JP6014468B2 - Optical unit and imaging device - Google Patents

Description

  The present invention relates to an optical unit capable of applying a resin lens on the outermost part while maintaining high environmental resistance performance for a long period of time.

  There are known cameras that are frequently exposed to the outdoor environment, such as in-vehicle cameras and surveillance cameras. An optical unit used for such an outdoor camera is required to have improved environmental resistance such as scratch resistance, chemical resistance, and weather resistance, and to reduce manufacturing costs.

  Conventionally, a glass lens is arranged on the most object side of an optical unit having a plurality of lenses in order to have high environmental resistance, and a resin lens is arranged inside to reduce manufacturing costs. It is disclosed (see Patent Document 1).

JP 2010-32902 A

  However, there is a greater demand for a reduction in manufacturing cost, and it is required that a lens made of resin be used as the lens on the most object side. Resinous lenses have relatively low environmental resistance, and are difficult to apply to the outermost lens exposed to rainwater or the like. Therefore, by applying a hard coat to a resin lens, it is possible to impart high environmental resistance to the resin lens.

  However, since it is necessary to apply a hard coat while controlling the film thickness in order to impart desired optical characteristics, it is difficult to apply a hard coat to the entire lens. Therefore, rainwater can infiltrate from a location where the hard coat is not applied, and it can be difficult to maintain environmental resistance for a long period of time.

  Accordingly, an object of the present invention made in view of such circumstances is to provide an optical unit that can apply a resin lens to the most object side while maintaining high environmental resistance for a long period of time.

In order to solve the above-described problems, the optical unit according to the first aspect is
A lens effective portion that functions as a lens, and extends radially outward from an end portion of the lens effective portion, and an angle of a perpendicular to the optical axis of the lens effective portion is greater than an angle of a perpendicular at an end of the lens effective portion to the optical axis An inclined portion that is largely less than 90 °, a holding portion that extends radially outward of the inclined portion and includes a groove-shaped accommodation portion positioned around the inclined portion, and the lens effective portion and the inclined portion. An imaging lens having a hard coat,
A fixing unit for fixing the imaging lens in a lens barrel from a surface on the imaging target side of the holding unit;
A first waterproof part that is accommodated in the accommodating part and waterproofs between the holding part and the fixed part is provided.

An optical unit according to the second aspect is
The first waterproof part is preferably an elastic member.

An optical unit according to the third aspect is
The fixing unit fixes the imaging lens by being attached to the lens barrel,
It is preferable that the first waterproof portion is waterproof between the lens barrel and the fixed portion.

An optical unit according to the fourth aspect is
It is preferable that the fixing portion includes a pressing portion that presses the first waterproof portion against the holding portion and the lens barrel when the lens barrel is attached to the lens barrel.

An optical unit according to the fifth aspect is
The first waterproof part preferably has a V-shaped cross section.

An optical unit according to the sixth aspect is
The first waterproof part is preferably a cured adhesive.

An optical unit according to the seventh aspect is
The adhesive is preferably a thermosetting adhesive.

An optical unit according to the eighth aspect is
The imaging lens is preferably formed of a resin member.

An optical unit according to the ninth aspect is
A part of the inner diameter of the lens barrel is substantially equal to the outer diameter of the holding portion, and the lens barrel is formed with a second accommodating portion that accommodates a convex portion protruding radially outward from the holding portion. It is preferable.

An optical unit according to the tenth aspect is
It is preferable that a plurality of the second accommodating portions are formed in the lens barrel.

An optical unit according to the eleventh aspect is
The second accommodating portion is preferably a groove formed inside the lens barrel or a notch formed at an end of the lens barrel.

An optical unit according to a twelfth aspect is
It is preferable to further include a second waterproof portion that waterproofs between the fixing portion that fixes the imaging lens by being attached to the lens barrel and the lens barrel.

An imaging apparatus according to a thirteenth aspect is
A lens effective portion that functions as a lens, and extends radially outward from an end portion of the lens effective portion, and an angle of a perpendicular to the optical axis of the lens effective portion is greater than an angle of a perpendicular at an end of the lens effective portion to the optical axis An inclined portion that is largely less than 90 °, a holding portion that extends radially outward of the inclined portion and includes a groove-shaped accommodation portion positioned around the inclined portion, and the lens effective portion and the inclined portion. An imaging lens having a hard coat, a fixing portion for fixing the imaging lens in the lens barrel from a surface on the imaging target side of the holding portion, and being housed in the housing portion, between the holding portion and the fixing portion. an optical unit having a first waterproof part waterproof,
And an imaging device that captures a subject image formed through the optical unit.

