JP2021036291A - Camera device - Google Patents

Abstract

To provide a camera device capable of preventing adhesion of water droplets to a lens exposed to outside air.SOLUTION: A camera device is provided, comprising a lens 3 exposed to outside air and a lens barrel 2 having a flange 21 covering the outer edge of the lens 3. A surface treatment film 26 is formed on a front surface of the flange 21, the surface treatment film 26 being formed by alumite treatment.SELECTED DRAWING: Figure 2

Description

The present invention relates to, for example, a camera device mounted on a vehicle.

For example, a camera device mounted on a vehicle continuously photographs the surroundings of the vehicle such as the front and the rear of the vehicle in time and records an image. The camera device is attached to the inside or outside of the vehicle, but the camera device provided outside the vehicle is exposed to the external environment such as wind and rain.

In Patent Document 1, a first elastic sealing member is provided between a first stage portion of a lens barrel that houses and supports a first lens and an end portion of the first lens, and an end face of the second lens is also provided. A camera device provided with a second elastic sealing member that prevents the penetration of moisture from the inside of the camera is disclosed.

Further, Patent Document 2 describes a lens barrel, a lens in which a part of a front convex surface protruding forward from the lens barrel is held, and an annular pressing member fixed to the lens barrel and fixed to the lens. The camera device provided is disclosed. The pressing member has a groove formed on the front surface from the inner peripheral end to the outer peripheral end.

Japanese Unexamined Patent Publication No. 2005-250348 JP-A-2007-316167

In the camera device described in Patent Document 1, the first and second elastic sealings can be sealed to suppress the occurrence of dew condensation or fogging inside the lens, but the fact that water droplets due to rainwater falling from the outside adhere to the lens or the like. Is not considered. In particular, in an infrared camera device, if water droplets adhere to a lens exposed to the outside air, there is a problem that the transmission of infrared rays is hindered and the camera performance is significantly deteriorated.

In the camera device described in Patent Document 2, the groove formed in the holding member serves as a passage for discharging water, but discharge of water droplets adhering to the groove portion and the convex portion between the grooves is promoted. It wasn't done.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a camera device capable of suppressing adhesion of water droplets to a lens exposed to the outside air.

A camera device according to an aspect of the present invention is a camera device including a lens exposed to the outside air and a lens barrel having a flange covering the outer edge of the lens, in which a surface treatment film is formed on the front surface of the flange. The surface-treated film is characterized in that it is formed by alumite treatment.

A camera device of another aspect of the present invention is a camera device including a lens exposed to the outside air and a lens barrel having a flange covering the outer edge of the lens, in which a surface treatment film is provided on the front surface of the flange. It is characterized in that the contact angle formed by the outer surface of the water droplets adhering to the surface treatment film and the surface is 60 deg or more and 80 deg or less.

According to the present invention, the camera device can suppress the adhesion of water droplets to the lens exposed to the outside air.

It is a perspective view which shows the appearance of the camera apparatus which concerns on Embodiment 1. FIG. It is sectional drawing of the front end part of a camera device. It is sectional drawing of the flange part. It is a schematic diagram for demonstrating the water drop adhering to the surface of a flange. It is a figure which shows the contact angle of the water droplet measured for each surface treatment of a flange. FIG. 6 (a) is a schematic view for explaining the flow of water on the surface of the lens and the flange in the present embodiment, and FIG. 6 (b) shows the flow of water on the surface of the lens and the flange in the comparative example. It is a schematic diagram for demonstrating. It is sectional drawing of the flange part which concerns on the modification.

Hereinafter, the present invention will be described with reference to FIGS. 1 to 7 based on a preferred embodiment. The same or equivalent components and members shown in the drawings shall be designated by the same reference numerals, and redundant description will be omitted as appropriate. In addition, the dimensions of the members in each drawing are shown enlarged or reduced as appropriate for easy understanding. In addition, some of the members that are not important for explaining the embodiment in each drawing are omitted and displayed.

