Lens unit and camera module

Abstract

To provide a lens unit and a camera module in which an extension part of a planar heater provided in a lens barrel can be easily drawn around in the lens barrel and led outside.SOLUTION: A lens unit includes: a lens barrel 12 for storing and holding optical components such as a plurality of lenses or the like; and a planar heater 50 capable of heating a first lens 13 positioned closest to an object. The lens barrel 12 has an inner peripheral surface formed into a polygonal shape with eight or more sides and includes a storage / holding part S for storing and holding the optical component positioned closer to an image more than the first lens 13. The planar heater 50 includes: a heating part 51 for heating the first lens 13; and a belt-like extension part 52 for supplying electricity to the heating part 51. The storage / holding part S includes an insertion groove 55 which extends in an axis direction of the lens barrel 12 and which has a larger width than that of the extension part 52. The lens barrel 12 includes a lead-out hole 56 which leads the extension part 52 inserted into the insertion groove 55 outside and which communicates with the insertion groove 55.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a lens unit and a camera module that can constitute an on-board camera mounted on a vehicle such as an automobile. [Background technology]

[0002] Cameras that are installed outdoors, such as surveillance cameras and in-vehicle cameras, are known. In such cameras installed outdoors, ice and snow may adhere to the front of the lens when it snows. In addition, when the outside temperature drops below freezing, the front of the lens may freeze and frost may adhere to the front of the lens. In such cases, the adhesion to the front of the lens makes the captured image unclear, and the imaging performance of the camera is reduced. In recent years, vehicles have come to be equipped with cameras (vehicle-mounted cameras), and images captured by the vehicle-mounted cameras are used for functions such as automatic braking and automatic driving. These functions control the running of the vehicle, and a deterioration in the imaging function of the vehicle-mounted camera may lead to accidents, etc. Therefore, there is a demand for the development of a camera equipped with a snow-melting function that melts the snow adhering to the front of the lens. Furthermore, the lens unit of an on-vehicle camera requires strength, waterproofing, chemical resistance, high temperature durability, etc., since the side facing the subject to be imaged (object side) is exposed to the outside of the vehicle. It is also necessary to prevent the lenses from fogging up due to temperature changes.

[0003] Patent Document 1 discloses a lens unit that ensures an airtight state inside the lens barrel in order to prevent freezing of the front surface of the lens and fogging of the lens. In this lens unit, four lenses are arranged in the lens barrel along the optical axis direction. On the object side, sealing is achieved by disposing an O-ring between the lens closest to the object and the inner peripheral surface of the lens barrel. On the image side (image sensor side), sealing is achieved by attaching an optical filter to the lens barrel via an adhesive. In this way, the object side seal and the image side seal ensure airtightness inside the lens barrel, and fogging of the lens is prevented. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2008-233512 A Summary of the Invention [Problem to be solved by the invention]

[0005] However, even if the inside of the lens barrel is kept airtight as described above, it is difficult to ensure a completely airtight state, and when the difference between the outside air temperature and the temperature inside the lens unit becomes large, the water vapor inside the lens unit condenses and condensation occurs on the lens surfaces. In particular, condensation is likely to occur in the inter-lens space between the first lens (the lens closest to the object) which is most affected by the temperature difference with the outside, and the adjacent second lens, particularly on the back surface of the first lens.

[0006] For this reason, in order to remove the condensation on the back surface of the first lens, it is conceivable to heat the first lens with a planar heater such as an FPC heater. The planar heater is formed in a doughnut plate shape and includes a heating portion that heats the first lens and a band-shaped extension portion that extends from the heating portion and supplies electricity to the heating portion. On the other hand, the lens barrel has an inner surface formed in a circular shape and has a storage and holding section that stores and holds multiple lenses, but the outer surface of the lens is abutted against the storage and holding section to position the lens radially, making it difficult to route the extension portion of the surface heater around inside the lens barrel and lead it out to the outside.