  According to the light emitting unit and the imaging apparatus according to the present invention configured as described above, a resin lens can be applied to the object side most while maintaining high environmental resistance for a long period of time.

1 is a cross-sectional view along an optical axis showing a schematic configuration of an imaging apparatus according to a first embodiment of the present invention. It is sectional drawing of the lens barrel of 1st Embodiment before the assembly of an optical unit. It is sectional drawing which shows schematic structure of the imaging device of 1st Embodiment before forming a fixing | fixed part. It is sectional drawing of the lens barrel along the IV-IV line in FIG. It is sectional drawing along the optical axis of the 1st imaging lens. It is a front view of the 1st imaging lens. It is a figure which shows the general coating method of the hard coat to the 1st imaging lens. It is sectional drawing along the optical axis of the lens formed by omitting the inclined part from the first imaging lens. It is a comparison figure for demonstrating the difference in the adhesive strength by the presence or absence of a 1st accommodating part. It is a front view of the imaging lens which provided the convex part in the shape which cut a part of outermost edge. It is sectional drawing along the optical axis which shows schematic structure of the imaging device which concerns on 2nd Embodiment. It is sectional drawing along the optical axis which shows schematic structure of the imaging device which concerns on 3rd Embodiment. It is sectional drawing of the lens-barrel of 3rd Embodiment. It is sectional drawing which shows schematic structure of the imaging device of 3rd Embodiment before mounting | wearing with a fixing | fixed part. It is sectional drawing of the lens-barrel along the surface perpendicular | vertical to an optical axis which shows the modification of the lens-barrel in 2nd Embodiment. It is sectional drawing along the optical axis of an imaging device which shows the modification of the 1st imaging lens of 3rd Embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  First, the optical unit according to the first embodiment of the present invention will be described. FIG. 1 is a cross-sectional view along an optical axis showing a schematic configuration of an imaging apparatus having an optical unit according to the first embodiment.

  As shown in FIG. 1, the imaging device 10 includes an optical unit 11 and an imaging element 12. The optical unit 11 forms a subject image. The image sensor 12 captures a subject image formed through the optical unit 11.

  The optical unit 11 includes a lens barrel 13, a first imaging lens 14, a second imaging lens 15, a third imaging lens 16, a fourth imaging lens 17, a first spacer 18, a second spacer 19, and The first waterproof unit 20 is included.

  As shown in FIG. 2, the lens barrel 13 has an inner hole h penetrating from the image side to the object side (imaging target side). The inner diameter of the inner hole h is formed so as to expand stepwise and partly continuously from the image side to the object side. The lens barrel 13 has a wall portion 21 at the end of the inner hole h on the image side. The wall 21 has a hole 22 at the center for allowing the subject image to pass therethrough.

  The fourth imaging lens 17, the second spacer 19, the third imaging lens 16, the first spacer 18, the second imaging lens 15, and the first imaging lens 14 are sequentially arranged on the object side of the inner hole h. (See FIG. 1). The fourth imaging lens 17, the second spacer 19, the third imaging lens 16, the first spacer 18, the second imaging lens 15, and the first imaging lens 14 are in contact with each other, and the fourth The wall 21 that engages with the imaging lens 17 is the fourth imaging lens 17, the second spacer 19, the third imaging lens 16, the first spacer 18, the second imaging lens 15, and the first imaging lens 17. The displacement of the imaging lens 14 toward the image side is restricted.

  As shown in FIG. 3, the object side end of the lens barrel 13 extends from the outermost edge of the first imaging lens 14 to the object side before the optical unit 11 is assembled. With the fourth imaging lens 17, the second spacer 19, the third imaging lens 16, the first spacer 18, the second imaging lens 15, and the first imaging lens 14 fitted in the inner hole h, By bending the end 23 on the object side of the lens barrel 13 inward, a caulking-like fixing portion 24 is formed on the object side of the lens barrel 13 (see FIG. 1). The fixing unit 24 covers a part of the first imaging lens 14 as will be described later.

  The fixing unit 24 fixes the first imaging lens 14 in the lens barrel 13. Further, the fixing unit 24 fixes the first imaging lens 14 to thereby fix the first imaging lens 14, the second imaging lens 15, the first spacer 18, the third imaging lens 16, and the second spacer. 19 and the displacement of the fourth imaging lens 17 toward the object side is restricted.

