Cylindrical structure image sensor and control method, manufacturing method thereof
By designing a cylindrical image sensor and using a driving module to adjust the curvature of the flexible image sensing module, the problem of poor applicability of curved image sensors was solved, achieving multi-scene adaptation and high-quality imaging.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- QIANYUAN NATIONAL LABORATORY
- Filing Date
- 2026-03-24
- Publication Date
- 2026-06-16
AI Technical Summary
Existing curved image sensors have poor applicability and cannot meet the needs of high-end imaging and multi-scene adaptation.
Design a cylindrical image sensor, including a flexible image sensing module, a flexible support module, and a driving module. The driving module controls the movement of the clamping unit and the moving unit, and adjusts the deformation of the flexible support unit to achieve the cylindrical curvature of the flexible image sensing module to adapt to different optical lenses and imaging scenarios.
It broadens the application range of image sensors, improves image quality, reduces the cost of replacing equipment for multi-scene adaptation, simplifies the design difficulty of optical systems, and avoids image blurring and increased aberrations.
Smart Images
Figure CN122227098A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of image sensing, and in particular to cylindrical structure image sensors and their control and fabrication methods. Background Technology
[0002] The application of curved image sensors and their supporting optical systems has undergone a long development cycle and has now reached a certain level of technological maturity. They can be applied to multiple fields such as security monitoring, medical imaging, automotive imaging, and consumer electronics. Compared with traditional planar image sensors, they can effectively improve the aberrations of the optical system and enhance imaging quality and light utilization.
[0003] In related technologies, by applying sensors with a certain radius of curvature to optical systems to design the entire lens array, compared with planar imaging systems, the size and mass of the optical system can be significantly reduced while maintaining the same image quality. Under the same design constraints, performance optimization can be achieved by significantly improving image quality and field of view, greatly simplifying the design of optical systems. However, optical systems built based on curved image sensors can only be adapted to optical lenses with specific curvature requirements, and cannot meet the practical application needs of high-end imaging and multi-scene adaptation.
[0004] There is currently no effective solution to the problem of poor applicability of curved surface image sensors in related technologies. Summary of the Invention
[0005] Therefore, it is necessary to provide a cylindrical structure image sensor and its control and fabrication methods that can solve the problem of poor applicability of curved surface image sensors, in order to address the above-mentioned technical problems.
[0006] In a first aspect, this embodiment provides a cylindrical structure image sensor, which includes: a flexible image sensing module, a flexible support module, and a driving module; the flexible support module includes a flexible bearing unit, a first clamping unit, a second clamping unit, and a moving unit; the flexible bearing unit is plate-shaped, having opposing first and second sides, as well as opposing top and bottom surfaces; the first clamping unit is connected to the first side of the flexible bearing unit, the second clamping unit is connected to the second side of the flexible bearing unit, the flexible image sensing module is attached to the top surface of the flexible bearing unit, and the moving unit is connected to the bottom surface of the flexible bearing unit; wherein,
[0007] The flexible image sensing module is used to convert optical signals into electrical signals;
[0008] The driving module is used to respond to the driving signal to control the first clamping unit and the second clamping unit to generate relative displacement in the horizontal direction, and / or control the moving unit to move in the vertical direction, so that the flexible bearing unit and the flexible image sensing module are deformed.
[0009] In some embodiments, the cylindrical structure image sensor further includes a control module connected to the drive module; wherein,
[0010] The control module is used to obtain the radius of curvature of the target cylindrical surface according to the curvature adjustment requirements of the flexible image sensing module, and to generate the driving signal according to the radius of curvature of the target cylindrical surface.
[0011] In some embodiments, the cylindrical structure image sensor further includes a curvature detection module; wherein,
[0012] The curvature detection module is used to acquire the actual cylindrical curvature radius of the flexible image sensing module.
[0013] In some embodiments, the cylindrical structure image sensor includes a curvature detection module and a control module, wherein the curvature detection module is connected to the control module;
[0014] The control module is used to obtain the target cylindrical radius of curvature according to the curvature adjustment requirements of the sensing image surface in the flexible image sensing module, compare the actual cylindrical radius of curvature with the target cylindrical radius of curvature, and generate the driving signal based on the comparison result.