[0007] Therefore, by forming the inner surface of the accommodating and holding portion into a polygonal shape and supporting a circular lens at multiple points on this inner surface, a gap is formed between the inner surface of the accommodating and holding portion and the outer surface of the lens.By passing the extension portion of the surface heater through this gap, the extension portion can be routed within the lens barrel. However, the electrical wiring formed on the extension needs to have a certain width because it is necessary to reduce the electrical resistance so as not to generate heat, and so the extension itself needs to have a certain width. In other words, the extension has a strip of copper foil, and because the copper foil needs a certain width to reduce the electrical resistance, the extension needs to have a certain width. For this reason, not only is it difficult to pass the extension through the gap, but if you try to pass it through forcibly, the extension may hit the outer peripheral surface of the lens, causing the lens to become misaligned (eccentric).

[0008] The present invention has been made in consideration of the above-mentioned circumstances, and aims to provide a lens unit and a camera module in which the extension portion of a planar heater provided inside the lens barrel can be easily routed within the lens barrel and led out to the outside. [Means for solving the problem]

[0009] In order to solve the above problems, the present invention provides a lens unit including a plurality of optical components, such as lenses and spacers, arranged along an optical axis, a lens barrel that houses and holds the plurality of optical components, and a planar heater that can heat a first lens located closest to an object, the lens barrel includes an inner circumferential surface formed into a polygonal shape having at least one side of an octagon, the lens barrel including a housing and holding portion configured to house and hold the optical component located on the image side of the first lens, the planar heater includes a heating portion that heats the first lens, and a band-shaped extension portion that extends from the heating portion and supplies electricity to the heating portion, an insertion groove extending in an axial direction of the lens barrel and having a groove width greater than a width of the extension portion is provided in the housing / holding portion; The lens barrel is characterized in that an outlet hole is provided in communication with the insertion groove for leading out the extension portion inserted into the insertion groove to the outside.

[0010] Here, in the lens barrel, a spacer may be provided between adjacent lenses in the optical axis direction, and the spacer is accommodated in the accommodation and holding portion. Therefore, in the present invention, the lenses, spacers, etc. are regarded as optical components. In addition, "polygonal shape" includes a shape in which the inner peripheral surface of the accommodating and holding part is a regular polygon of octagon or more in plan view (viewed in the axial direction of the lens barrel), a polygon other than a regular polygon of octagon or more, and a shape that is a combination of eight or more straight sides arranged at a predetermined interval in the circumferential direction and arcs arranged to connect adjacent sides in the circumferential direction, but also includes a shape with eight or more flat surfaces that can support the outer periphery of the lens at points (point contact). Making the inner peripheral surface of the accommodating and holding part a "regular polygon" allows for even holding (even distribution of stress), which is more effective in axial alignment of the lens. As the planar heater, for example, an FPC heater or an organic PTC heater is used.

[0011] In the present invention, the storage and holding section, which stores and holds optical components such as lenses and spacers, is provided with an insertion groove that extends in the axial direction of the lens barrel and has a groove width wider than the width of the extension section.By inserting the extension section into the insertion groove, the extension section can be easily pulled around within the lens barrel.Furthermore, the lens barrel is provided with an outlet hole that is connected to the insertion groove for leading the extension section inserted into the insertion groove to the outside.Therefore, the extension section inserted into the insertion groove can be easily led out to the outside from the outlet hole. Furthermore, since the extending portion of the planar heater does not interfere with the optical components, the optical components will not become decentered (displaced) even if the extending portion is routed inside the lens barrel.

[0012] In the above-described configuration of the present invention, the outlet hole may be provided in a peripheral wall of the lens barrel.

[0013] According to this configuration, since the outlet hole is provided in the peripheral wall of the lens barrel, the extension of the sheet heater can be easily led out from the peripheral wall of the lens barrel.

[0014] In the above-described configuration of the present invention, the outlet hole may be provided in an end wall of the lens barrel on the image side.

[0015] According to this configuration, since the outlet hole is provided in the end wall of the lens barrel on the image side, the extension of the sheet heater can be easily led out from the end wall of the lens barrel.

[0016] In the above-mentioned configuration of the present invention, an angle formed by a line connecting both ends of the insertion groove in a width direction and a center of the accommodating and holding portion may be within 60°.

