Imaging device

Abstract

To provide an imaging apparatus capable of moving a lens barrel along an optical axis with compact constitution.SOLUTION: An imaging apparatus 1 comprises a front case 2 where a lens barrel storage part 24 having a female screw part 24A is formed, and a lens barrel 20 which can be attached inside the lens barrel storage part 24. The lens barrel 20 has a lens barrel 23 retaining a lens 22. The imaging apparatus 1 further comprises an imaging element 32 which receives light passed through the lens 23 of the lens barrel 20. The lens barrel 23 includes a male screw part 81 which meshes the female screw part 24A of the lens barrel storage part 24, and a flange part 82 which has an operation part 25 formed at a part of an outer peripheral part. The front case 2 has a cut part 24C formed with the flange part 82, located inside the lens barrel storage part 24, exposed upward.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to an imaging device, and more particularly to an imaging device in which the position of a lens barrel that holds a lens can be moved in the direction of an optical axis. [Background technology]

[0002] In recent years, driver monitoring systems (DMS) that monitor the driver's state (such as signs of decreased attention or drowsiness) have been developed to prevent automobile accidents. As such a DMS, an imaging device that captures an image of the driver while illuminating the driver with light such as near-infrared light is known (see, for example, Patent Document 1). Such imaging devices are often embedded in cosmetic parts such as the dashboard or instrument panel of an automobile, but there is a demand for them to be as compact as possible so as not to affect the design of the vehicle interior.

[0003] In such an imaging device, a male screw formed on a lens barrel that holds a lens is screwed into a female screw formed on a housing, so that the position of the lens barrel can be moved in the optical axis direction, and the focus position can be adjusted. For example, the lens barrel is moved in the optical axis direction by holding the lens barrel with a jig from the outer periphery and rotating the lens barrel. In this case, since the lens barrel needs to be held with a jig from the outer periphery, it is necessary to secure a space around the lens barrel for inserting the jig. For this reason, the dimensions of the housing, especially the height dimension, tend to be large. From this perspective, a technology that can effectively reduce the dimensions of the housing of an imaging device is required. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2019-95541 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in consideration of the problems with the conventional technology, and has an object to provide an imaging device that can move a lens barrel in the optical axis direction with a compact configuration. [Means for solving the problem]

[0006] According to one aspect of the present invention, there is provided an imaging device capable of moving a lens barrel in the optical axis direction with a compact configuration. The imaging device includes a housing in which a barrel housing section having a female thread is formed, and a lens barrel that can be attached inside the barrel housing section of the housing. The lens barrel has at least one lens and a lens barrel that holds the at least one lens. The imaging device further includes an imaging element that receives light that has passed through the at least one lens of the lens barrel. The lens barrel of the lens barrel includes a male thread that screws into the female thread of the barrel housing section of the housing, and a flange portion located in front of the male thread and having an operation portion formed on at least a part of the outer periphery. The housing is formed with a cutout portion that exposes the flange portion located inside the barrel housing section upward. An upper recess is formed on the front edge of the top surface of the housing, and a part of the lens barrel housing portion of the housing and the upper recess communicate with each other through the cutout portion. [Brief description of the drawings]

[0007] [Figure 1] FIG. 1 is a perspective view showing an imaging device according to an embodiment of the present invention. [Diagram 2] FIG. 2 is an exploded perspective view of the imaging device shown in FIG. [Diagram 3] FIG. 3 is a vertical sectional view of the imaging device shown in FIG. [Figure 4] FIG. 4 is a cross-sectional view taken along line AA in FIG. [Diagram 5] FIG. 5 is a schematic diagram showing an example in which the imaging device shown in FIG. 1 is installed in a vehicle interior. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, an embodiment of an imaging device according to the present invention will be described in detail with reference to Figs. 1 to 5. In Figs. 1 to 5, identical or corresponding components are denoted with the same reference numerals, and duplicated explanations will be omitted. In Figs. 1 to 5, the scale or dimensions of each component may be exaggerated or some components may be omitted. In the following description, unless otherwise specified, terms such as "first" and "second" are used only to distinguish components from each other, and do not indicate a specific order or sequence.

[0009] Fig. 1 is a perspective view showing an imaging device 1 in one embodiment of the present invention, and Fig. 2 is an exploded perspective view of the imaging device 1. The imaging device 1 in this embodiment will be described as an imaging device used in a driver monitoring system (DMS) as described above, but it goes without saying that the imaging device according to the present invention can also be used for other purposes.