[0015] In some embodiments, the flexible image sensing module includes: a flexible image sensing chip and a flexible circuit board, wherein the flexible image sensing chip is attached to the top surface of the flexible circuit board, and the flexible circuit board is attached to the top surface of the flexible support module; wherein,
[0016] The flexible image sensing chip is used to receive optical signals and convert the optical signals into electrical signals;
[0017] The flexible circuit board is used to process the electrical signals.
[0018] In some embodiments, the cylindrical image sensor further includes an image sensing driving module connected to the flexible circuit board; wherein,
[0019] The image sensing driving module is used to output driving signals to the flexible circuit board to drive the flexible image sensing chip connected to the flexible circuit board to operate; it is also used to receive and output electrical signals read from the flexible circuit board.
[0020] In some embodiments, the moving unit is connected to the geometric center of the bottom surface of the flexible support unit.
[0021] Secondly, this embodiment provides a control method for a cylindrical structure image sensor, applied to the cylindrical structure image sensor described in the first aspect above, the method comprising:
[0022] The radius of curvature of the target cylindrical surface is obtained based on the curvature adjustment requirements of the sensing image surface;
[0023] The first clamping unit and the second clamping unit in the cylindrical structure image sensor are controlled to generate relative displacement in the horizontal direction according to the target cylindrical surface curvature radius, and / or the moving unit in the cylindrical structure image sensor is controlled to move in the vertical direction, so that the flexible image sensing module attached to the flexible support unit in the cylindrical structure image sensor deforms.
[0024] Thirdly, this embodiment provides a method for fabricating a cylindrical structure image sensor, the method comprising:
[0025] The image sensor chip is thinned and then mounted onto a flexible circuit board.
[0026] The flexible circuit board is attached to the top surface of the flexible support unit, and the bottom surface of the flexible support unit is connected to the moving unit. The first side of the flexible support unit is connected to the first clamping unit, and the second side of the flexible support unit is connected to the second clamping unit. The flexible support unit is plate-shaped and has opposing first and second sides, as well as opposing top and bottom surfaces.
[0027] The driving module is connected to the first clamping unit, the second clamping unit, and the moving unit, so that under the drive of the driving module, the first clamping unit and the second clamping unit move in the horizontal direction, and the moving unit moves in the vertical direction.
[0028] Fourthly, this embodiment provides an optical system including the cylindrical image sensor described in the first aspect above.
[0029] The aforementioned cylindrical image sensor and its control and fabrication methods involve connecting a first clamping unit to the first side of a flexible support unit, a second clamping unit to the second side of the flexible support unit, attaching a flexible image sensing module to the top surface of the flexible support unit, and connecting a moving unit to the bottom surface of the flexible support unit. A driving module controls the movement of the first clamping unit, the second clamping unit, and the moving unit, causing the flexible support unit to deform. This, in turn, causes the flexible image sensing module attached to the flexible support unit to deform, achieving the effect of adjusting the cylindrical curvature of the cylindrical image sensor. This makes it possible for the cylindrical image sensor to match the image plane curvature requirements of different optical lenses and different imaging scenarios, thereby broadening the applicability of the cylindrical image sensor. Attached Figure Description
[0030] Figure 1 This is a schematic diagram of the structure of a cylindrical image sensor according to one embodiment of the present application;
[0031] Figure 2 A schematic diagram of the driving mechanism for a cylindrical structure image sensor provided in this application;
[0032] Figure 3 A schematic diagram of a second embodiment of a cylindrical image sensor provided in this application;
[0033] Figure 4 A flowchart illustrating a control method for a cylindrical structure image sensor provided in this application;
[0034] Figure 5 This is a schematic flowchart illustrating a method for fabricating a cylindrical image sensor provided in this application. Detailed Implementation
[0035] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.
[0036] Unless otherwise defined, the technical or scientific terms used in this application shall have the general meaning understood by one of ordinary skill in the art to which this application pertains. Words such as “a,” “an,” “an,” “the,” “the,” and “these” used in this application do not indicate quantitative limitation and may be singular or plural. The terms “comprising,” “including,” “having,” and any variations thereof used in this application are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or device that comprises a series of steps or modules (units) is not limited to the listed steps or modules (units) but may include steps or modules (units) not listed, or may include other steps or modules (units) inherent to these processes, methods, products, or devices. Words such as “connected,” “linked,” and “coupled” used in this application are not limited to physical or mechanical connections but may include electrical connections, whether direct or indirect. “Multiple” used in this application refers to two or more. “And / or” describes the relationship between related objects, indicating that three relationships may exist; for example, “A and / or B” can represent: A alone, A and B simultaneously, and B alone. Normally, the character " / " indicates that the objects before and after it are in an "or" relationship. The terms "first," "second," "third," etc., used in this application are merely to distinguish similar objects and do not represent a specific order of objects.
