CN211063664U

CN211063664U - Miniature lens subassembly and camera module

Info

Publication number: CN211063664U
Application number: CN201921954222.1U
Authority: CN
Inventors: 盛斌
Original assignee: Individual
Current assignee: Shanghai Yousuan Information Technology Co ltd
Priority date: 2019-11-13
Filing date: 2019-11-13
Publication date: 2020-07-21
Anticipated expiration: 2029-11-13

Abstract

The utility model provides a miniature lens subassembly and camera module, miniature lens module includes: a single lens, said lens being a single-sided aspherical lens having opposing first and second surfaces, said first surface being planar and said second surface being curved; the first surface of the lens is square, and the side length is 0.5 mm. The lens assembly includes a single wafer, reducing the size of the lens module.

Description

Miniature lens subassembly and camera module

Technical Field

The utility model relates to an endoscope technical field especially relates to a miniature camera lens subassembly and camera module.

Background

CMOS (Complementary Metal-Oxide-Semiconductor), known as CMOS in chinese, is an important branch of Semiconductor manufacturing processes. In recent years CMOS processes have also been used to fabricate image sensors in production of digital photography, referred to as CMOS image video sensors. Compared with the CCD technology monopolizing the field for more than 30 years, the CCD imaging device can better meet the continuously improved quality requirements of users on novel image sensors in various applications, such as more flexible image capture, higher sensitivity, wider dynamic range, higher resolution, lower power consumption, more excellent system integration and the like.

In the occasions with strict requirements on the size and the weight of an imaging system, a micro lens is required to be matched with a micro CMOS imaging device to realize related application, and the micro lens can be used in products such as endoscopes, remote control robots and unmanned reconnaissance planes.

Similar technical schemes exist in the prior art, for example, OmniVision microsensors, such as OmniVision OVs, american semiconductor companies, the chinese name haunware technology, which is based on 1995, and professionally developed highly integrated CMOS image technology, OmniVision produces 0.575(mm) × 0.575.575 (mm) CMOS sensors, but the sensors are sold only in a chip mode, and no imaging module product is sold at present, so that the products cannot be quickly formed.

Therefore, it is necessary to provide a lens assembly suitable for a specific application such as an endoscope so as to form an endoscope with a smaller size.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that a miniature lens subassembly and camera module are provided to the imaging device of the smaller size of adaptation forms the camera module of smaller size.

In order to solve the above problem, the utility model provides a miniature lens subassembly, include: a single lens, said lens being a single-sided aspherical lens having opposing first and second surfaces, said first surface being planar and said second surface being curved; the first surface of the lens is square, and the side length is 0.5 mm.

Optionally, the method further includes: a cylindrical housing, said lens being disposed within said housing; silica gel is filled between the shell and the lens.

Optionally, the housing is a medical stainless steel housing.

Optionally, the diameter of the cylindrical housing is 0.9 mm.

Optionally, the maximum distance between the second surface and the first surface of the lens is 0.6 mm.

Optionally, the field angle of the lens is 90 to 105 degrees, the F value is 4, and the depth of field is 1.6mm to infinity.

Optionally, the second surface of the lens is coated with a filter film, and the wavelength which can be transmitted through the filter film is 435nm to 656 nm.

The technical scheme of the utility model a camera module is still provided, include: the miniature lens assembly as claimed in any one of the above items; the imaging device comprises a glass substrate and an optical sensor, wherein the glass substrate is arranged above a light sensing surface of the optical sensor; the first surface of the lens of the miniature lens assembly faces the glass substrate and is fixedly arranged.

Optionally, a surface of one side of the imaging device, which faces the lens assembly, is square, and the side length is 0.5 mm.

Optionally, the optical sensor is a CMOS sensor, the CMOS sensor includes 416416 pixel units, the pixel units are distributed in an array form, 214 pixel units are distributed in each row and each column, and each pixel unit is a square with a side length of 1.7 μm.

The utility model discloses a lens subassembly adopts the monolithic lens, satisfies the demand of simple and easy and reliable installation under the prerequisite of sacrificing partial optical property, realizes the small-size of lens subassembly to the smaller-size imaging device of adaptation reduces the size of camera module.

