JP2018194594A - Lens unit and camera module - Google Patents

Abstract

To provide a lens unit capable of suppressing degradation of a barrel, and a camera module having the lens unit.SOLUTION: A lens unit 1 includes a lens and a resin barrel 3 supporting the lens. The barrel 3 has an ultraviolet cut film 6a formed in a portion exposed to outdoor environment in use. Accordingly, it is possible to suppress degradation of the barrel 3 in the lens unit 1 and a camera module having the lens unit 1.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a lens unit and a camera module including the lens unit.

  In recent years, an in-vehicle camera is mounted on an automobile to support parking or to prevent a collision by image recognition, and an application to automatic driving has been attempted. In a lens unit used for such an in-vehicle camera, a part of the lens unit is exposed outside the vehicle, and the exposed part may be exposed to an outdoor environment. At this time, the exposed portion is irradiated with ultraviolet rays.

  The lens unit includes a lens and a barrel that supports the lens. In addition, since the lens on the most object side in the lens unit has a surface on the object side exposed to the outside, a water repellent film having water repellency is formed on this surface, so that the lens has a water repellency function. There is (for example, Patent Document 1). On the other hand, conventionally, the barrel is not subjected to a film treatment for forming a film.

Japanese Patent Laid-Open No. 2006-65954

  By the way, when the barrel is made of resin, a portion of the barrel exposed to the outdoor environment may be whitened or fuzzy due to the influence of ultraviolet rays. In addition, the strength of the barrel may drop due to the influence of ultraviolet rays. As described above, when the barrel is irradiated with ultraviolet rays, the portion irradiated with the ultraviolet rays may deteriorate.

  The present invention has been made in view of the above circumstances, and an object thereof is to provide a lens unit that can suppress barrel deterioration and a camera module including the lens unit.

  In order to solve the above problems, a lens unit of the present invention is a lens unit including a lens and a resin barrel that supports the lens, and the barrel is exposed to an outdoor environment during use. In addition, an ultraviolet cut film is formed.

  According to such a structure, since the ultraviolet cut film is formed in the barrel at the portion exposed to the outdoor environment, the amount of ultraviolet rays reaching the barrel can be reduced. Therefore, deterioration of the barrel due to the influence of ultraviolet rays can be suppressed.

  Moreover, in the said structure of this invention, it is preferable that the water-repellent film is formed on the said ultraviolet cut film.

  According to such a configuration, since the water-repellent film is formed on the ultraviolet cut film, the deterioration of the barrel due to moisture (humidity) can be suppressed. In addition, when the lens has a water repellent function and the barrel does not have a water repellent function, water that has flowed on the lens surface may not flow on the barrel surface, and water may accumulate on the barrel surface. However, in this configuration, since the water repellent film is formed on the ultraviolet cut film, the water repellent film can improve the flow of water and prevent water from accumulating on the barrel surface.

In addition, the camera module of the present invention includes the lens unit having the above-described configuration, and further includes an imaging element that captures an image formed by the lens unit having the above-described configuration.
According to such a configuration, the camera module can achieve the same effects as the lens unit described above.

  According to the present invention, deterioration of the barrel can be suppressed.

It is a figure which shows the 1st Embodiment of this invention, Comprising: It is the figure which combined the half sectional view of the lens unit, and sectional drawing of a case. FIG. 2 is an enlarged view of a portion X surrounded by a dashed line in FIG. It is a figure which shows the 2nd Embodiment of this invention, Comprising: It is the figure which combined the one-side sectional view of the lens unit, and sectional drawing of a case. It is a figure which shows the 3rd Embodiment of this invention, Comprising: It is a half sectional view of a lens unit.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
FIG. 1 shows a lens unit 1 according to a first embodiment and a case 2 that covers the lens unit 1 with the object side (imaging target side) of the lens unit 1 exposed to the outside. FIG. 5 is a diagram in which a sectional view of one side of the lens unit 1 and a sectional view of the case 2 are combined. In FIG. 1, members such as a lens housed inside the lens unit 1 are not shown.

