Lens barrel components and lens unit

Abstract

This technology provides a way to suppress the increase in the number of parts and assembly costs in lens unit assemblies having multiple lenses. [Solution] A lens barrel component that can be assembled into a cylindrical shape, wherein the lens barrel includes a plurality of lens barrel pieces divided in the circumferential direction of the cylindrical shape, at least two of the plurality of lens barrel pieces are connected to each other via bent portions at their respective dividing surfaces, and at least one of the plurality of lens barrel pieces has a positioning portion that determines the position of the lens on the inner circumferential surface of the lens barrel. The cylindrical lens barrel can be assembled by joining the unconnected dividing surfaces of the plurality of lens barrel pieces.

Description

Technical Field

[0001] The present invention relates to a lens barrel component and a lens unit using the same.

Background Art

[0002] In recent years, due to the improvement in the accuracy of CMOS sensors and the development of communication technologies, cameras have been installed in all devices, increasing the demand for small lens units. In small lens units, small-diameter plastic lenses are frequently used. However, when incorporating multiple plastic lenses into a lens barrel, it is necessary to align the optical axes of each lens for centering. Therefore, it is necessary to form tapered surfaces for centering on the outer periphery of each lens and the lens barrel, making the molding process complicated. In addition, when incorporating a light shielding plate for preventing stray light between each plastic lens, the number of components increases, complicating the assembly.

[0003] In order to address such complication in assembly, Patent Document 1 discloses a lens assembly manufactured by constructing a split lens barrel that is pre-divided in the radial direction, positioning and holding each lens in one side of the split lens barrel, and then overlapping the other side of the split lens barrel.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the configuration disclosed in Patent Document 1, after incorporating a lens into one of the two split lens barrels, an operation of assembling the other split lens barrel with respect to the set of the one split lens barrel and the lens occurs. At this time, the assembly of the other split lens barrel and the lens may not go well. The present disclosure aims to provide a technology capable of easily assembling a lens barrel. [Means for solving the problem]

[0006] This disclosure provides a lens barrel component that can be assembled into a cylindrical lens barrel, wherein the lens barrel includes a plurality of lens barrel pieces divided in the circumferential direction of the cylindrical shape, at least two of the plurality of lens barrel pieces are connected to each other via bent portions at their respective dividing surfaces, at least one of the plurality of lens barrel pieces has a positioning portion that determines the position of a lens on the inner circumferential surface of the lens barrel, and the component is configured to be assembled into the cylindrical lens barrel by joining at least two of the unconnected dividing surfaces of the plurality of lens barrel pieces to each other, thereby achieving the above objective. [Effects of the Invention]

[0007] According to this disclosure, the assembly of the telescope tube becomes easier. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view showing a lens unit, which is one embodiment of the present invention. [Figure 2] This is a perspective view showing a lens barrel component, which is one embodiment of the present invention. [Figure 3] This is a cross-sectional view showing an example of a mold used in the manufacture of a lens barrel component, which is one embodiment of the present invention. [Figure 4] This diagram illustrates an example of how to assemble a lens unit, which is one embodiment of the present invention. [Figure 5] This diagram illustrates an example of how to assemble a lens unit, which is one embodiment of the present invention. [Figure 6] This figure illustrates another example of a method for assembling a lens unit, which is one embodiment of the present invention. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. However, the embodiments described below are just one embodiment of the present invention, and the present invention is not limited thereto. Common components will be described with reference to multiple drawings, and components with common reference numerals will be omitted from the description as appropriate. Different items with the same name can be distinguished by adding "item number ○," such as "item number 1," "item number 2," etc.

[0010] <Lens barrel components, lens unit> A lens unit constructed using the lens barrel component of the present invention will be explained with reference to Figure 1. Figure 1 is a perspective view of the lens unit 100. The lens unit 100 consists of a lens barrel component 101 and a lens portion 1 disposed inside it. The lens portion 1 is manufactured from a transparent material (glass material) such as a transparent resin represented by polycarbonate, acrylic, or cyclic olefin polymer, or a glass material represented by BK7, and the glass material and shape are selected based on the desired lens performance.