Drawings

Fig. 1 is a schematic structural diagram of a miniature camera module according to an embodiment of the present invention;

fig. 2a and 2b are schematic structural diagrams of a lens assembly of a micro camera module according to an embodiment of the present invention;

fig. 3a and 3b are schematic structural diagrams of a micro camera module according to an embodiment of the present invention.

Fig. 4 is a schematic structural diagram of an imaging device of a miniature camera module according to an embodiment of the present invention;

fig. 5 is a bottom schematic view of an imaging device of a miniature camera module according to an embodiment of the present invention;

fig. 6a and 6b are schematic structural diagrams of the core wire of the miniature camera module 4 according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a micro camera module according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a micro camera module according to an embodiment of the present invention.

Detailed Description

The following describes in detail a specific embodiment of the miniature camera module according to the present invention with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a camera module of an endoscope according to an embodiment of the present invention.

In this embodiment, the miniature camera module includes a lens assembly 101 and an imaging device 102.

In this embodiment, as shown in fig. 1, the size of the lens assembly 101 is 0.5mm × 0.5mm × 0.6.6 mm, the size of the imaging device 102 is 0.5mm × 0.5mm × 0.42.42 mm, which are the maximum sizes in three directions, respectively, and the lens assembly 101 and the imaging device 102 are represented by cubes in fig. 1, but in actual products, the lens assembly 101 and the imaging device 102 may have other shapes.

The lens assembly 101 is connected opposite to the imaging assembly 102 to form a camera module with the size of 0.5mm × 0.5.5 mm × 1.02.02 mm, and the camera module can be used for equipment such as a vascular endoscope and the like with strict requirements on the size of a camera.

Please refer to fig. 2a and fig. 2b, which are schematic structural views of a lens assembly according to an embodiment of the present invention, wherein fig. 2a is a front view, and fig. 2b is a side view.

In this specific embodiment, the lens assembly 101 includes a single lens 201, the lens 201 is a single-sided aspheric lens, the lens 201 has a first surface 2011 and a second surface 2012 opposite to the first surface 2011, the first surface 2011 is a plane, and the second surface 2012 is a curved surface. Compared with a lens assembly with multiple lenses, the lens assembly 101 adopts a single lens, meets the requirements of simple and reliable installation on the premise of sacrificing partial optical performance, and realizes the small size of the lens assembly.

In this embodiment, the bottom surface (i.e., the first surface 2011) of the lens 201 is square, and has a side length of 0.5mm, which corresponds to the size of the imaging device 102.

In this embodiment, the lens assembly 101, that is, the lens 201, has a field angle of 90 ° to 105 °, an F value of 4, and a depth of field of 1.6mm to infinity, and the front end of the lens 201 may be further provided with a filter, or the second surface 2012 of the lens 201 may be further coated with a filter so that the wavelength that can pass therethrough is 435nm to 656 nm.

In other specific embodiments, the size of the lens is adjusted by adopting a single-lens design, so that a lens module with a smaller size or a larger size can be obtained according to a specific use scene. The size of the imaging device 102 corresponds to the size of the lens assembly 101.

Please refer to fig. 3a and fig. 3b, which are schematic structural diagrams of a micro camera module according to an embodiment of the present invention. Fig. 3a is a front view and fig. 3b is a schematic sectional view along the cut line a-a' in fig. 3 a.

The lens assembly 101 is disposed in a cylindrical housing 801, and a silicone 202 is filled between the housing 801 and the lens assembly 101. The housing 801 may be made of medical grade stainless steel. In this embodiment, the cylindrical housing 801 has a diameter of 0.9mm, and the diameter of the housing 801 is reduced as much as possible while the lens unit 101 can be accommodated therein. Because the sides of the lens assembly 101 and the imaging device 102 are rectangular, a gap is formed between the lens assembly and the housing 801, and the gap is filled with the silica gel 802 to play a role in fixing and provide physical support. Meanwhile, the lens assembly 101 is located in the housing 801, the second surface of the lens 201 of the lens assembly 101 faces the light incidence direction, the side surface is shielded by the housing 801, and the housing 801 can be used as an optical light shield to shield the light incident from the side surface, so as to avoid causing interference to the imaging system.

In this embodiment, the imaging device 102 is also disposed in the cylindrical housing 801 to improve the connection reliability between the imaging device 102 and the lens assembly 101.

