Periscopic long-focus camera module

Abstract

The utility model relates to the field of optical imaging, and discloses a periscopic long-focus camera module, which comprises a bracket, a prism assembly which is arranged on the bracket and is provided with a first incident plane and a first emergent plane, a lens assembly which is arranged on the bracket and is over against the first incident plane, and an image processing assembly, the prism assembly comprises a first prism installed on the support and a second prism installed on the first prism, and a composite film system structure is arranged between the first prism and the second prism. The first prism and the second prism are compounded to effectively prolong the focal length without increasing the height of the prism assembly, so that the whole structure is more compact, light and thin, the composite film system structure is arranged between the first prism and the second prism, the gradient refractive index is deposited while the connection of the first prism and the second prism is ensured, and the resolution of the prism assembly is improved. The optical performance is optimized, the overall performance of the optical system is effectively improved, the light inlet amount and image quality details are enhanced, and the requirement of consumers for high-quality imaging is met.

Description

Technical Field

[0001] This utility model relates to the field of optical imaging, and in particular to a periscope telephoto camera module. Background Technology

[0002] With the widespread adoption of smart electronic devices, people's reliance on mobile phones in daily life is constantly increasing, especially in terms of communication and camera functions. To meet consumers' demands for mobile phone photography performance, the application of telephoto lenses in mobile phones is growing. Traditional optical zoom technology achieves zoom by moving lens components; however, this method has many limitations when applied to mobile phones. Due to the limited internal space of mobile phones, it is difficult to accommodate traditional large-sized lens components, resulting in poor shooting effects and failing to meet consumers' demands for high magnification. To overcome these limitations, periscope lenses have emerged. By introducing a prism into the lens imaging system, periscope lenses can extend the focal length without increasing the thickness of the mobile phone, supporting larger sensors, thereby enhancing light intake and image detail. However, existing periscope lenses still have some problems. While ensuring performance indicators, existing periscope lens modules have not fully optimized the height and width of the lens module, affecting the overall design compactness. Traditional glass total internal reflection prisms are easily damaged, requiring additional protective measures, increasing manufacturing costs and usage risks. Utility Model Content

[0003] In view of the shortcomings of the prior art, the technical problem to be solved by this utility model is to provide a periscope telephoto camera module to solve the problem of poor image quality and appearance caused by the difficulty in achieving high-magnification optical zoom without increasing the thickness of the mobile phone.

[0004] To solve the above-mentioned technical problems, the present invention provides a periscope telephoto camera module including a bracket, a prism assembly mounted on the bracket and having a first incident surface and a first exit surface, a lens assembly mounted on the bracket and facing the first incident surface, and an image processing assembly; the prism assembly includes a first prism mounted on the bracket and having a first incident surface and a second prism mounted on the first prism and having a first exit surface, and a composite film structure is provided between the first prism and the second prism to stack and connect the first prism and the second prism and extend the focal length.

[0005] Furthermore, the composite film structure sequentially includes a high refractive index layer with a refractive index of nd1, a medium refractive index layer with a refractive index of nd2, and a low refractive index layer with a refractive index of nd3, where nd1 > nd2 > nd3. The high refractive index layer is attached to the second exit surface, and the low refractive index layer is attached to the second incident surface.

[0006] Furthermore, the thicknesses of the high refractive index layer, the medium refractive index layer, and the low refractive index layer are t1, t2, and t3, respectively, where t1 + t2 + t3 = λ / 4, and λ is the wavelength of the incident light.

[0007] Furthermore, the first prism also has a first reflecting surface and a second exiting surface. After entering the first prism from the first incident surface, light is sequentially directed toward the first reflecting surface and the second exiting surface. The second prism also has a second incident surface and a second reflecting surface. A composite film structure is formed between the second exiting surface and the second incident surface. After being directed toward the second exiting surface, light is sequentially directed toward the composite film structure, the second reflecting surface, and the first exiting surface before being directed toward the image processing component.

