Long-focus camera module

Abstract

The invention relates to the field of optical imaging, and discloses a 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, an anti-shake motor arranged on the bracket, a lens arranged on the anti-shake motor, and an image processing assembly, the prism assembly comprises a first prism installed on the support and provided with a first incident plane 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] The present invention relates to the field of optical imaging, and in particular to a telephoto camera module. Background Art

[0002] With the prevalence of smart electronic devices, people's dependence on mobile phones in daily life continues to increase, especially in terms of communication and camera functions. To meet consumers' demand for mobile phone camera performance, the demand for telephoto lenses in mobile phones is increasing. Traditional optical zoom technology achieves zoom by moving lens components, but 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 lens components, resulting in poor shooting results and failing to meet consumers' demand for high magnification. To overcome these limitations, periscope lenses have emerged. By incorporating prisms into the lens imaging system, periscope lenses can extend the focal length without increasing the thickness of the phone, supporting larger sensors, thereby enhancing light intake and image quality. However, existing periscope lenses still have some problems. Existing periscope lens modules have not fully optimized the height and width of the lens module while maintaining performance indicators, which affects the compactness of the overall design. Traditional glass total internal reflection prisms are easily damaged and require additional protection, increasing manufacturing costs and user risks. Summary of the Invention

[0003] In view of the above-mentioned deficiencies in the prior art, the technical problem to be solved by the present invention is: to provide a telephoto camera module to solve the problem that it is difficult to achieve high-magnification optical zoom without increasing the thickness of the mobile phone, resulting in poor imaging quality and appearance.

[0004] In order to solve the above technical problems, a technical solution adopted by the present invention is: providing a telephoto camera module including a bracket, a prism assembly installed on the bracket and having a first incident surface and a first exit surface, an anti-shake motor installed on the bracket and facing the first incident surface, a lens installed on the anti-shake motor and allowing an external light source to be directed toward the first incident surface, and an image processing component; the prism assembly includes a first prism installed on the bracket and having a first incident surface and a second prism installed on the first prism and having a first exit surface, and a composite film system structure is provided between the first prism and the second prism to enable the first prism and the second prism to be stacked and connected and to extend the focal length.

[0005] Furthermore, the composite film structure 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, nd1>nd2>nd3, the high refractive index layer is adhered to the second exit surface, and the low refractive index layer is adhered 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, and t1+t2+t3=λ / 4, where λ is the wavelength of the incident light.

[0007] Furthermore, the first prism also has a first reflection surface and a second exit surface. After the light enters the first prism from the first incident surface, it is sequentially emitted toward the first reflection surface and the second exit surface. The second prism also has a second incident surface and a second reflection surface. The composite film structure is formed between the second exit surface and the second incident surface. After the light is emitted toward the second exit surface, it is sequentially emitted toward the composite film structure, the second reflection surface, and the first exit surface, and then toward the image processing component.

[0008] Furthermore, the first prism is configured as a triangular prism, and the first incident surface, the first reflection surface and the first exit surface are distributed in sequence; the second prism is configured as a trapezoidal prism, and the second incident surface and the first exit surface are located on the same side, and the second prism also includes a third reflection surface on the same side as the second incident surface and a fourth reflection surface symmetrically distributed with respect to the second reflection surface. The light passes through the first incident surface, the first reflection surface, the second exit surface, the composite film structure, the second incident surface, the second reflection surface, the third reflection surface, and the fourth reflection surface in sequence and then is emitted toward the first exit surface. The first incident surface is coaxial with the lens arrangement.

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

[0010] Furthermore, the third reflection surface and the first emission surface are jointly configured 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 a 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 exit surface, and the light-emitting lens is located on a side away from the first exit 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 mounted in the first mounting groove; an extension portion is extended 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 on the extension portion along the optical axis direction, and the first prism is mounted in the second mounting groove; the second mounting groove passes through a side of the extension portion facing away from the first mounting groove along the optical axis direction to form a light inlet, the anti-shake motor is mounted on a side surface of the bracket having the light inlet, and the lens and the first incident surface are arranged opposite the light inlet.