Although the lens unit 1 of this Embodiment is used for a vehicle-mounted camera, it is not limited to a vehicle-mounted camera, It can also be used for a surveillance camera and another camera.
The lens unit 1 constitutes a camera module together with an image sensor, a wiring board, a signal processing circuit, a flexible wiring sheet, a connector, and the like. The camera module refers to a camera module including at least a lens unit and an image sensor. The camera module according to the present embodiment includes an image sensor 20 disposed on the image forming side of the lens unit 1 (the side on which the lens unit 1 connects images) and a substrate 21 having the image sensor 20. It is possible to take an image formed with the.

The lens unit 1 includes a cylindrical barrel 3 (lens barrel) and a plurality of lenses (not shown). The plurality of lenses are housed inside the barrel 3 and supported by the barrel 3 with their optical axes aligned. Further, these optical axes and the axis of the barrel 3 are in agreement. Note that other optical components such as a diaphragm and a spacer may be housed inside the barrel 3.
FIG. 1 shows the object-side surface (lens surface 4) of the most object-side lens among the plurality of lenses.

  The barrel 3 is formed of a synthetic resin. Specifically, Zylon (registered trademark) in which a special filler for improving dimensional accuracy is blended with modified polyphenylene ether resin, Reny (registered trademark) in which polyamide resin is blended with glass fiber and inorganic filler to increase rigidity. ) And the like.

  In the barrel 3, the end 3a on the object side is caulked with heat. Further, the barrel 3 includes a locking portion 3b formed at the end on the image forming side so as to protrude inward so that the inner diameter becomes small. The optical component including the plurality of lenses housed inside the barrel 3 is locked to the end 3 a including the heat caulking portion and the locking portion 3 b and supported by the barrel 3. An opening is formed inside the crimped end portion 3 a of the barrel 3, and the lens surface 4 is exposed to the outside of the barrel 3 from this opening.

  The case 2 has an opening 5 for exposing the end of the lens unit 1 on the object side to the outside of the case 2. The lens unit 1 is in a state in which the end on the object side is exposed from the opening 5 to the outside of the case 2 and the other part is covered with the case 2. Specifically, in the lens unit 1, the end 3 a on the object side of the barrel 3 and the lens surface 4 are exposed to the outside of the case 2.

  When used as a vehicle-mounted camera, the lens unit 1 is directly or indirectly attached to the case 2 and is provided in the vehicle in an integrated state with the case 2. At this time, a part of the outer surface 2a of the case 2, the end 3a of the barrel 3, and the lens surface 4 are exposed to the outside of the vehicle and are exposed to the outdoor environment (wind and rain). Yes.

  A water repellent film (not shown) is formed on the surface of the lens surface 4. That is, of the optical components housed in the barrel 3 of the lens unit 1, the portion exposed to the outdoor environment of the optical components exposed to the outdoor environment is covered with a water repellent film. .

A thin film portion 6 is provided on the outer surface of the barrel 3. As shown in FIG. 2, the thin film portion 6 includes an ultraviolet cut film 6a and a water repellent film 6b.
2 is an enlarged view of a portion X surrounded by a one-dot chain line in FIG.

The ultraviolet cut film 6a and the water repellent film 6b are formed on the outer surface (surface) of the barrel 3 in this order. That is, the outer surface of the barrel 3 is coated with an ultraviolet cut film 6a (ultraviolet cut coating), and further coated with a water repellent film 6b (water repellent coating) on the ultraviolet cut film 6a.
As a method for forming the ultraviolet cut film 6a and the water repellent film 6b on the plastic surface, there are a dry coating method by vapor deposition or sputtering and a wet coating method in which a coating liquid such as ink or paint is applied. For the ultraviolet cut film 6a and the water repellent film 6b, first, the ultraviolet cut film 6a is formed on the barrel 3 by a dry coating method or a wet coating method, and then the water repellent film 6b is formed by a dry coating method or a wet coating method. Is formed. Here, the method for forming the ultraviolet cut film 6a and the water repellent film 6b may be determined according to the material of each film. Moreover, you may form by methods other than these. 1 to 4 show the thin film portion 6 (ultraviolet cut film 6a and water repellent film 6b) with emphasis, but in actuality, the thickness may be, for example, 0.1 μm or less. .