[0011] Figure 2 will be used to illustrate the lens barrel component 101 that constitutes the lens unit 100 of the present invention. Figure 2 shows the internal view when the lens barrel component 101 that constitutes the lens unit 100 is opened around the bending portion 102. The lens barrel component 101 is composed of two lens barrel pieces in which a cylindrical lens barrel is divided in half by a plane passing through the optical axis, and one end of each lens barrel piece's dividing surface (both end faces, i.e., the cut surface by the above-mentioned plane) is connected to the other end by the bending portion 102 so as to be bendable toward each other. That is, the two lens barrel pieces that constitute the cylindrical lens barrel component are connected (linked) via the bending portion 102, forming a strip-shaped integrated structure. The other end of each lens barrel piece's dividing surface (i.e., located at both ends of the strip-shaped integrated structure) is separated from the other end by opening stoppers 103 and 104. In other words, the opening stoppers 103 and 104 are shaped to snap into place with each other, and are located opposite the bending portion 102 when the lens barrel component 101 is assembled into a cylindrical lens barrel. The cylindrical shape is maintained and fixed by engaging the opening stoppers 103 and 104. Note that the lens barrel component 101 in Figure 2 is composed of two lens barrel pieces, which are formed when a cylindrical lens barrel is divided in half by a plane passing through the optical axis (which can also be viewed as two half-planes that share the optical axis and connect at a 180-degree angle to each other). However, the lens barrel component of the present invention only needs to consist of lens barrel pieces in which a cylindrical lens barrel is divided into two or more pieces in the circumferential direction by two or more half-planes that share the optical axis. For example, it may consist of lens barrel pieces divided into three or four sections in the circumferential direction. Also, in Figure 2, all the divided lens barrel pieces are connected by the bending portion to form a strip-shaped integrated structure, but it is sufficient that at least two of the divided lens barrel pieces have one dividing surface connected to each other via the bending portion. For example, it may consist of two connecting tube sections, each made up of two adjacent tube sections that are separately connected to each other, which are divided into four circumferential sections. The bent section can be a hinge structure made of a hinge or a flexible member, and its specific structure and shape are not limited.

[0012] In this embodiment, the lens section 1 is a lens assembly composed of a first lens 11, a second lens 12, and a third lens 13 (see Figure 5). Ring-shaped lens storage grooves 21, 22, and 23 are formed on the inner circumferential surface of the lens barrel component 101 to fix the position of each lens. Between each of the lens storage grooves 21, 22, and 23, light-shielding sections 31 and 32 are integrally formed as ring-shaped protrusions on the lens barrel component 101, serving as spacers to determine the distance between the lenses and to block unwanted light (stray light) entering each lens. Note that the positioning sections for fixing the lens positions do not necessarily have to be ring-shaped grooves (lens storage grooves); for example, they may be multiple protrusions formed on the inner surface of at least one lens barrel piece constituting the lens barrel component (the surface forming the inner circumferential surface of the lens barrel). However, ring-shaped grooves have the advantage of facilitating lens loading during the manufacturing process of the lens barrel, as will be described later. Furthermore, if a light-shielding section is provided between the lenses to prevent stray light, there is the advantage that the ring-shaped protrusions formed on both sides of the ring-shaped groove can also serve as the light-shielding section.

[0013] Figure 3 is a cross-sectional view showing the internal structure of the mold used in the manufacturing method of the lens barrel component 101 of this embodiment. The lens barrel component 101 is manufactured by injection molding. That is, molten resin (not shown) is injected into the runner 201 of the mold 200, and then flows through the sub-runner 202 into the cavity 203 that forms the lens barrel component 101. The bent portion 102 is also formed at the same time as the manufacturing of the lens barrel component 101, and the lens barrel component 101 connected by the bent portion 102 is obtained in a single manufacturing process. Then, after opening the mold, the lens barrel component 101 is removed from the mold with an ejector pin 204. In this injection molding method for manufacturing the lens barrel component 101, by manufacturing the bent portion 102 integrally in an open state, it is possible to avoid having an undercut portion in the mold, and thus it can be easily manufactured without using a complex mold structure. Examples of materials used in the manufacturing of the lens barrel component 101 include thermoplastic resins such as polycarbonate. The material for the lens barrel component 101 can be selected considering factors such as strength and environmental resistance, but it is desirable to select a material with hinge properties (flexibility) in order to allow the bent portion 102 to move in a later process. Furthermore, it is desirable that the lens barrel component 101 be manufactured from an opaque material in order to block light from outside the optical plane.

[0014] Figure 4 illustrates the process of assembling the first lens 11 into the lens barrel component 101. The lens barrel component 101 is placed on the assembly jig 300 with the bending portion 102 slightly bent in the direction that closes the lens barrel. The opening angle at this time is such that the first lens 11 can be inserted from the opening (the side opposite the bending portion 102) and the first lens 11 can be simultaneously housed in the lens storage grooves 21 of both lens barrel pieces of the lens barrel component 101. Next, the first lens 11 is inserted from the opening of the lens barrel component 101 and into the lens storage groove 21 on the bending portion 102 side. At this time, the first lens 11 is positioned so that it straddles the lens storage grooves 21 of both lens barrel pieces constituting the lens barrel component 101, that is, the lens storage grooves 21 of both lens barrel pieces sandwich the first lens 11. The second lens 12 and the third lens 13 are inserted into the lens storage grooves 22 and 23, respectively, using a similar procedure.

