CN211014784U - Lens unit - Google Patents

Abstract

A lens unit includes a plurality of lenses arranged in an optical axis direction and a lens barrel for holding the plurality of lenses, wherein the plurality of lenses include glass lenses, the glass lenses are lightly pressed into a center hole of a holder held by the lens barrel, a plurality of first grooves connected to the center hole are provided at equal intervals around the center hole on one surface of the holder in the optical axis direction, a plurality of second grooves connected to the center hole are provided at equal intervals around the center hole on the other surface of the holder in the optical axis direction, the glass lenses are fixed to the holder by an adhesive applied to the plurality of first grooves and the plurality of second grooves, and a caulking portion that abuts against the glass lenses to assist in fixing the glass lenses is provided at a portion between the plurality of first grooves. The utility model discloses a glass lens among the lens unit takes place the dislocation in the optical axis direction when the lens unit can restrain when implementing thermal shock test to prevent optical property variation.

Description

Lens unit

Technical Field

The utility model relates to a lens unit.

Background

Currently, with the increase of the consumer level and the progress of science and technology, the automobile market is also developing towards multifunction and high technology. As one of the trends of automobile development, the field of automatic driving becomes a popular development direction in the automobile industry today. In automatic driving, it is necessary to accurately recognize objects in all directions, front, rear, left, and right, during the travel of a vehicle, and therefore, a higher demand is placed on the accuracy of an in-vehicle camera that is one of the recognition devices.

In order to improve the accuracy of the in-vehicle camera, a method of increasing the number of lenses in a lens unit of the camera is generally adopted. In addition, in order to improve the temperature characteristics of the camera, a glass lens is used in the lens unit. In the lens unit of the above-described in-vehicle camera including the glass lens, generally, the glass lens is bonded and fixed to a holder of the lens by an adhesive on one side in the optical axis direction, so that the glass lens is positioned and held.

However, in the above-described conventional technique in which the glass lens is adhesively fixed to the holder on only one side, when a thermal shock test in which the temperature of the lens unit is alternately changed is performed in order to improve the reliability of the in-vehicle camera (lens unit), the glass lens may be misaligned in the optical axis direction, resulting in deterioration of the optical performance of the lens unit (in-vehicle camera).

SUMMERY OF THE UTILITY MODEL

The present invention has been made in view of the above problems, and an object of the present invention is to provide a lens unit capable of suppressing the occurrence of misalignment in the optical axis direction of a glass lens in the lens unit when a thermal shock test is performed, thereby preventing deterioration of the optical performance of the lens unit.

In order to solve the above-mentioned problems, the lens unit of the present invention has a plurality of lenses arranged in the optical axis direction and a lens barrel for holding the plurality of lenses, wherein the plurality of lenses include a glass lens lightly pressed into a center hole of a holder held by the lens barrel, a plurality of first grooves connected to the center hole are provided at equal intervals around the center hole on a surface of the holder on one side in the optical axis direction, a plurality of second grooves connected to the center hole are provided at equal intervals around the center hole on the other surface of the holder in the optical axis direction, the glass lens is fixed to the holder by an adhesive applied to the plurality of first grooves and the plurality of second grooves, a caulking portion that abuts against the glass lens to assist in fixing the glass lens is provided at a portion between the plurality of first grooves.

According to the lens unit of the present invention, the plurality of first grooves and the plurality of second grooves for applying the adhesive are formed at equal intervals on both sides of the holder in the optical axis direction. Thus, compared with the case where the glass lens is adhesively fixed only on one side in the optical axis direction, by adhesively fixing the glass lens on both sides in the optical axis direction, it is possible to suppress a decrease in holding force and shrinkage of the adhesive, etc. associated with a temperature change in a thermal shock test, which causes displacement of the glass lens in the optical axis direction, to reduce variations between different combinations of the glass lens and the holder in mass production, and to prevent deterioration of the optical performance of the lens unit in actual use. Further, a caulking portion that abuts against the glass lens to assist fixing of the glass lens is provided at a portion between the plurality of first grooves. This can further suppress the occurrence of misalignment of the glass lens, thereby further preventing deterioration of the optical performance of the lens unit.

Preferably, the holder is formed with four or more first grooves.