[0037] The following specific embodiments are given to illustrate the technical solution of this application in detail.
[0038] In one embodiment, Figure 1 A schematic diagram of a first embodiment of a cylindrical image sensor is provided, as shown below. Figure 1 As shown, the cylindrical structure image sensor includes: a flexible image sensing module, a flexible support module, and a driving module; the flexible support module includes a flexible bearing unit, a first clamping unit, a second clamping unit, and a moving unit; the flexible bearing unit is plate-shaped, having a first side and a second side, as well as a top surface and a bottom surface; the first clamping unit is connected to the first side of the flexible bearing unit, the second clamping unit is connected to the second side of the flexible bearing unit, the flexible image sensing module is attached to the top surface of the flexible bearing unit, and the moving unit is connected to the bottom surface of the flexible bearing unit.
[0039] A flexible image sensing module is used to convert optical signals into electrical signals.
[0040] The flexible image sensing module includes a flexible sensing chip and its readout circuit. Even under static or dynamic bending with a certain radius of curvature within a certain range, the flexible image sensing module still retains the ability to convert optical signals into electrical signals.
[0041] The driving module is used to respond to the driving signal to control the first clamping unit and the second clamping unit to generate relative displacement in the horizontal direction, and / or control the moving unit to move in the vertical direction, so that the flexible bearing unit and the flexible image sensing module are deformed.
[0042] The flexible support unit serves as the foundation for the flexible image sensing module and is constructed from a curved, deformable plate-like structure. Specifically, the flexible support unit can be made of materials with adaptable elasticity and thickness, such as ultra-thin glass, ultra-thin silicon wafers, flexible optical films, and rubber—materials with smooth surfaces, uniform thickness, and adaptable elasticity.
[0043] It should be understood that the elastic modulus varies depending on the material used for the flexible load-bearing unit. The material of the flexible load-bearing unit can be selected and adjusted according to the bending requirements of the cylindrical structure image sensor. In addition, mechanical stiffness is not only related to the elastic modulus, but also inversely proportional to the cube of the thickness. Therefore, the thickness of the flexible load-bearing unit can also be adjusted according to the bending requirements of the cylindrical structure image sensor.
[0044] The first and second clamping units are used to clamp the flexible support unit from both sides. The first and second sides can be the left and right sides of the flexible support unit, or the front and rear sides, without limitation. The first and second clamping units can be rigid clamping structures, such as mechanical claw clamping structures, friction-based clamping structures, or adsorption clamping structures. Furthermore, depending on requirements, flexible cushioning materials, such as rubber pads or silicone layers, can be provided on the contact surfaces of the first and second clamping units. For example, the first and second clamping units ensure a flat clamping surface, providing complete fixation at both ends of the flexible support unit, and can correct and adjust the curvature morphology of the cylindrical image sensor through slight relative sliding.
[0045] The moving unit is used to apply vertical displacement to the flexible support unit. The moving unit can be a mechanism with vertical lifting capabilities, such as a liftable push rod or bracket. The moving unit can be connected to the bottom surface of the flexible support unit through methods such as adsorption, bonding, or fitting.
[0046] The drive module is connected to the first clamping unit, the second clamping unit, and the moving module, respectively. Exemplarily, the drive module includes multiple actuators, each connected to the first clamping unit, the second clamping unit, and the moving module. These actuators, in response to drive signals, can independently control the two horizontal clamping units to move towards or away from each other, independently control the vertical moving unit to move up and down, or coordinate the synchronous movement of all three, thereby achieving complex deformation path control. The actuators can be servo motors, linear motors, etc., and the type of actuator in the drive module is not limited here. The drive signal can be a signal generated based on a preset program or a signal applied externally in real time.
