Optical device, and imaging unit equipped with the optical device

Abstract

The present disclosure provides: an optical device that can remove foreign matter attached to a translucent body covering the outside, and improve the image quality of an image obtained by an imaging element; and an imaging unit provided with said optical device. The optical device (100) of the present disclosure comprises an outermost layer lens (1) (translucent body), a housing (2), a vibrator (3), an inner layer lens (4) (first lens), a fixing part (5), and a position adjustment part (6). The vibrator (3) vibrates the outermost layer lens (1) held in the housing (2). The inner layer lens (4) is provided at a position facing the outermost layer lens (1) inside the housing (2). The fixing part (5) fixes the inner layer lens (4) to the housing (2). The position adjustment part (6) is provided to the fixing part (5) and adjusts an alignment of the inner layer lens (4) relative to the outermost layer lens (1). The fixing part (5) is connected to a section, of the housing (2), serving as a node of vibration by the vibrator (3).

Description

Technical Field

[0001] The present disclosure relates to an optical device and an imaging unit including the optical device.

Background Art

[0002] An imaging unit is provided at the front or rear of a vehicle, and the image obtained by the imaging unit is used to control a safety device or perform driving support control. Since such an imaging unit is often provided outside the vehicle, foreign substances such as raindrops (water droplets), mud, and dust may adhere to a light-transmitting body (protective cover or lens) that covers the outside. When foreign substances adhere to the light-transmitting body, the foreign substances are reflected in the image obtained by the imaging unit, and a clear image cannot be obtained.

[0003] Therefore, in the imaging unit described in Japanese Patent Application Laid-Open No. 2017-170303 (Patent Document 1) or U.S. Patent No. 10401618 (Patent Document 2), a vibrator that vibrates the light-transmitting body is provided to remove foreign substances adhering to the surface of the light-transmitting body.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] The imaging units described in Patent Documents 1 and 2 consist of an image sensor and an optical device including a light-transmitting body and a lens provided in the field of view direction of the image sensor. The optical device requires alignment adjustment between the light-transmitting body and the lens so that light taken in from the light-transmitting body passes through the lens and forms an image on the image sensor. However, the imaging unit described in Patent Document 1 does not have a configuration for aligning the light-transmitting body and the lens, and there was a risk that the image quality obtained from the image sensor would deteriorate.

[0006] Therefore, the purpose of this disclosure is to provide an optical device that can remove foreign matter adhering to a transparent material covering the outside, and can improve the image quality obtained by the image sensor, and an imaging unit equipped with the optical device. [Means for solving the problem]

[0007] An optical device according to one embodiment of the present disclosure comprises a light-transmitting body, a housing, a vibrating body, a first lens, a fixing part, and a position adjustment part. The light-transmitting body transmits light of a predetermined wavelength. The housing holds the light-transmitting body. The vibrating body vibrates the light-transmitting body held in the housing. The first lens is provided in the housing at a position opposite to the light-transmitting body. The fixing part fixes the first lens to the housing. The position adjustment part is provided in the fixing part and adjusts the alignment of the first lens with respect to the light-transmitting body. The fixing part is On the inner wall surface of the housing parallel to the optical axis of the translucent material The nodes of vibration caused by the vibrating body part Connect to minutes This secures the first lens to the housing. .

[0008] An imaging unit according to one embodiment of the present disclosure comprises the optical device described above and an image sensor arranged such that the light-transmitting material is in the field of view direction. [Effects of the Invention]

[0009] According to this disclosure, the optical device and the imaging unit equipped with the optical device adjust the alignment of the first lens with respect to the light-transmitting body using a position adjustment unit provided in the fixed part, thereby enabling the removal of foreign matter adhering to the light-transmitting body covering the outside and improving the image quality obtained by the image sensor. [Brief explanation of the drawing]

[0010] [Figure 1] This is a cross-sectional view of the optical device according to Embodiment 1. [Figure 2] This is a schematic diagram illustrating the vibration modes of the optical device according to Embodiment 1. [Figure 3] This is a semi-cross-sectional view illustrating the position adjustment section of the optical device according to Embodiment 1. [Figure 4] This is a schematic diagram illustrating the alignment adjustment method in the position adjustment section of the optical device according to Embodiment 1. [Figure 5] This is a schematic diagram illustrating the method for fixing the position adjustment unit of the optical device according to Embodiment 1. [Figure 6] This is a cross-sectional view of an imaging unit equipped with an optical device according to Embodiment 1. [Figure 7] This is a semi-cross-sectional view of the optical device according to Embodiment 2. [Figure 8] This is a schematic diagram illustrating the adjustment method in the position adjustment section of the optical device according to Embodiment 2. [Figure 9] This is a schematic diagram illustrating another adjustment method in the position adjustment section of the optical device according to Embodiment 2. [Figure 10] This diagram illustrates a configuration in which the outermost and innermost lenses are held together during the alignment process of an optical device. [Figure 11] This diagram illustrates a configuration that utilizes the outermost and innermost lenses in optical alignment. [Figure 12] This diagram illustrates a configuration in which a vibrating element and an inner lens holder are used for alignment in an optical device. [Figure 13] This diagram illustrates a configuration that utilizes a vibrator and an inner lens for alignment in an optical device. [Figure 14] This is a semi-cross-sectional view of the optical device according to Embodiment 3. [Figure 15] This is a semi-cross-sectional view of an optical device according to a modified example 1 of Embodiment 3. [Figure 16] It is a half cross-sectional view of an optical device according to Modification 2 of Embodiment 3. [Figure 17] It is a schematic view of an inner layer lens and a fixing part according to Modification 2. [Figure 18] It is a half cross-sectional view of an optical device according to Embodiment 4.