(Embodiment 1)
FIG. 1 is a perspective view showing the appearance of the camera device 100 according to the first embodiment. The camera device 100 includes a camera body 1, a lens barrel 2, a lens 3, and the like. The camera body 1 has a box shape provided with a hole leading to the inside of the lens barrel 2, and houses a detector, a filter, and the like (not shown) inside. The lens barrel 2 has a tubular shape and supports an optical system arranged inside, and a lens 3 is fitted in an opening 2a on the front surface. The lens barrel 2 has a frame portion 20 for holding the lens 3. The lens 3 is, for example, an aspherical lens, but the lens 3 is not limited to this and may be a spherical lens or the like. Further, the camera device 100 is, for example, an infrared camera, but is not limited to this, and may be a visible light imaging camera or the like.

FIG. 2 is a cross-sectional view of the front end portion of the camera device 100. The front surface of the lens 3 is exposed to the outside air, and the lens 3 is exposed to an external environment such as wind and rain. The outer edge portion of the lens 3 exposed to the outside air on the front surface side is covered with the flange 21 of the frame portion 20 of the lens barrel 2. The lens barrel 2 is provided with a frame portion 20 for holding the lens 3 so as to be fitted inside the opening hole on the front end side, but the frame portion 20 and the lens barrel 2 are integrally formed. May be good.

The frame portion 20 of the lens barrel 2 has a flange 21 that covers the outer edge portion on the surface side of the lens 3, and the light-shielding portion 23 is formed on the inner peripheral portion of the inner edge portion 22. The light-shielding portion 23 has a tapered shape that is inclined with respect to the optical axis direction, and has a larger diameter toward the front end. The light-shielding portion 23 functions to block infrared rays or light rays from an angle larger than the taper angle.

An inclined portion 24 is formed on the inner edge portion 22 of the flange 21 so as to be continuous with the outer peripheral portion of the light-shielding portion 23. The inclined portion 24 has a tapered shape that increases in diameter toward the front end. As shown in FIG. 2, the taper angle A of the inclined portion 24 is larger than the taper angle of the light-shielding portion 23, and more specifically, it is set to 120 degrees or more. Further, the taper angle A of the inclined portion 24 is preferably set to 160 degrees or less.

The flange 21 has a front end surface 25 that is continuous with the outer peripheral portion of the inclined portion 24 and extends outward. The thickness t of the flange 21 on the front end surface 25 is set so as to have sufficient strength and rigidity to hold the lens 3. The thickness of the flange 21 is thinner at the light-shielding portion 23 and the inclined portion 24 than at the thickness t of the front end surface 25. When the thickness of the light-shielding portion 23, the inclined portion 24, and the front end surface 25 becomes thin, the rigidity is lowered and deformed, the strength is lowered and cracks occur, and the manufacturability is further deteriorated.

The inclined portion 24 and the front end surface 25 of the flange 21 shown in FIG. 2 are formed at substantially the front end of the lens barrel 2, but may be formed at a position recessed one step toward the camera body 1 side, or conversely, the front side. It may be formed at a position protruding one step. Further, the connection portion between the light-shielding portion 23 and the inclined portion 24 and the connection portion between the inclined portion 24 and the front end surface 25 may have corners or may be rounded and smoothly connected.

The lens 3 has a concave surface portion 3a in which the surface side exposed to the outside air is concave with respect to the front inside the light shielding portion 23 corresponding to the outer edge portion. The lens 3 has a convex surface portion 3b that is convex with respect to the front inside the concave surface portion 3a. The lens 3 shown in FIG. 2 is formed as an aspherical lens. Further, as described above, the lens 3 may be a spherical lens or the like, and in this case, the concave surface portion 3a may not be formed.

FIG. 3 is a cross-sectional view of the flange 21 portion. A surface treatment film 26 is formed on the surface of the light-shielding portion 23, the inclined portion 24, and the front end surface 25 that are exposed to the outside air. Further, the surface treatment film 26 may also be formed on the front end surface of the lens barrel 2 which is continuous with the outer edge portion of the front end surface 25. The flange 21 is made of an aluminum material, and the surface treatment film 26 is formed by a black alumite treatment.

When water droplets adhere to the light-shielding portion 23, the inclined portion 24, and the front end surface 25 due to rainfall, the adhered water droplets become resistance, and the flow velocity of the wind flowing outward from the center of the lens 3 as shown by arrow P in FIG. descend. A surface treatment film 26 is formed so that water droplets adhering to the light-shielding portion 23, the inclined portion 24, and the front end surface 25 easily flow to the outside and are easily discharged and do not stay.