[0047] In response to the driving signal, the driving module controls the first clamping unit and the second clamping unit to generate relative displacement in the horizontal direction, and / or controls the moving unit to move in the vertical direction. Under the action of the driving module, the flexible bearing unit undergoes controllable deformation, and drives the flexible image sensing module attached to the flexible bearing unit to form a cylindrical structure with different curvatures to adapt to different application scenarios.
[0048] Specifically, since the flexible image sensing module is attached to the top surface of the flexible support unit, meaning its placement direction is perpendicular to the bending axis of the flexible support unit, when the flexible support unit deforms, the flexible image sensing module attached to it also deforms, and the flexible image sensing module is only subjected to stretching or compression in one dimension during bending. For ease of understanding, Figure 2 A schematic diagram of the driving mechanism for a cylindrical image sensor is provided, such as... Figure 2 As shown, under the control of the drive module, the cylindrical image sensor structure is precisely controlled by using a fixed support with clamping units at both ends and a pushing mechanism with a bottom moving unit. This allows the flexible support unit of the cylindrical image sensor to deform synchronously with the flexible image sensing module. The flexible support unit bends only in one direction (cylindrical direction) while remaining straight in the other direction (generatrix direction), achieving a pure bending deformation effect without stretching. This avoids tensile stress damage to the flexible image sensing module.
[0049] The aforementioned cylindrical image sensor, by attaching a flexible image sensing module to the top surface of a flexible support unit and controlling the movement of the first clamping unit, the second clamping unit, and the moving unit by the drive module, causes the flexible support unit to deform, thereby adjusting the cylindrical curvature of the flexible image sensing module. In this way, the cylindrical image sensor can match the image plane curvature requirements of different optical lenses and different imaging scenarios, thus broadening the application range of the cylindrical image sensor.
[0050] In addition, by adjusting the cylindrical curvature of the cylindrical structure image sensor, problems such as imaging blurring, increased aberration, and vignetting can be effectively avoided, improving the imaging quality of the optical imaging system; moreover, the equipment replacement cost during multi-scenario adaptation can be reduced, and the design difficulty of the optical system including the cylindrical structure image sensor can be simplified.
[0051] The cylindrical structure image sensor in this embodiment can be widely applied to small imaging devices (such as consumer electronics and vehicle-mounted lenses), large optical systems (such as astronomical telescopes), and high-end imaging scenarios (such as medical imaging and security monitoring); the above application scenarios are only for illustration and not for limitation.
[0052] In one of the implementation manners, the cylindrical structure image sensor further includes a control module, and the control module is connected to the driving module; wherein, the control module is used to obtain the target cylindrical curvature radius according to the curvature adjustment requirement of the flexible image sensing module, and generate a driving signal according to the target cylindrical curvature radius.
[0053] Among them, the curvature requirement refers to the bending curvature that the sensing image plane in the flexible image sensing module needs to reach, and its value can be obtained based on the focal plane curvature of one or more lenses supporting the flexible image sensing module. Optionally, obtain the focal plane curvature of the lens; through a preset matching relationship, match the bending curvature of the sensing image plane in the flexible image sensing module according to the focal plane curvature of the lens. When the focal plane curvature of the lens matches the bending curvature of the sensing image plane, the aberration can be significantly reduced, and the imaging quality and range can be improved; the matching relationship between the two can be set according to the application requirements of the lens.
[0054] The control module converts the bending curvature required by the sensing image plane into the target cylindrical curvature radius; and calculates the displacement value of at least one of the first clamping unit, the second clamping unit, and the moving unit based on the target cylindrical curvature radius, and then generates a driving signal based on this displacement value, so that the curvature radius of the deformed flexible bearing unit is equal to the cylindrical curvature radius.
[0055] Among them, parameters such as the moving order and moving speed of each unit indicated by the driving signal can be configured according to requirements. For example, the first clamping unit, the second clamping unit, and the moving unit can be moved simultaneously; or the above units can be moved based on a preset order. The mapping relationship between the bending curvature and the cylindrical curvature radius, and how to generate the corresponding driving signal based on the displacement amount specifically, can be referred to the description in the related technology and will not be elaborated here.
[0056] In this embodiment, the control module automatically generates a driving signal according to the curvature adjustment requirement of the sensing image plane, eliminating human error and improving the optical performance.
[0057] In one embodiment, the cylindrical structure image sensor further includes a curvature detection module; wherein the curvature detection module is used to acquire the actual cylindrical curvature radius of the flexible image sensing module.