According to the above configuration, the holder is formed with four or more first grooves. Accordingly, by positioning the glass lenses of the lens unit by bonding at four or more locations in the radial direction perpendicular to the optical axis direction of the holder, the occurrence of displacement of the glass lenses can be further suppressed, and deterioration of the optical performance of the lens unit can be further prevented.

Preferably, the holder has six first grooves, a total of three caulking portions are formed so that one caulking portion is formed every two first grooves, and a total of three press-fitting portions that come into contact with the glass lens are formed so that the caulking portions are alternately formed between the plurality of first grooves.

According to the above structure, the holder is formed with six first grooves. Accordingly, by bonding and positioning the glass lenses of the lens unit at six locations in the radial direction of the holder perpendicular to the optical axis direction, the occurrence of displacement of the glass lenses can be further suppressed, and deterioration of the optical performance of the lens unit can be further prevented. In addition, a total of three caulking portions are formed so that one caulking portion is formed every two first grooves, and a total of three press-fitting portions are formed at portions where the caulking portions are not formed between the first grooves. Thus, the three caulking portions and the press-fitting portion are fitted to each other, so that the glass lens can be further prevented from being displaced, and the optical performance of the lens unit can be further prevented from being deteriorated.

Preferably, the second groove and the press-fitting portion face each other in the optical axis direction.

According to the above configuration, the second groove faces the press-fitting portion in the optical axis direction. Thus, for example, when the glass lens is lightly pressed into the center hole of the holder from one side in the optical axis direction, even if debris or the like is generated by the press-fitting, the debris or the like is easily discharged from the second groove toward the other side in the optical axis direction, and the occurrence of displacement of the glass lens in the optical axis direction due to the debris or the like can be prevented or suppressed.

Preferably, the first and second grooves are semicircular.

According to the above structure, the first groove and the second groove are semicircular. This facilitates application of the adhesive, as compared with the case where the first groove and the second groove have a sharp shape such as a rectangular shape.

Preferably, the first groove and the second groove do not overlap in the optical axis direction.

According to the above configuration, the first groove and the second groove do not overlap in the optical axis direction, that is, the first groove and the second groove are shifted from each other in the optical axis direction. Thus, when viewed in the optical axis direction, the portion of the outer periphery of the glass lens corresponding to the caulking portion is fixed by the caulking portion, and the portions other than the portion corresponding to the caulking portion are bonded by the adhesive, so that the occurrence of misalignment of the glass lens can be further suppressed, and deterioration of the optical performance of the lens unit can be further prevented.

Preferably, the caulking portion is formed by deforming a claw portion extending in the optical axis direction from the periphery of the center hole radially inward by heat fusion.

According to the above configuration, the caulking portion is formed by deforming the claw portion extending in the optical axis direction from the periphery of the center hole radially inward by heat fusion. Thus, the glass lens can be fixed in the radial direction and the optical axis direction by the caulking portion deformed inward in the radial direction, and the occurrence of displacement of the glass lens can be further suppressed, thereby further preventing deterioration of the optical performance of the lens unit.

Preferably, the caulking portion is formed integrally with the holder.

According to the above configuration, the caulking portion is formed integrally with the holder. This reduces the number of parts of the lens unit, and contributes to improvement of the assembling property of the lens unit.

Preferably, a plurality of projections are formed on an outer periphery of a surface of the holder on one side in the optical axis direction, and the plurality of projections come into contact with a lens adjacent to the holder on one side in the optical axis direction to position the glass lens.

According to the above configuration, the plurality of projections are formed on the outer periphery of the surface of the holder on one side in the optical axis direction. This makes it possible to position the glass lens relative to the other lenses of the lens unit, and further suppress the occurrence of misalignment of the glass lens, thereby further preventing deterioration of the optical performance of the lens unit.

(effects of utility model)

According to the lens unit of the present invention, the plurality of first grooves and the plurality of second grooves for applying the adhesive are formed at equal intervals on both sides of the holder in the optical axis direction. Accordingly, by adhesively fixing the glass lenses on both sides in the optical axis direction, it is possible to suppress a decrease in holding force and shrinkage of the adhesive, which are caused by a temperature change in a thermal shock test, from causing displacement of the glass lenses in the optical axis direction, to reduce variations between different combinations of the glass lenses and the holder in mass production, and to prevent deterioration of optical performance of the lens unit in actual use. Further, a caulking portion that abuts against the glass lens to assist fixing of the glass lens is provided at a portion between the plurality of first grooves. This can further suppress the occurrence of misalignment of the glass lens, thereby further preventing deterioration of the optical performance of the lens unit.