  As described above, the optical axes ax of the first imaging lens 14, the second imaging lens 15, the first spacer 18, the third imaging lens 16, the second spacer 19, and the fourth imaging lens 17. The displacement along is regulated and the position along each optical axis ax is defined. The first imaging lens 14, the second imaging lens 15, the first spacer 18, the third imaging lens 16, the second spacer 19, and the first imaging lens 14 are determined by the inner peripheral surface of the lens barrel 13 at the determined position. The displacement of the fourth imaging lens 17 in the direction perpendicular to the optical axis ax is regulated directly or indirectly.

  As shown in FIG. 4, a plurality of second accommodating portions 25 are formed on the inner peripheral surface is of the lens barrel 13 where the first imaging lens 14 is positioned. Each second accommodating portion 25 is a groove that continues to the opening end on the object side. As will be described later, the second accommodating portion 25 accommodates a convex portion formed on the first imaging lens 14. In the first embodiment, for example, four second accommodating portions 25 are provided at equal intervals, that is, at rotational positions every 90 °. However, the number of the second accommodating portions 25 is not limited to four and may not be equal.

  The first imaging lens 14 is, for example, a resin meniscus lens that is convex on the object side. As shown in FIG. 5, the first imaging lens 14 includes a lens effective part 26, an inclined part 27, and a holding part 28.

The lens effective portion 26 is a portion that forms a convex surface that functions as a lens effective surface on the object side. Inclined portion 27 extends from an end portion e of the lens effective portion 26 radially outward, larger than the angle theta ₁ of the perpendicular line at the end e of the lens effective portion 26 the angle theta ₂ of the normal to the optical axis ax is with respect to the optical axis ax , A portion having an inclined surface that is less than 90 °. The holding portion 28 is a portion that extends like a bowl outward in the radial direction of the inclined portion 27.

  The holding part 28 has a first accommodating part 29 that is continuous with the inclined surface of the inclined part 27. The first accommodating portion 29 is a groove formed around the inclined surface of the inclined portion 27, for example. The first accommodating portion 29 is filled with a thermosetting adhesive before the fixing portion 24 is formed. As described above, after the fixing portion 24 is formed, the adhesive is cured by heating. The cured adhesive is interposed between the holding portion 28 and the fixing portion 24, and functions as the first waterproofing portion 20 that waterproofs the holding portion 28 and the fixing portion 24 (see FIG. 1).

  The first imaging lens 14 is formed using a mold, and a gate serving as a resin supply path to the mold is formed as a convex part 30 protruding radially outward from the holding part 28 as shown in FIG. Is done. The outer diameter of the holding part 28 excluding the convex part 30 is substantially equal to the inner diameter of the lens barrel 13 at the position where it is accommodated.

  A hard coat 31 having a uniform film thickness is applied to the object-side surfaces (upper surface in FIG. 5) of the lens effective portion 26, the inclined portion 27, and the holding portion 28. For example, as shown in FIG. 7, the first imaging lenses 14 are arranged on the belt conveyor 32 with the object side surface facing upward, and a hard coat agent 33 is ejected from above the belt conveyor 32 to hard coat. 31 is applied.

  The second imaging lens 15, the third imaging lens 16, and the fourth imaging lens 17 are formed using a mold. The outer diameters of the second imaging lens 15 and the fourth imaging lens 17 are substantially equal to the inner diameter of the lens barrel 13 at the accommodated position. The first spacer 18 and the second spacer 19 are formed to hold the third imaging lens 16 between the second imaging lens 15 and the fourth imaging lens 17 and to function as a diaphragm. The outer diameters of the first spacer 18 and the second spacer 19 are substantially equal to the inner diameter of the lens barrel 13 at the accommodated position.

  According to the optical unit of the first embodiment having the above-described configuration, as described below, the first imaging lens 14 is made of resin on the most object side while maintaining high environmental resistance for a long period of time. The first imaging lens 14 can be applied.

  As described above, by applying the hard coat 31, the resin lens has high environmental resistance. However, in order to give the first imaging lens 14 the desired optical characteristics, it is necessary to apply a hard coat 31 with a film thickness adjusted to the lens effective portion 26. In order to apply the hard coat 31 having an adjusted film thickness without extremely increasing the manufacturing cost, it is desirable to spray the hard coat agent 33 from the surface direction on the object side as described above (see FIG. 7). .

  However, in such a method, it is difficult to apply the hard coat 31 to the entire resin lens, and the first imaging lens 14 may have a hard coat non-application surface. If the hard coat 31 has a non-application surface, rainwater, chemicals, etc. may enter the hard coat 31 from the boundary between the hard coat 31 application surface and the non-application surface, and the first imaging lens 14 is eroded. Therefore, it is difficult to maintain high environmental resistance for a long time.

