a high-quality picture of images without overlapping at the border between the channels.

With the help of the proposed invention, the technical result is achieved, which consists in building a high-quality picture of images in a two-channel system without overlapping at the border between channels, in increasing the accuracy of determining the coordinates of detected targets at the border between channels, increasing the stability of parameters, increasing the detection efficiency of optical and optoelectronic devices on border between channels, improving performance.

где b - межосевое расстояние между зонами на чувствительной площадке фотоприемного устройства; устройство дальномерное, содержащее блоки передающий и приемный; электронный блок управления и обработки, отличающееся тем, что компенсатор выполнен в виде одной сферической линзы или нескольких линз, чувствительная площадка фотоприемного устройства разделена на неравные зоны, межзонная граница смещена на Δ, граница второго канала - на 2Δ, фокусное расстояние второго канала уменьшено при сохранении углового поля, где Δ - область наложения изображений двух каналов на границе зон.The problem is solved in that the known device for detecting optical and optoelectronic devices by scanning the positioned space, containing an observation device for displaying the positioned space; a detection device containing a transmitting unit made in the form of an illumination channel with a laser emitter, optically coupled with a telescope generating laser radiation, and a receiving unit in the form of a two-channel imaging system with separate registration of s- and p-polarizations with the same angular fields, containing a lens, polarization divider and a photodetector with a two-zone sensitive area for separate registration of images with s- and p-polarizations, a polarization divider in the form of gluing from an AR-90 ° prism or BS-0 ° prism with an applied polarizing coating and a plate, a compensator installed behind the polarization a divider for beams with p-polarization, the polarizer is in front of the photodetector, the thickness of the polarization divider plate is

where b is the center distance between the zones on the sensitive area of the photodetector; a rangefinder device containing transmitting and receiving units; electronic control and processing unit, characterized in that the compensator is made in the form of one spherical lens or several lenses, the sensitive area of the photodetector is divided into unequal zones, the interband boundary is shifted by Δ, the border of the second channel - by 2Δ, the focal length of the second channel is reduced while maintaining angular field, where Δ is the area of overlapping images of two channels at the border of the zones.

FIG. 1 shows the sensitive area of the photodetector: a) the prototype and b) the proposed detection device, where I is the first and II are the second zones of the sensitive area, Δ is the area of overlapping images of the two channels at the border of the prototype zones, 2a is the linear field of the first and second zones of the prototype , (2a + Δ) and (2a-Δ) is the linear field, respectively, of the first and second zones of the proposed device, f ₁ is the focal length of the first and second zones of the prototype and the first zone of the proposed device, f ₂ is the focal length of the second zone of the proposed device. From FIG. 1 shows that the prototype has an overlap of images at the border between the two channels, and in the proposed device this overlap is eliminated.

The sizes of the zones of the sensitive area can be different depending on the selected size of the photodetector and the specified angular field. For the variant when the maximum angular field for each zone is set by the described circle in the zone, and the radius of the circle is equal to the product of the angular field Ω _max by the focal length of the zone f ₁ , the focal length of the second zone of the proposed device f ₂ is equal to:

f ₂ = (a-Δ / 2) / (Ω _poppy -Δ / 2f _1).

Consider the detection of optical and optoelectronic devices using the proposed device. FIG. 2 shows a block diagram of the proposed device, where:

1 - surveillance device:

1.1 - interference filter;

1.2 - lens;

1.3 - television camera;

1.4 - microdisplay;

1.5 - electronic vizier;

2 - detection device:

2.1 - transmitting unit:

2.1.1 - laser emitter;

2.1.2 - telescope of the laser emitter;

2.2 - receiving unit:

2.2.1 - interference filter;

2.2.2 - lens;

2.2.3 - polarization divider:

2.2.3.1 - AR-90 ° prism;

2.2.3.2 - plate;

2.2.4 - compensator in the form of two lenses;

2.2.5 - polarizer;

2.2.6 - photodetector;

3 - rangefinder device:

3.1 - transmitting unit:

3.1.1 - laser emitter;

3.1.2 - telescope;

3.2 - receiving unit:

3.2.1 - interference filter;

3.2.2 - lens;

3.2.3 - photodetector device;

4 - electronic control and processing unit.

The detection device for optical and optoelectronic devices consists of a surveillance device 1; detection devices 2; rangefinder device 3 and electronic control and processing unit 4.

Surveillance device 1 is intended for a visual survey of the surrounding area. The observation device consists of an interference filter 1.1, a lens 1.2, a television camera 1.3, a microdisplay 1.4 and an electronic sight 1.5.