[0008] Furthermore, the first prism is configured as a triangular prism, with a first incident surface, a first reflecting surface, and a first exiting surface distributed sequentially; the second prism is configured as a trapezoidal prism, with the second incident surface and the first exiting surface located on the same side, and the second prism also includes a third reflecting surface on the same side as the second incident surface and a fourth reflecting surface symmetrically distributed with the second reflecting surface. Light passes sequentially through the first incident surface, the first reflecting surface, the second exiting surface, the composite film structure, the second incident surface, the second reflecting surface, the third reflecting surface, and the fourth reflecting surface before being directed toward the first exiting surface. The first incident surface is coaxially arranged with the lens.

[0009] Furthermore, the angle between the first incident surface and the first reflecting surface is 30°, and the angle between the second incident surface and the second reflecting surface is 45°.

[0010] Furthermore, the third reflecting surface and the first exiting surface are configured together as a mounting surface, and the image processing component is mounted on the mounting surface and abuts against the first prism.

[0011] Furthermore, a lens assembly is mounted on the mounting surface, and the image processing assembly is mounted on the side of the lens assembly facing away from the mounting surface.

[0012] Furthermore, the lens assembly includes a protective glass sheet, a light-emitting lens, and an anti-fog coating coated on the protective glass sheet. The anti-fog coating is close to the first emission surface, and the light-emitting lens is located on the side away from the first emission surface.

[0013] Furthermore, the bracket has a mating surface, on which a first mounting groove adapted to the second prism is recessed, and the second prism is installed in the first mounting groove; an extension is formed on the side of the mating surface corresponding to the second incident surface, and a second mounting groove adapted to the first prism and connected to the first mounting groove is recessed along the optical axis direction on the extension, and the first prism is installed in the second mounting groove; the second mounting groove passes through the side of the extension facing away from the first mounting groove along the optical axis direction to form a light inlet, and the lens assembly is installed on the side of the bracket with the light inlet and arranged directly opposite the first incident surface to the light inlet.

[0014] The periscope telephoto camera module of this invention has at least the following beneficial effects: by combining the first prism and the second prism, the focal length can be effectively extended without increasing the height of the prism assembly, making the entire structure more compact and thinner. By setting a composite film structure between the first prism and the second prism, a gradient refractive index is deposited while ensuring the connection between the first prism and the second prism, thereby optimizing the optical performance, effectively improving the overall performance of the optical system, enhancing the amount of light entering and the image quality details, and meeting consumers' demand for high-quality imaging. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0016] Figure 1 This is an exploded view of the periscope telephoto camera module of this utility model;

[0017] Figure 2 This is a schematic diagram of the prism assembly of this utility model;

[0018] Figure 3 for Figure 2 An enlarged view of part A shown;

[0019] Figure 4 This is a front view of the prism assembly of this utility model;

[0020] Figure 5 for Figure 4 An enlarged view of part B shown;

[0021] Figure 6 This is a cross-sectional view of the lens assembly of this utility model.

[0022] The meanings of the labels in the attached diagram are as follows:

[0023] 1. Support bracket, 11. Main body, 12. Extension, 121. Outer side, 13. Mating surface, 14. First mounting groove, 15. Second mounting groove, 16. Light inlet, 2. Prism assembly, 2. First prism, 2a. Second prism, 2b. First incident surface, 21. First exit surface, 22. Composite film structure, 23. High refractive index layer, 231. Medium refractive index layer, 232. Low refractive index layer, 233. First reflecting surface, 24. Second exit surface, 25. Second incident surface, 26. Second reflecting surface, 27. Third reflecting surface, 28. Fourth reflecting surface, 29. Image stabilization motor, 3. Lens, 4. Lens assembly, 5. Lens carrier, 51. Protective glass sheet, 52. Light emitting lens, 53. Cover, 54. Light emitting aperture, 541. Image processing assembly, 6. Image sensor, 61. Filter, 62. Circuit board, 63. Connector, 64. Detailed Implementation

[0024] The present invention will be further described below with reference to the accompanying drawings.