[0017] With this configuration, the angle formed by the lines connecting both ends of the insertion groove in the width direction and the center of the accommodating and holding portion is within 60°, so that the outer peripheral surface of a circular optical component can be held at six or more points in the accommodating and holding portion, whose inner peripheral surface is formed into a polygonal shape of octagon or more, thereby enabling the optical component lens to be held stably.

[0018] In the above-mentioned configuration of the present invention, the groove width of the insertion groove may be within 3.5 mm.

[0019] According to this configuration, since the groove width of the insertion groove is 3.5 mm or less, the extension portion of the sheet heater, which has a width of 3.5 mm or less, can be easily inserted into the insertion groove.

[0020] A camera module according to the present invention includes the lens unit. According to this configuration, the effects of the lens unit described above can be obtained in the camera module. Effect of the Invention

[0021] According to the present invention, the extension portion of the sheet heater provided inside the lens barrel can be easily routed inside the lens barrel and led out to the outside. [Brief description of the drawings]

[0022] [Figure 1] FIG. 1 is a schematic cross-sectional view of a lens unit according to a first embodiment of the present invention. [Diagram 2] 1A is a plan view showing a first example of the lens barrel, and FIG. 1B is a plan view showing a second example of the lens barrel. [Diagram 3] FIG. 2 is a perspective view of the lens barrel as viewed obliquely from above. [Figure 4] FIG. 2 is another perspective view of the lens barrel as viewed obliquely from above. [Diagram 5]10 is a schematic diagram showing a state in which the lens is supported by the housing and holding portion according to the first embodiment; FIG. [Figure 6] FIG. 2 is a schematic cross-sectional view of the camera module according to the first embodiment. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] 11 is a plan view showing a state in which the spacer is housed and held in the lens barrel. FIG. [Figure 10] FIG. 11 is a schematic cross-sectional view of a lens unit according to a second embodiment of the present invention. [Figure 11] FIG. 2 is a perspective view of the lens barrel as viewed obliquely from above. [Figure 12] FIG. 2 is a perspective view of the lens barrel as viewed obliquely from below. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The lens unit of this embodiment described below is particularly intended for a camera module such as an in-vehicle camera, and is fixedly installed on the outer surface of a vehicle, with wiring drawn into the vehicle and connected to a display or other devices. In addition, hatching is omitted for the lenses and spacers in all drawings.

[0024] (First embodiment) 1 shows a lens unit 11 according to a first embodiment of the present invention. As shown in the figure, the lens unit 11 of this embodiment includes a cylindrical lens barrel 12 made of, for example, resin, and a plurality of lenses arranged in the lens barrel 12 that are circular in plan view, for example, five lenses consisting of a first lens 13, a second lens 14, a third lens 15, a fourth lens 16, and a fifth lens 17 from the object side (the upper side in FIG. 1), and three aperture members 22a, 22b, and 22c. Further, a groove is provided on the bottom surface of the lens barrel 12, extending radially from the inner periphery of the bottom surface of the lens barrel 12 toward the portion not in contact with the lens 17. This groove is a groove for allowing air to circulate for airtightness testing. In this embodiment, the first lens 13, the second lens 14, the third lens 15, the fourth lens 16, the fifth lens 17, the aperture members 22a, 22b, and 22c, and a spacer 30 described later are defined as optical components.

[0025] Of the three diaphragm members 22a, 22b, and 22c, the first diaphragm member 22a from the object side is disposed between the second lens 14 and the third lens 15. The second diaphragm member 22b from the object side is disposed between the third lens 15 and the fourth lens 16. The third diaphragm member 22c from the object side is disposed between the fourth lens 16 and the fifth lens 17. The aperture member 22a is an "aperture diaphragm" that limits the amount of transmitted light and determines the F-number, which is an index of brightness. The aperture members 22b and 22c are "light blocking diaphragms" that block light rays that cause ghosts and light rays that cause aberrations. An in-vehicle camera equipped with such a lens unit 11 includes the lens unit 11, a board having an image sensor (not shown), and an installation member (not shown) for installing the board on a vehicle such as an automobile.

