Infrared module and its usage

Abstract

This invention relates to an infrared module, comprising a housing and an infrared lens. The infrared lens is rotatably mounted in the housing via a rotating shaft, the axis of which is perpendicular to the optical axis of the infrared lens. A lens driving mechanism is also provided to drive the infrared lens to rotate relative to the rotating shaft. A compensation wall is also provided in the housing, and the lens driving mechanism can drive the infrared lens to rotate so that it is opposite to the compensation wall. A method for using the infrared module is also provided. In this invention, shutter compensation / temperature uniformity correction operations of the infrared lens can be completed by providing a compensation wall within the housing. The structure is simple, eliminating the need for a separate shutter mechanism. This not only reduces the manufacturing cost, weight, and size of the infrared module, but also provides high reliability, simple operation, and suitability for automatic control.

Description

Technical Field

[0001] This invention belongs to the field of infrared module technology, specifically relating to an infrared module and a method for using the infrared module. Background Technology

[0002] Currently, the field of view of infrared modules is generally quite small; to obtain a large field of view, the common approach is as follows:

[0003] (1) A specially designed infrared lens with a large field of view. This method will significantly increase the manufacturing cost and the weight of the infrared module. Moreover, the edge imaging quality of such a large field of view infrared lens is poor.

[0004] (2) By combining several infrared modules with small field of view, the images acquired by these infrared modules with small field of view are stitched together to obtain an image with a large field of view; the combination of multiple infrared modules will also greatly increase the manufacturing cost, and the size and weight of the infrared equipment will also increase.

[0005] Furthermore, the shutters used in infrared modules are all operated by individual mechanisms, which can achieve temperature uniformity correction and ensure the imaging quality of the infrared modules. For infrared lenses with a large field of view, a larger shutter mechanism is required accordingly; when using several infrared modules with a small field of view, a corresponding number of shutter mechanisms are needed. Therefore, both of these methods will also incur higher manufacturing costs due to the shutter mechanism, increasing the size and weight of the infrared equipment. Summary of the Invention

[0006] This invention relates to an infrared module and a method of using the infrared module, which can at least solve some of the defects of the prior art.

[0007] This invention relates to an infrared module, comprising a housing and an infrared lens, wherein the infrared lens is rotatably mounted in the housing via a rotating shaft, the axis of the rotating shaft being perpendicular to the optical axis of the infrared lens; a lens driving mechanism is also provided accordingly for driving the infrared lens to rotate relative to the rotating shaft, and a compensation wall is also provided in the housing, wherein the lens driving mechanism can drive the infrared lens to rotate to be opposite to the compensation wall.

[0008] As one implementation method, under the action of the lens driving mechanism, the infrared lens has multiple image acquisition positions, and an image acquisition window is formed on the housing to meet the multi-position image acquisition requirements of the infrared lens.

[0009] As one implementation method, the image acquisition window is a trumpet-shaped window that gradually expands from the inside of the housing to the outside of the housing.

[0010] As one implementation method, under the driving action of the lens driving mechanism, the infrared lens has two image acquisition boundary positions; when the infrared lens is in the image acquisition boundary position, the corresponding side edge of the image acquisition window coincides with or is tangent to the field of view boundary of the infrared lens.

[0011] As one implementation method, the image acquisition window is a trapezoidal window, and the length direction of its outer opening is perpendicular to the axis of the rotation axis.

[0012] As one embodiment, a ribbon cable arrangement channel is formed in the housing, and the ribbon cable of the infrared lens extends out of the housing after being arranged through the ribbon cable arrangement channel. The ribbon cable arrangement channel can buffer a certain length of ribbon cable.

[0013] This invention also relates to a method of using the above-mentioned infrared module, including:

[0014] When temperature uniformity correction is required, the infrared lens is driven to rotate to face the compensation wall and acquire an image of the compensation surface to complete the temperature uniformity correction operation.

[0015] As one implementation method, the method of using the infrared module further includes: driving the infrared lens to rotate relative to a rotation axis, wherein the infrared lens acquires an image frame each time it generates an angular displacement, and the field of view of the infrared lens overlaps between two adjacent image acquisition positions.

[0016] The collected images are stitched together to obtain a panoramic image with a wide field of view.

[0017] As one implementation method, when stitching two adjacent frames of images, the feature information and relative rotation angle between the two adjacent frames of images are used to calculate the corresponding rotation matrix. Then, a projection transformation is performed based on the rotation matrix to rotate the two frames of images to the same plane. Finally, the stitching seam between the two frames of images is found and the images are stitched together.

[0018] As one implementation method, during image acquisition, the angular displacement generated by the infrared lens each time is smaller than the field of view of the infrared lens.