[0025] Please see Figures 1 to 6 The periscope telephoto camera module of this utility model includes a bracket 1, a prism assembly 2 mounted on the bracket 1 and having a first incident surface 21 and a first exit surface 22, a lens assembly mounted on the bracket 1 and facing the first incident surface 21, a lens assembly 5 mounted on the bracket 1 and facing the prism assembly 2, and an image processing assembly 6 mounted on the side of the lens assembly 5 facing away from the prism assembly 2. The prism assembly 2 extends the focal length in a composite manner while keeping the height constant, avoiding the periscope telephoto camera module from being too tall and increasing the thickness of the mobile phone, ensuring the compactness and thinness of the entire structure, and meeting the requirements of thinness and lightness. The lens assembly includes a stabilization motor 3 mounted on the bracket and facing the first incident surface 21, and a lens 4 mounted on the stabilization motor 3 and enabling external light sources to be directed toward the first incident surface 21. The image stabilization motor 3 drives the lens 4 to complete autofocus through displacement compensation; the lens 4 is used to focus external light and optimize the beam angle of external light incidence; the lens assembly 5 is used to supplement the optical power of light and ensure light transmittance; the image processing assembly 6 is used to convert light signals into electrical signals to complete image formation.

[0026] In this embodiment, the bracket 1 includes a main body 11 and an extension 12 formed on the main body. The main body has a rectangular parallelepiped structure and a mating surface 13. The direction with the largest dimension of the mating surface 13 is defined as the height direction, the direction corresponding to the width of the main body is defined as the width direction, and the direction corresponding to the length of the main body is defined as the length direction. A horizontal mating surface 13 is provided on one side of the main body along the width. A first mounting groove 14 adapted to the prism assembly 2 is recessed on the mating surface 13. The first mounting groove 14 passes through the mating surface 13 and is open. The prism assembly 2 is installed in the first mounting groove 14 from the open side. The extension 12 is formed on the mating surface 13 and protrudes in the width direction. The extension 12 is located on the mating surface 13 along the height direction close to one of the long sides, so that the other side of the mating surface 13 remains flat. The overall shape of the extension 12 is also adapted to the prism. A second mounting groove 15 adapted to the prism assembly 2 is recessed on the extension 12 along the optical axis direction. The optical axis direction of the incident light is parallel to the height direction. The second mounting groove 15 extends inward through the extension 12 along the optical axis direction and connects to the first mounting groove 14 along the width direction towards the mating surface 13, so that the first mounting groove 14 connects to the second mounting groove 15. The second mounting groove 15 extends along the optical axis direction through an outer side 121 of the extension 12 facing away from the first mounting groove 14 to form a light inlet 16. The image stabilization motor 3 is mounted on the outer side 121 of the extension 12 with the light inlet 16. The outer side 121 is flush with a side of the main body located on the same side along the height direction. The image stabilization motor 3 is larger than the light inlet 16 in order to ensure the installation of the lens 4. Therefore, the image stabilization motor 3 is mounted on the outer side 121 of the extension 12 and the outer wall of the main body that is flush with it, so that the image stabilization motor 3 is mounted on the side of the bracket 1 with the light inlet 16. An installation space is formed between the extension 12 and the mating surface 13. The lens assembly 5 and the image processing assembly 6 are both installed in the installation space. The lens assembly 5 can be glued to the mating surface 13 to make the entire camera module structure compact and reduce its size.