[0026] The lenses 13, 14, 15, 16, and 17 housed in the lens barrel 12 are stacked and arranged with their optical axes aligned, and the lenses 13, 14, 15, 16, and 17 are arranged along a single optical axis O to form a lens group L used for imaging. In this case, the first lens 13, which is located closest to the object side and which constitutes the lens group L, is a spherical glass lens having a flat surface on the object side and a concave surface on the image side, and the second lens 14 is a spherical glass lens having convex curved surfaces on both the object side and the image side. The other lenses 15, 16, and 17 are resin lenses, but are not limited to this (for example, the first lens 13 and the second lens 14 may be resin lenses; when the first and second lenses 13 and 14 are made of resin, the difference between the linear expansion coefficients of the first lens 13 and the second lens 14 is, for example, 40×10-6 / K(m) or more).

[0027] Furthermore, lens barrel 12 has spacer 30 provided between first lens 13 and third lens 15, and has inter-lens space SL surrounded by first lens 13, third lens 15, spacer 30, and second lens 14, and first lens 13 and spacer 30, and spacer 30 and third lens 15 may be bonded to each other so that the inter-lens space SL is sealed from the outside. The number of lenses and spacers, and the materials of the lenses, spacers and lens barrel can be set as desired depending on the application, etc. The surfaces of these lenses 13, 14, 15, 16, and 17 may be provided with an anti-reflection film, a hydrophilic film, a water-repellent film, or the like, as required.

[0028] The spacer 30 is formed in a cylindrical shape, and the second lens 14 is held at its inner lower end. That is, the spacer 30 has a crimped portion 31 at its lower end edge on the inner diameter side, and this crimped portion 31 is thermally crimped radially inward so as to press the opposing surface 14a of the second lens 14 against the opposing surface 30b of the spacer 30 in the optical axis direction. In this manner, the facing surface 14 a of the second lens 14 is pressed against the facing surface 30 b of the spacer 30 by the crimping portion 31 , whereby the second lens 14 is held by the spacer 30 .

[0029] In this embodiment, an O-ring 26 serving as a seal member is interposed between the first lens 13 located closest to the object and the lens barrel 12 to prevent water and dust from entering the lens group L inside the lens barrel 12. In this case, a stepped reduced diameter portion 13e having a smaller diameter at the image side portion of the lens 13 is provided on the outer circumferential surface 13d of the first lens 13, and an O-ring 26 is attached to this reduced diameter portion 13e, and the O-ring 26 is compressed in the radial direction between the outer circumferential surface 13d of the first lens 13 and the inner circumferential surface 12a of the lens barrel 12, thereby sealing the object side end of the lens barrel 12. In addition, the sealing member interposed between the first lens 13 and the lens barrel 12 is not limited to O-ring 26, but may be in any form as long as it is an annular body that can seal between the first lens 13 and the lens barrel 12.

[0030] Furthermore, with lens group L assembled and housed in lens barrel 12, crimping portion 23 at its object side end (upper end in FIG. 1) is thermally crimped radially inward, thereby fixing first lens 13 located closest to the object side of lens group L to the object side end of lens barrel 12 in the optical axis direction by crimping portion 23. In this case, to ensure stable crimping, the portion of glass lens 13 where crimping portion 23 is pressed is formed as flat portion 13b that is cut obliquely into a plane.

[0031] Furthermore, lens barrel 12 has, at its end on the image side (the lower end in FIG. 1), an inner flange portion 24 having an opening with a diameter smaller than that of fifth lens 17. By this inner flange portion 24 and crimped portion 23, multiple lenses 13, 14, 15, 16, 17 and diaphragm members 22a, 22b, 22c that constitute lens group L within lens barrel 12 are held and fixed in the optical axis direction.

[0032] The lens barrel 12 is provided with a housing / holding section S that houses and holds optical components such as the lenses 15, 16, and 17, and a spacer 30 provided between the lenses 13 and 15 adjacent to each other in the optical axis direction. As shown in Figures 2 and 3, the inner surface of the accommodating and holding section S is formed into a polygonal shape with at least an octagon. In this embodiment, however, the shape is a combination of 12 straight sides (chords) arranged at predetermined intervals in the circumferential direction and 12 circular arcs arranged to connect adjacent sides (chords) in the circumferential direction. The inner diameter of the housing / holding section S becomes smaller in stages from the object side to the image side. Correspondingly, the outer diameters of the spacer 30 and the lenses 15, 16, and 17 become smaller from the object side to the image side. Basically, the outer diameters of the spacer 30 and the lenses 15, 16, and 17 are approximately equal to the inner diameters of the portions of the housing / holding section S of the lens barrel 12 that support the spacer 30 and the lenses 15, 16, and 17.

