Infrared optical system for active-passive composite probing

Abstract

The present disclosure provides an infrared optical system for active and passive composite detection, and relates to the field of photoelectric detection, which comprises a shell, an infrared imaging mechanism comprising an infrared frame and an infrared lens group, the infrared frame is arranged in the shell, the infrared lens group is arranged in the infrared frame to form an infrared channel, and the infrared lens group is used for passive imaging of a target object; a laser detection mechanism comprising a laser frame and a laser lens group, the laser frame is arranged in the infrared frame in a separable manner, the laser lens group is arranged in the laser frame to form a laser channel, and the laser lens group is used for measuring the angle and distance of the target object; wherein the laser lens group and the infrared lens group are arranged eccentrically. The laser infrared composite detection optical system has the effects of small volume, light weight and low manufacturing cost.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of photoelectric detection, and particularly relates to an infrared optical system for active and passive composite detection. BACKGROUND

[0002] In the field of photoelectric detection, photoelectric detection systems need to have very long action distance and high-resolution imaging performance, and need to meet the requirements of high integration and small size. In order to meet the requirements of miniaturization and intelligentization of photoelectric detection equipment, integrating multiple detection methods in a limited space can effectively improve the detection capability and anti-interference capability. Active laser detection has long detection distance and high detection accuracy; infrared imaging can achieve passive imaging in all-weather. The two detection methods complement each other to obtain more target and background information, and can improve the anti-interference capability of the detection system, which has very high application value.

[0003] The current laser infrared composite detection optical system uses a split design or a coaxial design with a common aperture. For the split design, an infrared optical system and a laser optical system are placed in the same structural member, usually in an up-down or left-right manner. This design is simple to assemble and adjust, but has the disadvantages of large size and high cost, which cannot meet the miniaturization requirements of photoelectric detection systems. For the coaxial design with a common aperture, a common lens group is often used to transmit laser and infrared signals, and then a beam splitter is used to separate the laser and infrared signals, so that the laser and infrared signals pass through the laser lens group and the infrared lens group, respectively. This design uses a large number of lenses, which makes the optical system heavy and costly, and the assembly and adjustment are very difficult. SUMMARY

[0004] In view of the above problems, the present disclosure provides an infrared optical system for active and passive composite detection to improve the problems of large size, heavy weight and high cost of the laser infrared composite detection optical system.

[0005] One aspect of the present disclosure provides an infrared optical system for active and passive composite detection, comprising: a housing; an infrared imaging mechanism comprising an infrared frame and an infrared lens group, the infrared frame being arranged in the housing, the infrared lens group being arranged in the infrared frame to form an infrared channel, the infrared lens group being combined with an infrared detector for passive imaging of a target object; a laser detection mechanism comprising a laser frame and a laser lens group, the laser frame being arranged in the infrared frame in a separable manner, the laser lens group being arranged in the laser frame to form a laser channel, the laser lens group being combined with a laser detector for measuring the angle and distance of the target object; wherein the laser lens group and the infrared lens group are arranged eccentrically

[0006] Optionally, the infrared mirror assembly includes a first primary mirror, a first secondary mirror, and a first lens arranged sequentially along the incident direction of the light; the first primary mirror is used to converge the incident light onto the surface of the first secondary mirror; the first secondary mirror and the first lens are used to correct and eliminate spherical aberration, aberration, and coma of the incident light before imaging it onto the photosensitive surface of the infrared detector.

[0007] Optionally, the laser mirror assembly includes a filter, a second primary mirror, and a second secondary mirror arranged sequentially along the incident direction of the light. The filter is used to bandpass filter the incident light to obtain light of a specific wavelength band, and the second primary mirror and the second secondary mirror are used to correct and eliminate aberrations of the light of the specific wavelength band before it is detected by the photosensitive surface of the laser detector.

[0008] Optionally, the laser frame is located between the first primary mirror and the first secondary mirror.

[0009] Alternatively, the laser frame is mounted to the infrared frame using multiple screws.

[0010] Optionally, the infrared frame has an internal thread, and the laser frame has an external thread, with the external thread and the internal thread being threaded together.

[0011] Optionally, the distance D between the central axis of the laser channel and the central axis of the infrared channel satisfies the following relationship:

[0012]

[0013] in, The aperture of the laser channel. This refers to the aperture of the infrared channel.