[0010] As shown in Figs. 1 and 2, the imaging device 1 includes a housing 4 composed of a front case 2 and a rear case 3, and the housing 4 contains, for example, two LEDs (light-emitting diodes) 31 as a light source for emitting near-infrared light, and a lens barrel 20 holding at least one lens 22 therein. In Fig. 1, a cover member 60, which will be described later, is omitted for ease of understanding. In this embodiment, for the sake of convenience, the +Y direction in Fig. 1 is referred to as "front" or "forward", and the -Y direction is referred to as "rear" or "rear". In addition, the +Z direction in Fig. 1 is referred to as "upper" or "upper", and the -Z direction is referred to as "lower" or "lower".

[0011] A circuit board 30 on which an LED 31 and an imaging element 32 are mounted is housed between the front case 2 and rear case 3 of the imaging device 1, and a shielding member 45 for reducing signal noise is disposed inside the rear case 3. The circuit board 30 extends in the X direction (width direction) as a whole, and an LED connector 41 and a camera connector 42 are attached to the rear surface of the circuit board 30. The circuit board 30 and the rear case 3 are fixed to the front case 2 with screws 52.

[0012] The rear case 3 has a cylindrical portion 51 extending rearward (in the -Y direction), and the camera connector 42 is inserted and housed inside the cylindrical portion 51. A mating connector (not shown) can be connected to the camera connector 42 from the rear of the rear case 3, and a signal obtained by the imaging element 32 is output to the outside via the camera connector 42. In addition, the rear end of the LED connector 41 protrudes from the rear case 3 and is exposed to the outside, and a mating connector (not shown) can be connected to the LED connector 41 from the rear of the rear case 3. This allows a control signal to be input to the LED 31 via the LED connector 41.

[0013] As shown in FIG. 2, a recess 11 (upper recess) recessed in the -Z direction is formed at the front edge of the top surface 2A of the front case 2, and a recess 12 (front recess) recessed in the -Y direction is formed at the upper edge of the front surface 2B of the front case 2. A barrel housing section 24 for housing the lens barrel 20 is formed at approximately the center in the width direction of the front recess 12, and window sections (openings) 26 are formed on both sides in the width direction, sandwiching the barrel housing section 24. The barrel housing section 24 has a female screw section 24A inside. Thus, in this embodiment, the barrel housing section 24 and the window section 26 are formed side by side in the width direction in the front recess 12 of the front case 2.

[0014] A cover member 60 is attached to the front of the front case 2, covering the front of the lens barrel housing portion 24 and the window portion 26 of the front case 2. This cover member 60 is attached to the front case 2 with an adhesive, double-sided tape, or the like (not shown). In addition, this cover member 60 is formed from a material that transmits the light emitted from the LED 31. In this embodiment, since near-infrared light is emitted from the LED 31 and an image of near-infrared light is acquired by the image sensor 32, a visible light cut filter that cuts light in the visible light wavelength range can be used as the cover member 60 to reduce the effect of visible light on the image acquired by the image sensor 32.

[0015] Fig. 3 is a vertical cross-sectional view of the imaging device 1. As shown in Fig. 2 and Fig. 3, the cover member 60 has a first cover piece 61 disposed in the upper recess 11 of the front case 2, and a second cover piece 62 disposed in the front recess 12 of the front case 2. The first cover piece 61 extends along the XY plane, and the second cover piece 62 extends along the XZ plane, with the first cover piece 61 and the second cover piece 62 intersecting each other at a right angle.

[0016] 3, the thickness in the Z direction of the first cover piece 61 of the cover member 60 is approximately the same as the depth in the Z direction of the upper recess 11 of the front case 2. The thickness in the Y direction of the second cover piece 62 of the cover member 60 is approximately the same as the depth in the Y direction of the front recess 12 of the front case 2. Therefore, when the cover member 60 is attached to the front case 2, the upper surface 2A of the front case 2 and the surface of the first cover piece 61 are approximately flush with each other. Therefore, the front surface 2B of the front case 2 and the surface of the second cover piece 62 are approximately flush with each other, enhancing the sense of unity of the imaging device 1.

[0017] As shown in Fig. 3, the lens barrel 20 includes one or more lenses 22 and a lens barrel 23 that holds the lenses 22. In the cross-sectional view of Fig. 3, for simplification, the multiple lenses are collectively shown as one lens 22.