[0033] That is, to explain lens 15 as a representative example, as shown in Fig. 5, the inner peripheral surface of the accommodating / holding section S is formed into a regular dodecagon shape, and has 12 planar support surfaces SS, and these 12 support surfaces SS are adjacent to each other in the circumferential direction at equal angles. The circumferential center of each support surface SS is a support point SP that supports the outer peripheral surface of lens 15, and there are 12 such support points SP. Therefore, lens 15 is stably supported in a direction perpendicular to the optical axis by the 12 support points SP. As described above, in FIG. 2, the shape is a combination of 12 straight sides (chords) arranged at predetermined intervals in the circumferential direction and 12 circular arcs arranged to connect adjacent sides (chords) in the circumferential direction, but below it will be described as a regular dodecagon.

[0034] Similarly, the inner peripheral surface of the housing / holding section S that houses and holds the spacer 30 and the lenses 16 and 17 is formed in a regular dodecagon shape, but the outer diameter (the distance between the support points SP arranged point-symmetrically about the optical axis) becomes smaller in stages from the object side to the image side. The lenses 16 and 17 are also stably supported in a direction perpendicular to the optical axis by twelve support points SP, but the spacer 30 is stably supported in a direction perpendicular to the optical axis by ten support points SP because an insertion groove 55 is provided in the housing / holding section S as described later.

[0035] 1 to 3, the accommodating and holding section S is composed of a first accommodating and holding section S1 that accommodates and holds spacer 30, a second accommodating and holding section S2 that accommodates lens 15, a third accommodating and holding section S3 that accommodates lens 16, and a fourth accommodating and holding section S4 that accommodates lens 17, and the inner diameter decreases stepwise from the first accommodating and holding section S1 to the fourth accommodating and holding section S4. A stepped surface that protrudes radially inward is provided between adjacent accommodating and holding sections in the axial direction of lens barrel 12. In addition, the accommodating and retaining portion S shown in FIG. 2(a) is positioned such that one vertex of a regular dodecagon is directed toward the widthwise center of the insertion groove 55 described below, whereas the accommodating and retaining portion S shown in FIG. 2(b) is positioned such that one vertex of a regular dodecagon is directed toward a position rotated 15° circumferentially from the widthwise center of the insertion groove 55. In either case, the spacer 30 is supported by ten support points SP.

[0036] The housing / holding portion SU that houses the first lens 13 closest to the object side has an inner circumferential surface formed in a circular shape, and the first lens 13 is housed and held in the housing / holding portion SU. The second lens 14 is formed to have a smaller diameter than the lenses 13 , 15 , 16 , and 17 , and is held and fixed by a spacer 30 . An outer flange portion 25 is provided on the outer circumferential surface of the lens barrel 12 in the shape of a brim and is used when installing the lens barrel 12 on a vehicle-mounted camera.

[0037] Fig. 6 is a schematic cross-sectional view of a camera module 300 of this embodiment having the lens unit 11 shown in Fig. 1. As shown in the figure, the camera module 300 includes the lens unit 11 to which a filter 105 is attached.

[0038] The camera module 300 includes an upper case (not shown) which is an exterior component, and a mount (base) 302 which holds the lens unit 11. The camera module 300 also includes a seal member 303 and a package sensor (imaging element) 304.

[0039] The upper case is a member that exposes the object side end of the lens unit 11 and covers the other portions. The mount 302 is disposed inside the upper case, and has a female thread 302a that screws into the male thread 11a of the lens unit 11. Package sensor 304 is disposed inside mount 302, and is disposed at a position where it receives an image of an object formed by lens unit 11. Package sensor 304 also includes a CCD, CMOS, or the like, and converts the light that is collected and reaches it through lens unit 11 into an electrical signal. The converted electrical signal is then converted into analog data or digital data, which is a component of image data captured by the camera.