[0014] The telephoto camera module of the present invention has at least the following beneficial effects: through the composite setting of 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 thin; by arranging a composite film structure between the first prism and the second prism, while ensuring the connection between the first prism and the second prism, a gradient refractive index is deposited to achieve optimization of optical performance, effectively improve the overall performance of the optical system, enhance the amount of light entering and image quality details, and meet consumers' demand for high-quality imaging. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0016] Figure 1 This is an exploded view of the telephoto camera module of the present invention;

[0017] Figure 2 is a schematic structural diagram of the prism assembly of the present invention;

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

[0019] Figure 4 is a front view of a prism assembly of the present invention;

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

[0021] Figure 6 It is a cross-sectional view of the lens assembly of the present invention.

[0022] The meanings of the reference numerals in the accompanying drawings are:

[0023] Bracket 1, main body 11, extension part 12, outer side surface 121, mating surface 13, first mounting groove 14, second mounting groove 15, light inlet 16, 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 reflection surface 24, second exit surface 25, second incident surface 26, second reflection surface 27, third reflection surface 28, fourth reflection surface 29, anti-shake motor 3, lens 4, lens assembly 5, lens carrier 51, protective glass sheet 52, light output lens 53, cover body 54, light output hole 541, image processing component 6, image sensor 61, filter 62, circuit board 63, connector 64. DETAILED DESCRIPTION

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

[0025] See also Figures 1 to 6 The telephoto camera module of the present invention 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, an anti-shake motor 3 mounted on the bracket 1 and facing the first incident surface 21, a lens 4 mounted on the anti-shake motor 3 and enabling an external light source to be directed toward 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, wherein the prism assembly 2 extends the focal length in a composite manner and keeps the height unchanged, thereby avoiding the entire telephoto camera module being too high and increasing the thickness of the mobile phone, ensuring the compactness and lightness of the entire structure, and meeting the requirements of lightness and thinness; the anti-shake motor 3 drives the lens 4 to complete automatic focus through displacement compensation; the lens 4 is used to focus external light and optimize the beam angle of the external light; the lens assembly 5 is used to supplement the optical power of the light and ensure the transmittance; the image processing assembly 6 is used to complete the formation of the image after converting the optical signal into an electrical signal.

[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 an overall rectangular parallelepiped structure and has a mating surface 13. The direction of 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 of 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 is recessed in the mating surface 13 to accommodate the prism assembly 2. The first mounting groove 14 extends through the mating surface 13 and is open. The prism assembly 2 is mounted therein from the open side of the first mounting groove 14. 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 on the side of 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 similarly compatible with the prism. A second mounting groove 15 is recessed along the optical axis of the extension 12, which mates with the prism assembly 2. The optical axis of the incident light is aligned parallel to the height. The second mounting groove 15 extends inward through the extension 12 along the optical axis and connects to the first mounting groove 14 along the width direction, toward the mating surface 13, connecting the first mounting groove 14 to the second mounting groove 15. The second mounting groove 15 extends along the optical axis through an outer side surface 121 of the extension 12 facing away from the first mounting groove 14, forming a light inlet 16. The anti-shake motor 3 is mounted on the outer side surface 121 of the extension 12, which has the light inlet 16. This outer side surface 121 is flush with the side surface of the main body that is on the same side along the height direction. To ensure proper mounting of the lens 4, the anti-shake motor 3 is larger than the light inlet 16. Therefore, the anti-shake motor 3 is mounted on the outer side surface 121 of the extension 12 and the outer wall of the main body that is flush with it, so that the anti-shake motor 3 is mounted on the side of the bracket 1 that has the light inlet 16. An installation space is formed between the extension portion 12 and the mating surface 13, and the lens assembly 5 and the image processing assembly 6 are both installed in the installation space. The lens assembly 5 can be adhered to the mating surface 13 by using glue to make the entire camera module structure compact and reduce the volume.