[0014] Optionally, the aperture of the laser channel It is 30.5mm, and the aperture of the infrared channel is It is 150mm.

[0015] Optionally, the first primary mirror, the first secondary mirror, and the first lens are all fixed within the infrared frame by a retaining ring; the filter, the second primary mirror, and the second secondary mirror are all fixed within the laser frame by a retaining ring.

[0016] Optionally, the side of the first primary mirror furthest from the infrared detector protrudes from the laser frame.

[0017] The at least one technical solution used in the embodiments of this disclosure has at least the following beneficial effects:

[0018] The laser detection mechanism and the infrared imaging mechanism are independently arranged in the system, which can be used simultaneously to perform passive infrared imaging and active laser detection on the target object, the two detection modes are complementary to obtain more target information, and the anti-interference capability of the system is effectively improved; the system can also work independently to perform passive infrared imaging or active laser detection, and the practicability of the system is improved.

[0019] By arranging the laser detection mechanism in the infrared imaging mechanism and arranging the laser lens group and the infrared lens group in a decentered manner, the system can meet the demand of integrating multiple detection functions in a limited space while ensuring the normal operation of infrared imaging and laser detection, and the system is miniaturized.

[0020] Arranging the laser detection mechanism in the infrared imaging mechanism can reduce the number of lenses used, and the system is free of cemented lenses, which facilitates the processing, testing and adjustment of the system, effectively reduces the volume and weight of the system, reduces the cost, and meets the requirements of miniaturization and intelligentization of photoelectric detection equipment.

[0021] By controlling the distance between the laser channel and the infrared channel, the heat generated by the laser channel during operation is reduced, the thermal noise generated by the laser channel during operation is effectively avoided, and the infrared imaging quality is ensured.

[0022] The separable design of the laser detection mechanism and the infrared imaging mechanism enables the laser detection mechanism or the infrared imaging mechanism in the system to be replaced, modified and maintained at will, and the applicability of the system is enhanced. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to more completely understand the present disclosure and its advantages, reference will now be made to the following description taken together with the accompanying drawings, in which:

[0024] Figure 1 The overall structure of the infrared optical system for active and passive composite detection provided by the embodiment of the present disclosure is schematically shown;

[0025] Figure 2 The cross-sectional structure along the A-A line in the infrared imaging mechanism is schematically shown; Figure 1

[0026] Figure 3 The side view of the infrared optical system for active and passive composite detection provided by the embodiment of the present disclosure is schematically shown;

[0027] Figure 4 The infrared waveband MTF curve of the infrared imaging mechanism in the infrared optical system for active and passive composite detection provided by the embodiment of the present disclosure is schematically shown;

[0028] Figure 5 ​The laser waveband spot diagram measured by the laser detection mechanism in the infrared optical system for active and passive composite detection provided by the embodiment of the present disclosure is schematically shown.

[0029] [Legend of the drawing]

[0030] 1 - shell; 2 - infrared imaging mechanism; 21 - infrared frame; 22 - infrared lens group; 221 - first primary mirror; 222 - first secondary mirror; 223 - first lens; 224 - infrared detector; 23 - infrared channel; 3 - laser detection mechanism; 31 - laser frame; 32 - laser lens group; 321 - filter; 322 - second primary mirror; 323 - second secondary mirror; 324 - laser detector; 33 - laser channel; 4 - screw; 5 - compression ring. DETAILED DESCRIPTION

[0031] To make the objectives, technical solutions and advantages of the present disclosure clearer, further detailed description will be made to the present disclosure in combination with specific examples and with reference to the drawings. Obviously, the described examples are part of the examples of the present disclosure, rather than all the examples. Based on the examples in the present disclosure, all other examples obtained by those skilled in the art without making any creative effort fall within the scope of protection of the present disclosure.

[0032] The terms used herein are merely used to describe specific examples, and are not intended to limit the present disclosure. The terms "comprise", "contain", etc. used herein indicate the existence of the stated features, steps, operations and / or components, but do not exclude the existence or addition of one or more other features, steps, operations or components.

[0033] In the present disclosure, unless otherwise explicitly specified and limited, the terms "mount", "connect", "connection", "fix", etc. should be understood in a broad sense, for example, can be fixed connection, or detachable connection, or integral; can be mechanical connection, or electrical connection, or can be in communication with each other; can be direct connection, or indirect connection through intermediate medium, or internal communication of two elements or interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the present disclosure can be understood according to the specific circumstances.

