Prime lens

Abstract

The utility model belongs to the technical field of lenses, and discloses a prime lens, the prime lens comprises a lens barrel, a pressing ring and a lens assembly, the pressing ring and the lens assembly are both arranged in the lens barrel, a limiting part is arranged in the lens barrel, the pressing ring presses the lens assembly on the limiting part along the axis direction of the lens barrel, and the lens assembly is arranged in the limiting part. And the outer wall of the pressing ring is fixedly connected with the inner wall of the lens barrel in a hot melting manner. According to the prime lens provided by the utility model, the lens assembly is pressed in the lens barrel by the pressing ring, so that the pressing ring is fixedly connected with the lens barrel in a hot melting manner, and subsequent lens recovery is facilitated.

Description

Technical Field

[0001] The utility model relates to the technical field of lenses, in particular to a fixed-focus lens. Background Art

[0002] The focal length of a fixed-focus lens is fixed, the focusing speed is fast, and the image quality is stable. Since there is no zoom mechanism, the fixed-focus lens is smaller in size and lighter in weight, making it easy to carry and use for a long time.

[0003] In a fixed-focus lens, there are three ways to fix the lens inside the lens barrel. The first is to use screws to lock the lens to the lens barrel. Screw locking will increase the overall aperture size of the lens and reduce the available space for other components. The second is to use glue to bond the lens to the lens barrel. Glue fixing is not conducive to the disassembly of the lens and the lens cannot be recycled. The third is to heat-seal the lens to the lens barrel, which is also not conducive to the recycling of the lens. Utility Model Content

[0004] The utility model aims to provide a fixed-focus lens, which uses a pressing ring to press the lens assembly tightly against the inside of the lens barrel, so that the pressing ring and the lens barrel are fixedly connected by hot melting, thereby facilitating the subsequent recycling of the lens.

[0005] To achieve this purpose, the present invention adopts the following technical solutions:

[0006] A fixed-focus lens includes a lens barrel, a pressure ring and a lens assembly. The pressure ring and the lens assembly are both arranged inside the lens barrel. A limiting portion is provided inside the lens barrel. The pressure ring presses the lens assembly against the limiting portion along the axial direction of the lens barrel. The outer wall of the pressure ring is fixedly connected to the inner wall of the lens barrel by hot melting.

[0007] As an optional technical solution, the pressure rings are provided with two, the two pressure rings are respectively a front pressure ring and a rear pressure ring, and the lens assembly is provided in two groups, the two groups of lens assemblies are respectively a front lens assembly and a rear lens assembly;

[0008] One side of the limiting portion is a front mounting cavity, and the front pressure ring and the front lens assembly are located in the front mounting cavity;

[0009] The other side of the limiting portion is a rear mounting cavity, and the rear pressure ring and the rear lens assembly are located in the rear mounting cavity.

[0010] As an optional technical solution, the limiting portion is integrally provided with the lens barrel.

[0011] As an optional technical solution, the limiting portion is a spacer ring, and the spacer ring and the lens barrel are provided separately.

[0012] As an optional technical solution, the lens barrel is made of plastic, and the pressure ring is made of metal.

[0013] As an optional technical solution, the end face of the pressure ring facing away from the lens assembly is provided with an annular heat-melting surface. In the radial direction of the lens barrel, the distance from the inner ring edge of the heat-melting surface to the outer wall of the pressure ring is a, and a≧0.3 mm.

[0014] As an optional technical solution, the pressure ring and the lens assembly are in line contact, the contact line between the pressure ring and the lens assembly is annular, and in the radial direction of the lens barrel, the distance from the contact line to the outer wall of the pressure ring is b, and b≧0.4 mm;

[0015] Alternatively, the pressure ring and the lens assembly are in surface contact, the contact surface between the pressure ring and the lens assembly is annular, and in the radial direction of the lens barrel, the distance from the inner ring edge of the contact surface to the outer wall of the pressure ring is b, and b≧0.4 mm.

[0016] As an optional technical solution, in the axial direction of the lens barrel, the contact length between the outer wall of the pressure ring and the inner wall of the lens barrel is d, and 0.2 mm≤d≤1 mm.

[0017] As an optional technical solution, a bearing portion is provided at the end of the lens barrel, and in the radial direction of the lens barrel, the bearing portion covers the pressing ring or a part of the pressing ring;

[0018] In the axial projection of the lens barrel, the bearing portion is annular, and the axial length of the bearing portion is c, 0.3 mm≤c≤1 mm.

[0019] As an optional technical solution, in the axial direction of the lens barrel, the end face of the bearing portion is annular, and the distance from the inner edge of the end face to the outer edge of the end face is e, 0.3 mm ≤ e ≤ 0.5 mm.

