A camera for a projection device, a projection device

Abstract

The present invention aims to provide a camera for a projection device and a projection device, which are applied to the field of projection technology. The camera includes a lens, a lens mount assembled with the camera lens, a circuit board, and an image sensor connected to the circuit board. With a horizontal plane constructed through the center line of the camera lens, the relative positions of the image sensor and the camera lens are set such that one of the upper and lower regions on the side of the lens imaging plane in the horizontal plane is the image acquisition region, and the other is the non-image acquisition region. By changing the relative positions of the image sensor and the camera lens, the image acquisition region of the camera is changed, so that the effective pixels of the projected image captured by the camera are more, facilitating the subsequent processing of the image. Its structure is simple, and it can achieve the most ideal image acquisition effect with the smallest modification method, facilitating production and use, and having strong practicability.

Description

Technical Field

[0001] The present invention relates to the field of projection technology, and particularly to a camera for a projection device and a projection device. Background Art

[0002] A projector is a device that can project images or videos onto a screen. To avoid having half of an image projected onto the desktop during the projection process, an upper offset optical path is generally used. To make the projected image clear, for the image projected by the projector, a camera is needed to collect it and perform corresponding image processing, etc. In general, for ordinary cameras to form images, the center of the lens and the center line of the image sensor coincide. If a camera is needed on the projector to assist in focusing, trapezoidal correction of the image, image recognition, etc., there will be a situation where the optical path of the projected image and the image collected by the camera are not on the same optical path;

[0003] As Figure 1 shown, when the camera 15 is at the same angle as the lens, half of the image collected by the camera 15 is of the desktop 10. Obviously, the image 11 collected by the camera 15 is smaller than the projected image 12 of the projection device, which wastes half of the image pixels, or the image is not fully included, and image cropping is required later, increasing the processor overhead.

[0004] As Figure 2 shown, when a small-angle camera 15 is used, the field of view size of the camera image is similar to the size of the projector image. The camera needs to be rotated upward by an angle to include the projected image in the camera's field of view. Otherwise, the projector can only collect part of the projected image. As Figure 2 shown, only part of the image 12 collected by the camera 15 and the image 11 projected by the projection device is the same. However, after rotation, there will be a problem of trapezoidal distortion in the camera image. As Figure 3 shown, the projected image 11 is rectangular, while the image 12 collected by the camera is trapezoidal. This requires higher processor overhead for later trapezoidal correction of the image, and the algorithm will also cause image distortion. At the same time, since there is a rotation of the internal parts in this method, the mold development and processing difficulty of the projector are also higher, which is not convenient to use and has poor practicability. Summary of the Invention

[0005] To solve the above problems, the present invention aims to provide a camera for a projection device and a projection device, which solves the problem of additional image processing required when an existing camera is applied to a projector.

[0006] To achieve the above object, the technical solution adopted by the present invention is: to provide a camera for a projection device, including a camera lens 1, a lens holder 2 assembled with the camera lens 1, a circuit board 3, and an image sensor 4 connected to the circuit board 3. With the horizontal plane constructed through the center line of the camera lens, the relative positions of the image sensor 4 and the camera lens 1 are set so that one of the upper and lower regions on the horizontal plane on the imaging surface side of the camera lens 1 is the image acquisition area, and the other is the non-image acquisition area.

[0007] Preferably, the central axis L4 of the image sensor 4 is parallel to the central axis L1 of the camera lens 1, and the parallel distance between them is D, and D is not zero.

[0008] Preferably, the distance D is equal to the distance from the center point of the image sensor 4 to one of its sides.

[0009] Preferably, the phase plane size of the camera lens 1 is larger than the size of the image sensor 4.

[0010] Preferably, the phase plane size of the camera lens 1 is twice the size of the image sensor 4.

[0011] Preferably, the angle of the camera lens 1 is 40 - 80 degrees.

[0012] To solve the above problems, the present application also provides a projection device, including an optical engine 5 and the camera described in any one of the above.