Additional features and advantages of the lens unit described herein will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the embodiments described herein, including the detailed description which follows, the claims, as well as the appended drawings.

It is to be understood that both the foregoing general description and the following detailed description present various embodiments, and are intended to provide an overview or framework for understanding the nature and character of the claimed subject matter. The accompanying drawings are included to provide a further understanding of the various embodiments and are incorporated in and constitute a part of this specification. The drawings illustrate various embodiments described herein and together with the description serve to explain the principles and operations of the claimed subject matter.

Drawings

With reference to the above purposes, the technical features of the invention are clearly described in the claims and their advantages are apparent from the following detailed description with reference to the accompanying drawings, which illustrate by way of example a preferred embodiment of the invention, without limiting the scope of the inventive concept.

Fig. 1 is a schematic cross-sectional view showing a lens unit according to the present invention.

Fig. 2 is a schematic perspective view showing a state where the glass lens of the lens unit of the present invention is attached to the holder, as viewed from one side in the optical axis direction.

Fig. 3 is a schematic perspective view showing a state where the glass lens of the lens unit of the present invention is attached to the holder, as viewed from the other side in the optical axis direction.

(symbol description)

1 lens group

11 first lens

12 second lens

13 third lens

14 fourth lens

15 fifth lens

16 sixth lens

2 lens barrel

3 holding member

30 center hole

31 first groove

32 second groove

33 riveted part

34 press-in part

35 projection

3a front surface

3b back side

100 lens unit

Center A

Direction of optical axis F

One side of F1 in the optical axis direction

The other side of the optical axis of F2

Detailed Description

Reference will now be made in detail to various embodiments of the present invention, examples of which are illustrated in the accompanying drawings and described below. While the present invention will be described in conjunction with the exemplary embodiments, it will be appreciated that this description is not intended to limit the invention to those exemplary embodiments. On the contrary, the invention is intended to cover not only these exemplary embodiments, but also various alternatives, modifications, equivalents and other embodiments, which may be included within the spirit and scope of the invention as defined by the appended claims. For convenience in explanation and accurate definition in the appended claims, the terms "upper", "lower", "inner" and "outer" are used to describe features of the exemplary embodiments with reference to the positions of such features as displayed in the figures.

A specific configuration of the lens unit 100 of the present embodiment will be described below with reference to fig. 1 to 3. Fig. 1 is a schematic cross-sectional view showing a lens unit 100 according to the present invention, fig. 2 is a schematic perspective view showing a state where a glass lens 14 of the lens unit 100 according to the present invention is mounted on a holder 3, as viewed from one side F1, i.e., the object side, in the optical axis direction, and fig. 3 is a schematic perspective view showing a state where the glass lens 14 of the lens unit 100 according to the present invention is mounted on the holder 3, as viewed from the other side F2, i.e., the image side, in the optical axis direction.

As shown in fig. 1 to 3, a lens unit 100 of the present embodiment includes a lens group 1 and a lens barrel 2 holding the lens group 1, wherein the lens group 1 includes a plurality of lenses 11 to 16 (i.e., first to sixth lenses 11 to 16, see fig. 1) arranged in an optical axis direction F, a glass lens (fourth lens) 14, which is one of the plurality of lenses 11 to 16, is lightly press-fitted into a center hole 30 (see fig. 1 and 3) of a holder 3 held by the lens barrel 2, a plurality of first grooves 31 connected to the center hole 30 are provided around the center hole 30 on a surface (i.e., a front surface 3a, see fig. 2) of one side F1 in the optical axis direction of the holder 4, a plurality of second grooves 32 connected to the center hole 30 are provided around the center hole 30 at equal intervals on a surface (i.e., a rear surface 3b, see fig. 3) of the other side F2 in the optical axis direction of the holder 3, a plurality of second grooves 32 connected to the center hole 30 are provided around the center hole 30, the glass lens 14, a caulking portion 33 that abuts against the glass lens 14 to assist in fixing the glass lens 14 is provided at a portion between the plurality of first grooves 31.