[0058] The curvature detection module can utilize a contact-type flexible sensor, which is attached to the surface of the flexible support unit or the flexible image sensing module. The actual cylindrical curvature radius is obtained by real-time feedback of the collected deformation signals. Alternatively, the curvature detection module can employ an optical non-contact measurement device. For example, the curvature detection module directly acquires the topographic data of the cylindrical structure image sensor and calculates the actual cylindrical curvature radius of the flexible image sensing module.
[0059] In this embodiment, the curvature detection module can collect the actual cylindrical curvature radius of the flexible image sensing module to determine the actual shape of the current cylindrical structure image sensor.
[0060] Furthermore, in one embodiment, the cylindrical structure image sensor includes a curvature detection module and a control module, with the curvature detection module connected to the control module; the control module is used to obtain the target cylindrical curvature radius according to the curvature adjustment requirements of the sensing image surface in the flexible image sensing module, compare the actual cylindrical curvature radius with the target cylindrical curvature radius, and generate a driving signal based on the comparison result.
[0061] Optionally, the control module can calculate the displacement required for the flexible image sensing module to reach the target cylindrical radius of curvature based on the deviation between the actual and target cylindrical radius of curvature, using a built-in PID control algorithm or model predictive control algorithm. This displacement is then used to generate a corresponding drive signal. The specific implementation principles and methods of the PID control algorithm and model predictive control algorithm can be found in relevant technical documents.
[0062] In this embodiment, by connecting the curvature detection module and the control module, the control module can determine the degree of matching between the image plane shape of the current cylindrical structure image sensor and the focal plane of the lens by comparing the actual cylindrical curvature radius and the target cylindrical curvature radius. Based on the matching result, the bending degree of the flexible image sensing module attached to the top surface of the flexible support unit can be precisely adjusted.
[0063] In one embodiment, the flexible image sensing module includes a flexible image sensing chip and a flexible circuit board, wherein the flexible image sensing chip is attached to the top surface of the flexible circuit board, and the flexible circuit board is attached to the top surface of the flexible support module.
[0064] A flexible image sensor chip is used to receive optical signals and convert them into electrical signals. This flexible image sensor chip possesses excellent flexibility and deformation capability, allowing it to deform synchronously with the flexible circuit board and cylindrical support. The chip type can be CCD, CMOS, etc., making the flexible image sensor chip unaffected by front or back illumination constraints. For example, the flexible image sensor chip can be composed of an ultra-thin image sensor chip that has undergone thinning treatment, and can be attached to a reserved chip area on the flexible circuit board, with a thickness of approximately 15μm to 30μm.
[0065] A flexible circuit board is used to read electrical signals. This flexible circuit board can be made of a flexible insulating polymer film such as polyimide (PI) and is used to support a flexible image sensor chip. Specifically, the flexible circuit board includes a flexible readout circuit for reading signals from the flexible image sensor chip; surface-mount capacitors can also be placed on the flexible circuit board to suppress noise in high-frequency signals.
[0066] Furthermore, in one embodiment, the cylindrical structure image sensor further includes an image sensing drive module connected to a flexible circuit board; wherein the image sensing drive module is used to output drive signals to the flexible circuit board to drive the flexible image sensing chip connected to the flexible circuit board to operate; and is also used to receive and output electrical signals read from the flexible circuit board.
[0067] The driving signals include timing signals, bias voltage signals, and ground signals. In one embodiment, the cylindrical structure image sensor also includes a data connection line; Figure 3 A schematic diagram of a second embodiment of a cylindrical image sensor is provided, as shown below. Figure 3 As shown, the flexible image sensor chip is attached to the top surface of the flexible circuit board. The flexible circuit board has a reserved data interface for connection with the image processing module. The image sensor driving module is connected to the reserved data interface in the flexible circuit board via a data connection cable. The image sensor driving module can be mounted on a rigid PCB and led out separately by the data connection cable. The data cable can be a flexible flat cable or an ultra-fine coaxial cable.
[0068] When a cylindrical image sensor includes an image sensing drive module, the flexible circuit board is also used to receive the drive signal output by the image sensing drive module and load the drive signal onto the flexible image sensing chip so that the flexible image sensing chip works under the drive of the image sensing drive module.