[0040] The lens unit 11 and the camera module 300 configured as described above include an FPC heater (planar heater) 50 capable of heating the first lens 13 located closest to the object side, as shown in Fig. 1 and Fig. 7. An organic PTC heater may be used as the planar heater. As shown in FIG. 7, the FPC heater 50 is formed from a flexible printed circuit board, and includes a heating portion 51 that heats the first lens 13, and an extension portion 52 that extends from the heating portion 51 and supplies electricity to the heating portion 51. The heating section 51 is formed in a doughnut plate shape, with an outer diameter approximately equal to the outer diameter of the image-side end face 13a of the first lens 13, and an inner diameter approximately equal to the inner diameter of the image-side end face 13a of the first lens 13. The heating section 51 is formed by forming a semicircular circuit section, which is line-symmetrically formed on a doughnut-shaped base film, in which thin linear copper foil 51a is folded back from the outer periphery to the inner periphery to form a semicircular arc, and this circuit section is configured to generate heat. The extension portion 52 extends linearly radially outward from the heating portion 51 and is formed by arranging two strip-shaped copper foils 52a in parallel on a strip-shaped base fill portion, with one copper foil 52a connected to the anode of the power source and the other copper foil 52a connected to the cathode.

[0041] 2 and 3, the accommodating and holding portion S is provided with an insertion groove 55 extending in the axial direction of the lens barrel 12. This insertion groove 55 has a groove width wider than the width of the extension portion 52 of the FPC heater 50, and a groove depth deeper than the thickness of the extension portion 52. In addition, the insertion groove 55 extends from the object side end of the first accommodating and holding portion S1 to a position slightly closer to the object side than the image side end of the first accommodating and holding portion S1. The heating portion 51 of the FPC heater 50 is in close contact with the image-side end face 13 a of the lens 13 , and the extension portion 52 is directed toward the insertion groove 55 and inserted into the insertion groove 55 .

[0042] Further, a lead-out hole 56 is provided in the peripheral wall of the lens barrel 12 so as to communicate with the insertion groove 55. The lead-out hole 56 is a rectangular hole, and the hole width is equal to the groove width of the insertion groove 55. The lead-out hole 56 is formed so as to penetrate the peripheral wall of the lens barrel 12. The outlet of the lead-out hole 56 is located in the peripheral wall of the lens barrel 12 above the outer flange portion 25. This type of outlet hole 56 is intended to lead out the extension portion 52 of the FPC heater 50 inserted into the insertion groove 55 to the outside of the lens barrel 12, and the extension portion 52 inserted into the insertion groove 55 is bent radially outward at approximately a right angle at the entrance of the outlet hole 56, and then inserted into the outlet hole 56 to be led out to the outside.

[0043] In this embodiment, as shown in FIG. 2, the angle θ formed by the line connecting both ends in the width direction of the insertion groove 55 and the center O of the accommodating and holding portion S (first accommodating and holding portion S1) is within 60°. As shown in Fig. 2(a), the first accommodating and holding portion S1 has an inner peripheral surface formed in a regular polygonal shape having at least one regular dodecagon, but a part of the inner peripheral surface is cut out into a rectangular groove, so that two of the twelve support surfaces SS are removed. Therefore, the spacer 30 is supported by ten support points SP. Therefore, even if the insertion groove 55 is formed, the spacer 30 can be stably supported. 2(b), the first accommodating and holding portion S1 has an inner peripheral surface formed in a regular polygonal shape having at least one regular dodecagon, but a part of the inner peripheral surface is cut out into a rectangular groove, so that one support surface SS and less than half of two support surfaces SS out of the twelve support surfaces SS are cut out. Therefore, the spacer 30 is supported by ten support points SP. Therefore, even if the insertion groove 55 is formed, the spacer 30 can be stably supported.