[0020] Beneficial effects of the utility model:

[0021] The utility model provides a fixed-focus lens, which includes a lens barrel, a pressure ring and a lens assembly. The pressure ring and the lens assembly are both arranged inside the lens barrel. A limiting portion is provided inside the lens barrel. The pressure ring presses the lens assembly against the limiting portion along the axial direction of the lens barrel. The outer wall of the pressure ring is fixedly connected to the inner wall of the lens barrel by hot melting.

[0022] The lens assembly is confined between the pressure ring and the limit part to prevent the lens assembly from moving; the price of the pressure ring is much lower than that of the lens assembly. When the lens assembly needs to be recycled, only the pressure ring needs to be removed to take out the lens assembly to prevent damage to the lens assembly; the pressure ring and the lens barrel are fixed by hot melt, and no additional screws or other locking parts are required. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a cross-sectional view of the fixed-focus lens of the present utility model;

[0024] Figure 2 yes Figure 1 A partial enlarged view of position A in the middle;

[0025] Figure 3 yes Figure 1 A partial enlarged view of position B in the middle.

[0026] In the picture:

[0027] 1. Lens barrel; 11. Limiting part; 12. Carrying part;

[0028] 2. Pressing ring; 21. Hot melt surface; 22. Parallel surface;

[0029] 3. Lens assembly; 31. First lens; 32. Front lens group; 33. Second lens; 34. Rear lens group. DETAILED DESCRIPTION

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention. It should also be noted that, for ease of description, the accompanying drawings only illustrate portions relevant to the present invention, not all of its components.

[0031] In the description of this utility model, unless otherwise specified or limited, the terms "connected," "connect," and "fixed" should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0032] In the present invention, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may include the first and second features being in direct contact, or may include the first and second features being in contact not directly but through another feature between them. Moreover, a first feature being "above," "above," and "above" a second feature may include the first feature being directly above or obliquely above the second feature, or may simply mean that the first feature is higher in level than the second feature. A first feature being "below," "below," and "below" a second feature may include the first feature being directly below or obliquely below the second feature, or may simply mean that the first feature is lower in level than the second feature.

[0033] In the description of this embodiment, the terms "upper," "lower," "right," and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely for ease of description and simplified operation. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. Furthermore, the terms "first" and "second" are used solely for descriptive purposes and have no special meaning.

[0034] like Figures 1 to 3 As shown, the fixed-focus lens provided in this embodiment includes a lens barrel 1, a pressure ring 2 and a lens assembly 3. The pressure ring 2 and the lens assembly 3 are both arranged inside the lens barrel 1. A limiting portion 11 is provided inside the lens barrel 1. The pressure ring 2 presses the lens assembly 3 to the limiting portion 11 along the axial direction of the lens barrel 1. The outer wall of the pressure ring 2 is fixedly connected to the inner wall of the lens barrel 1 by hot melting.

[0035] Specifically, the lens assembly 3 is confined between the pressure ring 2 and the limiting portion 11 to prevent the lens assembly 3 from moving; the price of the pressure ring 2 is much lower than that of the lens assembly 3. When the lens assembly 3 needs to be recycled, it is only necessary to remove the pressure ring 2 to take out the lens assembly 3 to prevent the lens assembly 3 from being damaged; the pressure ring 2 and the lens barrel 1 are fixedly connected by hot melt, and no additional screws or other locking parts are required.

[0036] In this embodiment, two pressure rings 2 are provided, which are respectively a front pressure ring and a rear pressure ring; the lens assembly 3 is provided in two groups, which are respectively a front lens assembly and a rear lens assembly; one side of the limiting portion 11 is a front mounting cavity, and the front pressure ring and the front lens assembly are located in the front mounting cavity; the other side of the limiting portion 11 is a rear mounting cavity, and the rear pressure ring and the rear lens assembly are located in the rear mounting cavity.

[0037] The front lens assembly and the rear lens assembly are respectively arranged on both sides of the limiting portion 11 , and the front lens assembly and the rear lens assembly are spaced apart along the axial direction of the lens barrel 1 .

[0038] The front lens assembly includes a first lens 31 and a front lens group 32. The front pressure ring, the first lens 31 and the front lens group 32 are arranged in sequence along the axial direction of the lens barrel 1. The front lens group 32 abuts against the limiting portion 11, the first lens 31 abuts against the front lens group 32, and the front pressure ring abuts against the first lens 31; the rear lens assembly includes a second lens 33 and a rear lens group 34. The rear pressure ring, the second lens 33 and the rear lens group 34 are arranged in sequence along the axial direction of the lens barrel 1. The rear lens group 34 abuts against the limiting portion 11, the second lens 33 abuts against the rear lens group 34, and the rear pressure ring abuts against the second lens 33.