Embodiments for Carrying Out the Invention

[0011] Hereinafter, an optical device according to an embodiment and an imaging unit including the optical device will be described in detail with reference to the drawings. In the drawings, the same reference numerals denote the same or corresponding parts. The optical device described below is applied to, for example, an in-vehicle imaging unit, and can vibrate a light-transmitting body (for example, the outermost layer lens) in order to remove foreign matter adhering to the surface of the light-transmitting body. The optical device is not limited to the use of an in-vehicle imaging unit. For example, the optical device can also be applied to a surveillance camera for security, an imaging unit for a drone, and the like.

[0012] (Embodiment 1) FIG. 1 is a cross-sectional view of an optical device 100 according to Embodiment 1. In the figure, the X and Z directions indicate the lateral direction and the height direction of the optical device 100, respectively. The optical device 100 includes an outermost layer lens 1, a housing 2, a vibrating body 3, an inner layer lens 4, a fixing part 5, and a position adjusting part 6.

[0013] The outermost layer lens 1 is a light-transmitting body that transmits light of a predetermined wavelength (for example, the wavelength of visible light, the wavelength that can be imaged by an imaging element, etc.), and is, for example, a convex meniscus lens. Note that the optical device 100 may use a transparent member such as a protective cover instead of the outermost layer lens 1. The protective cover is made of a resin such as glass or transparent plastics.

[0014] The end of the outermost layer lens 1 is held by the end of the housing 2. The optical device 100 has a vibrating body 3 provided at a position in contact with the outermost layer lens 1 in order to vibrate the outermost layer lens 1 held by the housing 2 3.

[0015] The vibrating body 3 has a cylindrical shape, with an inner lens 4 positioned inside the cylinder. The vibrating body 3 has a connecting portion 31 that connects to the outermost lens 1 (transparent material) and a vibrating portion 32 on which a piezoelectric element 7 is provided. The connecting portion 31 is the part that converts the vibration of the piezoelectric element 7 and has a crank shape. On the other hand, the vibrating portion 32 is the part that vibrates together with the vibration of the piezoelectric element 7 and is thicker than the thin connecting portion 31. The connecting portion 31 and the vibrating portion 32 may be formed as a single unit or individually. The piezoelectric element 7 is provided on the surface of the vibrating body 3 opposite to the side that contacts the outermost lens 1. The piezoelectric element 7 is hollow and circular and vibrates, for example, by polarization in the thickness direction. The piezoelectric element 7 is made of lead zirconate titanate piezoelectric ceramic. However, other piezoelectric ceramics such as (K,Na)NbO3 may be used. Furthermore, piezoelectric single crystals such as LiTaO3 may be used.

[0016] The hollow circular piezoelectric element 7 vibrates radially, and this vibration is converted into vibration in the Z direction (up and down direction in the figure) at the connection part 31 of the vibrating body 3, causing the outermost lens 1 to vibrate in the Z direction. Figure 2 is a schematic diagram illustrating the vibration modes of the optical device 100 according to Embodiment 1. As can be seen from Figure 2, the housing 2 has a part (connection part 31) that holds the outermost lens 1 that elastically deforms like a leaf spring, transmitting the vibration of the vibrating body 3 to the outermost lens 1, and the part away from the outermost lens 1 becomes a vibration node. Here, a vibration node is a part where the amplitude is approximately 1 / 50th or less of the maximum amplitude of the vibrating body 3. Therefore, the displacement is greatest at the center of the outermost lens 1 due to the vibration of the vibrating body 3, while the displacement is smaller at the part away from the outermost lens 1. In Figure 2, the magnitude of the displacement is indicated by the density of the hatching, with darker hatching indicating areas of large displacement, and the displacement is large at the center of the outermost lens 1.

[0017] The optical device 100 is designed so that the vibrations of the vibrator 3 are not transmitted to the inner lens 4 by fixing the inner lens 4 to the housing 2 via a fixing part 5, specifically near the lower end opposite to the upper end that holds the outermost lens 1 of the housing 2, which is a node in the vibration. Therefore, in an imaging unit using the optical device 100, image quality degradation does not occur due to the vibrations of the vibrator 3. Furthermore, by fixing the inner lens 4 to the node in the housing 2, the inner lens 4 does not dampen the vibrations of the vibrator 3, and its performance in removing foreign matter attached to the outermost lens 1 is not reduced.