[0034] In the description of the present disclosure, it should be understood that the orientation or positional relationship indicated by the terms "longitudinal", "length", "circumferential", "front", "back", "left", "right", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present disclosure and simplifying the description, and does not indicate or imply that the indicated subsystem or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present disclosure.

[0035] Throughout the drawings, the same or like reference numerals are used for the same or like elements of the application. The conventional arrangements or configurations can be omitted, in case causing confusion to the understanding of the present application. Also, the shape, size, positional relation of the components in the drawings do not reflect the actual size, scale and actual positional relation. In addition, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. For the sake of clarity, the figures can not be to scale.

[0036] Similarly, to simplify the present application and to help understand one or more of the various disclosed aspects, in the above description of the exemplary embodiments of the present application, various features of the present application are sometimes grouped together in a single embodiment, figure or description of the embodiments. Descriptions of the same or similar elements in several embodiments or descriptions of the same or similar elements in the same embodiment are not intended to suggest that the elements are the same or similar unless explicitly stated otherwise. Descriptions of the same or similar elements in several embodiments or descriptions of the same or similar elements in the same embodiment are not intended to suggest that a single feature should be used exclusively with only one embodiment or that a feature described with one embodiment can not be implemented with other embodiments even though the other embodiments are not explicitly described. In some embodiments, well-known structures have not been described in detail or have been presented only in block diagram form. Furthermore, the describing of a particular feature or structure as being implanted with an embodiment does not indicate that the structure and feature are essential for that embodiment, and variations of that embodiment can lack the structure and feature.

[0037] In addition, the terms "first", "second", etc. are used only for descriptive purposes and do not constitute a limitation on the scope of the application or imply that the indicated elements must be employed in only one order rather than in other orders. Accordingly, the identification of components with "first", "second", etc. does not constitute a limitation on the scope of the application or imply that multiple components must necessarily be employed in only one order rather than in other orders, and / or cannot be simultaneously employed. The terms "plurality" and "a plurality", as well as "multiple" or "a multiple", mean "more than one", unless explicitly indicated to the contrary.

[0038] The embodiments of the present disclosure provide an infrared optical system for active and passive composite detection.

[0039] Figure 1 The overall structure schematic diagram of the infrared optical system for active and passive composite detection is schematically shown according to the embodiments of the present disclosure; Figure 2 The cross-sectional structure schematic diagram along the A-A line of the infrared optical system for active and passive composite detection is schematically shown. Figure 1 The cross-sectional structure schematic diagram along the A-A line of the infrared optical system for active and passive composite detection is schematically shown.

[0040] Referring to Figure 1 and Figure 2 The infrared optical system for active and passive composite detection comprises a housing 1, an infrared imaging mechanism 2 and a laser detection mechanism 3.

[0041] According to the embodiments of the present disclosure, the infrared imaging mechanism 2 comprises an infrared frame 21 and an infrared lens group 22, the infrared frame 21 is fixedly installed in the housing 1, the infrared lens group 22 is arranged in the infrared frame 21 to form an infrared channel 23, and the infrared lens group 22 is combined with an infrared detector 224 to perform passive imaging on a target object.

[0042] The infrared lens set 22 includes a first primary mirror 221, a first secondary mirror 222 and a first lens 223 arranged in sequence along the light incident direction, and the first primary mirror 221, the first secondary mirror 222 and the first lens 223 are fixedly installed in the infrared frame 21 by the pressing ring 5. An extension frame (indicated by a dashed line in the figure) is externally connected to the infrared frame 21 away from the first primary mirror 221, and the infrared detector 224 is fixedly installed in the extension frame. The first primary mirror 221 is used to converge the incident light to the surface of the first secondary mirror 222. The first secondary mirror 222 and the first lens 223 are used to correct and eliminate spherical aberration, aberration and coma of the incident light, and then image to the photosensitive surface of the infrared detector 224.

[0043] For example, the infrared detector 224 is an infrared focal plane detector, and the designer can select the type of the infrared detector 224 according to the actual work requirement, and the type of the infrared detector 224 is not specifically limited in the embodiment of the present disclosure.