According to the lens unit 100 of the present embodiment, the plurality of first grooves 31 and the plurality of second grooves 32 for applying the adhesive are formed at equal intervals on both sides of the holder 3 in the optical axis direction F. Thus, as compared with the case where the glass lens 14 is adhesively fixed only on one side in the optical axis direction, by adhesively fixing the glass lens 14 on both sides in the optical axis direction, it is possible to suppress the occurrence of displacement of the glass lens 14 in the optical axis direction F due to a decrease in holding force and shrinkage of the adhesive, etc. accompanying a temperature change in a thermal shock test (i.e., a test in which the lens unit is alternately subjected to a heating process and a cooling process), thereby reducing variations between different combinations of the glass lens 14 and the holder 3 in mass production, and preventing deterioration of the optical performance of the lens unit 100 in actual use. Further, a caulking portion 33 that abuts against the glass lens 14 to assist in fixing the glass lens 14 is provided at a portion between the plurality of first grooves 31. This can further suppress the occurrence of misalignment of the glass lens 14, thereby further preventing deterioration of the optical performance of the lens unit 100.

Specifically, as shown in fig. 1, in the present embodiment, the lens unit 100 is mainly configured by stacking a first lens 11, a second lens 12, a third lens 13, a fourth lens 14, a fifth lens 15, and a sixth lens 16 in the hollow portion of the lens barrel 2 in this order along the optical axis direction F. The lens unit 100 of the present embodiment is mainly applied to an in-vehicle camera, but is not limited thereto, and may be applied to a portable mobile apparatus, a home-use image pickup apparatus, a commercial image pickup apparatus, and the like.

Further, in the present embodiment, the fourth lens 14 is made of glass. Therefore, the fourth lens 14 is also sometimes referred to herein as a glass lens 14.

Hereinafter, a specific structure of the holder 3 of the lens unit 100 according to the present embodiment will be described mainly with reference to fig. 2 and 3.

In the present embodiment, the holder 3 is sandwiched between the third lens 13 and the fifth lens 15 in the lens barrel 2 so as to be substantially perpendicular to the optical axis direction F, and holds the glass lens 14 (see fig. 1). As shown in fig. 2, the holder 3 is substantially in the shape of a hollow disk having a notch in the outer periphery. An annular bump 3a1 is formed on the outer periphery of the front surface 3a, which is the surface of one side F1 in the optical axis direction of the holder 3, a plurality of protrusions 35 are formed on the bump 3a1, and the plurality of protrusions 35 and the third lens 13 (see fig. 1), which is the lens adjacent to the holder 3 on one side F1 in the optical axis direction, are brought into contact with each other to position the glass lens 14. Accordingly, the plurality of projections 35 abut against the third lens 13, so that the glass lens 4 is further prevented from being displaced, and the optical performance of the lens unit 100 is further prevented from being deteriorated.

In addition, although eight protrusions 35 are shown in fig. 2, the present invention is not limited to this, and the number of protrusions 35 may be smaller than eight or larger than eight according to actual needs.

A circular recessed portion 3a2 is formed on the inner periphery of the front surface 3a of the holder 3, and the center hole 30, the first groove 31, the caulking portion 33, and the press-fitting portion 34 are formed in the recessed portion 3a 2.

Specifically, in the present embodiment, since the glass lens 14 is substantially circular in plan view, the center hole 30 that penetrates the holder 3 in the optical axis direction F and to which the glass lens 14 is attached is also correspondingly substantially circular.

In the present invention, the holder 3 is preferably formed with four or more first grooves 31. Specifically, in the present embodiment, as shown in fig. 2, six first grooves 31 are formed in the holder 3 at equal intervals around the center hole 30, and each of the six first grooves 31 is a bottomed groove formed in the other side F2 in the optical axis direction in addition to the recessed portion 3a 1. The six first grooves 31 are formed substantially in the same substantially semicircular shape, and are connected to (communicate with) the center hole 30.

Accordingly, by positioning the glass lenses 14 of the lens unit 100 by bonding at four or more (six) locations in the radial direction perpendicular to the optical axis direction F of the holder 3, the occurrence of displacement of the glass lenses 14 can be further suppressed, and deterioration of the optical performance of the lens unit 100 can be further prevented. Further, the semicircular shape of the first groove 31 is more advantageous for application of the adhesive than the case where the first groove 31 is formed in a sharp shape such as a rectangular shape.