[0018] The fixing part 5 that secures the inner lens 4 to the housing 2 preferably has a smaller mechanical quality factor Qm than the housing 2. By making the mechanical quality factor Qm of the fixing part 5 smaller than that of the housing 2, it becomes more difficult for vibrations from the vibrating body 3 to be transmitted through the inner lens 4 via the fixing part 5. Specifically, the fixing part 5 is preferably made of resin.

[0019] The inner layer lens 4 has a structure in which multiple lenses are held by an inner layer lens barrel 4a. The inner layer lens barrel 4a is the holding part of the inner layer lens 4. Since the multiple lenses constituting the inner layer lens 4 are held by the inner layer lens barrel 4a in an alignment-adjusted state, it is not necessary to re-adjust the alignment of each lens when mounting it in the optical device 100. However, if alignment adjustment is not performed between the outermost layer lens 1 and the inner layer lens 4 when mounting them in the optical device 100, the image quality obtained from the image sensor may deteriorate. Even if the outermost layer lens 1 is not a lens but a transparent material such as a protective cover, the optical properties of the transparent material, such as the refraction of light transmitted through the transparent material, will affect the image obtained from the image sensor, so alignment adjustment between the transparent material and the inner layer lens 4 will be necessary.

[0020] Therefore, the optical device 100 is provided with a position adjustment unit 6 between the fixing unit 5 and the housing 2 for adjusting the alignment of the outermost lens 1 and the inner lens 4. Figure 3 is a semi-cross-sectional view illustrating the position adjustment unit 6 of the optical device 100 according to Embodiment 1. The dashed line shown in Figure 3 represents the portion passing through the central axis of the optical device 100.

[0021] As shown in Figure 3 Ta The position adjustment unit 6 has a screw groove 6a provided on the inner wall surface of the housing 2, and two ring-shaped screws 6b and 6c corresponding to this screw groove 6a. The position adjustment unit 6 can fix the position of the inner layer lens 4 relative to the housing 2 by clamping the end of the fixing unit 5 with the two ring-shaped screws 6b and 6c. Then, by rotating the two ring-shaped screws 6b and 6c in the direction of arrow A, the two ring-shaped screws 6b and 6c move along the screw groove 6a, and the fixing unit 5 can be moved in the Z direction. Therefore, the position adjustment unit 6 can adjust the focal position by moving the inner layer lens 4 in the direction of arrow B (Z direction) relative to the outermost layer lens 1. Since this position adjustment unit 6 is provided in the part of the housing 2 where vibration by the vibrator 3 is suppressed, the position adjustment unit 6 This can suppress damage and displacement caused by vibration.

[0022] Alignment adjustment between the outermost lens 1 and the innermost lens 4 involves not only adjusting the focal position by moving the innermost lens 4 in the Z direction relative to the outermost lens 1, but also adjusting the optical axis by aligning the optical axis of the outermost lens 1 with the optical axis of the innermost lens 4. This alignment adjustment method, including the optical axis adjustment, will be explained using diagrams. Figure 4 is a schematic diagram illustrating the alignment adjustment method at the position adjustment unit 6 of the optical device 100 according to Embodiment 1.

[0023] First, as shown in Figure 4(a), the position of the inner lens 4 in the Z direction is determined by fitting the ring-shaped screw 6b into the screw groove 6a and rotating it. Next, the angle θ (elevation angle) between the optical axis of the inner lens 4 and the optical axis of the outermost lens 1 can be adjusted by touching the end of the fixing part 5 fixed to the inner lens 4 against the positioned ring-shaped screw 6b.

[0024] Furthermore, as shown in Figure 4(b), by moving the inner lens 4 and the fixing part 5 in the X and Y directions while the end of the fixing part 5 is in contact with the ring-shaped screw 6b, the optical axis of the inner lens 4 is aligned with the optical axis of the outermost lens 1, and the optical axis adjustment is completed.

[0025] Next, as shown in Figure 4(c), the ring-shaped screw 6c is fitted into the screw groove 6a and rotated, and the end of the fixing part 5 is clamped between the two ring-shaped screws 6b and 6c to fix the position of the inner layer lens 4 relative to the housing 2. In Figure 4(c), the position of the inner layer lens 4 relative to the housing 2 is fixed by clamping the end of the fixing part 5 between the two ring-shaped screws 6b and 6c, but the fixing method is not limited to this method.

[0026] Figure 5 is a schematic diagram illustrating the method for fixing the position adjustment section 6 of the optical device 100 according to Embodiment 1. In Figure 5(a), instead of a ring-shaped screw 6c, a metal or resin plate 6d that can be crimped is fitted into the screw groove 6a, and the end of the fixing section 5 is fixed by sandwiching it between the crimped plate 6d and the ring-shaped screw 6b. The state of the plate 6d after crimping is shown by a dashed line.

[0027] In Figure 5(b), instead of the ring-shaped screw 6c, the end of the fixing part 5 is sandwiched between a block 6e fitted into the screw groove 6a and a ring-shaped screw 6b, and then fixed with adhesive. Of course, the end of the fixing part 5 may also be fixed to the ring-shaped screw 6b with adhesive alone without using the block 6e.