[0044] The infrared channel 23 detection process: the incident light of the infrared wave band is converged to the surface of the first secondary mirror 222 through the first primary mirror 221, and then the light is corrected and eliminated by the first secondary mirror 222 and the first lens 223 to eliminate a series of spherical aberration, aberration and coma, and then the light is imaged to the photosensitive surface of the infrared detector 224.

[0045] Referring to Figure 1 and Figure 2 According to the embodiment of the present disclosure, the laser detection mechanism 3 includes a laser frame 31 and a laser lens set 32. The laser frame 31 is arranged on one side of the infrared frame 21 in a separable manner, and the first primary mirror 221 protrudes from the laser frame 31 on the side away from the infrared detector 224. A notch capable of accommodating the laser frame 31 is excavated on one side of the first primary mirror 221, and the laser frame 31 is located between the first primary mirror 221 and the first secondary mirror 222. The laser lens set 32 is arranged in the laser frame 31 to form a laser channel 33. The laser lens set 32 is arranged eccentrically with the infrared lens set 22.

[0046] The laser lens set 32 is combined with the laser detector 324 to measure the angle and distance of the target object. The laser lens set 32 includes a filter 321, a second primary mirror 322 and a second secondary mirror 323 arranged in sequence along the light incident direction, and the filter 321, the second primary mirror 322 and the second secondary mirror 323 are fixedly installed in the laser frame 31. The laser detector 324 is installed on the side of the laser frame 31 away from the filter 321.

[0047] The filter 321 is used to perform band-pass filtering on the incident light to obtain light of a specific wave band. The second primary mirror 322 and the second secondary mirror 323 are used to correct and eliminate aberration of the light of the specific wave band, and then detect the light on the photosensitive surface of the laser detector 324.

[0048] It should be noted that the laser frame 31 is mounted on the infrared frame 21 by a plurality of screws 4 in the embodiment of the present disclosure. In other embodiments, the infrared frame 21 can be provided with internal threads, and the laser frame 31 can be provided with external threads, and the external threads and the internal threads can be threadedly assembled.

[0049] In the embodiment of the present disclosure, the laser detection mechanism 3 is used as an example to be combined with the infrared imaging mechanism 2. Since the laser detection mechanism 3 and the infrared imaging mechanism 2 are independently and separately arranged in the embodiment of the present disclosure, the laser detection mechanism 3 in the present disclosure can be replaced by a visible light detection component to realize simultaneous infrared and visible light detection. Meanwhile, when any one of the laser detection mechanism 3 and the infrared imaging mechanism 2 needs to be maintained or modified, it can be maintained or modified separately.

[0050] Figure 3 A side view of the infrared optical system for active and passive composite detection provided by the embodiment of the present disclosure is schematically shown.

[0051] Referring to Figure 2 and Figure 3 According to the embodiment of the present disclosure, in order to reduce the influence of heat generated by the laser detection mechanism 3 on the working of the infrared imaging mechanism 2 when the laser detection mechanism 3 works, so as to ensure the imaging quality of the infrared imaging mechanism 2. The distance D between the central axis of the laser channel 33 and the central axis of the infrared channel 23 satisfies the following relationship:

[0052]

[0053] In the embodiment of the present disclosure, is the light passing aperture of the laser channel 33, is the light passing aperture of the infrared channel 23.

[0054] According to the embodiment of the present disclosure, the light passing aperture of the laser channel 33 is 30.5 mm, and the light passing aperture of the infrared channel 23 is 150 mm.

[0055] Figure 4 An infrared waveband MTF curve measured by the infrared imaging mechanism in the infrared optical system for active and passive composite detection provided by the embodiment of the present disclosure is schematically shown. Figure 5 A laser waveband point array diagram measured by the laser detection mechanism in the infrared optical system for active and passive composite detection provided by the embodiment of the present disclosure is schematically shown.

[0056] Referring to Figure 4 and Figure 5 In order to verify the imaging quality of the infrared imaging mechanism 2 and the accuracy of the laser detection mechanism 3 in the embodiment of the present disclosure. For the infrared channel 23, the modulation transfer function (MTF) is used to evaluate the image quality of the infrared waveband. From the MTF curve of the infrared waveband shown in FIG. 6, it can be seen that the MTF of the infrared waveband is greater than 0.5 at the spatial frequency of 50 lp / mm, which meets the imaging quality requirement of the infrared waveband.Figure 4 As can be seen from the optical system, the image quality of the infrared channel 23 approaches the diffraction limit, so the infrared imaging mechanism 2 in the system performs better in the process of meeting the infrared and laser simultaneous detection, and can be popularized and applied.