[0013] Preferably, the center of the projection lens 6 of the optical engine 5 and the center of the camera lens 1 of the camera are on the same horizontal plane.

[0014] Preferably, the area of the image acquisition area of the camera is larger than the area of the projection area of the projection lens 6.

[0015] Preferably, the horizontal projection angle of the optical engine 5 is 20 - 70 degrees, and the vertical projection angle of the optical engine 5 is 15 - 45 degrees.

[0016] The beneficial effects of the present invention are as follows: The present invention aims to provide a camera for a projection device and a projection device. The camera includes a lens, a lens holder assembled with the camera lens, a circuit board, and an image sensor connected to the circuit board. With the horizontal plane constructed through the center line of the camera lens, the relative positions of the image sensor 4 and the camera lens 1 are set such that one of the upper and lower regions on the horizontal plane on the imaging surface side of the camera lens 1 is the image acquisition area, and the other is the non-image acquisition area. By simply changing the relative position between the image sensor and the camera lens, the image acquisition area of the camera is changed, so that the effective pixels of the projected image captured by the camera are more, facilitating subsequent image processing. Its structure is simple, and it can achieve the most ideal image acquisition effect with the least modification. Moreover, in the structural design of the projector, the placement of the camera module is easier, and the effective acquisition of the projected image can be achieved without adjusting the camera angle, which is convenient for production and use and has strong practicability. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a schematic structural diagram of the background art (1) of the present invention;

[0018] Figure 2 is a schematic structural diagram of incomplete acquisition in the background art (2) of the present invention;

[0019] Figure 3 is a schematic structural diagram of trapezoidal distortion in the background art (2) of the present invention;

[0020] Figure 4 is a schematic structural diagram of the camera according to Embodiment 1 of the present invention;

[0021] Figure 5 is a schematic diagram of the principle of forming the image acquisition area of a traditional camera in Embodiment 2 of the present invention;

[0022] Figure 6 is a schematic diagram of the principle of forming the image acquisition area of the camera of the present application in Embodiment 2 of the present invention;

[0023] Figure 7 is a plan view of the camera of the present application in Embodiment 3 of the present invention;

[0024] Figure 8 is a schematic structural diagram of the projection device in Embodiment 4 of the present invention;

[0025] Figure 9 is a schematic structural diagram of the projection device in Embodiment 4 of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part rather than all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0027] When ordinal numbers such as "first" and "second" are mentioned in the embodiments of the present invention, unless they actually express an order meaning according to the context, they should be understood as merely for distinction.

[0028] The specific implementation manners of the present invention will be described in detail below with reference to the accompanying drawings:

[0029] Embodiment 1

[0030] As Figure 4 shown, a camera for a projection device includes a camera lens 1, a lens mount 2 assembled with the camera lens 1, a circuit board 3, and an image sensor 4 connected to the circuit board 3. With a horizontal plane in the transverse direction constructed through the center line of the camera lens, the relative positions of the image sensor 4 and the camera lens 1 are set such that one of the regions above and below the horizontal plane on the imaging surface side of the camera lens 1 is an image acquisition region, and the other is a non-image acquisition region. As Figure 4It can be known that the image sensor 4 can collect external images through the lens 1. The relative position between the image sensor 4 and the camera lens 1 has a great influence on its image acquisition area. The specific relative position includes the distance between the image sensor 4 and the camera lens 1, whether their central axes coincide, how much they are offset from each other, and in what direction they are offset, etc. Of course, it should be understood that in the actual design process, based on the relevant knowledge in this field, various relevant parameters such as the size, thickness, focal length, transmittance, and material of the corresponding camera lens 1 will be selected, as well as the lens mount 2, circuit board 3, and the relevant size of the circuit board 3 that match it. Similarly, the relevant parameters such as the model and pixels of the image sensor 4 can be selected according to actual needs. The image acquisition area here refers to the area where the image sensor 4 of the camera can obtain the optical image of this area, and the non-image acquisition area means the area where the optical image of this area cannot be obtained. It should be understood that specifically, the size of the image sensor 4 or its position relative to the camera lens 1 can be changed. For example, an image sensor 4 that is twice as large can be used, and then some functions of the image sensor 4 are blocked, that is, let some of its parts work. In this way, it is also possible to form a horizontal plane centered on the center of the camera lens 1, and one of the upper area and the lower area of the horizontal plane is the image acquisition area, and the other is the non-image acquisition area. Of course, it is also possible to cooperate with or separately implement the layout occlusion of the camera lens 1, etc. The specific composition limitation should be understood that any settings related to the camera lens 1 and the image sensor 4 that can form a horizontal plane centered on the center of the camera lens 1, and one of the upper area and the lower area of the horizontal plane is the image acquisition area, and the other is the non-image acquisition area are included. And it should be understood that the size of the image sensor 4 in this application refers to the size of the area where its image sensor can generate effective light induction, rather than its physical size including structures such as the frame. Further, in order to ensure that the image sensor 4 will not be affected by the camera lens 1 during operation, preferably, the diameter of the image sensor 4 is less than or equal to half of the diameter of the camera lens 1. Of course, this does not constitute a specific limitation, and the radius of the camera lens 1 with its specific size can also be realized.

[0031] Embodiment 2

[0032] Preferably, in order to reduce the modification to the existing camera, the central axis of the image sensor can be parallel to the central axis of the camera lens, and the parallel distance between them is D, and D is not zero. That is to say, the central axis of the traditional image sensor coincides with the central axis of the camera lens, and the image sensor and the camera lens are parallel to each other. As Figure 5As shown in the figure, in a traditional camera, since the central axes of the image sensor 101 and the camera lens 103 coincide, the image acquisition area 103 it generates is an image acquisition area that constructs two symmetric areas above and below the horizontal plane centered on the center of the camera lens. For a projection device, its projection area is upward, that is, only the upper part is projected. If the lower part is projected, it is easily blocked by the desktop or the like. Therefore, the projection device generally projects upward. At this time, if a traditional camera is used, it is obviously troublesome to obtain the image acquisition of its projection area. Therefore, the design of the present application is adopted, as Figure 6 shown. In the figure, the image sensor 201 of the camera is arranged below the central axis of the camera lens 202. The finally formed image acquisition area 203 is on the other side of the camera lens 202, and it is above the horizontal plane constructed by the center of the camera lens 202, while the lower area is a non-image acquisition area. Compared with the traditional one, it is obvious that the image acquisition area 203 of the present application, compared with the traditional image acquisition area 103, the image acquisition area 203 is concentrated in the upper area of the horizontal plane constructed by the center of the camera lens 202, that is, the area with the same light path as the projection area of the projection device. In the present application, the distance between the central axis of the image sensor and the central axis of the camera lens can be specifically designed according to specific requirements. During the design process, it can be determined according to the projection area of the projection device. It should be understood that the design of the image acquisition area 203 of the present application is to make its light path match that of the projection area of the projection device, so that it can completely collect the image of the projection area. After collecting the image of the projection area, relevant processing can be directly performed, reducing unnecessary steps of subsequent processing of the collected image due to incomplete or deviated image acquisition by the camera, as well as reducing or eliminating the higher processor overhead caused by setting the deflection angle of the camera to obtain the image of the entire projection area, and the algorithm will also cause image distortion. At the same time, this method has a higher difficulty in the mold development and processing of the projector due to the rotation of the internal parts.