[0028] In Figures 4 and 5, the position of the inner lens 4 in the Z direction is adjusted using a ring-shaped screw 6b, but the screw portion may also be directly provided at the end of the fixing portion 5. The position adjustment portion 6 has a screw portion at the end of the fixing portion 5 and adjusts the alignment of the inner lens 4 with respect to the outermost lens 1 by changing its position relative to the housing 2 which has a screw groove 6a (groove portion) corresponding to the screw portion. As a result, the position adjustment portion 6 can adjust the position of the inner lens 4 in the Z direction without providing a ring-shaped screw 6b.

[0029] After aligning the outermost lens 1 and the innermost lens 4, the case 10 containing the image sensor 8 is attached to the optical device 100 to form the imaging unit 200. Figure 6 is a cross-sectional view of the imaging unit 200 equipped with the optical device 100 according to Embodiment 1.

[0030] The imaging unit 200 includes an optical device 100 and an image sensor 8 arranged so that the outermost lens 1 and the inner lens 4 face the field of view. The image sensor 8 is an image sensor such as a CCD (Charge Coupled Device) or a CMOS (Complementary Metal-Oxide-Semiconductor) sensor, and is mounted on a circuit board 9. After adjusting the alignment of the image sensor 8 mounted on the circuit board 9 and the inner lens 4, the circuit board 9 is fixed to the fixing part 5 with adhesive. Finally, the imaging unit 200 is completed by joining the case 10 and the housing 2 and fixing them with screws or adhesive.

[0031] As described above, the optical device 100 according to Embodiment 1 comprises an outermost lens 1 (transparent material), a housing 2, a vibrating body 3, an inner lens 4 (first lens), a fixing part 5, and a position adjustment part 6. The outermost lens 1 transmits light of a predetermined wavelength. The housing 2 holds the outermost lens 1. The vibrating body 3 vibrates the outermost lens 1 held in the housing 2. The inner lens 4 is provided in the housing 2 at a position opposite to the outermost lens 1. The fixing part 5 fixes the inner lens 4 to the housing 2. The position adjustment part 6 is provided on the fixing part 5 and adjusts the alignment of the inner lens 4 with respect to the outermost lens 1. The fixing part 5 is connected to the portion of the housing 2 that becomes a node of the vibration by the vibrating body 3.

[0032] As a result, the optical device 100 according to Embodiment 1 has a position adjustment part provided on the fixed part 5 which is connected to the part of the housing 2 that becomes a node of vibration by the vibrating body 3. 6 By adjusting the alignment of the inner lens 4 with respect to the outermost lens 1, foreign matter adhering to the outermost lens 1 covering the exterior can be removed, and the image quality obtained by the image sensor 8 can be improved.

[0033] The light-transmitting material is preferably the outermost lens 1 (second lens). Of course, it may also be a protective cover that is not a lens. The vibrating body 3 is preferably provided with a piezoelectric element 7 on at least one surface. In Figure 1, a hollow circular piezoelectric element 7 is provided on the bottom surface of the vibrating body 3, but piezoelectric elements may also be provided on other surfaces, or multiple rectangular piezoelectric elements 7 may be provided concentrically on the bottom surface of the vibrating body 3.

[0034] The fixed part 5 preferably has a smaller mechanical quality factor Qm than the housing 2. Furthermore, the fixed part 5 is preferably made of resin. This makes it more difficult for vibrations from the vibrating body 3 to be transmitted through the inner lens 4 via the fixed part 5.

[0035] The position adjustment section 6 is preferably provided at the end of the fixing section 5 that is connected to the housing 2. In Figure 1, two ring-shaped screws 6b and 6c that sandwich the end of the fixing section 5 constitute the position adjustment section 6. Since the fixing section 5 is connected to the part of the housing 2 that is a node of vibration caused by the vibrating body 3, providing the position adjustment section 6 at the end of the fixing section 5 allows for highly accurate alignment adjustment without being affected by vibrations from the vibrating body 3, thereby improving the image quality obtained by the image sensor 8.

[0036] The imaging unit 200 comprises an optical device 100 and an image sensor 8 arranged such that the outermost lens 1 and the innermost lens 4 are in the field of view direction. This allows the imaging unit 200 to perform highly accurate alignment adjustments in the optical device 100, thereby improving the image quality obtained by the image sensor 8.

[0037] (Embodiment 2) In the optical device 100 according to Embodiment 1, a configuration was described in which the position adjustment unit 6 is provided at the end of the fixed part 5 connected to the housing 2. However, if the position adjustment unit is provided at the fixed part connected to the part of the housing that is a node of vibration caused by the vibrating body, it will be less affected by vibration caused by the vibrating body. Therefore, in the optical device according to Embodiment 2, a configuration will be described in which the position adjustment unit is provided at the end of the fixed part connected to the inner layer lens (first lens).

[0038] Figure 7 is a semi-cross-sectional view of the optical device 100a according to Embodiment 2. In the optical device 100a shown in Figure 7, components similar to those in the optical device 100 according to Embodiment 1 are denoted by the same reference numerals, and their descriptions are not repeated.