[0015] Figure 5 shows the process of closing the lens barrel component 101, into which the first to third lenses 11, 12, and 13 are inserted, to deform it into a cylindrical shape, and assembling it into a lens unit with the three lenses housed inside. Figure 5(a) shows the state in which the three lenses are fitted across the lens storage grooves of both lens barrel pieces of the lens barrel component 101. Figure 5(b) shows the state in which the lens barrel component 101 is bent around the bending portion 102 as an axis and deformed into a cylindrical shape. Since each lens 11, 12, and 13 is positioned by the lens storage grooves 21, 22, and 23 in the previous step, there are no new fitting points in the process of achieving the position shown in Figure 5(b), and each lens can be smoothly housed inside the lens barrel. Finally, the lens unit 100 is completed by engaging the opening stopper portions 103 and 104 with each other.

[0016] In this embodiment, a pair of snap-fit ​​stoppers that connect the divided surfaces located at both ends of a strip-shaped integrated structure is used as a joint retention mechanism to prevent the cylindrical assembled lens barrel component from opening. However, other methods can be used to prevent the lens barrel component from opening. For example, the joint surfaces of the lens barrel component 101 may be bonded with instant adhesive, or the joint surfaces of the lens barrel component 101 may be heated and welded. Alternatively, the outer circumference of the lens barrel component 101 may be tightened and fixed with a ring-shaped member.

[0017] Furthermore, in this embodiment, the three lenses are inserted so as to span the lens storage grooves of both barrel sections of the lens barrel component 101, but the method of assembling the lenses into the open lens barrel component is not limited to this. For example, as shown in Figure 6, the lens unit 100 can also be manufactured by first inserting all the lenses into the lens storage groove of one barrel section of the lens barrel component 101, and then closing the lens barrel component 101 to deform it into a cylindrical shape. In this case, for example, if the dimensions of the lens storage groove 21 on one side of the lens barrel into which the lenses are inserted first are manufactured with high precision, and the lens storage groove 21 on the other side of the lens barrel that is closed later has a structure with clearance, the fitting length can be reduced, and the lenses can be assembled into the inside of the lens barrel component 101 relatively easily.

[0018] In addition, in this embodiment, the cylindrical lens barrel is evenly divided into two lens barrel pieces by a plane passing through the optical axis. However, the lens barrel may be divided into three or more lens barrel pieces, and it does not necessarily have to be evenly divided. When it is divided into three or more lens barrel pieces, there will be two or more bending portions. At this time, when inserting a plurality of lenses into the lens storage groove, it is preferable to select one location from two or more bending portions or three or more lens barrel pieces and insert all the lenses there.

[0019] <Imaging unit, information device> An imaging unit can be configured by combining a lens unit in which a lens is incorporated into the lens barrel component of the present invention and an imaging element such as a CMOS sensor. By using the lens barrel component of the present invention, a high-precision lens unit incorporating a plurality of small lenses can be manufactured at low cost. Therefore, a small imaging unit (for example, a camera unit) configured by combining it with a small imaging element and a small information device (for example, a smartphone) incorporating a small display element (for example, an organic EL element) can also be manufactured at low cost.

[0020] The present invention is not limited to the embodiments described above, and many modifications are possible within the technical idea of the present invention. Also, the effects described in the above embodiments are merely an enumeration of the most preferable effects resulting from the present invention, and the effects of the present invention are not limited to those described in the embodiments.