Transmitting unit 2.1 of the detection device is designed to irradiate a selected volume of space and irradiate optical and optoelectronic devices.

The transmitting unit 2.1 of the detection device consists of a laser emitter 2.1.1 and a telescope of a laser emitter 2.1.2.

The telescope of the detection device 2.1.2 is designed to form the required directional pattern of the probing laser in the target space.

Receiving unit 2.2 of the detection device is designed to obtain images of glaring objects in the plane of the sensitive area of the photodetector. Structurally, the receiving unit is made in the form of a two-channel imaging system with the ability to carry out separate registration of images with s- and p-polarizations.

Receiving unit 2.2 of the detection device consists of an interference filter 2.2.1, a lens 2.2.2, a polarization divider 2.2.3, consisting of an AR-90 ° prism 2.2.3.1 and a plate 2.2.3.2, a compensator 2.2.4 in the form of two lenses, a polarizer 2.2.5 and photodetector 2.2.6.

Interference filter 2.2.1 consists of a filter that cuts off the short-wavelength part of the background radiation spectrum, and a special filter that cuts off the long-wavelength part of the spectrum.

Lens 2.2.2 of the receiving unit is designed to build and acquire images of distant glaring objects in the plane of the sensitive area of the photodetector.

Polarization divider 2.2.3 and compensator 2.2.4 are used to distinguish objects that glare under the influence of probing radiation from other objects observed through the observation device. The selection of objects illuminated by the probe radiation is due to the predominant state of polarization of the radiation reflected from these objects, in contrast to the predominantly unpolarized radiation coming from other observed objects.

Compensator 2.2.4 is designed to align the focusing planes of radiation with different polarization components, reduce the focal length in the second zone and reduce the size of the second zone of the sensitive area of the photodetector. The compensator is made in the form of one spherical lens or several glass lenses, for example, TF5 with a high refractive index.

где b - межосевое расстояние между зонами на чувствительной площадке фотоприемного устройства. Изменением толщины пластины поляризационного делителя можно варьировать межосевое расстояние между каналами в плоскости изображения.Structurally, the polarization divider 2.2.2 is a gluing of the AR-90 ° prism 2.2.3.1 with the applied polarizing coating and the plate 2.2.3.2. The thickness of the polarizing splitter plate is

where b is the center-to-center distance between the zones on the sensitive area of the photodetector. By varying the thickness of the polarizing splitter plate, the center distance between the channels in the image plane can be varied.

Предложенное устройство приведено на фиг. 3. Обозначения на фиг. 3 идентичны принятым на фиг. 2.Instead of a prism in a polarization divider, you can use a BS-0 ° prism. In this case, the optical axis of the lens of the detector receiving unit and the normal to the sensitive area of the photodetector are parallel. The polarizing divider will be a gluing of a BS-0 ° prism with a polarizing coating applied and a plate. The thickness of the polarizing splitter plate will also be equal to

The proposed device is shown in FIG. 3. The designations in FIG. 3 are identical to those adopted in FIG. 2.

Polarizer 2.2.5 is installed in front of the photodetector 2.2.6 and is designed to suppress interference.

The sensitive area of the photodetector 2.2.6 is divided into two unequal zones for separate registration of images with s- and p-polarizations.

Rangefinder device 3 is designed to determine the range to optical and optoelectronic devices and consists of a transmitting unit 3.1 and a receiving unit 3.2.

The transmitting unit of the rangefinder 3 consists of a laser emitter 3.1.1 and a telescope 3.1.2. The transmitting unit of the rangefinder device is designed to irradiate detected targets.

Telescope 3.1.2 of the transmitting unit is designed to form the required radiation pattern of the laser emitter in the target space.

Receiving unit 3.2 consists of interference filter 3.2.1, lens 3.2.2, photodetector device Z.2.3.

The receiving unit 3.2 of the rangefinder device is designed to receive reflected radiation from targets and determine the range to detected targets.

OP detection is carried out as follows.

By means of the observation device 1, a visual survey of the surrounding area is carried out. When inspecting the area, the area of the proposed location of optical and optoelectronic devices is determined.