[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. The second mounting groove 15 is adapted to fit the first prism 2a so that the first prism 2a is mounted within the second mounting groove 15, and the first mounting groove 14 is adapted to fit the second prism 2b so that the second prism 2b is mounted within the first mounting groove 14. By configuring the prism assembly 2 to include the first prism 2a and the second prism 2b, the cooperation of the first prism 2a and the second prism 2b can effectively extend the optical path and thus the focal length, thereby achieving high-power optical zoom. In order 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, which enables the first prism 2a and the second prism 2b to be stacked and connected and extends the focal length. While ensuring the extension of the optical path, the setting of the composite film structure 23 realizes the integrated design of the optical coupling body, so that the first prism 2a and the second prism 2b are stacked and composited, thereby maintaining the overall height of the prism assembly 2 unchanged to optimize the layout of the prism assembly 2; at the same time, the composite film structure 23 can be combined with the prism assembly 2 to deposit a gradient refractive index to enhance transmittance, thereby achieving overall optimization of the optical performance, enhancing the amount of light entering and the details of the image quality, and meeting consumers' demand for high-quality imaging.

[0028] In the content defined in this embodiment, the first prism 2a also has a first reflecting surface 24 and a second emitting surface 25. After the light enters the first prism 2a from the first incident surface 21, it is sequentially emitted toward the first reflecting surface 24 and the second emitting surface 25. Among them, the first prism 2a is coated with a light-absorbing material on both sides along the long direction. It can be coated with ink in the silk-screen direction and then coated with an AR film to form a coating for light absorption, thereby avoiding the reflection of invalid light to form stray light, and preventing the backlight surface of the prism assembly 2 (the part that does not need to reflect light) from reflecting light to the outside, thereby avoiding the formation of bright spots. When in use, light enters the first prism 2a from the first incident surface 21, and then passes through the first reflecting surface 24 and is reflected to the second emitting surface 25 before being emitted from the second prism 2b to change the direction of the light, thereby facilitating the structural arrangement inside the entire camera module. The first prism 2a can be a triangular prism, a trapezoidal prism, or other structures, which are arranged according to actual use needs and the structural arrangement of each component. Therefore, the first prism 2a has at least a first reflective surface 24. In this embodiment, the first prism 2a is configured as a triangular prism, and the first incident surface 21, the first reflective surface 24, and the first exit surface 22 are distributed in sequence. 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 reflective surface 24 is 30 degrees, and the angle between the first incident surface 21 and the second exit surface 25 can be 90 degrees, so as to reduce the scattering of light, increase the refractive index of the first reflective surface 24 while ensuring that the area of ​​the first incident surface 21 remains unchanged, and shorten the overall height of the first prism 2a. Corresponding to the triangular prism, the extension portion 12 and the second mounting groove 15 also have a triangular prism-shaped structure and are adapted to the triangular prism. The second mounting groove 15 is connected to the first mounting groove 14 on the right-angle surface corresponding to the width direction, and the second mounting groove 15 is passed inward along the height direction corresponding to the inclined surface, so that the first prism 2a can be installed in the second mounting groove 15 along the width direction or the height direction.

[0029] The second prism 2b also has a second incident surface 26 and a second reflective surface 27. Light is emitted from the second exit surface 25 and passes through the composite film structure 23. After emitting from the second incident surface 26, it is emitted into the second prism 2b, and then emitted to the second reflective surface 27. After emitting from the first exit surface 22, it is emitted to the lens assembly 5 and the image processing assembly 6. Among them, the two side surfaces of the second prism 2b along the longitudinal direction and the side away from the second incident surface 26 along the width direction are coated with a light-absorbing material. The light-absorbing material is the same as the light-absorbing material of the first prism 2a and will not be described in detail here. The second prism 2b can be a triangular prism, a trapezoidal prism, or a special-shaped prism composed of several triangular prisms or trapezoidal prisms as needed. Therefore, the second prism 2b has at least a second reflective surface 27. After passing through the second incident surface 26 and the second reflective surface 27, the light is emitted to 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, and the second prism 2b also includes a third reflective surface 28 located on the same side as the second incident surface 26 and the first exit surface 22, and a fourth reflective surface 29 symmetrically distributed with respect to the second reflective surface 27. The third reflective surface 28 is located between the second incident surface 26 and the first exit surface 22, and the second reflective surface 27 and the fourth reflective surface 29 are symmetrically arranged on opposite sides of the two waists of the trapezoidal prism along the height direction. During use, light passes through the first incident surface 21, the first reflective surface 24, the second exit surface 25, the composite film structure 23, the second incident surface 26, the second reflective surface 27, the third reflective surface 28, and the fourth reflective surface 29 in sequence before being emitted to the first exit surface 22. The first incident surface 21 is arranged coaxially with the lens 4. The angle between the second incident surface 26 and the second reflective surface 27 is 45° to ensure total internal reflection of light from the second incident surface 26 to the second reflective surface 27, thereby ensuring a high reflectivity.