[0018] Lens barrel 23 includes a male thread portion 81 that screws into female thread portion 24A of barrel housing portion 24 of front case 2, and a flange portion 82 located in front of male thread portion 81. This flange portion 82 has a larger diameter than male thread portion 81. By screwing male thread portion 81 of lens barrel 20 into female thread portion 24A of barrel housing portion 24 of front case 2, lens barrel 20 is attached to the inside of barrel housing portion 24 of front case 2.

[0019] As shown in FIG. 3, the imaging element 32 is disposed on a surface on which light passing through the lens 22 of the lens barrel 20 forms an image, and is configured to receive light passing through the lens 22. Also, as shown in FIG. 3, the central axis (optical axis) P of the lens barrel 20 is located above the center between the upper surface 2A and the lower surface 2C of the front case 2. That is, the central axis P of the lens barrel 20 is located closer to the upper surface 2A than to the lower surface 2C of the front case 2. When the imaging device 1 is embedded in a cosmetic part such as a dashboard or an instrument panel inside a vehicle, the parts other than the lens barrel 20 can be embedded in the cosmetic part. Therefore, by disposing the lens barrel 20 toward the upper side in the front case 2 in this way, the height at which the imaging device 1 protrudes from the cosmetic part can be reduced. This reduces the impact of the imaging device 1 on the design of the vehicle interior.

[0020] FIG. 4 is a cross-sectional view taken along line AA in FIG. 3, but for ease of understanding, the components other than the lens barrel 20 are shown in cross section. FIG. 3 described above corresponds to the cross-sectional view taken along line BB in FIG. 4. As shown in FIG. 4, an LED 31 mounted on a circuit board 30 is located behind the window 26 of the front case 2. With this configuration, light (illumination light) from the LED 31 can be emitted through the window 26 of the front case 2 to illuminate a subject to be photographed (e.g., a driver). In this way, in this embodiment, imaging can be performed by the imaging element 32 while illumination is performed by the light from the LED 31, so that a higher quality image can be obtained.

[0021] 4, in this embodiment, a part of the cylindrical outer periphery of flange portion 82 of lens barrel 23 is cut out, thereby forming operation portion 25 that can be gripped by a jig (not shown). In addition, a gap G large enough to allow the above-mentioned jig to be inserted is formed between inner circumferential wall 24B of lens barrel housing portion 24 of front case 2 and operation portion 25 of flange portion 82.

[0022] Returning to FIG. 1, the upper recess 11 of the front case 2 is formed with a notch 24C that communicates the lens barrel housing portion 24 and the upper recess 11. The flange portion 82 located inside the lens barrel housing portion 24 is exposed upward through this notch 24C. With this configuration, before the cover member 60 is attached to the front case 2, the upper portion of the flange portion 82 of the lens barrel 20 can be exposed through the notch portion 24C of the front case 2. Therefore, a space for accessing the operation portion 25 can be secured above the flange portion 82, and it becomes easy to rotate the lens barrel 20 by gripping the operation portion 25 with a jig. This allows the lens barrel 20 to be moved in the Y direction (optical axis direction) via the male screw portion 81 of the lens barrel 23 and the female screw portion 24A of the lens barrel housing portion 24 to be screwed together, thereby adjusting the position of the lens barrel 20. By moving the lens barrel 20 in the Y direction in this way, the focus position of the image obtained by the imaging element 32 can be adjusted.

[0023] Furthermore, after adjusting the position of lens barrel 20 in the optical axis direction, first cover piece 61 of cover member 60 is placed in upper recess 11 formed in top surface 2A of front case 2, so that flange portion 82 of lens barrel 20 exposed as described above can be covered with first cover piece 61. Because first cover piece 61 is placed in upper recess 11 formed in top surface 2A of front case 2, an increase in the thickness of housing 4 due to cover member 60 is suppressed, and imaging device 1 can be made compact.

[0024] Furthermore, in this embodiment, because the second cover piece 62 of the cover member 60 is disposed in the front recess 12 of the front case 2, the lens barrel 20 housed in the barrel housing section 24 of the front case 2 is protected by the second cover piece 62 of the cover member 60. Furthermore, because the second cover piece 62 is disposed in the front recess 12 formed in the front surface 2B of the front case 2, an increase in the depth (length in the Y direction) of the housing 4 is suppressed by the cover member 60, and the imaging device 1 can be made compact.