[0019] The present invention has at least the following beneficial effects:

[0020] In this invention, shutter compensation and temperature uniformity correction of the infrared lens can be completed by setting a compensation wall inside the housing. The structure is simple and does not require a separate shutter mechanism. This not only reduces the manufacturing cost, weight and volume of the infrared module, but also ensures that the shutter compensation function is highly reliable, easy to operate and suitable for automatic control. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 This is a schematic diagram of the structure of the infrared module provided in an embodiment of the present invention;

[0023] Figure 2 for Figure 1 A schematic diagram of the structure after removing the top cover;

[0024] Figure 3 This is an exploded view of the infrared module provided in an embodiment of the present invention;

[0025] Figure 4 This is a schematic diagram showing the installation of the infrared lens in the housing.

[0026] Figure 5 A schematic diagram illustrating shutter compensation operation of an infrared lens provided in an embodiment of the present invention;

[0027] Figure 6 and Figure 7 This is a schematic diagram of the activity path of an infrared lens provided in an embodiment of the present invention;

[0028] Figure 8 This is a flowchart illustrating the method of using the infrared module provided in an embodiment of the present invention. Detailed Implementation

[0029] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0030] Example 1

[0031] like Figures 1-4 This invention provides an infrared module, including a housing 1 and an infrared lens 2. The infrared lens 2 is rotatably disposed in the housing 1 via a rotating shaft, the axis of which is perpendicular to the optical axis of the infrared lens 2. Correspondingly, a lens driving mechanism 4 is also provided to drive the infrared lens 2 to rotate relative to the rotating shaft.

[0032] like Figures 3-5The housing 1 also includes a compensation wall 15, and the lens drive mechanism 4 can drive the infrared lens 2 to rotate so that it is opposite to the compensation wall 15. Based on this design, the shutter compensation operation / temperature uniformity correction operation of the infrared lens 2 can be completed by setting a compensation wall 15 inside the housing. The structure is simple, and there is no need for a separate shutter mechanism. This not only reduces the manufacturing cost, weight, and volume of the infrared module, but also ensures that the shutter compensation function is highly reliable, easy to operate, and suitable for automatic control.

[0033] Preferably, such as Figure 3 and Figure 4 By connecting a shutter compensation plate to one of the window plates 141, the aforementioned compensation wall 15 can be formed.

[0034] Furthermore, under the action of the lens driving mechanism, the infrared lens 2 has multiple image acquisition positions, and an image acquisition window 14 is formed on the housing 1 to meet the multi-position image acquisition requirements of the infrared lens 2.

[0035] Based on the above scheme, an infrared module with a small field of view can be used to obtain an image with a large field of view. For example, the field of view of the infrared module is in the range of 20° to 60°.

[0036] The aforementioned infrared lens 2 can rotate relative to the rotation axis in a certain direction. Because it can produce a certain angular displacement relative to the rotation axis, it can acquire images from different orientations (meaning the infrared lens 2 can acquire images from multiple image acquisition positions, all located on the same arc), thus expanding its image acquisition range and making it possible for the infrared module to obtain images with a large field of view. The axis of rotation is perpendicular to the optical axis of the infrared lens 2. More specifically, the axis of rotation is perpendicular to the plane formed by the rotation of the optical axis of the infrared lens 2. For example, when the axis of rotation is parallel to the vertical direction, the rotation direction of the aforementioned infrared lens 2 is parallel to the horizontal plane.

[0037] The image acquisition window 14 is preferably configured to meet the image acquisition path requirements of the infrared lens 2 within a set image acquisition range. Preferably, the image acquisition window 14 is a trumpet-shaped window that gradually expands from the inside of the housing 1 to the outside, which better adapts to the rotational movement characteristics and image acquisition features of the infrared lens 2. In one embodiment, such as... Figures 1-4 The image acquisition window 14 is a trapezoidal window, and the length direction of its outer opening is perpendicular to the axis of the rotation axis.

[0038] Optionally, such as Figures 1-4The front end of the housing 1 adopts a frame structure, and window plates 141 are connected to the two short edges of the frame structure respectively. The two window plates 141 extend towards the inside of the housing 1, thereby forming the trapezoidal window that gradually expands from the inside to the outside as described above.

[0039] Furthermore, under the driving action of the lens driving mechanism 4, the infrared lens 2 has two image acquisition boundary positions; when the infrared lens 2 is in the image acquisition boundary position, the corresponding side edge of the image acquisition window 14 coincides with or is tangent to the field of view boundary of the infrared lens 2. In some cases, the image acquisition boundary of the infrared lens 2 can also be defined by the image acquisition window 14.

[0040] In the above-described scheme of setting window plate 141, when the window plate 141 is rotatable (for example, the outer side of the window plate 141 is hinged to the corresponding short edge, or the inner side of the window plate 141 is rotatably set in the housing 1), the image acquisition window 14 is formed as a window with an adjustable cross section. In conjunction with the rotational movement of the infrared lens 2, it can not only help to adjust the field of view, but also improve the imaging quality of the infrared lens 2.