[0044] 8, the lenses 15-17 and the spacer 30 have outer diameter portions formed by a cylindrical surface, but a flat surface 30a is formed on a part of the cylindrical surface to form a D-cut shape. It is preferable to arrange the D-cut portion of such a D-cut shape so as to face the insertion groove 55. The same applies to the second embodiment described later. The flat surface 30a is a portion that becomes a gate when the lenses 15-17 and the spacer 30 are molded, and the flat surface 30a is a portion that is not originally in contact with the support surface SS of the first accommodating / holding portion S1. Therefore, as shown in Fig. 9, by arranging the flat surface 30a in the insertion groove 55, the spacer 30 can be supported by ten support points SP. In addition, between the flat surface 30a arranged in the insertion groove 55 and the groove bottom surface of the insertion groove 55, there is a sufficient gap to allow the extension portion 52 of the FPC heater 50 to be inserted.

[0045] In this embodiment, the groove width W of the insertion groove 55 is set to 3.5 mm or less as shown in Fig. 2. As described above, when the groove width of the insertion groove 55 is set to an angle θ of 60° or less, the groove width of the insertion groove 55 increases as the outer diameter of the spacer 30 increases. Therefore, in order to prevent the groove width W from becoming excessively large, the groove width W of the insertion groove 55 is specified to be 3.5 mm or less.

[0046] As described above, according to this embodiment, the first accommodating and holding portion S1, which accommodates and holds the spacer 30, is provided with an insertion groove 55 extending in the axial direction of the lens barrel 12 and having a groove width wider than the width of the extension portion 52 of the FPC heater 50. Therefore, by inserting the extension portion 52 into the insertion groove 55, the extension portion 52 can be easily routed within the lens barrel. Furthermore, the peripheral wall of the lens barrel 12 is provided with an outlet hole 56 communicating with the insertion groove 55 for guiding the extension portion 52 inserted into the insertion groove 55 to the outside. Therefore, the extension portion 52 inserted into the insertion groove 55 can be easily guided to the outside from the outlet hole 56. Furthermore, since the extension 52 of the FCC heater 50 does not interfere with the spacer 30 or the lenses 15, 16, and 17, even if the extension 52 is routed inside the lens barrel 12, the spacer 30 and the lenses 15, 16, and 17 will not become decentered.

[0047] Furthermore, since the lead-out hole 56 is provided in the peripheral wall of the lens barrel 12, the extension portion 52 of the FPC heater 50 can be easily led out from the peripheral wall of the lens barrel 12. Furthermore, since the angle formed by the lines connecting both ends of the insertion groove 55 and the center of the first accommodating and retaining portion S1 is within 60°, the outer peripheral surface of the spacer 30 can be held by ten support points SP in the first accommodating and retaining portion S1, whose inner peripheral surface is formed into a regular dodecagon, and therefore the spacer 30 can be held stably. In addition, since the groove width of the insertion groove 55 is 3.5 mm or less, the extension portion 52 of the FPC heater 50, which has a width of 3.5 mm or less, can be easily inserted into the insertion groove 55.

[0048] Second embodiment 10 to 12 show the second embodiment, with Fig. 10 being a cross-sectional view of lens unit 11, Fig. 11 being a perspective view of lens barrel 12 seen diagonally from above, and Fig. 12 being a perspective view of lens barrel 12 seen diagonally from below. Lens unit 11 of the second embodiment differs from lens unit 11 of the first embodiment in the configurations of the insertion grooves and lead-out holes, and so this point will be explained below, and configurations that are the same as those in the first embodiment will be given the same reference numerals and their explanations may be omitted.

[0049] As shown in Figs. 10 to 12, the accommodating / holding portion S is provided with an insertion groove 65 extending in the axial direction of the lens barrel 12. The insertion groove 65 has a groove width wider than the width of the extension portion 52 of the FPC heater 50, and a groove depth deeper than the thickness of the extension portion 52. The insertion groove 65 extends from the object side end of the first accommodating / holding portion S1 to the upper surface of the inner flange portion 24 located at the bottom of the fourth accommodating / holding portion S4. The groove bottom of the insertion groove 65 extends straight from the first accommodating / holding portion S1 to the second accommodating / holding portion S2, and forms a step by extending obliquely radially inward at the boundary between the second accommodating / holding portion S2 and the third accommodating / holding portion S3, and then extends straight from the third accommodating / holding portion S3 to the fourth accommodating / holding portion S4. In this embodiment, the insertion groove 65 extends from the object side end of the first accommodating / holding portion S1 to the upper surface of the inner flange portion 24 located at the bottom of the fourth accommodating / holding portion S4, so that the spacer 30 housed and held in the first accommodating / holding portion S1, the lens 15 housed and held in the second accommodating / holding portion S2, the lens 16 housed and held in the third accommodating / holding portion S3 and the lens 17 housed and held in the fourth accommodating / holding portion S4 are each stably supported in a direction perpendicular to the optical axis by ten support points SP. The heating portion 51 of the FPC heater 50 is in close contact with the image-side end face 13 a of the lens 13 , and the extension portion 52 is directed toward the insertion groove 65 and inserted into the insertion groove 65 .