[0039] In the optical device 100a according to Embodiment 2, as shown in Figure 7, the position adjustment unit 6 is a screw portion 6f provided at the end of the fixing portion 5 connected to the inner layer lens 4. A groove corresponding to the screw portion 6f is provided on the inner layer lens barrel 4a. By rotating the inner layer lens barrel 4a in the direction of arrow A, the position adjustment unit 6 moves the inner layer lens barrel 4a along the screw portion 6f, and the inner layer lens 4 can be moved in the Z direction. Therefore, the position adjustment unit 6 can adjust the focal position by moving the inner layer lens 4 in the direction of arrow B (Z direction) relative to the outermost layer lens 1.

[0040] The alignment adjustment method for the optical device 100a according to Embodiment 2 will be explained with reference to the figures. Figure 8 is a schematic diagram illustrating the alignment adjustment method for the position adjustment unit 6 of the optical device 100a according to Embodiment 2.

[0041] First, as shown in Figure 8(a), with the fixing part 5 not fixed to the housing 2, the angle θ (elevation angle) between the optical axis of the inner lens 4 and the optical axis of the outermost lens 1 can be adjusted by touching the flat surface of the inner lens barrel 4a and the flat surface of the outermost lens 1. Furthermore, by moving the inner lens 4 and the fixing part 5 in the X and Y directions while the flat surface of the inner lens barrel 4a is in contact with the flat surface of the outermost lens 1, the optical axis of the inner lens 4 is aligned with the optical axis of the outermost lens 1, and the optical axis adjustment is completed.

[0042] Next, as shown in Figure 8(b), the end of the fixing part 5 is fixed to the housing 2 with adhesive at the position of the inner layer lens 4, which has been aligned with the outermost layer lens 1. In Figure 8(b), the position of the inner layer lens 4 is fixed to the housing 2 by fixing the end of the fixing part 5 to the housing 2 with adhesive, but the fixing method is not limited to this method.

[0043] Furthermore, as shown in Figure 8(c), the position of the inner lens 4 in the Z direction is determined by rotating the inner lens barrel 4a in the direction of arrow A relative to the screw portion 6f. After adjusting the alignment between the outermost lens 1 and the inner lens 4, the imaging unit 200 is formed by attaching the case 10 containing the image sensor 8 shown in Figure 6 to the optical device 100a.

[0044] Next, another alignment adjustment method for the optical device 100a according to Embodiment 2 will be explained with reference to a diagram. Figure 9 is a schematic diagram illustrating another adjustment method for the position adjustment unit 6 of the optical device 100a according to Embodiment 2.

[0045] First, as shown in Figure 9(a), the housing 2 is provided with a projection 6h for joining with the fixing part 5. This projection 6h is used to adjust the angle θ (elevation angle) between the optical axis of the inner lens 4 and the optical axis of the outermost lens 1 by trial and error. In other words, even when the fixing part 5 is not fixed to the housing 2, the angle θ (elevation angle) between the optical axis of the inner lens 4 and the optical axis of the outermost lens 1 can be adjusted by trial and error by bringing the end of the fixing part 5 into contact with the projection 6h.

[0046] Furthermore, as shown in Figure 9(b), the inner lens barrel 4a is rotated in the direction of arrow A relative to the screw portion 6f so that the tapered portion of the inner lens barrel 4a contacts the tapered portion of the vibrating body 3, bringing the inner lens barrel 4a closer to the vibrating body 3. By bringing the tapered portion of the inner lens barrel 4a into contact with the tapered portion of the vibrating body 3, the inner lens 4 and the fixing portion 5 are moved in the X and Y directions, and the optical axis of the inner lens 4 is aligned with the optical axis of the outermost lens 1, completing the optical axis adjustment.

[0047] Furthermore, as shown in Figure 9(c), after the optical axis adjustment is completed to align the optical axis of the outermost lens 1 with the optical axis of the inner lens 4, the position of the inner lens 4 is fixed by sandwiching the end of the fixing part 5 with the projection 6h of the block 6i. The method of fixing the position of the inner lens 4 is not limited to the block 6i; it may also be fixed with a plate that can be crimped or simply with adhesive.

[0048] Next, as shown in Figure 9(d), the position of the inner lens 4 in the Z direction is determined by rotating the inner lens barrel 4a in the direction of arrow A relative to the screw portion 6f. This allows the position adjustment unit 6 to adjust the focal position by moving the inner lens 4 in the Z direction relative to the outermost lens 1.

[0049] Figures 8 and 9 show that alignment adjustment is performed by aligning the flat portion of the inner lens barrel 4a with the flat portion of the outermost lens 1, or by aligning the tapered portion of the inner lens barrel 4a with the tapered portion of the vibrating body 3. Here, the configurations that can be used for aligning are summarized below.

[0050] First, Figure 10 is a diagram illustrating a configuration in which the outermost lens 1 and the inner lens 4's holding portion (inner lens barrel 4a) are used for alignment in an optical device. Figure 10(a) shows that by bringing the flat surface of the outermost lens 1 into contact with the flat surface 4b of the inner lens barrel 4a, the alignment adjustment (mainly the angle θ (elevation angle)) of the inner lens 4 relative to the outermost lens 1 can be performed by alignment.