[0030] The third reflective surface 28 and the first exit surface 22 are collectively configured as a mounting surface. The lens assembly 5 is connected to the mating surface 13 located outside the first mounting cavity and is also mounted on the mounting surface, so that light emitted from the first exit surface 22 is directed toward the lens assembly 5. The image processing assembly 6 is connected to the lens assembly 5, which is equivalent to being mounted on the mounting surface. The lens assembly 5 and the image processing assembly 6 are both located within the mounting space, and the lens assembly 5 is supported on 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 coating and gluing. After the light is emitted to the second exit surface 25, it is emitted to the composite film structure 23, the second reflection surface 27, and the first exit surface 22 in sequence, and then to the lens assembly 5 and the image processing assembly 6, so that the entire prism assembly 2 can take into account both spatial compression and light 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, wherein nd1>nd2>nd3. The high refractive index layer 231 is attached to the second exit surface 25, and the low refractive index layer 233 is attached to the second incident surface 26. Thus, a deposited gradient refractive index anti-reflection film is formed 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 the amount of light entering and the image quality details, and meeting consumers' demand for high-quality imaging. By creating a multi-layered structure with a gradient of refractive index from high to low, reflectivity is increased, resulting in a more precise reflection ratio. Furthermore, the gradient refractive index coating structure can buffer interlayer stress caused by temperature changes, preventing cracking or deformation of the bonded surfaces. Placing the low refractive index layer 233 close to the second incident surface 26 reduces interfacial reflection losses and improves overall transmittance. The low refractive index transition of the low refractive index layer 233 balances the dispersion effect and enhances imaging 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, where λ is the wavelength of the incident light. Through constructive interference, the film thickness of the high refractive index layer 231, the medium refractive index layer 232 and the low refractive index layer 233 is t = λ / 4n, that is, the optical thickness nt = λ / 4, and the optical path difference of light traveling back and forth in the film is λ / 2, which meets the constructive interference condition, so t1+t2+t3=λ / 4 is required, while ensuring the anti-reflection effect. At the same time, since the refractive index of the high refractive index layer 231 is high and the refractive index of the low refractive index layer 233 is low, in order to meet the 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 and the low refractive index layer 233 is sensitive to long wavelengths. The combined arrangement can broaden the anti-reflection band range and reduce the influence of dispersion. At the same time, by adapting the thickness to the refractive index, the thermal deformation amplitude can be reduced when the temperature changes under the influence of the thermal expansion coefficient, thereby ensuring thermal stability and achieving thermal stress matching, and the gradient thickness distribution can provide a buffer. The thickness gradient combination can specifically suppress the reflection of 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 = 45 nm. Corresponding 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). For incident light with a wavelength of λ = 550 nm (green light), the refractive index decreases: 1.85 > 1.65 > 1.38. The total thickness is: t1 + t2 + t3 = 135 nm ≈ λ / 4 (550 / 4 = 137.5 nm). By ensuring the consistency of the proportions of each film layer and optimizing the destructive interference conditions, the phase delay of the light beam on both sides of the interface is consistent, avoiding symmetrical wavefront distortion due to thickness differences. This also reduces the complexity of multilayer film preparation and improves film uniformity and yield.

[0033] In this embodiment, the anti-shake motor 3 uses an existing voice coil motor, and a micro linear motor drive system can be adopted. A closed-loop control of a position sensor is set in the anti-shake motor 3. When the lens 4 is installed on the anti-shake motor 3, precise adjustment and real-time feedback of the prism spacing are achieved, which is convenient for motor driving. 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 states.