Although the case where the number of the first grooves 31 is four or more has been described here, the present invention is not limited to this, and the number of the first grooves 31 may be three or less, for example, as necessary.

As shown in fig. 2, the caulking portion 33 and the press-fitting portion 34 are formed in the recessed portion 3a2 at a portion where the first groove 31 is not formed. Specifically, a total of three caulking portions 33 are formed so that one caulking portion 33 is formed every two first grooves 31, and a total of three press-fitting portions 34 are formed at portions where the caulking portions 33 are not formed between the first grooves 31. That is, the caulking portion 33 or the press-fitting portion 34 is formed between the two first grooves 31 in the circumferential direction. Accordingly, the three caulking portions 33 and the press-fitting portion 34 are fitted to each other, so that the glass lens 14 is further prevented from being displaced, and the optical performance of the lens unit 100 is further prevented from being deteriorated.

More specifically, three caulking portions 33 are formed at equal intervals on the outer peripheral edge of the center hole 30. Before the glass lens 14 is caulked, the caulking portion 33 protrudes in a direction (F1) substantially parallel to the optical axis direction F. When the glass lens 14 is swaged, the swaged portion 33 is thermally melted by heating, and the tip of the swaged portion 33 is deformed inward in the radial direction of the holder 3 (i.e., toward the center a), whereby the glass lens 14 is swaged to the holder 3. That is, strictly speaking, the caulking portion 33 is formed by deforming a claw portion extending in the optical axis direction F (F1) from the periphery of the center hole 30 of the holder 3 radially inward by heat fusion. As shown in fig. 2, the deformed caulking portion 33 extends in a direction inclined with respect to the optical axis direction F (i.e., a direction between the radial direction of the holder 3 and the optical axis direction F). Accordingly, the glass lens 14 can be fixed in the radial direction and the optical axis direction F by the caulking portion 33 deformed inward in the radial direction, and the occurrence of displacement of the glass lens 14 can be further suppressed, thereby further preventing deterioration of the optical performance of the lens unit 100.

In the present embodiment, the caulking portion 33 (claw portion before thermal fusion deformation) is formed integrally with the holder 33. This reduces the number of parts of the lens unit 100, and contributes to improvement in the assembling property of the lens unit 100.

The press-fit portion 34 is a portion that assists in fixing the glass lens 14 in the radial direction of the holder 3. Specifically, the press-fitting portion 34 is a portion of the recessed portion 3a2 that is not recessed radially outward of the holder 3 to form the first groove 31 and not to form the caulking portion 33. The end of the press-fitting portion 34 close to the center a of the center hole 30 slightly protrudes radially inward than the claw portion before the rivet portion 33 is formed by thermal fusion deformation. Therefore, when the glass lens 14 is press-fitted into the center hole 30 of the holder 3, the press-fitting portion 34 is slightly deformed outward in the radial direction by the reaction force of the glass lens 14, and generates a holding force that presses the glass lens 14 inward in the radial direction.

Hereinafter, the structure of the back surface 3b of the holder 3, particularly the structure of the second groove 32, will be described mainly with reference to fig. 3.

As shown in fig. 3, three second grooves 32 are formed at equal intervals on the back surface 3b of the holder 3 near the inner periphery of the center hole 30. Each of the three second grooves 32 is a bottomed groove formed in the rear surface 3b of the holder 3 so as to be recessed toward one side F1 in the optical axis direction. Further, the three second grooves 32 are formed substantially in the same substantially semicircular shape, respectively, and are all connected to (communicated with) the center hole 30. Thus, the semicircular shape of the second groove 32 is more advantageous for application of the adhesive than when the second groove 32 is formed in a sharp shape such as a rectangular shape.

Although the case where the number of the second grooves 32 is three has been described here, the present invention is not limited to this, and the number of the second grooves 32 may be set according to the number of the first grooves 31.

As is clear from fig. 2 and 3, the second groove 32 and the press-fitting portion 34 are opposed to each other in the optical axis direction F, that is, the second groove 32 and the caulking portion 33 are shifted from each other. Accordingly, for example, when the glass lens 14 is lightly pressed into the center hole 30 of the holder 3 from one side F1 in the optical axis direction, even if debris or the like is generated by the press-fitting, the debris or the like is easily discharged from the second groove 32 toward the other side F2 in the optical axis direction, and the occurrence of displacement of the glass lens 14 in the optical axis direction F due to the debris or the like can be prevented or suppressed.