[0051] Figure 10(b) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the tapered portion of the outermost lens 1 with the tapered portion 4c of the inner lens barrel 4a. Figure 10(c) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the recessed portion 1a of the outermost lens 1 with the convex portion 4d of the inner lens barrel 4a. Note that the shapes formed on the outermost lens 1 and the inner lens barrel 4a are not limited to the recessed portion 1a and the convex portion 4d, and may be reversed.

[0052] Next, Figure 11 is a diagram illustrating a configuration in which the outermost lens 1 and the inner lens 4 are used for alignment in an optical device. Figure 11(a) shows that by bringing the flat surface of the outermost lens 1 and the flat surface 4e of the inner lens 4 into contact, the alignment adjustment (mainly the angle θ (elevation angle)) of the inner lens 4 relative to the outermost lens 1 can be performed by alignment.

[0053] Figure 11(b) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the tapered portion of the outermost lens 1 with the tapered portion of the inner lens 4. Figure 11(c) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the recessed portion 1a of the outermost lens 1 with the convex portion 4f of the inner lens 4. Note that the shapes formed on the outermost lens 1 and the inner lens 4 are not limited to the recessed portion 1a and the convex portion 4f, and may be reversed.

[0054] Next, Figure 12 is a diagram illustrating a configuration in which the vibrating body 3 and the inner lens 4 holding part (inner lens barrel 4a) are used for alignment in an optical device. Figure 12(a) shows that by bringing the flat surface of the vibrating body 3 and the flat surface 4b of the inner lens barrel 4a into contact, the alignment adjustment (mainly the angle θ (elevation angle)) of the inner lens 4 with respect to the outermost lens 1 can be performed by alignment.

[0055] Figure 12(b) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the tapered portion of the vibrating body 3 with the tapered portion 4c of the inner lens barrel 4a. Figure 12(c) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the concave portion 3a of the vibrating body 3 with the convex portion 4d of the inner lens barrel 4a. Note that the shapes formed on the vibrating body 3 and the inner lens barrel 4a are not limited to the concave portion 3a and the convex portion 4d, and may be reversed.

[0056] Finally, Figure 13 illustrates a configuration in which the vibrator 3 and the inner lens 4 are used for alignment in an optical device. Figure 13(a) shows that the alignment adjustment (mainly the angle θ (elevation angle)) of the inner lens 4 relative to the outermost lens 1 can be performed by bringing the flat surface of the vibrator 3 and the flat surface 4e of the inner lens 4 into contact.

[0057] Figure 13(b) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the tapered portion of the vibrating body 3 with the tapered portion of the inner lens 4. Figure 13(c) shows that the alignment of the inner lens 4 relative to the outermost lens 1 (mainly in the X and Y directions) can be adjusted by fitting the concave portion 3a of the vibrating body 3 with the convex portion 4f of the inner lens 4. Note that the shapes formed on the vibrating body 3 and the inner lens 4 are not limited to the concave portion 3a and the convex portion 4f, and may be reversed.

[0058] The alignment configuration described in Figures 10 to 12 can be used not only for the optical device 100a according to Embodiment 2, but also for optical devices according to other embodiments.

[0059] As described above, in the optical device 100a according to Embodiment 2, the position adjustment unit 6 is provided at the end of the fixing unit 5 connected to the inner layer lens 4. The position adjustment unit 6 has a screw portion 6f at the end of the fixing unit 5 and changes its position relative to the inner layer lens barrel 4a, which has a groove portion corresponding to the screw portion 6f, relative to the outermost layer lens 1. Inner lens 4 The alignment is adjusted. As a result, the optical device 100a according to Embodiment 2 has a position adjustment part provided on the fixed part 5 that is connected to the part of the housing 2 that is a node of vibration by the vibrating body 3. 6 This adjusts the alignment of the inner lens 4 with respect to the outermost lens 1, thereby removing foreign matter adhering to the outermost lens 1 that covers the outside, and improving the image quality obtained by the image sensor. The threaded portion 6f at the end of the fixing portion 5 provided in Embodiment 2 may also be provided in the optical device according to other embodiments.

[0060] Preferably, the outermost lens 1 or vibrator 3 has a flat portion (first flat portion), and the inner lens 4 or inner lens barrel 4a has flat portions 4e, 4b (second flat portions), and the flat portion (first flat portion) and the flat portions 4e, 4b (second flat portions) can come into contact with each other. Preferably, the outermost lens 1 or vibrator 3 has a tapered portion (first tapered portion), and the inner lens 4 or inner lens barrel 4a has a tapered portion 4c (second tapered portion), and the tapered portion (first tapered portion) and the tapered portion 4c (second tapered portion) can come into contact with each other. Preferably, the outermost lens 1 or vibrator 3 has recesses 1a, 3a (first fitting portion), and the inner lens 4 or inner lens barrel 4a has protrusions 4f, 4d (second fitting portion), and the recesses 1a, 3a (first fitting portion) and the protrusions 4f, 4d (second fitting portion) are able to be fitted together. This allows the alignment adjustment of the inner lens 4 relative to the outermost lens 1 to be performed by trial and error.