  Therefore, in the first embodiment, the first waterproof portion 20 waterproofs between the holding portion 28 and the fixing portion 24 that fixes the first imaging lens 14 from the object side surface. It is possible to prevent the non-coated surface from being exposed to the outside, and high environmental resistance can be maintained for a long period of time.

  Moreover, in the above-mentioned hard coat application method, it is difficult to apply the hard coat 31 to a surface other than the surface facing the jet direction of the hard coat agent 33. For example, as illustrated in FIG. 8, the first imaging lens 14 ′ does not include the inclined portion 27, the lens effective portion 26 has a side peripheral surface 34 perpendicular to the optical axis ax, and the side peripheral surface 34 is held. When continuous with the portion 28, the hard coat 31 is not applied to the side peripheral surface 34. Therefore, rainwater can enter between the hard coat 31 and the lens effective portion 26 from the side peripheral surface 34 side.

  Therefore, in the first embodiment, the hard coat 31 can be applied so as to continue from the lens effective portion 26 to the holding portion 28 by providing the inclined portion 27 in the first imaging lens 14. Therefore, since the hard coat 31 can be applied to the entire surface of the first imaging lens 14 exposed to the outside, the high environmental resistance of the first imaging lens 14 can be maintained for a long period of time.

  In the first embodiment, a holding portion 28 is further provided outside the inclined portion 27 in the radial direction. By providing the holding unit 28, the first waterproof unit 20 can be stably held by the first imaging lens 14, and the waterproof property of the first waterproof unit 20 can be improved. is there.

  In the first embodiment, the first accommodating portion 29 is formed in the holding portion 28, and the first waterproof portion 20 can be accommodated. By accommodating the first waterproof part 20 in the first accommodating part 29, it is possible to improve the adhesive strength with respect to the configuration in which the first accommodating part 29 is not formed as described below. .

  As shown in FIG. 9A, in the case of the first imaging lens 14 ″ having the holding portion 28 where the entire object-side surface is flat without forming the first accommodating portion 29, the fixing portion 24 is used. The space formed by the fixing portion 24, the inclined portion 27, and the holding portion 28 is filled with the adhesive 35 after fixing by the adhesive 35. In bonding the first imaging lens 14 ″, the adhesive 35, the holding portion 28, and the fixing are fixed. The adhesive surfaces (see reference sign “A”) with the portion 24 are perpendicular to each other, and at least one of the adhesive surfaces is likely to be subjected to a force that causes the adhesive 35 to peel in a direction perpendicular to the adhesive surface.

  On the other hand, in the first embodiment, the adhesive surfaces of the adhesive 35, the holding portion 28, and the fixing portion 24 (see “B” in FIG. 9B) are parallel to each other. The force that shears the adhesive 35 in the parallel direction is easy to apply, but the peeling force is difficult to apply. Generally, the shear strength of the adhesive is greater than the peel strength. Therefore, according to the first embodiment, the waterproofness of the first waterproof part 20 can be maintained for a long period of time by improving the adhesive strength.

  In the first embodiment, since the adhesive 35 is a thermosetting type, unlike the photo-curing type adhesive, the adhesive 35 is cured by heating from the surroundings even after the fixing portion 24 is formed. It is possible to make it.

  In the first embodiment, the second housing portion 25 is formed in the lens barrel 13. In the case where the first imaging lens 14 is formed using a mold for cost reduction, the convex portion 30 is formed on the first imaging lens 14 as described above. In order to accommodate the imaging lens having the convex portion 30 in the lens barrel 13, as shown in FIG. 10, the convex portion 30 is formed in a shape obtained by cutting a part of the outermost edge of the imaging lens 36. It is common.

  However, since the first imaging lens 14 holds the first waterproof part 20 using the holding part 28, the narrowing of the holding part 28 makes the holding of the first waterproof part 20 unstable and waterproof. It can be difficult to improve. Therefore, in the first embodiment, the second accommodating portion 25 that can accommodate the convex portion 30 is formed in the lens barrel 13, and the holding portion 28 is not narrowed over the entire circumference (see FIG. 6). Can be improved.

  In the first embodiment, a plurality of second accommodating portions 25 are formed. In the conventional optical unit, the optical axis alignment of the lens is performed using the inner peripheral surface of the lens barrel, and the optical axis alignment is finely adjusted by rotating the lens along the inner peripheral surface. In the case where the single second housing portion 25 is formed, the range in which fine adjustment can be performed is narrow even if the second housing portion 25 has play with respect to the convex portion 30. Therefore, in the first embodiment, the adjustment range for fine adjustment of optical axis alignment can be expanded by forming a plurality of second accommodating portions 25.