[0069] After the flexible image sensor chip is in operation, it generates MIPI signals in response to different light intensities. The MIPI signals are transmitted to the image sensor driving module through the flexible readout circuit. The image sensor driving module can then read the signals and import them into an external terminal to obtain an image.
[0070] In one embodiment, the moving unit is connected to the geometric center of the bottom surface of the flexible support unit. By mounting the moving unit at the center of the back surface of the substrate, the moving unit can achieve single-point pushing of the flexible support unit's center; that is, the moving unit pushes upward to form a convex cylindrical surface on the upper surface of the substrate and pulls downward to form a concave cylindrical surface. Optionally, the moving unit can also be equipped with a micrometer or displacement sensor to continuously monitor the position of the moving unit. The micrometer or displacement sensor ensures precise control of the vertical displacement of the moving unit, providing accurate support for curvature adjustment.
[0071] Based on the same inventive concept, this application also provides a control method for the above-mentioned cylindrical structure image sensor.
[0072] In one embodiment, such as Figure 4 The diagram shows a flowchart illustrating a control method for a cylindrical structure image sensor, comprising:
[0073] S401, obtain the radius of curvature of the target cylindrical surface according to the curvature adjustment requirements of the sensing image surface;
[0074] S402, the first and second clamping units in the cylindrical structure image sensor are controlled to move horizontally and / or the moving unit in the cylindrical structure image sensor is controlled to move vertically according to the radius of curvature of the target cylindrical surface, so that the flexible image sensing module attached to the flexible support unit in the cylindrical structure image sensor deforms. The cylindrical structure image sensor is the sensor in any of the above embodiments.
[0075] Specifically, by changing the vertical displacement h of the moving unit, the cylindrical curvature radius R of the flexible support unit can be adjusted. Under small deformation, the cylindrical curvature radius can be obtained using the approximate formula: R≈L² / 8h; where L is the effective length of the flexible support unit between the first and second clamping units. Optionally, the cylindrical curvature radius of the cylindrical structure image sensor is set according to the lens matched to the cylindrical structure image sensor.
[0076] Optionally, the control method for the cylindrical structure image sensor further includes: acquiring the actual cylindrical curvature radius of the flexible image sensing module, comparing the actual cylindrical curvature radius with the target cylindrical curvature radius, driving the first clamping unit and the second clamping unit to generate relative displacement in the horizontal direction based on the comparison result, and / or driving the moving unit to move in the vertical direction.
[0077] By controlling the first clamping unit and the second clamping unit, and / or the moving unit, the optimal image plane matching of the lens is achieved, ensuring that the cylindrical structure image sensor produces clear images without significant aberrations and with precise curvature adjustment, thereby achieving the best image plane matching for wide-angle imaging.
[0078] The specific limitations of the cylindrical structure image sensor used in this embodiment can be found in the limitations described above in the sensor embodiment, and will not be repeated here.
[0079] Based on the same inventive concept, this application also provides a method for fabricating the above-mentioned cylindrical structure image sensor. In one embodiment, such as Figure 5 The diagram shows a flowchart illustrating a method for fabricating a cylindrical image sensor, including:
[0080] S501 thins the image sensor chip and mounts the thinned image sensor chip onto a flexible circuit board.
[0081] One approach is to use existing thinning methods to process image sensor chips, resulting in flexible image sensor chips. Taking mechanical grinding as an example, the silicon wafer of the image sensor is thinned. During this process, a grinding wheel composed of diamond particles moves relative to the wafer tray at a certain rotational speed and descent rate. The diamond grinding wheel and the tray fixture rotate counter-clockwise around their own axes, with the edge of the grinding wheel coinciding with the axis of the tray. The diamond abrasive particles perform dynamic physical friction on the wafer surface, removing material. To maintain sufficient flexibility, the thickness of the ground chip should be in the range of 20μm to 30μm.
[0082] For example, the mechanical grinding method specifically includes four steps:
[0083] (1) Spin-coating a polyimide film onto the front of the image sensor chip to protect the chip's functional layer and prevent damage to the image sensor chip during the thinning process;
[0084] (2) Use diamond grinding wheels to directly thin and polish the image sensor chip wafer, and use small-particle diamond to grind the back of the image sensor wafer to reduce damage to the wafer surface.