[0021] The present invention includes embodiments having the following configurations. (Configuration 1)<着脱可能なレンズユニットを備える撮像装置> A lens barrel component that can be assembled into a cylindrical lens barrel, wherein the lens barrel includes a plurality of lens barrel pieces divided in the circumferential direction of the cylindrical shape, at least two of the plurality of lens barrel pieces are connected to each other via bent portions at their respective dividing surfaces, at least one of the plurality of lens barrel pieces has a positioning portion on the inner circumferential surface of the lens barrel that determines the position of the lens, and the component is configured to be assembled into the cylindrical lens barrel by joining at least two of the unconnected dividing surfaces of the plurality of lens barrel pieces to each other. (Configuration 2) The plurality of lens barrel pieces are lens barrel components of configuration 1, wherein the lens barrel is divided by two or more half-planes passing through the axis of the cylindrical shape, and at least two lens barrel pieces are made up of these lens barrel pieces. (Composition 3) The lens barrel component of configuration 2, wherein each of the plurality of lens barrel pieces has at least one dividing surface connected to one dividing surface of another lens barrel piece via the bending portion to form a strip-shaped integrated structure, and the dividing surfaces located at both ends of the strip-shaped integrated structure are joined together to form the cylindrical lens barrel. (Composition 4) A lens barrel component of configuration 3, having a joint retention mechanism for preventing the cylindrical lens barrel from opening due to the separation of the joints between the divided surfaces located at both ends of the aforementioned strip-shaped integrated structure. (Composition 5) The lens barrel component of configuration 4, wherein the joining retention mechanism is a pair of snap-fit ​​shaped opening stoppers that connect the divided surfaces located at both ends of the strip-shaped integral structure to each other. (Composition 6) The lens barrel component of configuration 5, wherein the lens barrel is divided into two lens barrel pieces, and the opening stopper is located at a position opposite to the bent portion that connects the two lens barrel pieces in the cylindrical shape. (Composition 7) The positioning portion is a ring-shaped lens housing groove formed on the inner circumferential surface of the lens barrel, which is a lens barrel component of any of configurations 1 to 6. (Composition 8) A lens barrel component of configuration 7, wherein a plurality of lens storage grooves are formed on the inner circumferential surface of the lens barrel, and between the plurality of lens storage grooves, there are ring-shaped protrusions that function as light-shielding portions to block stray light or as spacers to determine the distance between lenses. (Composition 9) A method for manufacturing a lens unit, comprising opening one of the lens barrel components of configurations 1 to 8, inserting a lens into the lens storage groove across one of the bent portions, and then closing the lens barrel component using the bent portion as an axis to manufacture the lens unit. (Composition 10) A lens unit comprising a lens barrel component of one of configurations 1 to 8 and a lens disposed inside it. (Composition 11) An imaging unit comprising a lens unit and an image sensor, each with a configuration of 10 elements. (Composition 12) An information device comprising an imaging unit and a display element, as described in configuration 11. [Explanation of symbols]

[0022] 1. Lens section 11 First Lens 12 Second Lens 13 Third Lens 21 Lens storage groove (for the first lens) 22 Lens storage groove (for the second lens) 23 Lens storage groove (for the third lens) 31 Light-shielding part 32 Light-shielding part 100 Lens Unit 101 Telescope Tube Parts 102 Folding section 103 Opening stopper 104 Opening stopper 200 molds 201 Runners 202 Subrunner 203 Cavity 204 Ejector pins 300 Assembly Jigs

Claims

1. A lens barrel component that can be assembled into a cylindrical lens barrel, wherein the lens barrel includes a plurality of lens barrel pieces divided in the circumferential direction of the cylindrical shape, at least two of the plurality of lens barrel pieces are connected to each other via bent portions at their respective divided surfaces, at least one of the plurality of lens barrel pieces has a positioning portion on the inner circumferential surface of the lens barrel that determines the position of the lens, and the lens barrel component is configured to be assembled into a cylindrical lens barrel by joining at least two of the unconnected divided surfaces of the plurality of lens barrel pieces to each other.

2. The lens barrel component according to claim 1, wherein the plurality of lens barrel pieces consist of at least two lens barrel pieces in which the lens barrel is divided by two or more half-planes passing through the axis of the cylindrical shape.

3. The lens barrel component according to claim 2, wherein each of the plurality of lens barrel pieces is configured such that at least one dividing surface is connected to one dividing surface of another lens barrel piece via the bending portion to form a strip-shaped integrated structure, and the dividing surfaces located at both ends of the strip-shaped integrated structure are joined together to form the cylindrical lens barrel.

4. The lens barrel component according to claim 3, further comprising a joint retention mechanism for preventing the cylindrical lens barrel from opening due to the separation of the joints between the divided surfaces located at both ends of the aforementioned strip-shaped integral structure.

5. The lens barrel component according to claim 4, wherein the joining maintenance mechanism is a pair of snap-fit ​​shaped opening stoppers that connect the divided surfaces located at both ends of the strip-shaped integral structure to each other.

6. The lens barrel component according to claim 5, wherein the lens barrel is divided into two lens barrel pieces, and the opening stopper is located at a position opposite to the bent portion that connects the two lens barrel pieces in the cylindrical shape.

7. The lens barrel component according to any one of claims 1 to 6, wherein the positioning portion is a ring-shaped lens housing groove formed on the inner circumferential surface of the lens barrel.

8. The lens barrel component according to claim 7, wherein a plurality of lens housing grooves are formed on the inner circumferential surface of the lens barrel, and a ring-shaped protrusion is provided between the plurality of lens housing grooves, having the function of a light-shielding portion that blocks stray light or a spacer that determines the distance between lenses.

9. A method for manufacturing a lens unit, comprising inserting a lens into the lens storage groove across one of the bent portions while the lens barrel component described in claim 7 is open, and then closing the lens barrel component with the bent portion as the axis to manufacture the lens unit.

10. A lens unit comprising the lens barrel component described in claim 1 and a lens disposed inside it.

11. An imaging unit comprising the lens unit and image sensor described in claim 10.

12. An information device comprising the imaging unit and display element described in claim 11.

Images