  Next, a second embodiment of the present invention will be described. In the second embodiment, the configuration of the fixing part and the number of waterproof parts are different from those of the first embodiment. The second embodiment will be described below with a focus on differences from the first embodiment. In addition, the same code | symbol is attached | subjected to the site | part which has the same structure as 1st Embodiment.

  As shown in FIG. 11, the imaging apparatus 100 includes an optical unit 110 and an imaging element 12. The function of the optical unit 110 is the same as that of the first embodiment. The configuration and function of the image sensor 12 are the same as those in the first embodiment.

  The optical unit 110 includes a lens barrel 130, a first imaging lens 14, a second imaging lens 15, a third imaging lens 16, a fourth imaging lens 17, a first spacer 18, a second spacer 19, and a fixed. A part 240, the first waterproof part 20, and the second waterproof part 370 are configured. Configurations of the first imaging lens 14, the second imaging lens 15, the third imaging lens 16, the fourth imaging lens 17, the first spacer 18, the second spacer 19, and the first waterproof portion 20 and The function is the same as in the first embodiment.

  Configurations and functions other than the object-side end of the lens barrel 130 are the same as those in the first embodiment. Therefore, the lens barrel 130 has the wall portion 21 in which the hole portion 22 is formed on the image side, and the wall portion 21 includes the fourth imaging lens 17, the second spacer 19, the third imaging lens 16, and the first imaging lens 16. The displacement of the spacer 18, the second imaging lens 15, and the first imaging lens 14 toward the image side is regulated.

  Similarly to the first embodiment, the lens barrel 130 has the first imaging lens 14, the second imaging lens 15, the first spacer 18, and the third imaging by the inner peripheral surface is of the lens barrel 130. The lens 16, the second spacer 19, and the fourth imaging lens 17 are directly or indirectly restricted from being displaced in a direction perpendicular to the optical axis ax.

  Unlike the first embodiment, the end on the object side of the lens barrel 130 does not extend from the holding unit 28 of the first imaging lens 14 to the object side, and the displacement on the image side of the first imaging lens 14 is the above-described. In such a restricted state, the holding portion 28 of the first imaging lens 14 protrudes from the object side end of the lens barrel 130 toward the object side. In addition, a groove-shaped third accommodating portion 380 is formed at the end of the lens barrel 130 on the object side along the circumference of the end. As will be described later, the third accommodating portion 380 accommodates the second waterproof portion 370.

  Similar to the first embodiment, the lens barrel 130 is formed with a plurality of second accommodating portions 25 on the inner peripheral surface is where the first imaging lens 14 is positioned (see FIG. 4). The second accommodating portion 25 accommodates the convex portion 30 formed on the first imaging lens 14.

  Unlike the first embodiment, the fixing portion 240 is not a part of the lens barrel 130 but an annular retainer that is attached to the lens barrel 130 by, for example, screwing. The fixing unit 240 fixes the first imaging lens 14 within the lens barrel 130 by being attached to the lens barrel 130. As in the first embodiment, the fixing unit 240 fixes the first imaging lens 14 to thereby fix the first imaging lens 14, the second imaging lens 15, the first spacer 18, and the third imaging. The displacement of the lens 16, the second spacer 19, and the fourth imaging lens 17 toward the object side is restricted.

  The fixing portion 240 is formed with a ring portion 390 that projects into the first housing portion 29 of the first imaging lens 14. The ring portion 390 is embedded in the adhesive 35 filled in the first housing portion 29 of the first imaging lens 14 when attached to the lens barrel 130. The adhesive 35 is cured in a state where the ring portion 390 is embedded in the adhesive 35 of the first accommodating portion 29. The cured adhesive 35 functions as the first waterproof part 20 as in the first embodiment.

  The second waterproof part 370 is an O-ring formed of, for example, an elastic member. The second waterproof portion 370 is elastic by being pressed by the lens barrel 130 and the fixing portion 240 when the fixing portion 240 is attached to the lens barrel 130 while being accommodated in the third accommodating portion 380 of the lens barrel 130. Deform. The second waterproof portion 370 waterproofs the space between the lens barrel 130 and the fixed portion 240 by pressing the lens barrel 130 and the fixed portion 240 while elastically deforming.