[0039] In some other embodiments, the pressure ring 2 is provided as one and the lens assembly 3 is provided as a group.

[0040] In this embodiment, the limiting portion 11 is integrally provided with the lens barrel 1. A through hole is provided in the middle of the limiting portion 11 to connect the front mounting cavity and the rear mounting cavity.

[0041] In some other embodiments, the limiting portion 11 is a spacer ring, which is provided separately from the lens barrel 1 .

[0042] In this embodiment, the lens barrel 1 is made of plastic, and the pressing ring 2 is made of metal. The lens barrel 1 made of plastic is lighter, and the pressing ring 2 made of metal can provide sufficient structural strength; plastic and metal are easier to connect by hot-melt fixing.

[0043] Optionally, the end surface of the pressing ring 2 facing away from the lens assembly 3 is provided with an annular heat-melting surface 21 , and in the radial direction of the lens barrel 1 , the distance from the inner edge of the heat-melting surface 21 to the outer wall of the pressing ring 2 is a, and a≧0.3 mm.

[0044] The distance from the inner edge of the hot melt surface 21 to the outer wall of the pressing ring 2 is greater than or equal to 3 mm to prevent the hot melt surface 21 from being too small and resulting in insufficient connection strength, thereby ensuring the hot melt integrity of the lens barrel 1 and the pressing ring 2.

[0045] In some cases, the end surface of the pressure ring 2 facing away from the lens assembly 3 is a plane, and in other cases, the end surface of the pressure ring 2 facing away from the lens assembly 3 is a stepped surface.

[0046] In this embodiment, the end face of the front pressure ring facing away from the first lens 31 is a stepped surface, which includes a heat-melt surface 21 and a parallel surface 22; in the axial direction of the lens barrel 1, the heat-melt surface 21 and the parallel surface 22 are arranged in parallel, and the distance from the heat-melt surface 21 to the first lens 31 is smaller than the distance from the parallel surface 22 to the first lens 31; in the radial direction of the lens barrel 1, the heat-melt surface 21 is located between the parallel surface 22 and the inner wall of the lens barrel 1.

[0047] In this embodiment, the end surface of the rear pressure ring facing away from the second lens 33 is a plane, and the plane is the heat-melting surface 21 .

[0048] Optionally, there is line contact between the pressure ring 2 and the lens assembly 3, the contact line between the pressure ring 2 and the lens assembly 3 is annular, and in the radial direction of the lens barrel 1, the distance value from the contact line to the outer wall of the pressure ring 2 is b, b≧0.4 mm; or, there is surface contact between the pressure ring 2 and the lens assembly 3, the contact surface between the pressure ring 2 and the lens assembly 3 is annular, and in the radial direction of the lens barrel 1, the distance value from the inner ring edge of the contact surface to the outer wall of the pressure ring 2 is b, b≧0.4 mm.

[0049] Setting the distance value b to be greater than or equal to 0.4 mm can ensure the stability of the pressure ring 2 pressing the lens assembly 3. The distance value is the pressing distance of the pressure ring 2 on the lens assembly 3. If the pressing distance is too small, the pressure ring 2 can only press against the edge of the lens assembly 3 and cannot ensure the stability of the lens assembly 3.

[0050] In this embodiment, the side of the first lens 31 facing the front pressure ring is a spherical surface, and there is line contact between the front pressure ring and the first lens 31. The size of the covering distance value is more important to the stability of the first lens 31. The side of the second lens 33 facing the rear pressure ring is composed of a spherical surface and an annular contact surface. The contact surface surrounds the circumference of the spherical surface, and there is surface contact between the contact surface of the rear pressure ring and the second lens 33.

[0051] Optionally, in the axial direction of the lens barrel 1 , the contact length between the outer wall of the pressing ring 2 and the inner wall of the lens barrel 1 is d, 0.2 mm≤d≤1 mm, to ensure the coaxiality of the pressing ring 2 and the lens barrel 1 .

[0052] Optionally, a bearing portion 12 is provided at the end of lens barrel 1. In the radial direction of lens barrel 1, bearing portion 12 covers pressing ring 2 or a portion of pressing ring 2. In the axial projection of lens barrel 1, bearing portion 12 is annular, and the axial length of bearing portion 12 is c, where 0.3 mm ≤ c ≤ 1 mm. The axial length of bearing portion 12 is controlled to be between 0.3 mm and 1 mm to ensure the thermal fusion securement between lens barrel 1 and pressing ring 2.