Fig. 4 is a schematic structural diagram of an imaging device according to an embodiment of the present invention.

In this embodiment, the imaging device 102 adopts an advanced Through Silicon Via (TSV) technology and a BGA packaging technology, so as to have a TSV structure and a BGA packaging structure.

In this embodiment, the imaging device 102 includes a glass substrate 301 and an optical sensor 302. The glass substrate 301 is disposed above the light-sensitive surface of the optical sensor 302, and the lens assembly 101 is fixed on the surface of the glass substrate 301 and opposite to the light-sensitive surface of the optical sensor 302. The first surface 1021 of the lens 102 of the miniature lens assembly 101 is fixedly disposed toward the glass substrate 301.

In this embodiment, the optical sensor 302 is a CMOS sensor. The optical sensor comprises a substrate 302 and a device layer 3022 formed on the front surface of the substrate 3021. A pixel array 3023 is formed on the surface of the device layer 3022. The device layer 3022 is fixedly attached to the glass substrate 301 via a support layer 3024, and the support layer 3024 is disposed around the pixel array 3023.

A circuit structure (not shown) connected to the pixel array 3023 is also formed in the device layer 3022 of the optical sensor 302. The circuit structure is connected to a pad 3026 formed on the back side of the substrate 3021 through a conductive via 3025 that extends through the substrate 3021. The back surface of the substrate 3021 is further covered with a protective layer 3027, and the protective layer 3027 has an opening to expose the pad 3026.

The imaging device 102 further includes a package substrate (not shown) connected to the optical sensor 302 and a package casing covering the package substrate and the side of the optical sensor 302. The package substrate is a circuit board, and a BGA (Ball Grid Array) packaging process is used to electrically connect the pad 3026 of the optical sensor 302 and the signal output terminal of the package substrate via a solder Ball Array. The BGA is a mature packaging process, and the specific structure is not described in detail. An analog video interface is formed in the packaging substrate and used for outputting analog video signals.

In this embodiment, the pixel array 3023 of the optical sensor 302 is distributed in an array form, 214 pixel units are distributed in each row and each column, 214 × 214 is 416416 pixel units, and each pixel unit is a square with a side of 1.7 μm.

In this embodiment, 2 × 2 pixel cells located at each corner of pixel array 3023 are used as dark pixels for black scaling.

The optical sensor 302 is also integrated with an internal imaging system control logic circuit, can provide an image output frequency of more than 60FPS (frames per second), can be applied to high-speed shooting occasions, and simultaneously supports an image output frequency of more than 120FPS (Range of interest). And, the image output signal-to-noise ratio is as high as 37dB or more.

The output end of the imaging device 102 is connected to the analog video interface through a 4-core cable, and is configured to output a video signal through the analog video interface. Compared with the prior art, the video signal output device has the advantages that the transmission modes such as the USB, the SDI and the AHD are adopted, the video signal output is carried out in the mode that the analog video interface and the 4 chips are connected, an external transmission device is not needed (the size of the external transmission device is usually larger than that of an imaging device), the effective transmission distance reaches 2 meters, and a convenient and easy-to-use interface is provided for a user.

Fig. 5 is a bottom schematic view of the imaging device 102.

The bottom of the imaging device 102 exposes four output ends of the back surface of the package substrate, namely 4 output ends of the analog video interface, which are respectively a clock end CCK, a power end VDD, a signal output end ASO and a ground end GND.

Please refer to fig. 6a and fig. 6b, which are schematic structural views of a 4-core wire according to an embodiment of the present invention, wherein fig. 6a is a schematic end view, and fig. 6b is a side view along a length direction.

In this embodiment, the 4-core wire is a 46AWG 4-core wire. Specifically, the 4 core wires include 4 inner core wires 503, a shielding layer 502 wrapping the 4 inner core wires 503 from inside to outside, and a shell 501 covering the shielding layer 502.

Each internal core wire 503 includes a wire 5031 and an insulating layer 5032 covering the wire 5031. The 4 inner core lines 503 of the 4 core lines are respectively connected to 4 output terminals (see fig. 5) of the imaging device 102, which are respectively a clock input line, a power supply line, a signal output line, and a ground signal line.