In the alumite treatment, an oxide film having a porous layer in which fine pores are formed is formed by the anodizing treatment. The porous layer provides adhesion for adhesion, adhesion and painting. In the state of entering the porous layer, a coating film colored in silver, bronze, black, white or the like is generated, so that the coating film is difficult to peel off.

Further, by depositing the resin paint on the surface of the porous layer by using a method such as electrodeposition coating, it is possible to obtain a glossy, matte or white surface. Further, before the alumite treatment, a blasting treatment may be performed in which the surface is roughened by blasting with small-diameter particles.

FIG. 4 is a schematic view for explaining water droplets adhering to the surface of the flange 21. The water droplets adhering to the surface of the flange 21 become hemispherical with the central portion raised by surface tension. When the water repellency of the surface of the flange 21 is low, the water droplets tend to be flatter and difficult to flow, and when the water repellency is high, the height of the water droplets tends to be high and the water droplets tend to flow easily. Further, when the water repellency on the surface of the flange 21 is very high and the water droplets are in a state close to a spherical shape, it is necessary to directly act on the water droplets with a force that opposes the weight of the water droplets in order to discharge the water droplets by the wind. , It is thought that it will be difficult to flow. Therefore, in order to facilitate the removal of water droplets adhering to the surface of the flange 21, the water repellency of the surface of the flange 21 is required to be optimized.

Assuming that the height of the apex of the water droplet is h and the diameter of the bottom surface of the water droplet is 2r, the contact angle θ formed by the adhered surface and the outer surface of the water droplet is
θ = 2 θ ₁ = 2 tan ^-1 (h / r) ・ ・ ・ (1)
It is expressed as. Here, the contact angle is calculated by the θ / 2 method.

When the water repellency of the surface of the flange 21 is low, the diameter 2r of the bottom surface of the water droplet is large, the height h is low, and the contact angle θ is small. Further, when the water repellency of the surface of the flange 21 is high, the diameter 2r of the bottom surface of the water droplet is small, the height h is high, and the contact angle θ is large.

FIG. 5 is a chart showing the contact angles of water droplets actually measured for each surface treatment of the flange 21. The contact angle of each example shown in FIG. 5 is calculated by the above equation (1). On the surface of the flange 21 treated with matte black alumite, the contact angle of water droplets is 63 to 65 deg, and on the surface of the flange 21 treated with matte black alumite after blasting, the contact angle of water droplets is It was 64-66 deg.

Further, on the surface of the flange 21 on which the surface treatment film of the texture coating was formed, the contact angle of water droplets was 73 to 75 deg. Further, on the surface of the flange 21 treated with glossy black alumite, the contact angle of water droplets was 78 to 80 deg.

FIG. 6A is a schematic view for explaining the flow of water on the surfaces of the lens 3 and the flange 21 in the present embodiment, and FIG. 6B is a schematic view on the surface of the lens 3 and the flange 21 in the comparative example. It is a schematic diagram for demonstrating the flow of water. For comparison, FIG. 6B describes a case where the water droplet has a spherical shape and a case where the contact angle is small.

As shown in FIG. 6A, a surface-treated film 26 such as alumite treatment and grain coating is formed on the flange 21 in the present embodiment, and the contact angle of the adhered water droplets is 60 deg or more and 80 deg or less. ing. As a result, in the camera device 100, the flow of water droplets becomes good at the light-shielding portion 23, the inclined portion 24, and the front end surface 25 of the flange 21, and the water droplets are easily discharged to the outside by the wind indicated by the arrow P in the drawing, and the flow velocity of the wind. The decrease is suppressed. By suppressing the decrease in the flow velocity of the wind, the water adhering to the lens 3 is promoted to be discharged from the outer edge portion of the lens 3 to the flange 21, and the adhering of water to the lens 3 is suppressed.

Further, the contact angle of water droplets is 70 deg or more and 80 deg or less on the surface of the flange 21 on which the surface-treated film 26 coated with grain and the surface-treated film 26 treated with glossy black alumite are formed, and the water droplets are outside due to the wind. By eliminating water droplets on the surface of the flange 21, the decrease in the flow velocity of the wind is further suppressed. Since the contact angle of the water droplets on the surface of the flange 21 is an angle that is easily discharged by the wind flowing outward from the center of the lens 3, adhesion of the water droplets to the lens is suppressed.