[0027] In this embodiment, the prism assembly 2 includes a first prism 2a mounted on the bracket 1 and having a first incident surface 21, and a second prism 2b mounted on the first prism 2a and having a first exit surface 22. A second mounting groove 15 is adapted to the first prism 2a so that the first prism 2a is mounted within the second mounting groove 15, and a first mounting groove 14 is adapted to the second prism 2b so that the second prism 2b is mounted within the first mounting groove 14. By configuring the prism assembly 2 as a first prism 2a and a second prism 2b, the cooperation of the first prism 2a and the second prism 2b can effectively extend the optical path and thus extend the focal length, achieving high-magnification optical zoom. To ensure the connection between the first prism 2a and the second prism 2b, a composite film structure 23 is provided between the first prism 2a and the second prism 2b to stack and connect them, thereby extending the focal length. While ensuring the extension of the optical path, the composite film structure 23 enables the integrated design of the optical coupler, allowing the first prism 2a and the second prism 2b to be stacked and combined, thus maintaining the overall height of the prism assembly 2 and optimizing the arrangement of the prism assembly 2. At the same time, the composite film structure 23 can be combined with the prism assembly 2 to deposit gradient refractive index anti-reflection, thereby optimizing the overall optical performance, enhancing the amount of light entering and image detail, and meeting consumers' demand for high-quality imaging.

[0028] In this embodiment, the first prism 2a also has a first reflecting surface 24 and a second exiting surface 25. Light enters the first prism 2a from the first incident surface 21 and is sequentially directed towards the first reflecting surface 24 and the second exiting surface 25. Both sides of the first prism 2a along its longitudinal direction are coated with a light-absorbing material. This coating is formed by applying ink in a screen-printed direction followed by an AR film to absorb light, preventing the reflection of ineffective light and avoiding stray light. This also prevents the backlight surface (the part that does not need to reflect light) of the prism assembly 2 from reflecting light outwards, thus avoiding bright spots. In use, light enters the first prism 2a from the first incident surface 21, then passes through the first reflecting surface 24 and is reflected to the second exiting surface 25 before exiting from the second prism 2b, thus changing the direction of the light and facilitating the structural arrangement of the entire camera module. The first prism 2a can be a triangular prism, trapezoidal prism, or other structures, and its configuration depends on actual usage needs and the structural arrangement of each component. Therefore, the first prism 2a has at least a first reflecting surface 24. In this embodiment, the first prism 2a is configured as a triangular prism, with the first incident surface 21, the first reflecting surface 24, and the first exiting surface 22 distributed sequentially. The cross-section of the first prism 2a is preferably an isosceles triangle. Correspondingly, the angle between the first incident surface 21 and the first reflecting surface 24 is 30 degrees, and the angle between the first incident surface 21 and the second exiting surface 25 can be 90 degrees to reduce light scattering. While ensuring that the area of ​​the first incident surface 21 remains unchanged, the refractive index of the first reflecting surface 24 is increased, while the overall height of the first prism 2a is shortened. Corresponding to the triangular prism, the extension 12 and the second mounting groove 15 also have a triangular prism structure to fit the triangular prism. The second mounting groove 15 is connected to the first mounting groove 14 on the right-angled side corresponding to the width direction, and the second mounting groove 15 is connected to the inward side corresponding to the inclined side in the height direction, so that the first prism 2a can be installed in the second mounting groove 15 in the width direction or the height direction.

[0029] The second prism 2b also has a second incident surface 26 and a second reflecting surface 27. Light exits from the second exit surface 25, passes through the composite film structure 23, and then enters the second prism 2b from the second incident surface 26, then enters the second reflecting surface 27 and exits from the first exit surface 22 before reaching the lens assembly 5 and the image processing assembly 6. The two sides of the second prism 2b along its length and the side away from the second incident surface 26 along its width are coated with a light-absorbing material, the same as that of the first prism 2a, which will not be described in detail here. The second prism 2b can be a triangular prism, a trapezoidal prism, or an irregularly shaped prism composed of several triangular or trapezoidal prisms, as needed. Therefore, the second prism 2b has at least a second reflecting surface 27. Light passes through the second incident surface 26 and the second reflecting surface 27 before reaching the first exit surface 22. In this embodiment, the second prism 2b is configured as a trapezoidal prism, and the cross-section of the second prism 2b is an isosceles trapezoid. The second incident surface 26 and the first exit surface 22 are located on the same side. The second prism 2b also includes a third reflecting surface 28 located on the same side as the second incident surface 26 and the first exit surface 22, and a fourth reflecting surface 29 symmetrically distributed with respect to the second reflecting surface 27. The third reflecting surface 28 is located between the second incident surface 26 and the first exit surface 22. The second reflecting surface 27 and the fourth reflecting surface 29 are symmetrically arranged along the height direction on opposite sides of the two waists of the trapezoidal prism. In use, light passes sequentially through the first incident surface 21, the first reflecting surface 24, the second exit surface 25, the composite film structure 23, the second incident surface 26, the second reflecting surface 27, the third reflecting surface 28, and the fourth reflecting surface 29 before reaching the first exit surface 22. The first incident surface 21 is coaxially arranged with the lens 4. The angle between the second incident surface 26 and the second reflecting surface 27 is 45° to ensure total internal reflection when light travels from the second incident surface 26 to the second reflecting surface 27, thus ensuring reflectivity.