  Also in the optical unit of the second embodiment configured as described above, the first imaging lens 14 has the inclined portion 27 and the holding portion 28, and the first imaging lens 14 and the fixed portion are fixed by the first waterproof portion 20. The portion 240 can be waterproofed. Therefore, as in the first embodiment, the first imaging lens 14 made of resin can be applied to the most object side while maintaining the high environmental resistance of the first imaging lens 14 for a long period of time. In addition, also with the optical unit of the second embodiment, the first imaging lens 14 has the holding portion 28, so that the waterproofness of the first waterproof portion 20 can be improved. Moreover, since the 1st accommodating part 29 is formed in the holding | maintenance part 28 also by the optical unit of 2nd Embodiment, it becomes possible to maintain the waterproofness of the 1st waterproof part 20 for a long period of time. Moreover, since the adhesive 35 is a thermosetting type also in the optical unit of the second embodiment, the adhesive 35 can be cured after the fixing portion 240 is attached. In addition, since the plurality of second accommodating portions 25 are formed in the lens barrel 130 also by the optical unit of the second embodiment, the waterproofness of the first waterproof portion 20 is improved and the optical axis alignment is finely adjusted. The adjustment range can be expanded.

  Furthermore, according to the optical unit of the second embodiment, even when the retainer is used as the fixing part 240, the rainwater that can enter from between the barrel 130 and the fixing part 240 has the second waterproof part 370. Is waterproof.

  Also, according to the optical unit of the second embodiment, since the ring portion 390 is formed in the fixing portion 240, the bonding surface between the fixing portion 240 and the adhesive 35 is enlarged, so that the bonding strength is improved and the first It is possible to improve the waterproof property of the waterproof part 20.

  Next, a third embodiment of the present invention will be described. In the third embodiment, the configuration of the fixed portion and the configuration of the first waterproof portion are different from those of the first embodiment. The third embodiment will be described below with a focus on differences from the first embodiment. In addition, the same code | symbol is attached | subjected to the site | part which has the same structure as 1st Embodiment.

  As illustrated in FIG. 12, the imaging apparatus 101 includes an optical unit 111 and an imaging element 12. The function of the optical unit 111 is the same as that of the first embodiment. The configuration and function of the image sensor 12 are the same as those in the first embodiment.

  The optical unit 111 includes a lens barrel 131, a first imaging lens 141, a second imaging lens 15, a third imaging lens 16, a fourth imaging lens 17, a first spacer 18, a second spacer 19, and a fixed portion. A part 241 and a first waterproof part 201 are included. The configurations and functions of the second imaging lens 15, the third imaging lens 16, the fourth imaging lens 17, the first spacer 18, and the second spacer 19 are the same as those in the first embodiment.

  The configuration and functions other than the end of the lens barrel 131 on the object side are the same as those in the first embodiment. Therefore, the lens barrel 131 has the wall portion 21 in which the hole portion 22 is formed on the image side, and the wall portion 21 includes the fourth imaging lens 17, the second spacer 19, the third imaging lens 16, and the first imaging lens 16. The displacement of the spacer 18, the second imaging lens 15, and the first imaging lens 141 toward the image side is restricted.

  Similarly to the first embodiment, the lens barrel 131 has a second imaging lens 15, a first spacer 18, a third imaging lens 16, and a second spacer, depending on the inner peripheral surface is of the lens barrel 131. 19 and the fourth imaging lens 17 are directly or indirectly restricted from being displaced in a direction perpendicular to the optical axis ax. However, unlike the first embodiment, the displacement of the first imaging lens 141 in the direction is regulated not by the inner peripheral surface is but by the second imaging lens 15 fitted to the first imaging lens 141. Is done.

  As shown in FIG. 13, on the inner peripheral surface is of the lens barrel 131, a surface facing the side peripheral surface of the holding portion 281 of the first imaging lens 141 is defined as a seating surface 401. The end of the seating surface 401 on the object side is chamfered to form an inclined surface 411 inclined with respect to the seating surface 401.

  Unlike the first embodiment, the fixing portion 241 is an annular retainer that is attached to the lens barrel 131 by, for example, screwing (see FIG. 12). The fixing unit 241 fixes the first imaging lens 141 in the lens barrel 131 by being attached to the lens barrel 131. As in the first embodiment, the fixing unit 241 fixes the first imaging lens 141 to thereby fix the first imaging lens 14, the second imaging lens 15, the first spacer 18, and the third imaging. The displacement of the lens 16, the second spacer 19, and the fourth imaging lens 17 toward the object side is restricted.