[0033] Embodiment 3

[0034] Specifically, in the present application, the distance between the central axis of the image sensor and the central axis of the camera lens can be greater than the distance from the center of the image sensor to its side, or less than the distance to its side. Preferably, the distance D is equal to the distance from the center point of the image sensor to one of its sides. For specific examples, such as Figure 7As shown, the lens center 307 is the origin. The horizontal axis 308 and the vertical axis 309 in the plane direction divide it into the first quadrant, the second quadrant, the third quadrant, and the fourth quadrant respectively. The image sensor 306 is disposed in the third quadrant and the fourth quadrant, and the central axis of the image sensor 306 coincides with the vertical axis 309. The PCB module 304 is provided with a module 304 data connector 310 for plugging in an external device and exposed outside the projector. The phase plane size of the camera lens 305 is larger than the size of the image sensor 306 to prevent the phase plane from not completely covering the image sensor 306. The entire image sensor 306 is located below the lens center 307 of the camera lens 305, and its central axis coincides with the vertical axis 309. The chip model of the image sensor 306 is preferably but not limited to OV9732 with 1280x720 pixels, where the chip imaging area is 3888umX2208um. Since the image sensor 306 moves downward relative to the lens center 307 of the camera lens 305, in order to avoid black corners in the captured image, that is, the phase plane of the camera lens 305 cannot completely cover the image sensor 306, a camera lens 305 with a phase plane size of 1 / 2', 6.4x4.8mm is required, and the image capture angle of the camera lens 305 is 58°. In this embodiment, the phase plane size of the camera lens 305 is larger than the size of the image sensor 306, which can ensure that no black corners are generated during the image capture process by the camera. It should be understood that the sizes listed in this embodiment do not constitute specific limitations, and the specific sizes can be matched according to the projection area of the projection device. In this embodiment, since the image sensor 306 is completely disposed below the horizontal axis 308 in the plane direction of the camera lens 305, and the size of the image sensor 306 has not changed at all, which is equivalent to that the size of the image capture area of the image sensor 306 has not changed. In this way, it can be achieved by simply moving the image sensor on the basis of the original camera, which not only reduces the cost, but also has less modification to it and reduces the implementation difficulty. In order to ensure that no black corners are generated during the image capture process by the camera, preferably, the phase plane size of the camera lens 305 is twice the size of the image sensor 306. Of course, it can also be greater than twice or less than twice. The specific image sensor 306 can be specifically set according to the phase plane size of the camera lens 305. Of course, the phase plane size of the camera lens 305 can also be selected according to the size of the image sensor 306. It should be understood that as long as the image sensor 306 and the camera lens 305 can work in a matching manner and no black corners are generated. In order to ensure that the image of the projection area of the projection device can be completely captured, preferably, the angle of the camera lens 305 is 40-80 degrees.It should be understood that the angle of the camera lens here needs to be set to match the horizontal projection angle and vertical projection angle of the optical engine of the projection device. For example, the angle of the camera lens can be 58 degrees. At the same time, the horizontal projection angle of the optical engine of the projection device is 44 degrees, and the vertical projection angle is 23 degrees. Of course, the angle of the camera lens can also be various angle values such as 40 degrees, 45 degrees, 50 degrees, 60 degrees, 65 degrees, 70 degrees, 75 degrees, 80 degrees, etc. The specific angle values do not constitute a limitation.

[0035] Embodiment 4

[0036] Combined with Figure 8 And Figure 9 This embodiment will describe the projection device. The present application provides a projection device 400, which includes an optical engine 5 and a camera. Specifically, the camera can be any camera in the above embodiments of the present application. For the convenience of the camera to better obtain the image of the projection area of the projection device 400 and for aesthetics, preferably, the center of the projection lens 6 of the optical engine 5 and the center of the camera lens 1 of the camera are on the same horizontal plane. As Figure 8 shown, the projection lens 6 and the camera lens 1 of the projection device 400 are on the same horizontal plane at this time. When the projection lens works, the projection area will be projected and displayed upward in a square area with the horizontal plane as the reference. With the camera of the present application, since one of the upper area and the lower area above the horizontal plane forms an image acquisition area and the other is a non-image acquisition area, the upper area can be selected as the image acquisition area at this time. That is to say, the optical path of the image acquisition area of the camera and the projection area of the projection device 400 is the same, both expanding upward in a region with the horizontal plane as the reference. Then, at this time, only by making the center of the projection lens 6 of the optical engine 5 and the center of the camera lens 1 of the camera on the same horizontal plane, the projection area of the projection device and the image acquisition area of the camera can be well coincided, that is, the camera can conveniently perform image acquisition on the projection device. Of course, it is also possible that the center of the projection lens 6 of the optical engine 5 and the center of the camera lens 1 of the camera are not on the same horizontal plane and can be set with a certain deviation. At this time, the acquired image needs to be adjusted to a certain extent, or the image acquisition area of the camera is made larger than the projection area of the projection device to include the projection area. Of course, in order to reduce these processes, preferably, the center of the projection lens 6 of the optical engine 5 and the center of the camera lens 1 of the camera are selected to be on the same horizontal plane.