[0030] The third reflecting surface 28 and the first exiting surface 22 are jointly configured as a mounting surface. The lens assembly 5 is connected to the mating surface 13 located on the periphery of the first mounting cavity and is also mounted on the mounting surface, so that light emitted from the first exiting surface 22 is directed towards the lens assembly 5. The image processing component 6 is connected to the lens assembly 5, which is equivalent to being mounted on the mounting surface. Both the lens assembly 5 and the image processing component 6 are located within the mounting space, and the lens assembly 5 abuts against the first prism 2a, making the structure of the entire device more compact, thereby optimizing the structural layout between the prism assembly 2 and the lens assembly 5 and reducing costs to a certain extent.

[0031] The composite film structure 23 is formed between the second exit surface 25 and the second incident surface 26 by a coating bonding method. Light, after being incident on the second exit surface 25, sequentially strikes the composite film structure 23, the second reflecting surface 27, and the first exit surface 22 before striking the lens assembly 5 and the image processing assembly 6. This allows the entire prism assembly 2 to balance spatial compression and optical path control. The composite film lens 4 structure sequentially includes a high refractive index layer 231 with a refractive index of nd1, a medium refractive index layer 232 with a refractive index of nd2, and a low refractive index layer 233 with a refractive index of nd3, where nd1 > nd2 > nd3. The high refractive index layer 231 is bonded to the second exit surface 25, and the low refractive index layer 233 is bonded to the second incident surface 26. This forms a deposited gradient refractive index antireflective coating between the first prism 2a and the second prism 2b. The three-layer film structure optimizes optical performance, effectively improving the overall performance of the optical system, enhancing light intake and image detail, and meeting consumers' demands for high-quality imaging. By employing a multi-layered structure with decreasing refractive index, reflectivity is increased, resulting in a more precise reflection ratio. Simultaneously, the gradient refractive index coating structure buffers interlayer stress caused by temperature changes, preventing cracking or deformation of the bonded surface. Positioning the low-refractive-index layer 233 close to the second incident surface 26 reduces interface reflection loss and improves overall transmittance. Furthermore, the low-refractive-index transition of the low-refractive-index layer 233 balances dispersion effects, enhancing image clarity. The thicknesses of the high-refractive-index layer 231, the medium-refractive-index layer 232, and the low-refractive-index layer 233 are t1, t2, and t3, respectively, where t1 + t2 + t3 = λ / 4, and λ is the wavelength of the incident light. Through constructive interference, the film thicknesses of the high-refractive-index layer 231, the medium-refractive-index layer 232, and the low-refractive-index layer 233 are t = λ / 4n, i.e., the optical thickness nt = λ / 4. The optical path difference of light traveling back and forth in the thin film is λ / 2, satisfying the constructive interference condition. Therefore, t1 + t2 + t3 = λ / 4 is required, while ensuring the anti-reflection effect. At the same time, since the high-refractive-index layer 231 has a high refractive index and the low-refractive-index layer 233 has a low refractive index, in order to meet optical requirements, the thickness of the high-refractive-index layer 231 can be smaller than that of the low-refractive-index layer 233. The high-refractive-index layer 231 is sensitive to short wavelengths, while the low-refractive-index layer 233 is sensitive to long wavelengths. By combining these layers, the anti-reflection band range can be broadened, and the dispersion effect can be reduced. Meanwhile, by matching the thickness with the refractive index, the thermal deformation amplitude can be reduced under the influence of the coefficient of thermal expansion when the temperature changes, ensuring thermal stability and achieving thermal stress matching. The gradient thickness distribution can provide a buffer. Thickness gradient combinations can specifically suppress reflections at specific wavelengths (such as 532nm stray light in laser systems), reduce ghosting and glare in optical systems, and achieve the purpose of suppressing stray light.