[0085] (3) After the thinning process, the ultrathin wafer is fixed on the blue film, and the wafer is converted into a single-chip array using the dicing process;
[0086] (4) Ultraviolet light reduces the interfacial adhesion between the image sensor chip and the blue film, forcing the image sensor chip to completely separate from the blue film. Then, a suction cup is used to pick it up and place it on the flexible circuit board substrate.
[0087] For example, the flexible circuit board is made of polyimide (PI) material, and an image sensor chip area and corresponding solder pads are reserved in the flexible circuit board to realize the soldering of the image sensor chip.
[0088] In one embodiment, the cylindrical image sensor further includes an image sensing drive module. Thus, a data interface can be reserved in the flexible circuit board, and a flexible flat cable or ultra-fine coaxial cable can be used to connect the reserved interface to the image sensing drive module. Optionally, reinforcement can be provided at the interface location to ensure that repeated bending will not damage the interface.
[0089] In one embodiment, after the image sensor chip is thinned, a die-bonding film is attached to the bottom of the chip. The chip is then placed on the pre-reserved sensor chip area of the flexible circuit board, weighed down with a weight, and placed in an oven heated to 140°C for 45 minutes to ensure the ultra-thin image sensor chip is tightly bonded to the flexible circuit board. Gold wire bonding is then performed: the chip pads are connected to the flexible circuit board pads using gold ball bonding, with gold wires laid flat on the surface of the flexible circuit board. Finally, silicone is applied over the chip pads, gold wires, and flexible circuit board pads, ensuring complete coverage and completing the flexible encapsulation to obtain the aforementioned flexible image sensing module.
[0090] S502, a flexible circuit board is attached to the top surface of the flexible support unit, and the bottom surface of the flexible support unit is connected to the moving unit. The first side of the flexible support unit is connected to the first clamping unit, and the second side of the flexible support unit is connected to the second clamping unit. The flexible support unit is plate-shaped and has opposite first and second sides, as well as opposite top and bottom surfaces.
[0091] The flexible support unit can be made of board material with suitable elasticity and thickness. Optionally, the substrate surface of the flexible circuit board is cleaned and polished, and then the flexible circuit board is attached to the adjustment structure using an adhesive solution, ensuring uniform adhesion, no air bubbles, no internal stress, and that the long side of the image sensor chip remains parallel to the generatrix of the cylinder. Here, the cylinder refers to the convex cylinder formed by the upward deformation of the flexible support unit when the moving unit pushes, or the concave cylinder formed by the downward deformation.
[0092] S503, the drive module is connected to the first clamping unit, the second clamping unit, and the moving unit, so that under the drive of the drive module, the first clamping unit and the second clamping unit move in the horizontal direction and the moving unit moves in the vertical direction.
[0093] In one embodiment, the cylindrical structure image sensor further includes a control module connected to the drive module, and the control module outputs a drive signal to the drive module. Optionally, the cylindrical structure image sensor further includes a curvature detection module connected to the control module, such that the control module combines the cylindrical curvature radius output by the curvature detection module to output the drive signal. The control module and drive module, and the curvature detection module and control module, can be connected via a digital bus, I / O port, or other means.
[0094] In this embodiment, relying on chip thinning technology, a flexible image sensor chip is obtained while retaining the chip's extremely high pixel density. Simultaneously, by combining flexible support units, flexible circuit boards, and other structures, a cylindrical image sensor is constructed. This allows the cylindrical image sensor to balance flexible deformation capability with circuit stability and good compatibility with traditional silicon-based processes. Furthermore, the aforementioned fabrication process is standardized, highly operable, and easy to scale up for mass production, thereby improving production efficiency.
[0095] For specific limitations in the above-described embodiments of the method for fabricating cylindrical image sensors, please refer to the limitations of the cylindrical image sensor embodiments described above, which will not be repeated here.
[0096] In one embodiment, an optical system is also provided, including the cylindrical image sensor described in any of the above embodiments. By configuring a cylindrical image sensor with adjustable curvature in the optical system, the equipment replacement cost when adapting the optical system to multiple scenarios can be reduced, the design difficulty of the optical system can be simplified, the number of lenses and the types of materials used in the optical lens can be reduced, thereby reducing the manufacturing difficulty and production cost of the entire optical imaging system.
[0097] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments described above. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, etc., and are not limited to these.
[0098] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
[0099] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.