[0034] In this embodiment, the lens 4 is mounted on the anti-shake motor 3 and is restricted on the anti-shake motor 3 through a carrier. The anti-shake function of the lens 4 is achieved by installing a magnet on the carrier and a coil on the anti-shake motor 3 through electromagnetic force. A lens is provided in the lens 4. The lenses can be set to more than two, such as four, and arranged in sequence along the optical axis. In one embodiment, the two lenses close to the object side have positive optical focal length, and the two lenses close to the prism assembly 2 have negative optical focal length. The two lenses with positive optical focal length can be convex on the side facing the object side to ensure that the light is focused after entering from the object side, while the two lenses with negative optical focal length slow down the degree of deflection of the light, so that the light transitions smoothly. The lens 4 is a prior art and can refer to any lens 4 for a camera module, especially the 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 within the lens carrier 51, a light-emitting lens 53 mounted within the lens carrier 51, and an anti-fog coating applied to the protective glass sheet 52. The anti-fog coating is located proximal to the first exit surface 22, while the light-emitting lens 53 is located on a side away from the first exit surface 22. To prevent interference with the prism assembly 2, the lens carrier 51 is suspended above the first exit surface 22 and spaced apart from the first exit surface 22. The inner wall of the lens carrier 51 is provided with a mounting groove for mounting the protective glass sheet 52 and the light-emitting lens 53. A cover 54 can be provided over the lens carrier 51 to further restrain the protective glass sheet 52 and the light-emitting lens 53. A light-emitting hole 541 is defined in the cover 54, and the image processing assembly 6 is mounted on the cover 54, facing the light-emitting hole 541. Among them, the protective glass sheet 52 is used to protect the light-emitting lens 53, and an anti-fog coating is applied to the protective glass sheet 52 to prevent fogging and ensure the imaging effect. The light-emitting lens 53 is a convex lens. After the light is emitted from the first exit surface 22 and then passes through the light-emitting lens 53, it can converge the divergent light to the image processing component 6, ensure the precise focusing of the light, supplement the optical power of the optical system, and ensure the clarity of the imaging. In another embodiment, the protective glass sheet 52 is fixedly packaged at the light-emitting hole 541 to block external moisture and ensure that the environment inside the lens is kept as dry as possible. In another embodiment, protective glass sheets 52 can be set on both sides of the cover body 54 along the light-emitting optical axis. The protective glass sheet 52 should be made of high-transmittance glass, such as ultra-white 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, wherein 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 exit surface 22 and is used to filter out unnecessary light, and then the light passes through the filter 62 and is emitted to the image sensor 61. The image sensor 61 and the connector 64 are both electrically connected to the circuit board 63, and the circuit board 63 is fixed on the lens carrier 51. The image sensor 61 converts the optical signal into an electrical signal for the formation of graphics.

[0037] It should be noted that a temperature sensor may be provided 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] One embodiment of the telephoto camera module of the present invention works as follows: external light is directed toward the lens 4, and the anti-shake motor 3 realizes automatic focus of the lens 4, so that the light passes through the lens 4 and is directed toward the first incident surface 21 and then enters the first prism 2a. After entering the first prism 2a, the light is directed toward the first reflection surface 24 and then emitted from the second exit surface 25 and is subjected to anti-reflection and optical performance improvement by the composite film structure 23, and then is directed toward the second incident surface 26 and enters the second prism 2b. After entering the second prism 2b, the light is sequentially directed toward the second reflection surface 27, the third reflection surface 28 and the fourth reflection surface 29 and then is emitted from the first exit surface 22 to extend the focal length. Afterwards, the light is focused by the light-emitting lens 53 and then filtered out by the filter 62 to remove invalid light, so that the effective light (light that can be received by the image sensor 61) is directed to the image sensor 61 for photoelectric conversion, and the optical signal is converted into an electrical signal for processing.