[0057] For the laser channel 33, the spot diagram is a simple, intuitive and easy-to-use image quality evaluation method. Figure 5 is a schematic diagram of the spot under the sampling field of view of the laser channel 33 in the optical system. Figure 5 As can be seen from the optical system, the image quality of the infrared channel 23 approaches the diffraction limit, so the infrared imaging mechanism 2 in the system performs better in the process of meeting the infrared and laser simultaneous detection, and can be popularized and applied.

[0058] The above specific embodiments further illustrate the technical solutions of the present application, and it should be understood that the above description is only a specific embodiment of the present application and is not intended to limit the present application. Any modification, equivalent replacement, improvement, etc. within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. An infrared optical system for combined active and passive detection, characterized in that, include: Shell (1); The infrared imaging mechanism (2) includes an infrared frame (21) and an infrared mirror group (22). The infrared frame (21) is disposed inside the housing (1), and the infrared mirror group (22) is disposed inside the infrared frame (21) to form an infrared channel (23). The infrared mirror group (22) is combined with an infrared detector (224) for passive imaging of the target object. The laser detection mechanism (3) includes a laser frame (31) and a laser mirror group (32). The laser frame (31) is detachably disposed within the infrared frame (21). The laser mirror group (32) is disposed within the laser frame (31) to form a laser channel (33). The laser mirror group (32) is combined with a laser detector (324) to measure the angle and distance of the target object. The laser mirror group (32) and the infrared mirror group (22) are arranged eccentrically.

2. The infrared optical system for active-passive combined detection according to claim 1, characterized in that, The infrared mirror group (22) includes a first primary mirror (221), a second primary mirror (222), and a first lens (223) arranged sequentially along the incident direction of light. The first primary mirror (221) is used to converge the incident light onto the surface of the first primary mirror (222); the first primary mirror (222) and the first lens (223) are used to correct and eliminate spherical aberration, aberration and coma of the incident light before imaging the photosensitive surface of the infrared detector (224).

3. The infrared optical system for active-passive combined detection according to claim 2, characterized in that, The laser mirror assembly (32) includes a filter (321), a second primary mirror (322), and a secondary mirror (323) arranged sequentially along the incident direction of light. The filter (321) is used to bandpass filter the incident light to obtain light of a specific wavelength. The second primary mirror (322) and the second secondary mirror (323) are used to correct and eliminate aberrations of the light of the specific wavelength and then image it onto the photosensitive surface of the laser detector (324) for detection.

4. The infrared optical system for active-passive combined detection according to claim 2, characterized in that, The laser frame (31) is located between the first primary mirror (221) and the first secondary mirror (222).

5. The infrared optical system for active-passive combined detection according to claim 1, characterized in that, The laser frame (31) is mounted on the infrared frame (21) by a plurality of screws (4).

6. The infrared optical system for active-passive combined detection according to claim 1, characterized in that, The infrared frame (21) has an internal thread, and the laser frame (31) has an external thread, and the external thread is threadedly assembled with the internal thread.

7. The infrared optical system for active-passive combined detection according to claim 1, characterized in that, The distance D between the central axis of the laser channel (33) and the central axis of the infrared channel (23) satisfies the following relationship: where is the aperture of the laser channel (33) and is the aperture of the infrared channel (23).

8. The infrared optical system for active-passive combined detection according to claim 7, characterized in that, The aperture of the laser channel (33) is 30.5 mm, and the aperture of the infrared channel (23) is 150 mm.

9. The infrared optical system for active-passive combined detection according to claim 3, characterized in that, The first primary mirror (221), the first secondary mirror (222), and the first lens (223) are all fixed inside the infrared frame (21) by a pressure ring (5); The filter (321), the second primary mirror (322), and the second secondary mirror (323) are all fixed inside the laser frame (31) by a pressure ring (5).

10. The infrared optical system for active-passive combined detection according to claim 2, characterized in that, The first primary mirror (221) is positioned on the side away from the infrared detector (224) that protrudes from the laser frame (31).

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