  The fixing portion 241 is formed with a pressing portion 421 that protrudes into a space between the seat surface 401 of the lens barrel 131 and the holding portion 281 of the first imaging lens 141 when the lens barrel 131 is mounted. The pressing portion 421 is formed in an annular shape that continues along the annular fixing portion 241. As will be described later, the pressing unit 421 presses the first waterproof unit 201 against the holding unit 281 of the first imaging lens 141 and the inclined surface 411 of the barrel 131.

  Similar to the first embodiment, the first imaging lens 141 includes a lens effective portion 26, an inclined portion 27, and a holding portion 281. The configurations and functions of the lens effective unit 26 and the inclined unit 27 are the same as those in the first embodiment.

  Unlike the first embodiment, the first accommodating portion 29 is not formed in the holding portion 281. Further, the end portion on the object side of the side peripheral surface of the holding portion 281 is chamfered to form an inclined surface that is inclined with respect to the side peripheral surface. On the image side of the holding portion 281, a step to be fitted with the second imaging lens 15 is formed. By fitting the holding portion 281 to the second imaging lens 15, displacement in the direction perpendicular to the optical axis ax is restricted. The outer diameter of the holding portion 281 is shorter than the inner diameter of the seat surface 401, and thus a gap is generated between the holding portion 281 and the seat surface 401.

  Similar to the first embodiment, a hard coat 31 having a uniform film thickness is applied to the object-side surfaces of the lens effective portion 26, the inclined portion 27, and the holding portion 281 of the first imaging lens 141.

  Unlike the first embodiment, the first waterproof part 201 is an elastic member such as an O-ring, for example. As shown in FIG. 14, the cross section along the optical axis ax of the 1st waterproof part 201 has a V shape in part. That is, the leg portion 431 divided in two directions is provided. The first waterproof part 201 is fitted into the gap between the holding part 281 and the seat surface 401. With the first waterproof part 201 inserted, the fixing part 241 is attached to the lens barrel 131, so that the pressing part 421 of the fixing part 241 spreads the leg part 431 (see FIG. 12), and the holding part 281 is inclined. Press against the inclined surface 411 formed on the surface and the lens barrel 131. By the pressing of the pressing portion 421, the first waterproof portion 201 is interposed between the holding portion 281 and the lens barrel 131 and the fixing portion 241, and between the first imaging lens 141 and the fixing portion 241, and the lens barrel The space between 131 and the fixing portion 241 is waterproofed.

  Even with the optical unit of the third embodiment configured as described above, the hard coat 31 can be applied continuously from the lens effective portion 26 to the holding portion 281 of the first imaging lens 141. Since the first waterproof part 201 is interposed on the surface, the first waterproof part 201 can waterproof between the first imaging lens 141 and the fixing part 241. Therefore, as in the first embodiment, the first imaging lens 141 made of resin can be applied closest to the object side while maintaining the high environmental resistance of the first imaging lens 141 for a long period of time.

  Further, according to the optical unit of the third embodiment, even when the retainer is used as the fixing portion 241, the first waterproof portion 201 is also interposed between the lens barrel 131 and the fixing portion 241. Rainwater that can enter between 131 and the fixing portion 241 can be waterproofed.

  Further, according to the optical unit of the third embodiment, since the fixing part 241 has the pressing part 421, the first waterproof part 201 is arranged between the first imaging lens 141 and the lens barrel 131 and the fixing part 241. Can be reliably introduced. Therefore, the space between the first imaging lens 141 and the fixed portion 241 and the space between the lens barrel 131 and the fixed portion 241 can be reliably waterproofed.

  Further, according to the optical unit of the third embodiment, since the cross section of the first waterproof part 201 has a V-shaped cross section at least partially, the first waterproof part 201 is replaced with the first imaging lens. 141 and the lens barrel 131 and the fixing portion 241 can be reliably introduced. Therefore, the space between the first imaging lens 141 and the fixed portion 241 and the space between the lens barrel 131 and the fixed portion 241 can be reliably waterproofed.

  Although the present invention has been described based on the drawings and embodiments, it should be noted that those skilled in the art can easily make various changes and modifications based on the present disclosure. Therefore, it should be noted that these variations and modifications are included in the scope of the present invention.

  For example, in the first embodiment and the second embodiment, the first waterproof portion 20 is the cured adhesive 35, but may be an elastic member such as an O-ring. In the second embodiment, the second waterproof portion 370 is an elastic member, but may be a cured adhesive.

  In the second embodiment, the second housing portion 25 is a groove formed on the inner peripheral surface is of the lens barrel 130, but as shown in FIG. It may be a notch formed.