Claims
1. A cylindrical image sensor, characterized in that, The cylindrical image sensor includes: a flexible image sensing module, a flexible support module, and a driving module; the flexible support module includes a flexible bearing unit, a first clamping unit, a second clamping unit, and a moving unit; the flexible bearing unit is plate-shaped, having opposing first and second sides, as well as opposing top and bottom surfaces; the first clamping unit is connected to the first side of the flexible bearing unit, the second clamping unit is connected to the second side of the flexible bearing unit, the flexible image sensing module is attached to the top surface of the flexible bearing unit, and the moving unit is connected to the bottom surface of the flexible bearing unit; wherein... The flexible image sensing module is used to convert optical signals into electrical signals; The driving module is used to respond to the driving signal to control the first clamping unit and the second clamping unit to generate relative displacement in the horizontal direction, and / or control the moving unit to move in the vertical direction, so that the flexible bearing unit and the flexible image sensing module are deformed.
2. The cylindrical structure image sensor according to claim 1, characterized in that, The cylindrical structure image sensor also includes a control module, which is connected to the drive module; wherein... The control module is used to obtain the radius of curvature of the target cylindrical surface according to the curvature adjustment requirements of the flexible image sensing module, and to generate the driving signal according to the radius of curvature of the target cylindrical surface.
3. The cylindrical structure image sensor according to claim 1 or 2, characterized in that, The cylindrical structure image sensor also includes a curvature detection module; wherein... The curvature detection module is used to acquire the actual cylindrical curvature radius of the flexible image sensing module.
4. The cylindrical structure image sensor according to claim 3, characterized in that, The cylindrical structure image sensor includes a curvature detection module and a control module, wherein the curvature detection module is connected to the control module; wherein... The control module is used to obtain the target cylindrical radius of curvature according to the curvature adjustment requirements of the sensing image surface in the flexible image sensing module, compare the actual cylindrical radius of curvature with the target cylindrical radius of curvature, and generate the driving signal based on the comparison result.
5. The cylindrical structure image sensor according to claim 1, characterized in that, The flexible image sensing module includes: a flexible image sensing chip and a flexible circuit board. The flexible image sensing chip is attached to the top surface of the flexible circuit board, and the flexible circuit board is attached to the top surface of the flexible support module; wherein, The flexible image sensing chip is used to receive optical signals and convert the optical signals into electrical signals; The flexible circuit board is used to process the electrical signals.
6. The cylindrical structure image sensor according to claim 5, characterized in that, The cylindrical image sensor further includes an image sensing driving module, which is connected to the flexible circuit board; wherein... The image sensing driving module is used to output driving signals to the flexible circuit board to drive the flexible image sensing chip connected to the flexible circuit board to operate; it is also used to receive and output electrical signals read from the flexible circuit board.
7. The cylindrical structure image sensor according to claim 1, characterized in that, The moving unit is connected to the geometric center of the bottom surface of the flexible support unit.
8. A control method for a cylindrical structure image sensor, characterized in that, The method, applied to the cylindrical structure image sensor according to any one of claims 1 to 7, comprises: The radius of curvature of the target cylindrical surface is obtained based on the curvature adjustment requirements of the sensing image surface; The first clamping unit and the second clamping unit in the cylindrical structure image sensor are controlled to generate relative displacement in the horizontal direction according to the target cylindrical surface curvature radius, and / or the moving unit in the cylindrical structure image sensor is controlled to move in the vertical direction, so that the flexible image sensing module attached to the flexible support unit in the cylindrical structure image sensor deforms.
9. A method for fabricating a cylindrical image sensor, characterized in that, The method includes: The image sensor chip is thinned and then mounted onto a flexible circuit board. The flexible circuit board is attached to the top surface of the flexible support unit, and the bottom surface of the flexible support unit is connected to the moving unit. The first side of the flexible support unit is connected to the first clamping unit, and the second side of the flexible support unit is connected to the second clamping unit. The flexible support unit is plate-shaped and has opposing first and second sides, as well as opposing top and bottom surfaces. The driving module is connected to the first clamping unit, the second clamping unit, and the moving unit, so that under the drive of the driving module, the first clamping unit and the second clamping unit move in the horizontal direction, and the moving unit moves in the vertical direction.
10. An optical system, characterized in that, The cylindrical structure image sensor includes any one of claims 1 to 7.