Detection of optical and optoelectronic objects is carried out by locating a selected volume of space with plane-polarized laser radiation. The laser radiation of the transmitting unit 2.1 of the detector 2 forms the required directional pattern of the probing laser in the object space. Locate the selected volume of space where the proposed optical and optoelectronic device is located. The reflected radiation from objects is received by the receiving unit 2.2 of the detector 2 and is divided by its polarization divider 2.2.1 into two orthogonally polarized components, the first of which, the s-polarization, is reflected from the first element of the polarization divider, passes through the polarizer 2.2.5 and is focused on the first sensitive zone. 6 in the area of s-polarization, and the second component - p-polarization - passes the first element of the polarization divider, is reflected from the second element of the polarization divider, passes through the compensator 2.2.4 and is additionally focused when compensating the optical path, it is reduced focal length, passes the polarizer 2.2.5 and focuses into the second zone of the sensitive area of the photodetector 2.2.6 in the p-polarization zone. Due to the additional focusing of the second component in the compensator when compensating for the optical path, its focal length is reduced, and as a consequence, the linear field of this channel and the size of the second zone of the sensitive area of the photodetector, where it is focused, decrease. And there is no overlap of images at the border between the channels.

The signals from the first and second zones of the sensitive area of the photodetector 2.2.6 enter the electronic control and processing unit 4, in which a signal is generated proportional to the ratio of the intensity of the reflected radiation with the polarization plane, orthogonal to the polarization plane of the irradiating radiation to the reflected radiation intensity with the polarization plane coinciding with the plane of polarization of the irradiating radiation. The processing of the results is carried out taking into account the scale of images in the first and second zones, the pixel size and the number of pixels in the zones. When reflected from optical and optoelectronic devices, the polarization does not change. By the value of the generated signal in the electronic control and processing unit 4, a system of optical and optoelectronic devices is detected in the field of view. In the control and processing device 4, the coordinates of the detected targets are measured. On the monitor of the surveillance device 1, the corresponding zone of the detected targets is indicated. The target is brought into the central zone of the field of view of the observation device 1.

A command signal is given from the electronic control and processing unit 4 to turn on and operate the rangefinder device 3. The laser radiation of the transmitting unit 3.1 rangefinder 3 with the required directional pattern is directed to the detected targets. Reflected radiation from targets enters the receiving rangefinder unit. Measure the range to optical and optoelectronic devices. The results of measurements of the coordinates of targets and range are displayed on the monitor screen of the surveillance device 1.

By changing the thickness t of the plate 2.2.3.2 of the polarization divider 2.2.3, it is possible to vary the center-to-center distance between the channels in the image plane, which makes it possible to use any photodetector both in the form of a CCD matrix and in the form of multi-element linear CCD receivers with any number of elements.

The use of a BS-0 ° prism or an AR-90 ° prism in a polarization divider makes it possible to perform the optical axis of the objective and the normal to the sensitive area of the photodetector parallel or perpendicularly. This possibility allows you to vary the layout of the device in order to reduce the weight and overall dimensions of the device.

The use of additional focusing in the compensator when compensating for the optical path makes it possible to reduce the focal length and the linear field of the second channel; due to this, the size of the second zone of the photodetector platform decreases and there is no overlapping of images at the border between the channels.

Thus, a device for observing optical and optoelectronic devices is proposed, in which the receiving unit of the detection device is made in the form of a two-channel imaging system with the same angular fields with the ability to: carry out separate registration of images with s- and p-polarizations with different focal lengths of the channels and linear fields of the photodetector.

The use of the proposed device makes it possible to build a high-quality picture of images in a two-channel system without overlapping at the border between channels, to increase the detection efficiency of optical and optoelectronic devices by increasing noise immunity, and the accuracy of determining the coordinates of detected targets at the border between channels.

Claims (1)

A device for detecting optical and optoelectronic devices by scanning the positioned space, comprising an observation device for displaying the positioned space; a detection device containing a transmitting unit made in the form of an illumination channel with a laser emitter, optically coupled with a telescope generating laser radiation, and a receiving unit in the form of a two-channel imaging system with separate registration of s- and p-polarizations with the same angular fields, containing a lens, polarization divider and a photodetector with a two-zone sensitive area for separate registration of images with s- and p-polarizations, a polarization divider in the form of gluing from an AR-90 ° prism or BS-0 ° prism with an applied polarizing coating and a plate, a compensator installed behind the polarization a divider for beams with p-polarization, the polarizer is in front of the photodetector, the thickness of the polarization divider plate is

where b is the center distance between the zones on the sensitive area of the photodetector; a rangefinder device containing transmitting and receiving units; electronic control and processing unit, characterized in that the compensator is made in the form of one spherical lens or several lenses, the sensitive area of the photodetector is divided into unequal zones, the interband boundary is shifted by Δ, the border of the second channel - by 2Δ, the focal length of the second channel is reduced while maintaining angular field, where Δ is the area of overlapping images of two channels at the border of the zones.

Images