[0039] Compared with the prior art, the telephoto camera module of the present invention realizes the telephoto function by emitting light from the lens 4 to the first incident surface 21, and then passing through the first reflection surface 24, the second exit surface 25, the composite film structure 23, the second incident surface 26, the second reflection surface 27, the third reflection surface 28, and the fourth reflection surface 29 in sequence, and then being set from the first exit surface 22; through the surface coating of the first prism 2a and the second prism 2b and the cooperation of the composite film structure 23, the reflection of invalid light is reduced, the interference of stray light is reduced, thereby improving the imaging quality, reducing the loss of light energy caused by reflection, enhancing the surface wear resistance of the prism assembly 2, and preventing scratches and damage. This reduces the wear on the prism surface and increases its service life. At the same time, it improves light transmittance, allowing more light to pass through the prism assembly 2 smoothly, reducing surface wear caused by light scattering. At the same time, it reduces the impact of glare through coating, improves visual comfort, and reduces the wear on the prism surface caused by glare, thereby reducing the need for external protective measures, reducing manufacturing costs and risks of use. The combination of the prism assembly 2 and the lens assembly 5 realizes optical processing of the material interface, and through the cooperation of the anti-shake motor 3, combined with mechanical optical path adjustment, breaks through the design limitations of traditional camera modules and realizes the organic combination of telephoto and high-quality imaging.

Claims

1. A telephoto camera module comprising a bracket, a prism assembly mounted on the bracket and having a first incident surface and a first exit surface, an anti-shake motor mounted on the bracket and facing the first incident surface, a lens mounted on the anti-shake motor and capable of directing an external light source toward 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 system structure is provided between the first prism and the second prism to connect the first prism and the second prism in a stacked manner and extend the focal length.

2. The telephoto camera module according to claim 1, wherein: The composite film structure 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, nd1>nd2>nd3, the high refractive index layer is adhered to the second exit surface, and the low refractive index layer is adhered to the second incident surface.

3. The telephoto camera module according to claim 2, wherein: 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, t1+t2+t3=λ / 4, where λ is the wavelength of the incident light.

4. The telephoto camera module according to any one of claims 1 to 3, wherein: The first prism also has a first reflection surface and a second exit surface. After the light enters the first prism from the first incident surface, it is sequentially emitted toward the first reflection surface and the second exit surface. The second prism also has a second incident surface and a second reflection surface. A composite film structure is formed between the second exit surface and the second incident surface. After the light is emitted toward the second exit surface, it is sequentially emitted toward the composite film structure, the second reflection surface, and the first exit surface, and then toward the image processing component.

5. The telephoto camera module according to claim 4, wherein: The first prism is configured as a triangular prism, with a first incident surface, a first reflection surface and a first exit surface distributed in sequence; the second prism is configured as a trapezoidal prism, with the second incident surface and the first exit surface located on the same side, and the second prism further comprising a third reflection surface on the same side as the second incident surface and a fourth reflection surface symmetrically distributed with respect to the second reflection surface. Light passes through the first incident surface, the first reflection surface, the second exit surface, the composite film structure, the second incident surface, the second reflection surface, the third reflection surface and the fourth reflection surface in sequence and is emitted toward the first exit surface. The first incident surface is coaxial with the lens arrangement.

6. The telephoto camera module according to claim 5, wherein: The included angle between the first incident surface and the first reflecting surface is 30°, and the included angle between the second incident surface and the second reflecting surface is 45°.

7. The telephoto camera module according to claim 5, wherein: The third reflecting surface and the first emitting surface are jointly configured as a mounting surface, and the image processing component is mounted on the mounting surface and abuts against the first prism.

8. The telephoto camera module according to claim 7, wherein: A lens assembly is mounted on the mounting surface, and the image processing assembly is mounted on a side of the lens assembly facing away from the mounting surface.

9. The telephoto camera module according to claim 8, wherein: 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 exit surface, and the light-emitting lens is located on a side away from the first exit surface.

10. The telephoto camera module according to claim 1, wherein: The bracket has a mating surface, on which a first mounting groove adapted to the second prism is recessed, and the second prism is mounted in the first mounting groove; an extension portion is extended on a 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 on the extension portion along the optical axis direction, and the first prism is mounted in the second mounting groove; the second mounting groove passes through a side of the extension portion facing away from the first mounting groove along the optical axis direction to form a light inlet, the anti-shake motor is mounted on a side surface of the bracket having the light inlet, and the lens and the first incident surface are arranged opposite the light inlet.

Images