[0032] In another embodiment, t1 = t2 = t3, for example: t1 = t2 = t3 = 45nm. Correspondingly, the refractive indices can be nd1 = 1.85, nd2 = 1.65, and nd3 = 1.38, respectively. The high refractive index layer 231 can be zinc sulfide (ZnS), the medium refractive index layer 232 can be titanium dioxide (TiO2), and the low refractive index layer 233 can be magnesium fluoride (MgF2). The wavelength of the incident light is λ = 550nm, i.e., green light, and the refractive indices decrease in the order: 1.85 > 1.65 > 1.38. The total thickness is: t1 + t2 + t3 = 135nm ≈ λ / 4 (550 / 4 = 137.5nm). By ensuring that the proportion of each film layer remains consistent and optimizing the destructive interference conditions, the phase delay of the light beam on both sides of the interface is ensured to be consistent, avoiding symmetrical wavefront distortion introduced by thickness differences. Simultaneously, the fabrication complexity of multilayer films can be reduced, and the uniformity and yield of the film layers can be improved.

[0033] In this embodiment, the image stabilization motor 3 uses an existing voice coil motor and can be driven by a miniature linear motor. A closed-loop control of a position sensor is set in the image stabilization motor 3. When the lens 4 is mounted on the image stabilization motor 3, the prism spacing can be precisely adjusted and real-time feedback can be achieved, which facilitates motor drive. Combined with the automatic optimization function of the image analysis algorithm, the accuracy and stability of the lens 4 are greatly improved, ensuring high-quality imaging under different optical zoom conditions.

[0034] In this embodiment, the lens 4 is mounted on the image stabilization motor 3 and constrained thereon by a carrier. Image stabilization of the lens 4 is achieved through electromagnetic force via a magnet mounted on the carrier and a coil on the image stabilization motor 3. The lens 4 contains lenses, which can be two or more, such as four, arranged sequentially along the optical axis. In one embodiment, the two lenses closest to the object side have positive optical power, and the two lenses closest to the prism assembly 2 have negative optical power. The side of the two lenses with positive optical power facing the object side can be convex to ensure that light entering from the object side is focused, while the two lenses with negative optical power reduce the degree of light deflection, resulting in a smoother light transition. The lens 4 is prior art and can be referenced to any type of lens 4 used in a camera module, especially a lens 4 for a periscope camera module, which will not be described in detail here.

[0035] In this embodiment, the lens assembly 5 includes a lens carrier 51 mounted on the mating surface 13 of the bracket 1, a protective glass sheet 52 mounted inside the lens carrier 51, a light-emitting lens 53 mounted inside the lens carrier 51, and an anti-fog coating coated on the protective glass sheet 52. The anti-fog coating is close to the first emission surface 22, and the light-emitting lens 53 is located on the side away from the first emission surface 22. To avoid affecting the prism assembly 2, the lens carrier 51 is suspended above the first emission surface 22 and spaced apart from it. The inner wall of the lens carrier 51 has mounting grooves for mounting the protective glass sheet 52 and the light-emitting lens 53. A cover 54 can be placed on the lens carrier 51 to further restrict the protective glass sheet 52 and the light-emitting lens 53. A light-emitting hole 541 is formed in the cover 54, and the image processing assembly 6 is mounted on the cover 54 and arranged directly opposite the light-emitting hole 541. The protective glass sheet 52 protects the light-emitting lens 53, and an anti-fog coating is applied to the protective glass sheet 52 to prevent fogging and ensure imaging quality. The light-emitting lens 53 is a convex lens. After light exits from the first exiting surface 22, it passes through the light-emitting lens 53, which can refocus the diverging light onto the image processing component 6, ensuring precise focusing of the light, supplementing the optical power of the optical system, and ensuring image clarity. In another embodiment, the protective glass sheet 52 is fixedly sealed at the light-emitting hole 541 to block external moisture and ensure that the inside of the lens remains as dry as possible. In yet another embodiment, protective glass sheets 52 can be provided on both sides of the cover 54 along the light-emitting optical axis. The protective glass sheets 52 should be made of high-transmittance glass, such as ultra-clear glass.