[0025] 4, a relief recess 61A is formed in the portion of the first cover piece 61 of the cover member 60 of this embodiment that faces the flange portion 82 of the lens barrel 20 to avoid interference with the flange portion 82 of the lens barrel 20. By forming such a relief recess 61A, it is possible to avoid interference between the first cover piece 61 and the flange portion 82 of the lens barrel 23 while maintaining the thickness of the other portions of the first cover piece 61. In other words, it is possible to minimize the thickness of the first cover piece 61 while maintaining the strength of the cover member 60, thereby making the imaging device 1 even more compact.

[0026] In this embodiment, the operating portion 25 is formed by cutting out a portion of the outer periphery of the cylindrical flange portion 82, but the operating portion 25 is not limited to this, and a protrusion protruding from the outer periphery of the cylindrical lens barrel 23 can also be used as the operating portion 25.

[0027] In addition, in this embodiment, the cutout portion 24C is formed in the upper recess 11 of the front case 2, but the cutout portion 24C may be formed in the upper surface 2A of the front case 2 without forming the upper recess 11 in the front case 2. In addition, the cover member 60 is not essential.

[0028] The terms "upper", "lower", "upper", "lower", "upper side", "lower side", "front", "forward", "rear", "rear", "width direction", "height direction", and other terms indicating positional relationships used in this specification are only used to specify relative relationships between elements in relation to the illustrated embodiment, and do not specify absolute positional relationships. Therefore, it should be noted that if the position or attitude of the imaging device 1 changes, the directions indicated by these terms also change accordingly. For example, as in the imaging device 1A of FIG. 5, the imaging device 1 described above may be embedded in the dashboard 100 between the driver's seat D and the passenger seat Q of an automobile, and in this case, the above-mentioned "upper" and "upper" mean vertically upward, and the above-mentioned "lower" and "lower" mean vertically downward. Alternatively, as in the imaging device 1B of FIG. 5, the imaging device 1 described above may be embedded in the roof part 102 of an automobile, and in this case, the above-mentioned "upper" and "upper" mean vertically downward, and the above-mentioned "lower" and "lower" mean vertically upward. For example, infrared rays are emitted from the LED 31 of such an imaging device 1 toward the driver's seat D, and the state of the driver is analyzed from the image of the driver captured by the imaging element 32 through the lens 22.

[0029] As described above, according to one aspect of the present invention, there is provided an imaging device capable of moving a lens barrel in the optical axis direction with a compact configuration. The imaging device includes a housing in which a barrel housing section having a female thread is formed, and a lens barrel that can be attached inside the barrel housing section of the housing. The lens barrel has at least one lens and a lens barrel that holds the at least one lens. The imaging device further includes an imaging element that receives light that has passed through the at least one lens of the lens barrel. The lens barrel of the lens barrel includes a male thread that screws into the female thread of the barrel housing section of the housing, and a flange portion that is located in front of the male thread and has an operation portion formed on at least a part of the outer periphery. The housing is formed with a cutout portion that exposes the flange portion located inside the barrel housing section upward.

[0030] According to this imaging device, before the cover member is attached to the housing, the upper part of the flange of the lens barrel can be exposed through the cutout of the housing. Therefore, a space for accessing the operation part can be secured above the flange, and it becomes easy to rotate the lens barrel by gripping the operation part with a jig. This makes it possible to adjust the position of the lens barrel by moving the lens barrel in the optical axis direction via the male thread of the lens barrel and the female thread of the barrel housing part being screwed together.

[0031] An upper recess may be formed on a front edge of the upper surface of the housing. In this case, a part of the lens barrel housing of the housing and the upper recess may be in communication with each other through the cutout. The imaging device may further include a cover member attached to the housing so as to cover the lens barrel housing of the housing, and it is preferable that the cover member has a first cover piece disposed in the upper recess of the housing.

[0032] According to this configuration, after adjusting the position of the lens barrel in the optical axis direction, the first cover piece is placed in the upper recess formed on the top surface of the housing, so that the flange portion of the lens barrel exposed as described above can be covered with the first cover piece. Because this first cover piece is placed in the upper recess formed on the top surface of the housing, an increase in the thickness of the housing due to the cover member is suppressed, and the imaging device can be made compact.