[0041] Preferably, a rotating bracket 21 is provided in the housing 1, the rotating bracket 21 is connected to the rotating shaft, and the infrared lens 2 is mounted on the rotating bracket 21.

[0042] In one embodiment, such as Figure 2 and Figure 3 The aforementioned lens drive mechanism 4 includes a drive motor and a transmission structure, the transmission structure including but not limited to a gear set 41.

[0043] More preferably, the drive motor is a stepper motor, which can make the infrared lens 2 rotate according to the set angular displacement, ensuring the control accuracy of the image acquisition position of the infrared lens 2 each time, thereby reducing the difficulty of subsequent image processing and improving the quality of large field-of-view images.

[0044] Furthermore, based on the aforementioned shutter compensation plate and window plate 141 settings, such as Figure 4 A cavity 17 is formed between the shutter compensation plate, the window plate 141 and the inner wall of the housing 1. The cavity 17 is used to install the aforementioned drive motor. This method can effectively improve the structural compactness of the infrared module and facilitate the miniaturization design of the infrared module.

[0045] In one embodiment, such as Figure 3An arc-shaped guide groove 16 is provided on the housing 1, and the infrared lens 2 is connected to a guide post (for example, the guide post can be connected to the aforementioned rotating bracket 21). The guide post slides within the arc-shaped guide groove 16, which on the one hand guides the rotational movement of the infrared lens 2, improving the smoothness and accuracy of the rotational movement of the infrared lens 2, and on the other hand constrains the rotational stroke of the infrared lens 2. The axis of the guide post is parallel to the axis of the rotation axis, and more preferably, the two are collinear.

[0046] In one embodiment, such as Figure 3 and Figure 4 The housing 1 contains a cable routing channel. The cable 22 of the infrared lens 2 extends out of the housing 1 after being routed through this channel. The cable routing channel can buffer a certain length of cable 22. Optionally, the cable routing channel can be formed by multiple cable guide rods 3. The axes of the cable guide rods 3 are parallel to the axis of rotation. The cable guide rods 3 are arranged in a staggered manner to constrain the cable 22 between them. Simultaneously, the cable 22 can be bent to achieve the purpose of buffering the cable 22. Based on the above design, it can be ensured that the cable 22 maintains a reliable following connection when the infrared lens 2 rotates.

[0047] like Figure 3 The housing 1 can be designed to include a housing body 11 and a top cover 12 and a rear cover 13 that are detachably connected to the housing body 11. For example, the top cover 12 and the rear cover 13 are fixed to the housing body 11 by screws or other means. The detachable top cover 12 facilitates the installation and maintenance of the gear set 41, and the detachable rear cover 13 facilitates the installation and maintenance of the infrared lens 2.

[0048] Example 2

[0049] like Figure 8 The present invention provides a method for using the above-mentioned infrared module, including:

[0050] Based on the setting of the compensation wall 15, when temperature uniformity correction is required, the infrared lens 2 is driven to rotate to be opposite the compensation wall 15 and to acquire an image of the compensation wall 15. Since the temperature of the compensation wall 15 is uniform, the temperature uniformity correction operation can be completed by acquiring an image of the compensation wall 15.

[0051] Furthermore, the method of using this infrared module also includes:

[0052] The infrared lens 2 is driven to rotate relative to a rotation axis. Each time the infrared lens 2 produces an angular displacement, it acquires an image frame. Between two adjacent image acquisition positions, the field of view of the infrared lens 2 overlaps.

[0053] The collected images are stitched together to obtain a panoramic image with a wide field of view.

[0054] This method can be implemented based on the infrared module provided in Embodiment 1 above.

[0055] like Figure 6 Infrared lens 2 first acquires one frame of image at the starting position, then rotates a certain angle and stops, acquiring another frame of image, until the angular displacement generated by infrared lens 2 reaches the set value. Figure 6 In the example shown, infrared lens 2 stays at the starting position (starting image acquisition point) for time t1 to acquire the first frame image. Then, it rotates for 22.5 ms and stops, producing an angular displacement of 22.5°, reaching the first intermediate image acquisition point. It stays at this point for time t2 to acquire the second frame image. It then rotates again for 22.5 ms and stops, producing an angular displacement of 22.5°, reaching the second intermediate image acquisition point. It stays at this point for time t3 to acquire the third frame image. It then rotates again for 22.5 ms and stops, producing an angular displacement of 22.5°, reaching the third intermediate image acquisition point. It stays at this point for time t4 to acquire the fourth frame image. Finally, it rotates again for 22.5 ms and stops, producing an angular displacement of 22.5°, reaching the ending image acquisition point. It stays at this point for time t5 to acquire the fifth frame image. This completes the image acquisition process, resulting in a 90° field-of-view image. The infrared lens 2 preferably stays at each image acquisition point for the same amount of time, for example, within the range of 80 to 120 ms.