[0036] In this embodiment, the image processing component 6 includes an image sensor 61, a filter 62, a circuit board 63, and a connector 64. The filter 62 and the image sensor 61 are sequentially mounted on the cover 54 of the lens carrier 51 and cover the light outlet. The filter 62 faces the lens assembly 5 and the first emission surface 22 to filter out unwanted light. After passing through the filter 62, the light is directed to the image sensor 61. The image sensor 61 and the connector 64 are both electrically connected to the circuit board 63, which is fixed to the lens carrier 51. The image sensor 61 converts the light signal into an electrical signal for the formation of an image.

[0037] It should be noted that a temperature sensor can be installed on the bracket 1 and electrically connected to the circuit board 63 to detect the ambient temperature around the entire camera module and feed it back to the image processing component 6.

[0038] The working method of one embodiment of the periscope telephoto camera module of this utility model is as follows: external light is directed towards the lens 4, and the image stabilization motor 3 automatically focuses the lens 4, so that the light passes through the lens 4 and is directed towards the first incident surface 21 and then into the first prism 2a. After entering the first prism 2a, the light is directed towards the first reflecting surface 24 and then out of the second exit surface 25. After passing through the composite film structure 23 for anti-reflection and optical performance enhancement, the light is directed towards the second incident surface 26 and then into the second prism 2b. After entering the second prism 2b, the light is directed towards the second reflecting surface 27, the third reflecting surface 28 and the fourth reflecting surface 29 in sequence and then out of the first exit surface 22 to extend the focal length. After that, the light is focused by the light-emitting lens 53 and then filtered by the filter 62 to remove invalid light, so that the effective light (the light that the image sensor 61 can receive) is directed towards the image sensor 61 for photoelectric conversion, converting the light signal into an electrical signal for processing.

[0039] Compared with existing technologies, the periscope telephoto camera module of this invention, after light is incident from the lens 4 onto the first incident surface 21, passes sequentially through the first reflecting surface 24, the second exiting surface 25, the composite film structure 23, the second incident surface 26, the second reflecting surface 27, the third reflecting surface 28, and the fourth reflecting surface 29 before exiting from the first exiting surface 22, thus achieving the telephoto function. Through the cooperation of the surface coatings of the first prism 2a and the second prism 2b and the composite film structure 23, the reflection of ineffective light is reduced, and the interference of stray light is decreased, thereby improving image quality, reducing light energy loss caused by reflection, and enhancing the surface wear resistance of the prism assembly 2, preventing scratches and damage. This reduces wear on the prism surface, extending its lifespan. Simultaneously, it improves light transmittance, allowing more light to pass smoothly through the prism assembly 2, reducing surface wear caused by light scattering. Furthermore, the coating reduces glare, enhancing visual comfort and further reducing glare-induced prism surface wear, thus minimizing the need for external protective measures and lowering manufacturing costs and usage risks. The combination of the prism assembly 2 and lens assembly 5 achieves optical processing at the material interface. Through the cooperation of the image stabilization motor 3 and a combination of mechanical and optical path adjustment, it overcomes the design limitations of traditional camera modules, achieving an organic combination of telephoto and high-quality imaging.