[0053] In this embodiment, a bearing portion 12 is provided at both ends of the lens barrel 1. In the radial direction of the lens barrel 1, the bearing portion 12 located at the front end completely covers a portion of the front pressure ring having a parallel surface 22, a portion of the front pressure ring having a hot-melt surface 21 is staggered with the bearing portion 12 located at the front end, and the bearing portion 12 located at the rear end completely covers the rear pressure ring.

[0054] Optionally, in the axial direction of the lens barrel 1 , the end face of the bearing portion 12 is annular, and the distance from the inner edge of the end face to the outer edge of the end face is e, and 0.3 mm ≤ e ≤ 0.5 mm.

[0055] In order to improve the operability of the hot melt machine in hot melting the pressure ring 2 and the lens barrel 1, the distance from the inner ring edge of the end face to the outer ring edge of the end face is set between 0.3 mm and 0.5 mm.

[0056] Obviously, the above-described embodiments of the present invention are merely examples for the purpose of clearly illustrating the present invention and are not intended to limit the manner in which the present invention is to be implemented. A person skilled in the art would be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is not necessary and impossible to enumerate all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the claims of the present invention.

Claims

1. Fixed focus lens, characterized by: The invention comprises a lens barrel (1), a pressing ring (2) and a lens assembly (3); the pressing ring (2) and the lens assembly (3) are both arranged inside the lens barrel (1); a limiting portion (11) is provided inside the lens barrel (1); the pressing ring (2) presses the lens assembly (3) against the limiting portion (11) along the axial direction of the lens barrel (1); and the outer wall of the pressing ring (2) is fixedly connected to the inner wall of the lens barrel (1) by hot melting.

2. The fixed-focus lens according to claim 1, wherein: The pressure rings (2) are provided with two, and the two pressure rings (2) are respectively a front pressure ring and a rear pressure ring; the lens assembly (3) is provided with two groups, and the two groups of lens assemblies (3) are respectively a front lens assembly and a rear lens assembly; One side of the limiting portion (11) is a front mounting cavity, and the front pressure ring and the front lens assembly are located in the front mounting cavity; The other side of the limiting portion (11) is a rear mounting cavity, and the rear pressure ring and the rear lens assembly are located in the rear mounting cavity.

3. The fixed-focus lens according to claim 1, wherein: The limiting portion (11) is integrally provided with the lens barrel (1).

4. The fixed-focus lens according to claim 1, wherein: The limiting portion (11) is a spacer ring, and the spacer ring and the lens barrel (1) are arranged separately.

5. The fixed-focus lens according to claim 1, wherein: The material of the lens barrel (1) is plastic, and the material of the pressure ring (2) is metal.

6. The fixed-focus lens according to claim 5, wherein: The end surface of the pressing ring (2) facing away from the lens assembly (3) is provided with an annular heat-melting surface (21). In the radial direction of the lens barrel (1), the distance value from the inner ring edge of the heat-melting surface (21) to the outer wall of the pressing ring (2) is a, and a≧0.3 mm.

7. The fixed-focus lens according to claim 5, wherein: There is line contact between the pressing ring (2) and the lens assembly (3), the contact line between the pressing ring (2) and the lens assembly (3) is annular, and in the radial direction of the lens barrel (1), the distance value from the contact line to the outer wall of the pressing ring (2) is b, and b≧0.4 mm; Alternatively, the pressing ring (2) and the lens assembly (3) are in surface contact, the contact surface between the pressing ring (2) and the lens assembly (3) is annular, and in the radial direction of the lens barrel (1), the distance from the inner ring edge of the contact surface to the outer wall of the pressing ring (2) is b, and b≧0.4 mm.

8. The fixed-focus lens according to claim 5, wherein: In the axial direction of the lens barrel (1), the contact length between the outer wall of the pressure ring (2) and the inner wall of the lens barrel (1) is d, and 0.2 mm ≤ d ≤ 1 mm.

9. The fixed-focus lens according to claim 5, wherein: The end of the lens barrel (1) is provided with a bearing portion (12), and in the radial direction of the lens barrel (1), the bearing portion (12) covers the pressing ring (2) or a portion of the pressing ring (2); In the axial projection of the lens barrel (1), the bearing portion (12) is annular, and the axial length of the bearing portion (12) is c, 0.3 mm ≤ c ≤ 1 mm.

10. The fixed-focus lens according to claim 9, wherein: In the axial direction of the lens barrel (1), the end face of the bearing portion (12) is annular, and the distance value from the inner ring edge of the end face to the outer ring edge of the end face is e, and 0.3 mm ≤ e ≤ 0.5 mm.

Images