[0056] After the image acquisition is completed, such as Figure 6 As shown, this can drive the infrared lens 2 to reset to the starting position.

[0057] exist Figure 7 In the process, after completing a round of large field-of-view image acquisition, the infrared lens 2 is driven to the shutter sampling position, so that the infrared lens 2 is facing the compensation wall 15. Since the temperature of the compensation wall 15 is uniform, the temperature uniformity correction operation can be completed by acquiring images facing the compensation wall 15. During exposure compensation, the infrared lens 2 stays at the shutter sampling position for a period of 80–120 ms. The angular displacement between the shutter sampling position and the starting / ending image acquisition point can be controlled within the range of 40–60°. When the lens drive mechanism 4 uses a stepper motor, this angular displacement is an integer multiple of the angular displacement between two adjacent image acquisition points. Figure 7In the example shown, the infrared lens 2 needs to undergo an angular displacement of 45° to move from the endpoint image acquisition point to the shutter sampling position, which is then driven to rotate for 45ms. After the temperature uniformity correction operation is completed, the infrared lens 2 is then driven to return to the starting position.

[0058] Preferably, during image acquisition, the angular displacement generated by the infrared lens 2 each time is smaller than the field of view of the infrared lens 2. This ensures that the field of view of the infrared lens 2 overlaps between two adjacent image acquisition positions, thereby improving the image stitching quality.

[0059] Preferably, such as Figure 8 When stitching two adjacent image frames, the feature information and relative rotation angle between the two frames are used to calculate the corresponding rotation matrix. Then, a projection transformation is performed based on the rotation matrix to rotate the two frames to the same plane. Finally, the stitching seam between the two frames is located and the images are stitched together. Furthermore, after performing the projection transformation on the two frames, exposure compensation is applied according to the actual situation before image stitching, which can improve image quality.

[0060] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. An infrared module, comprising a housing and an infrared lens, characterized in that: The infrared lens is rotatably mounted in the housing via a rotating shaft, the axis of which is perpendicular to the optical axis of the infrared lens. Correspondingly, a lens driving mechanism is also provided to drive the infrared lens to rotate relative to the rotating shaft. The housing is also provided with a compensation wall, and the lens driving mechanism can drive the infrared lens to rotate to be opposite the compensation wall. Specifically, a shutter compensation plate is connected to one of the window plates to form the compensation wall.

2. The infrared module as described in claim 1, characterized in that: Under the action of the lens driving mechanism, the infrared lens has multiple image acquisition positions, and the housing is formed with matching image acquisition windows to meet the multi-position image acquisition requirements of the infrared lens.

3. The infrared module as described in claim 2, characterized in that: The image acquisition window is a trumpet-shaped window that gradually expands from the inside of the housing to the outside.

4. The infrared module as described in claim 3, characterized in that: Under the driving action of the lens driving mechanism, the infrared lens has two image acquisition boundary positions; when the infrared lens is in the image acquisition boundary position, the corresponding side edge of the image acquisition window coincides with or is tangent to the field of view boundary of the infrared lens.

5. The infrared module as described in claim 3, characterized in that: The image acquisition window is a trapezoidal window, and the length direction of its outer opening is perpendicular to the axis of the rotation axis.

6. The infrared module as described in claim 1, characterized in that: A cable arrangement channel is formed in the housing. The cable of the infrared lens extends out of the housing after being arranged through the cable arrangement channel. The cable arrangement channel can buffer a certain length of cable.

7. The method of using the infrared module as described in any one of claims 1 to 6, characterized in that, include: When temperature uniformity correction is required, the infrared lens is driven to rotate to face the compensation wall and acquire an image of the compensation wall to complete the temperature uniformity correction operation.

8. The method of using the infrared module as described in claim 7, characterized in that, include: An infrared lens is driven to rotate relative to a rotation axis. Each time the infrared lens produces an angular displacement, it acquires an image frame. Between two adjacent image acquisition positions, the field of view of the infrared lens overlaps. The collected images are stitched together to obtain a panoramic image with a wide field of view.

9. The method of using the infrared module as described in claim 8, characterized in that, When stitching two adjacent frames together, the feature information and relative rotation angle between the two adjacent frames are used to calculate the corresponding rotation matrix. Then, a projection transformation is performed based on the rotation matrix to rotate the two frames to the same plane. Finally, the stitching seam between the two frames is found and the images are stitched together.

10. The method of using the infrared module as described in claim 8, characterized in that, During image acquisition, the angular displacement generated by the infrared lens each time is smaller than the field of view of the infrared lens.

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