[0061] (Embodiment 3) In Embodiment 1, it was explained that after alignment adjustment, the end of the fixing part 5 may be fixed to the housing 2 with adhesive. In Embodiment 3, a configuration in which the end of the fixing part 5 is fixed to the housing 2 with adhesive after alignment adjustment will be described. Figure 14 is a half cross-sectional view of the optical device 100b according to Embodiment 3. In the optical device 100b shown in Figure 14, the same reference numerals are used for components similar to those in the optical device 100 according to Embodiment 1, and their descriptions will not be repeated.

[0062] As shown in Figure 14, the optical device 100b has a projection 6h on the housing 2 for joining with the fixing part 5. The projection 6h and the end of the fixing part 5 are bonded together with an ultraviolet-curing adhesive 6k. However, in order to cure the adhesive 6k, it is necessary to irradiate it with ultraviolet (UV) light after bonding the projection 6h and the end of the fixing part 5 together. However, if the projection 6h and the fixing part 5 are made of a material that does not transmit ultraviolet light, there is a risk that the adhesive 6k between the projection 6h and the end of the fixing part 5 will not cure even if ultraviolet light is irradiated after bonding the projection 6h and the end of the fixing part 5 together.

[0063] Therefore, the optical device 100b has a member 6j that transmits ultraviolet light at the end of the fixing part 5. By transmitting ultraviolet light, the member 6j allows the ultraviolet-curable adhesive 6k, which is provided between the member 6j and the projection 6h located opposite it, to be cured after adjusting the alignment of the inner lens 4 with respect to the outermost lens 1. Note that not only the end of the fixing part 5, but the fixing part 5 itself may be the member 6j that transmits ultraviolet light.

[0064] In the optical device 100b shown in Figure 14, a member 6j that transmits ultraviolet light is provided at the end of the fixed part 5, but a configuration in which at least one window portion that transmits ultraviolet light is provided at the end of the fixed part 5 is also acceptable. Figure 15 is a half cross-sectional view of the optical device 100c according to modification 1 of Embodiment 3. In the optical device 100c shown in Figure 15, the same reference numerals are used for components similar to those in the optical device 100 according to Embodiment 1, and their descriptions are not repeated.

[0065] The optical device 100c has at least one window portion 6m that transmits ultraviolet light at the end of the fixed portion 5. By transmitting ultraviolet light through the window portion 6m, the ultraviolet-curable adhesive 6k provided between the window portion 6m and the projection portion 6h located opposite it can be cured after adjusting the alignment of the inner lens 4 with respect to the outermost lens 1.

[0066] Furthermore, instead of providing an ultraviolet-transmitting member 6j or window portion 6m at the end of the fixing portion 5, a slit may be provided instead. Figure 16 is a half-cross-sectional view of the optical device 100d according to Modification 2 of Embodiment 3. Figure 17 is a schematic diagram of the inner lens 4 and fixing portion 5 according to Modification 2. In the optical device 100d shown in Figures 16 and 17, the same reference numerals are used for components similar to those in the optical device 100 according to Embodiment 1, and their descriptions will not be repeated.

[0067] The optical device 100d has at least one slit 6n at the end of the fixed part 5. Multiple slits 6n are provided so as to surround the outer circumference of the fixed part 5, as shown in Figure 17. By transmitting ultraviolet light through the slits 6n, the ultraviolet-curable adhesive 6k provided between the slit 6n and the projection 6h located opposite the slit 6n can be cured after adjusting the alignment of the inner lens 4 with respect to the outermost lens 1.

[0068] As described above, in the optical devices 100b and 100c according to Embodiment 3, the fixing part 5 has a member 6j that transmits ultraviolet light or at least one window portion 6m at its end, and by transmitting ultraviolet light, the member 6j or window portion 6m allows the ultraviolet-curing adhesive 6k provided between the member 6j or window portion 6m and the projection 6h located opposite to it to be cured after the alignment of the inner lens 4 with respect to the outermost lens 1 has been adjusted. As a result, in the optical devices 100b and 100c, the fixing part 5 can be fixed to the housing 2 at the position of the end portion after alignment adjustment.

[0069] In the optical device 100d according to Embodiment 3, the fixing part 5 has at least one slit 6n at its end, and by transmitting ultraviolet light through the slit 6n, the ultraviolet-curing adhesive 6k provided between the slit 6n and the projection 6h located opposite the slit 6n can be cured after adjusting the alignment of the inner lens 4 with respect to the outermost lens 1. As a result, the optical device 100d can be fixed to the housing 2 at the position of the end of the fixing part 5 after the alignment adjustment.

[0070] (Embodiment 4) In Embodiment 1, it was explained that the end of the fixing part 5 is fixed after alignment adjustment. In Embodiment 4, a configuration that actively adjusts the alignment in response to alignment fluctuations is adopted as the position adjustment part. Figure 18 is a half cross-sectional view of the optical device according to Embodiment 4. In the optical device 100e shown in Figure 18, the same reference numerals are used for components similar to those in the optical device 100 according to Embodiment 1, and their descriptions are not repeated.