  Further, in the third embodiment, the outer diameter of the holding portion 281 is shorter than the inner diameter of the seat surface 401 (see FIG. 12). However, as shown in FIG. The diameter may be increased so as to be substantially equal to the inner diameter. In the shape of the first imaging lens 141 in the third embodiment, when the convex portion 30 (see FIG. 6) protruding from the outer diameter of the holding portion 281 is formed by using a mold, the first waterproof lens 141 is used. The part 201 can be separated from the side peripheral surface of the holding part 281. When the first waterproof part 201 is separated from the outer peripheral surface of the holding part 281, the waterproofness between the first imaging lens 141 and the fixing part 241 is lowered. On the other hand, the outer periphery of the holding part 281 of the first waterproof part 201 is formed by cutting a part of the holding part 281 whose diameter is increased (see FIG. 10) and forming the convex part 30 in the cut part. It is possible to prevent separation from the surface. Further, by increasing the diameter of a part of the holding portion 281, the displacement in the direction perpendicular to the optical axis ax of the first imaging lens 141 can be restricted by the seat surface 401.

DESCRIPTION OF SYMBOLS 10, 100, 101 Image pick-up device 11, 110, 111 Optical unit 12 Image pick-up element 13, 130, 131 Lens tube 14, 141, 14 ', 14 "1st image pick-up lens 15 2nd image pick-up lens 16 3rd image pick-up lens 17 4th imaging lens 18 1st spacer 19 2nd spacer 20, 201 1st waterproof part 21 Wall part 22 Hole part 23 Object side edge part 24, 240, 241 Fixing part 25 2nd accommodating part 26 Lens effective portion 27 Inclined portion 28 Holding portion 29 First accommodating portion 30 Convex portion 31 Hard coat 32 Belt conveyor 33 Hard coat agent 34 Side peripheral surface 35 Adhesive 36 Imaging lens 370 Second waterproof portion 380 Third accommodating portion 390 Ring part 401 Seat surface 411 Inclined surface 421 Pressing part 431 Leg part ax Optical axis h Inner hole is Inner peripheral surface

Claims (13)

A lens effective portion that functions as a lens, and extends radially outward from an end portion of the lens effective portion, and an angle of a perpendicular to the optical axis of the lens effective portion is greater than an angle of a perpendicular at an end of the lens effective portion to the optical axis An inclined portion that is largely less than 90 °, a holding portion that extends radially outward of the inclined portion and includes a groove-shaped accommodation portion positioned around the inclined portion, and the lens effective portion and the inclined portion. An imaging lens having a hard coat,
A fixing unit for fixing the imaging lens in a lens barrel from a surface on the imaging target side of the holding unit;
An optical unit comprising: a first waterproof part that is accommodated in the accommodating part and waterproofs between the holding part and the fixed part .   The optical unit according to claim 1, wherein the first waterproof portion is an elastic member. The optical unit according to claim 2,
The fixing unit fixes the imaging lens by being attached to the lens barrel,
The optical unit, wherein the first waterproof part is waterproof between the lens barrel and the fixed part.   4. The optical unit according to claim 3, wherein the fixing portion includes a pressing portion that presses the first waterproof portion against the holding portion and the lens barrel when the fixing portion is attached to the lens barrel. unit.   5. The optical unit according to claim 4, wherein the first waterproof portion has a V shape in cross section.   2. The optical unit according to claim 1, wherein the first waterproof portion is a hardened adhesive.   The optical unit according to claim 6, wherein the adhesive is a thermosetting adhesive.   The optical unit according to any one of claims 1 to 7, wherein the imaging lens is formed of a resin member. The optical unit according to claim 8,
A part of the inner diameter of the lens barrel is substantially equal to the outer diameter of the holding portion, and the lens barrel is formed with a second accommodating portion that accommodates a convex portion protruding radially outward from the holding portion. An optical unit characterized by that.   10. The optical unit according to claim 9, wherein a plurality of the second accommodating portions are formed in the lens barrel. 11.   11. The optical unit according to claim 9, wherein the second housing portion is a groove formed inside the lens barrel or a notch formed at an end portion of the lens barrel. An optical unit characterized by.     12. The optical unit according to claim 1, wherein the optical unit is waterproofed between the fixing portion that fixes the imaging lens by being attached to the lens barrel and the lens barrel. An optical unit further comprising a second waterproof part. The optical unit according to any one of claims 1 to 12,
An imaging device comprising: an imaging element that captures a subject image formed through the optical unit.

Images