Claims

1. A periscope telephoto camera module, comprising a bracket, a prism assembly mounted on the bracket and having a first incident surface and a first exit surface, a lens assembly mounted on the bracket and facing the first incident surface, and an image processing assembly; characterized in that: The prism assembly includes a first prism mounted on a bracket and having a first incident surface, and a second prism mounted on the first prism and having a first exit surface. A composite film structure is provided between the first prism and the second prism to stack and connect the first prism and the second prism and extend the focal length.

2. The periscope telephoto camera module as described in claim 1, characterized in that: The composite film structure comprises, in sequence, a high refractive index layer with a refractive index of nd1, a medium refractive index layer with a refractive index of nd2, and a low refractive index layer with a refractive index of nd3, where nd1 > nd2 > nd3. The high refractive index layer is attached to the second exit surface, and the low refractive index layer is attached to the second incident surface.

3. The periscope telephoto camera module as described in claim 2, characterized in that: The thicknesses of the high refractive index layer, the medium refractive index layer, and the low refractive index layer are t1, t2, and t3, respectively, where t1 + t2 + t3 = λ / 4, and λ is the wavelength of the incident light.

4. The periscope telephoto camera module as described in any one of claims 1 to 3, characterized in that: The first prism also has a first reflecting surface and a second exiting surface. After entering the first prism from the first incident surface, light is sequentially directed toward the first reflecting surface and the second exiting surface. The second prism also has a second incident surface and a second reflecting surface. A composite film structure is formed between the second exiting surface and the second incident surface. After being directed toward the second exiting surface, light is sequentially directed toward the composite film structure, the second reflecting surface, and the first exiting surface before being directed toward the image processing component.

5. The periscope telephoto camera module as described in claim 4, characterized in that: The first prism is configured as a triangular prism, with a first incident surface, a first reflecting surface, and a first exiting surface distributed sequentially; the second prism is configured as a trapezoidal prism, with the second incident surface and the first exiting surface located on the same side, and the second prism also includes a third reflecting surface on the same side as the second incident surface and a fourth reflecting surface symmetrically distributed with the second reflecting surface. Light passes sequentially through the first incident surface, the first reflecting surface, the second exiting surface, the composite film structure, the second incident surface, the second reflecting surface, the third reflecting surface, and the fourth reflecting surface before being directed toward the first exiting surface. The first incident surface is coaxial with the lens.

6. The periscope telephoto camera module as described in claim 5, characterized in that: The angle between the first incident surface and the first reflecting surface is 30°, and the angle between the second incident surface and the second reflecting surface is 45°.

7. The periscope telephoto camera module as described in claim 5, characterized in that: The third reflecting surface and the first exiting surface are configured together as a mounting surface, and the image processing component is mounted on the mounting surface and abuts against the first prism.

8. The periscope telephoto camera module as described in claim 7, characterized in that: A lens assembly is mounted on the mounting surface, and the image processing assembly is mounted on the side of the lens assembly facing away from the mounting surface.

9. The periscope telephoto camera module as described in claim 8, characterized in that: The lens assembly includes a protective glass sheet, a light-emitting lens, and an anti-fog coating applied to the protective glass sheet. The anti-fog coating is close to the first emission surface, and the light-emitting lens is located on the side away from the first emission surface.

10. The periscope telephoto camera module as described in claim 1, characterized in that: The bracket has a mating surface, on which a first mounting groove adapted to the second prism is recessed, and the second prism is installed in the first mounting groove; an extension is formed on the side of the mating surface corresponding to the second incident surface, and a second mounting groove adapted to the first prism and connected to the first mounting groove is recessed along the optical axis direction on the extension, and the first prism is installed in the second mounting groove; the second mounting groove passes through the side of the extension facing away from the first mounting groove along the optical axis direction to form a light inlet, and the lens assembly is installed on the side of the bracket with the light inlet and arranged directly opposite the first incident surface to the light inlet.

Images