[0037] Furthermore, as Figure 9As shown, in order to ensure that all the images in the projection area of the projection device are captured by the camera and avoid omission of some images, preferably, the area of the image capture area of the camera is larger than the area of the projection area of the projection lens 6. In order to facilitate users to view the images and obtain a relatively wide-screen projection area, preferably, the horizontal projection angle of the optical engine 5 is 20 - 70 degrees, and the vertical projection angle of the optical engine 5 is 15 - 45 degrees. For specific examples, the horizontal projection angles of the optical engine 5 are 20 degrees, 25 degrees, 30 degrees, 38 degrees, 48 degrees, 56 degrees, 60 degrees, 70 degrees, etc. The specific angles of the horizontal projection angle do not constitute a limitation. The vertical projection angles of the optical engine 5 are 15 degrees, 18 degrees, 20 degrees, 25 degrees, 28 degrees, 32 degrees, 40 degrees, 45 degrees, etc. The specific angles of the vertical projection angle do not constitute a limitation.

[0038] The above is only a preferred embodiment of the present invention, and does not impose any limitation on the technical scope of the present invention. Those skilled in the art can make some deformations and modifications under the inspiration of this technical solution. Any modifications, equivalent changes, and decorations made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A camera for a projection device, characterized in that: It includes a camera lens (1), a lens mount (2) assembled with the camera lens (1), a circuit board (3), and an image sensor (4) connected to the circuit board (3). With respect to the horizontal plane constructed along the central axis of the camera lens, the relative positions of the image sensor (4) and the camera lens (1) are set such that one of the upper and lower regions on the horizontal plane on the imaging surface side of the camera lens (1) is the image acquisition area, and the other is the non-image acquisition area.

2. The camera for a projection device according to claim 1, characterized in that, the central axis L4 of the image sensor (4) is parallel to the central axis L1 of the camera lens (1), and the parallel distance between them is D, and D is not zero.

3. The camera for a projection device according to claim 2, characterized in that: the distance D is equal to the distance from the center point of the image sensor (4) to one of its sides.

4. The camera for a projection device according to claim 1, characterized in that: the phase plane size of the camera lens (1) is larger than the size of the image sensor (4).

5. The camera for a projection device according to claim 4, characterized in that: the phase plane size of the camera lens (1) is twice the size of the image sensor (4).

6. The camera for a projection device according to claim 1, characterized in that: the angle of the camera lens (1) is 40 - 80 degrees.

7. A projection device, characterized in that: it includes an optical engine (5) and a camera according to any one of claims 1 - 5.

8. The projection device according to claim 7, characterized in that, the center of the projection lens (6) of the optical engine (5) and the center of the camera lens (1) of the camera are on the same horizontal plane.

9. The projection device according to claim 8, characterized in that, the area of the image acquisition area of the camera is larger than the area of the projection area of the projection lens (6).

10. The projection device according to claim 7, characterized in that, the horizontal projection angle of the optical engine (5) is 20 - 70 degrees, and the vertical projection angle of the optical engine (5) is 15 - 45 degrees.

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