One end of the 4-core wire connected to the imaging device 102 is exposed with a part of the length of the wire 5031, the end of the conductive 5031 is formed with a solder ball 504 soldered to the imaging device 102, the exposed wire 5031 and the solder ball 504 have a length a, and the distance between the edge of the 4-core wire shell 501 and the edge of the insulating layer 5032 is a length B. In this embodiment, the length A is in the range of 0.15mm to 0.2mm, and the length B is in the range of 0.5mm to 1 mm.

The other end of the 4-core wire is used for connection to a video receiving end, also exposing a portion of the length of wire 5031 and the dielectric layer 5032. Wherein the exposed wires 5031 have a length D and the distance between the edge of the housing 501 and the edge of the dielectric layer 5032 is length C. In this embodiment, the length D is in the range of 1mm, and the length C is in the range of 10mm to 20 mm.

Please refer to fig. 7, which is a schematic structural diagram of a camera module according to another embodiment of the present invention.

Each of the inner core wires of the 4 core wires is connected to the output terminal of the imaging device 102 by a soldering process, such as reflow soldering of the solder ball 504 (see fig. 6), to form a solder joint 504a, and the wires 5031 at the solder joint 504a which are not covered by the insulating layer 5032 are covered by solder 503 a; the distance between adjacent welding points 504a is 0.1 ~ 0.2mm, the maximum diameter of welding point 504a is less than or equal to 0.13 mm.

Since the size of the output end of the imaging device 102 is also small, the size of the bonding pad and the distance between adjacent bonding pads need to be strictly controlled, so as to avoid the problems of short circuit between signal lines, etc.

Please refer to fig. 8, which is a schematic structural diagram of a camera module according to another embodiment of the present invention.

In this embodiment, a protective case 701 is further included to cover a connection end of the 4-core wire and the imaging device 102. Specifically, the protective shell 701 covers the welding point 504a between the 4-core wire and the imaging device 102, the wire 5031, the insulating layer 5032, and the shell 501 of a part of the 4-core wire, so as to improve the connection reliability between the imaging device 102 and the 4-core wire. In this embodiment, the length of the protective shell 701 is 0.8mm to 1.3 mm.

The camera module is small in size, the requirement for the tiny size of the camera under specific precision is met, an imaging system control circuit is integrated in an imaging device of the camera module, the camera module can work only by providing a power supply and a clock, an interface is simple, research and development are easy, and the marketing period is short; the adoption of the analog video interface and the 4-core wire interface provides a convenient and easy-to-use interface for users.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims

1. A miniature lens assembly, comprising:

a single lens, said lens being a single-sided aspherical lens having opposing first and second surfaces, said first surface being planar and said second surface being curved;

the first surface of the lens is square, and the side length is 0.5 mm.

2. The miniature lens assembly of claim 1, further comprising: a cylindrical housing, said lens being disposed within said housing; silica gel is filled between the shell and the lens.

3. The miniature lens assembly of claim 2, wherein the housing is a medical stainless steel housing.

4. The miniature lens assembly of claim 2, wherein the cylindrical housing has a diameter of 0.9 mm.

5. The miniature lens assembly of claim 1, wherein the maximum distance between the second surface and the first surface of the lens is 0.6 mm.

6. The miniature lens assembly of claim 1, wherein the lens has a field angle of 90 ° -105 °, an F-number of 4, and a depth of field of 1.6 mm-infinity.

7. The miniature lens assembly of claim 1, wherein the second surface of the lens is coated with a filter coating that is transparent at wavelengths between 435nm and 656 nm.

8. A camera module, comprising:

the miniature lens assembly of any one of claims 1 to 7;

the imaging device comprises a glass substrate and an optical sensor, wherein the glass substrate is arranged above a light sensing surface of the optical sensor;

the first surface of the lens of the miniature lens assembly faces the glass substrate and is fixedly arranged.

9. The camera module of claim 8, wherein a surface of the imaging device facing the lens assembly is square and has a side length of 0.5 mm.

10. The camera module of claim 8, wherein the optical sensor is a CMOS sensor, the CMOS sensor comprises 416416 pixel cells distributed in an array, each row and each column having 214 pixel cells, each pixel cell being a square with a side of 1.7 μm.