On the other hand, as shown in FIG. 6B, when the contact angle of the water droplets adhering to the surface of the flange 21 is small, it becomes difficult for the water droplets to be discharged to the outside at the light-shielding portion 23, the inclined portion 24 and the front end surface 25. The flow velocity of the wind decreases, and water stays at the outer edge of the lens 3 and the like. Further, when the water droplet becomes a state close to a sphere, it becomes necessary for the wind to directly act on the water droplet with a force that opposes the weight of the water droplet, so that the water droplet becomes difficult to flow, the flow velocity of the wind decreases, and the water flows into the lens 3. It stays on the outer edge of the lens.

(Modification example)
FIG. 7 is a cross-sectional view of the flange 21 portion according to the modified example. In the modified example, an annular light-shielding member 27 is provided on the inner edge of the flange 21. The light-shielding portion 23 of the light-shielding member 27 and the inclined portion 24 and the front end surface 25 of the flange 21 may form different surface-treated films 26.

For example, the light-shielding portion 23 may be a texture-coated surface-treated film 26, a matte black alumite-treated surface-treated film 26, or a blast-treated and then matte black alumite-treated surface-treated film 26. , Suppresses the entry of stray light into the camera device 100. On the other hand, by forming the inclined portion 24 and the front end surface 25 of the flange 21 into a surface-treated film 26 by a glossy black alumite treatment, adhesion of water droplets is suppressed.

Next, the features of the camera device 100 according to each of the above-described embodiments will be described.
The camera device 100 according to the embodiment includes a lens 3 exposed to the outside air and a lens barrel 2 having a flange 21 covering the outer edge of the lens 3. A surface treatment film 26 is formed on the front surface of the flange 21, and the surface treatment film 26 is formed by an alumite treatment. As a result, in the camera device 100, water droplets on the surface of the flange 21 are easily discharged by the wind, a decrease in the flow velocity of the wind is suppressed, and adhesion of the water droplets on the lens 3 is suppressed.

The surface treatment film 26 is formed by a glossy alumite treatment. As a result, in the camera device 100, water droplets on the surface of the flange 21 are more easily discharged, a decrease in the flow velocity of the wind is suppressed, and adhesion of water droplets on the lens 3 is further suppressed.

The camera device 100 includes a lens 3 exposed to the outside air and a lens barrel 2 having a flange 21 covering the outer edge of the lens 3. A surface treatment film 26 is formed on the front surface of the flange 21, and the contact angle between the outer surface of the water droplets adhering to the surface treatment film 26 and the surface is 60 deg or more and 80 deg or less. As a result, in the camera device 100, water droplets on the surface of the flange 21 are easily discharged by the wind, a decrease in the flow velocity of the wind is suppressed, and adhesion of the water droplets on the lens 3 is suppressed.

The contact angle described above is 70 deg or more and 80 deg or less. As a result, in the camera device 100, water droplets on the surface of the flange 21 are more easily discharged, a decrease in the flow velocity of the wind is suppressed, and adhesion of water droplets on the lens 3 is further suppressed.

The above description has been made based on the embodiment of the present invention. It will be appreciated by those skilled in the art that these embodiments are exemplary and that various modifications and modifications are possible within the claims of the invention, and that such modifications and modifications are also within the claims of the present invention. It is about to be done. Therefore, the descriptions and drawings herein should be treated as exemplary rather than limiting.

2 lens barrel, 21 flange, 26 surface treatment film, 3 lens,
100 camera device.

Claims (4)

With a lens exposed to the outside air
In a camera device including a lens barrel having a flange covering the outer edge of the lens.
A surface treatment film is formed on the front surface of the flange.
A camera device characterized in that the surface-treated film is formed by alumite treatment. The camera device according to claim 1, wherein the surface-treated film is formed by a glossy alumite treatment. With a lens exposed to the outside air
In a camera device including a lens barrel having a flange covering the outer edge of the lens.
A surface treatment film is formed on the front surface of the flange.
A camera device characterized in that the contact angle formed by the outer surface of water droplets adhering to the surface treatment film and the surface is 60 deg or more and 80 deg or less. The camera device according to claim 3, wherein the contact angle is 70 deg or more and 80 deg or less.

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