[0033] The first cover piece of the cover member may have a recess formed therein to avoid interference with the flange of the lens barrel of the lens barrel. By forming such a recess, it is possible to avoid interference between the first cover piece and the flange of the lens barrel while maintaining the thickness of the other parts of the first cover piece. In other words, it is possible to minimize the thickness of the first cover piece while maintaining the strength of the cover member, thereby making the imaging device even more compact.

[0034] It is also preferable that a front recess is formed on the upper edge of the front surface of the housing. It is also preferable that the cover member has a second cover piece arranged in the front recess of the housing. In this case, it is possible to protect the lens barrel housed in the barrel housing of the housing by the second cover piece of the cover member. In addition, since the second cover piece is arranged in the front recess formed in the front surface of the housing, an increase in the depth of the housing due to the cover member is suppressed, and the imaging device can be made compact.

[0035] It is preferable that a gap is formed between the inner peripheral wall of the lens barrel housing part of the housing and the operating part of the flange part. In this case, a jig can be inserted into the gap between the inner peripheral wall of the lens barrel housing part and the operating part of the flange part, making it easy to rotate the lens barrel.

[0036] It is preferable that the center axis of the lens barrel is located closer to the top surface of the housing than to the bottom surface of the housing. For example, when the imaging device is embedded in a cosmetic part such as a dashboard or an instrument panel inside a vehicle, the parts other than the lens barrel can be embedded in the cosmetic part, so by locating the lens barrel in the upper part of the housing in this way, the height at which the imaging device protrudes from the cosmetic part can be reduced. Therefore, the impact of the imaging device on the design of the vehicle interior can be reduced.

[0037] The imaging device may further include at least one light source that emits light through a window formed in the housing. According to this configuration, imaging can be performed by the imaging element while illumination is performed by light from the light source, so that a higher quality image can be obtained. In this case, in order to improve the quality of the image obtained by the imaging element, it is preferable that the cover member is configured to suppress transmission of light of a specific wavelength.

[0038] Although the preferred embodiments of the present invention have been described above, it goes without saying that the present invention is not limited to the above-described embodiments and may be embodied in various different forms within the scope of the technical concept thereof. [Explanation of symbols]

[0039] 1. Imaging device 2 Front case 2A Top 2B Front 2C Bottom 3 Rear case 4. Chassis 11 Upper recess 12 Front recess 20 Lens barrel 22 Lens 23 Lens barrel 24 Tube storage section 24A Female thread 24B Inner wall 24C Notch 25 Control section 26 Window section 30 Circuit Board 31 LED (light source) 32 Image sensor 60 Cover member 61 First cover piece 61A Relief recess 62 Second cover piece 81 Male thread 82 Flange G gap

Claims

1. a housing in which a lens barrel housing portion having a female screw portion is formed; A lens barrel that can be attached to the inside of the barrel housing of the housing, At least one lens; a lens barrel for holding the at least one lens; a lens barrel having an image sensor that receives light that has passed through the at least one lens of the lens barrel; Equipped with The lens barrel of the lens barrel includes: a male thread portion that screws into the female thread portion of the lens barrel housing portion of the housing; a flange portion located in front of the male screw portion and having an operating portion formed on at least a part of an outer periphery thereof; Including, a cutout portion is formed in the housing to expose the flange portion located inside the lens barrel housing portion upward, An upper recess is formed on the front edge of the upper surface of the housing, a part of the lens barrel housing portion of the housing and the upper recess portion communicate with each other through the cutout portion; Imaging device.

2. The imaging device according to claim 1 , further comprising a cover member attached to the housing so as to cover the lens barrel housing portion of the housing, the cover member having a first cover piece disposed in the upper recess of the housing.

3. The imaging device according to claim 2 , wherein the first cover piece of the cover member is formed with a recess for avoiding interference with the flange portion of the lens barrel of the lens barrel.

4. A front recess is formed on the upper edge of the front surface of the housing, The cover member has a second cover piece disposed in the front recess of the housing. The imaging device according to claim 2 or 3.

5. The imaging device according to claim 2 , wherein the cover member is configured to suppress transmission of light of a specific wavelength.

6. The imaging device according to claim 1 , wherein a gap is formed between an inner peripheral wall of the lens barrel housing portion of the housing and the operation portion of the flange portion.

7. The imaging device according to claim 1 , wherein a central axis of the lens barrel is located closer to an upper surface of the housing than to a lower surface of the housing.

8. The imaging device according to claim 1 , further comprising at least one light source that emits light through a window portion formed in the housing.

Images