  The ultraviolet cut film 6a is a thin film having a function of cutting ultraviolet rays. The ultraviolet cut film 6a refers to a film that cuts 70% or more of the ultraviolet rays having a wavelength of 280 nm to 380 nm at least.

  The water repellent film 6b is a thin film having water repellency. Here, the water repellent film 6b has a contact angle of water drops with respect to the water repellent film of 80 degrees or more. Specifically, the water repellent film 6b is, for example, a thin film made of a fluororesin. The water repellent film 6b may be formed of a material other than the fluororesin as long as it has water repellency.

As described above, when the outer surface of the barrel 3 is irradiated with ultraviolet rays, the barrel 3 may be deteriorated. Specifically, when the barrel 3 is whitened, the appearance of the lens unit 1 is deteriorated. Further, when the barrel 3 becomes fluffy, not only does it look bad, but there is also a possibility that the fluffy part will be reflected during imaging. In particular, when the lens unit 1 has a wide angle, the possibility that a fuzzy portion is reflected is increased. In addition, this fluff is mainly generated when the filler added to the resin comes out on the surface.
Moreover, if the intensity | strength of the barrel 3 falls with an ultraviolet-ray, the lens unit 1 will become easy to break.

  In the present embodiment, the resin barrel 3 is formed with an ultraviolet cut film 6a on a portion exposed to the outdoor environment in a state where the resin barrel 3 is provided, so that the amount of ultraviolet rays reaching the outer surface of the barrel 3 is increased. Can be reduced. Therefore, deterioration of the barrel 3 due to the influence of ultraviolet rays can be suppressed. In addition, although it does not specifically limit about the material of the ultraviolet cut film 6a, For example, you may use what mix | blended the ultraviolet absorber. As ultraviolet absorbing materials, benzotriazole-based or benzophenone-based organic absorbents are widely used for the purpose of improving the weather resistance of resin molded articles and coating films. In particular, zinc oxide, titanium oxide, tungsten trioxide, and strontium titanate are suitable as the ultraviolet absorbing material.

  Further, since the water repellent film 6b is formed on the ultraviolet cut film 6a, the deterioration of the barrel 3 due to moisture (humidity) can be suppressed. A water repellent film is also formed on the surface of the lens surface 4. Therefore, for example, when the lens unit 1 is exposed to rain, water can easily flow from the surface of the lens surface 4 and the surface of the barrel 3. Therefore, water can be prevented from accumulating on the surface of the barrel.

  Further, since the water repellent film 6b is formed on the ultraviolet cut film 6a, the water resistance of the ultraviolet cut film 6a can be improved. Further, since the water repellent film 6b eliminates the direct influence of moisture on the ultraviolet cut film 6a, the ultraviolet cut film 6a can be made difficult to peel off.

The ultraviolet cut film 6 a and the water repellent film 6 b may not be formed on the entire outer surface of the barrel 3. That is, the ultraviolet cut film 6 a and the water repellent film 6 b may be formed on the barrel 3 at a portion exposed to the outside of the case 2.
The ultraviolet cut film 6 a and the water repellent film 6 b may also be formed on the inner surface of the barrel 3. In particular, since the fluororesin water-repellent film 6b and the like have a low coefficient of friction and high slipperiness, such a thin film is formed on the inner surface of the barrel 3 to insert an optical component inside the barrel 3. The optical component can be smoothly inserted.
Further, instead of the water repellent film 6 b formed on the surface of the lens surface 4 or the outer surface of the barrel 3, a hydrophilic film having hydrophilicity may be formed.

(Second Embodiment)
FIG. 3 shows a lens unit 1 according to the second embodiment, and a case 2 that covers the lens unit 1 with the object side (imaging target side) of the lens unit 1 exposed to the outside. FIG. 5 is a diagram in which a sectional view of one side of the lens unit 1 and a sectional view of the case 2 are combined. In FIG. 3, members such as a lens housed inside the lens unit 1 are omitted.
Since the lens unit 1 of the present embodiment is mainly different from the lens unit 1 of the first embodiment in the configuration of the barrel 3, this point will be described below, and the first embodiment and the first embodiment will be described. The same components are denoted by the same reference numerals, and the description thereof is omitted or simplified.