[0050] Further, in the end wall 24 on the image side of the lens barrel 12, i.e., in the inner flange portion 24, a lead-out hole 66 is provided in communication with the insertion groove 65. The lead-out hole 66 is a rectangular hole, and the hole width is equal to the groove width of the insertion groove 65. The lead-out hole 66 is formed so as to penetrate the end wall (inner flange portion) 24 of the lens barrel 12. This type of exhaust hole 66 is intended to exhaust the extension portion 52 of the FPC heater 50 inserted into the insertion groove 65 to the outside of the lens barrel 12, and the extension portion 52 inserted into the insertion groove 65 is bent at approximately a right angle at the entrance of the exhaust hole 66, and then inserted into the exhaust hole 66 and exhausted to the outside from the inner flange portion 24.

[0051] According to this embodiment, not only can the same effects as in the first embodiment be obtained, but also, since the insertion groove 65 extends in the axial direction of the lens barrel 12 and an outlet hole 66 communicating with this insertion groove 65 is provided in the image-side end wall 24 of the lens barrel 12, the extension portion 52 of the FPC heater 50 can be easily led out from the end wall 24 of the lens barrel 12.

[0052] In the first and second embodiments, the spacer 30 and the lenses 15, 16, and 17 are accommodated and held in the accommodating and holding portion S, but the accommodating and holding portion S may accommodate and hold only a plurality of lenses. In other words, the spacer 30 may not be provided. In addition, in the first and second embodiments, the inner circumferential surface of the storage / holding portion SU that stores and holds the lens 13 located closest to the object is formed in a circular shape, but the inner circumferential surface of the storage / holding portion SU may be formed in a polygonal shape having an octagon or more sides. [Explanation of symbols]

[0053] 11 Lens unit 12 Telescope tube 13, 14, 15, 16, 17 Lenses (optical components) 24 Inner flange (end wall) 30 Spacer (optical component) 50 FPC heater (surface heater) 51 Heating section 52 Extension 55,65 Insertion groove 56,66 Outlet hole L lens group O optical axis S Retaining part S1 First storage and holding section S2 Second storage and holding section S3 3rd storage unit S4 4th storage and holding section

Claims

1. A lens unit including a plurality of optical components such as lenses and spacers arranged along an optical axis, a lens barrel that houses and holds the plurality of optical components, and a planar heater that can heat a first lens located closest to an object, the lens barrel includes a housing and holding portion that houses and holds the optical component located on the image side of the first lens, the planar heater includes a heating portion that heats the first lens, and a band-shaped extension portion that extends from the heating portion and supplies electricity to the heating portion, an insertion groove extending in an axial direction of the lens barrel and having a groove width greater than a width of the extension portion is provided in the housing / holding portion; The lens unit is characterized in that the lens barrel is provided with an outlet hole communicating with the insertion groove for leading out the extension portion inserted into the insertion groove to the outside.

2. 2. The lens unit according to claim 1, wherein the outlet hole is provided in a peripheral wall of the lens barrel.

3. 2. The lens unit according to claim 1, wherein the outlet hole is provided in an end wall of the lens barrel on the image side.

4. 4. The lens unit according to claim 1, wherein an angle between both ends of the insertion groove in the width direction and a line connecting the center of the accommodating and holding portion is within 60°.

5. 5. The lens unit according to claim 1, wherein the groove width of the insertion groove is within 3.5 mm.

6. A camera module comprising the lens unit according to any one of claims 1 to 5.

Images