[0071] The optical device 100e has an actuator 6P provided at the end of a fixed part 5 connected to the housing 2 as a position adjustment unit for adjusting the alignment between the outermost lens 1 and the inner layer lens 4. The actuator 6P is composed of a piezoelectric element (single layer, multilayer), a motor (voice coil motor), etc. The actuator 6P actively adjusts the alignment of the inner layer lens 4 with respect to the outermost lens 1 based on a control signal from a control circuit (not shown) that detects alignment fluctuations from the image acquired by the image sensor 8 or the output of a sensor provided on the inner layer lens 4, etc. The actuator 6P may also be provided at the end of the fixed part 5 connected to the inner layer lens 4.

[0072] As described above, in the optical device 100e according to Embodiment 4, the position adjustment unit is an actuator 6P provided at the end of the fixed unit 5. This allows the optical device 100e to actively adjust the alignment in response to fluctuations in the alignment of the inner layer lens 4 with respect to the outermost layer lens 1, thereby improving the image quality obtained from the image sensor.

[0073] (Other variations) The imaging unit 200 according to the above-described embodiment may include a camera, LiDAR, radar, etc. Alternatively, multiple imaging units may be arranged side-by-side.

[0074] The imaging unit 200 according to the above-described embodiment is not limited to an imaging unit installed in a vehicle, and can be similarly applied to any imaging unit that includes an optical device and an image sensor arranged so that the light-transmitting material is in the field of view direction, and where it is necessary to remove foreign matter from the light-transmitting material.

[0075] The embodiments disclosed herein should be considered in all respects to be illustrative and not restrictive. The scope of the invention is indicated by the claims rather than by the foregoing description, and all modifications within the meaning and scope of the claims are intended to be included. [Explanation of Symbols]

[0076] 1. Outermost lens, 2. Housing, 3. Vibrator, 4. Inner lens, 4a. Inner lens barrel, 5. Fixing part, 6. Position adjustment part, 6P. Actuator, 7. Piezoelectric element, 8. Image sensor, 9. Circuit board, 10. Case, 100, 100a~100e. Optical device, 200. Imaging unit

Claims

1. A light-transmitting material that transmits light of a predetermined wavelength, A housing that holds the light-transmitting body, A vibrating body that vibrates the light-transmitting material held in the housing, Within the housing, a first lens is provided at a position opposite to the light-transmitting body, A fixing part for fixing the first lens to the housing, The fixed portion is provided with a position adjustment unit for adjusting the alignment of the first lens with respect to the light-transmitting body, The fixing portion fixes the first lens to the housing by connecting it to a portion of the inner wall surface of the housing that is parallel to the optical axis of the light-transmitting body and is a node of vibration caused by the vibrating body.

2. The optical apparatus according to claim 1, wherein the light-transmitting body is a second lens.

3. The optical device according to claim 1 or claim 2, wherein the vibrating body has a piezoelectric element provided on at least one surface.

4. The optical apparatus according to claim 1 or claim 2, wherein the fixed part has a smaller mechanical quality factor Qm than the housing.

5. The optical apparatus according to claim 4, wherein the fixing part is made of resin.

6. The optical apparatus according to claim 1 or claim 2, wherein the position adjustment part is provided at the end of the fixed part connected to the housing.

7. The optical apparatus according to claim 1 or claim 2, wherein the position adjustment part is provided at the end of the fixing part connected to the first lens.

8. The optical apparatus according to claim 6, wherein the position adjustment part has a screw portion at the end of the fixing part and a groove portion corresponding to the screw portion, and adjusts the alignment of the first lens with respect to the light-transmitting body by changing its position.

9. The optical apparatus according to claim 6, wherein the fixing portion has an ultraviolet light-transmitting member or at least one window portion at its end, and by transmitting ultraviolet light, the member or window portion allows an ultraviolet-curable adhesive between the member or window portion and a component located opposite to it to be cured after adjusting the alignment of the first lens with respect to the light-transmitting body.

10. The optical apparatus according to claim 6, wherein the fixing portion has at least one slit at its end, and the slit transmits ultraviolet light, thereby allowing an ultraviolet-curable adhesive provided between the slit and a component located opposite the slit to be cured after adjusting the alignment of the first lens with respect to the light-transmitting body.

11. The optical device according to claim 6, wherein the position adjustment unit is an actuator provided at the end of the fixed unit.

12. The light-transmitting body or the vibrating body has a first planar portion, The first lens or the holder of the first lens has a second planar portion, The optical apparatus according to claim 1 or claim 2, wherein the first planar portion and the second planar portion are in contact with each other.

13. The light-transmitting body or the vibrating body has a first tapered portion, The first lens or the holder of the first lens has a second tapered portion, The optical apparatus according to claim 1 or claim 2, wherein the first tapered portion and the second tapered portion are capable of contacting each other.

14. The light-transmitting body or the vibrating body has a first fitting portion, The first lens or the holder of the first lens has a second fitting portion, The optical device according to claim 1 or claim 2, wherein the first fitting portion and the second fitting portion are fittable.

15. The optical apparatus according to claim 1 or claim 2, An imaging unit comprising an image sensor arranged such that the light-transmitting body and the first lens are in the field of view direction.

Images