The barrel 3 includes a cylindrical barrel body 10 and a cylindrical pressing member 11.
A male screw portion 10 a is formed on the outer peripheral surface of the end portion on the object side of the barrel body 10. Further, the barrel main body 10 includes a locking portion 3a formed at the end on the image forming side so as to protrude inward so that the inner diameter becomes small. An internal thread portion 11a is formed on the inner peripheral surface of the end portion of the pressing member 11 on the image forming side. In addition, the pressing member 11 includes a locking portion 11b formed at the end on the object side so as to protrude inward so as to reduce the inner diameter.

  The holding member 11 is fixed to the barrel main body 10 by the female screw portion 11 a being screwed into the male screw portion 10 a of the barrel main body 10. The optical component including the plurality of lenses housed inside the barrel 3 is locked by the locking portion 3 a and the locking portion 11 b and supported by the barrel 3. Further, an opening is formed inside the locking portion 11b, and the lens surface 4 is exposed to the outside of the barrel 3 from the opening.

  In the lens unit 1, the end of the holding member 11 on the object side and the lens surface 4 are exposed to the outside of the case 2. That is, when used as a vehicle-mounted camera, a part of the outer surface 2a of the case 2, the end of the pressing member 11 on the object side, and the lens surface 4 are in a state exposed to the outside of the vehicle. You are exposed to the environment.

On the outer surface of the pressing member 11, a thin film portion 6 including an ultraviolet cut film 6a and a water repellent film 6b is provided. That is, in the present embodiment, the ultraviolet cut film 6a and the water repellent film 6b are formed on the pressing member 11 which is a member exposed to the outdoor environment among the members constituting the barrel 3. Therefore, also in this embodiment, it is possible to obtain the same effect as that of the first embodiment.
The ultraviolet cut film 6 a and / or the water repellent film 6 b may be formed on the outer surface of the barrel body 10, or may be formed on the inner surface of the barrel body 10 and / or the inner surface of the pressing member 11. .

(Third embodiment)
FIG. 4 is a half sectional view of the lens unit 1 according to the third embodiment. In FIG. 4, members such as a lens housed inside the lens unit 1 are omitted.
Since the lens unit 1 of the present embodiment is mainly different from the lens unit 1 of the first embodiment in the configuration of the barrel 3, this point will be described below, and the first embodiment and the first embodiment will be described. The same components are denoted by the same reference numerals, and the description thereof is omitted or simplified.

  In the lens unit 1 of the present embodiment, the barrel 3 and the case 2 are integrally formed, and an integrated barrel 15 is formed. That is, the integrated barrel 15 is a barrel 3 that also serves as the case 2.

  In the integrated barrel 15, the barrel 3 and the case 2 in the first embodiment are in an integrated state. The integral barrel 15 is formed of Zylon (registered trademark), Reny (registered trademark), or the like. Further, on the outer surface of the integral barrel 15, a thin film portion 6 including an ultraviolet cut film 6 a and a water repellent film 6 b is provided.

Since the integrated barrel 15 also serves as the case 2, when the lens unit 1 is used as an in-vehicle camera, a part of the outer surface of the integrated barrel 15 and the lens surface 4 are exposed outside the vehicle. It is in a state exposed to the outdoor environment. In the present embodiment, since the ultraviolet cut film 6a and the water repellent film 6b are formed on the outer surface of the integrated barrel 15, the same operational effects as those of the first embodiment can be obtained.
The ultraviolet cut film 6a and the water repellent film 6b may be formed on the outer surface of the integrated barrel 15 when the lens unit 1 is provided in a car or the like and exposed to the outdoor environment when used. Good.

DESCRIPTION OF SYMBOLS 1 Lens unit 2 Case 3 Barrel 6a Ultraviolet cut film 6b Water-repellent film 15 Integrated barrel 20 Imaging element

Claims (3)

A lens unit comprising a lens and a resin barrel supporting the lens,
The lens unit is characterized in that an ultraviolet cut film is formed on a portion of the barrel exposed to an outdoor environment during use.   The lens unit according to claim 1, wherein a water repellent film is formed on the ultraviolet cut film.   A camera module comprising the lens unit according to claim 1, and further comprising an imaging device that captures an image formed by the lens unit.

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