In other words, in the present embodiment, the first groove 31 and the second groove 32 do not overlap in the optical axis direction F, that is, the first groove 31 and the second groove 32 are shifted from each other in the optical axis direction F. Accordingly, when viewed in the optical axis direction F, the portion of the outer periphery of the glass lens 14 corresponding to the caulking portion 33 is fixed by the caulking portion 33, and the portions other than the portion corresponding to the caulking portion 33 are bonded by the adhesive, so that the occurrence of displacement of the glass lens 14 can be further suppressed, and deterioration of the optical performance of the lens unit 100 can be further prevented.

Although the case where the front surface 3a of the holder 3 faces the object side (i.e., F1) and the back surface 3b faces the image side (F2) has been described above, the present invention is not limited thereto. For example, the structure of the holder 3 may be appropriately changed so that the front surface 3a of the holder 3 and the structures formed thereon (the first groove 31, the caulking portion 33, the press-fitting portion 34, and the like) face the image side (i.e., F2) and the back surface 3b and the structures formed thereon (the second groove 32, and the like) face the object side (F1).

The steps of the mounting process of the glass lens 14 and the holder 3 will be briefly described below.

First, the glass lens 14 is lightly pressed into the center hole 30 of the holder 3, so that the press-fitting portion 34 is slightly deformed to come into contact with the glass lens 14 in the radial direction.

Then, an adhesive is applied to the six first grooves 31 and the three second grooves 32, respectively, to bond the glass lens 14 to the holder 3.

Next, the claw portion for forming the caulking portion 33 is thermally melted by heating, so that the tip end of the claw portion is deformed toward the inside in the radial direction of the holder 3 (i.e., toward the center a) to form the caulking portion 33, to thereby caulk the glass lens 14 to the holder 3.

After that, the glass lens 14 and the holder 3 after the mounting are subjected to a heating process and a cooling process (i.e., thermal shock).

Finally, the glass lens 14 and the holder 3 after the heating treatment and the cooling treatment are mounted in the hollow portion of the lens barrel 2 of the lens unit 100.

The present invention can freely combine the embodiments within the scope thereof, or appropriately modify or omit the embodiments.

Claims (9)

1. A lens unit having a plurality of lenses arranged in an optical axis direction and a lens barrel holding the plurality of lenses,

the plurality of lenses include a glass lens lightly pressed into a center hole of a holder held by the lens barrel,

a plurality of first grooves connected to the center hole are provided at equal intervals around the center hole on a surface of the holder on one side in the optical axis direction,

a plurality of second grooves connected to the center hole are provided at equal intervals around the center hole on the other surface of the holder in the optical axis direction,

the glass lens is fixed to the holder by an adhesive applied to the plurality of first grooves and the plurality of second grooves,

a caulking portion that abuts against the glass lens to assist in fixing the glass lens is provided at a portion between the plurality of first grooves.

2. The lens unit of claim 1,

the holder is formed with four or more of the first grooves.

3. The lens unit of claim 1,

the holder is formed with six of the first grooves,

a total of three of the caulking portions are formed so that one caulking portion is formed every two of the first grooves,

a total of three press-fitting portions that come into contact with the glass lens are formed so as to be alternately formed between the plurality of first grooves and the caulking portions.

4. The lens unit of claim 3,

the second groove faces the press-fitting portion in the optical axis direction.

5. The lens unit of claim 1,

the first groove and the second groove are semicircular.

6. The lens unit of claim 1,

the first groove and the second groove do not overlap in the optical axis direction.

7. The lens unit of claim 1,

the caulking portion is formed by deforming a claw portion extending in the optical axis direction from the periphery of the center hole radially inward by heat fusion.

8. The lens unit of claim 1,

the rivet is formed integrally with the holder.

9. The lens unit of any of claims 1-8,

a plurality of projections are formed on the outer periphery of one surface of the holder in the optical axis direction,

the plurality of projections abut on the lens adjacent to the holder on one side in the optical axis direction to position the glass lens.

Images