Optical imaging system, camera module and electronic equipment

Abstract

The utility model relates to the technical field of optical imaging, and discloses an optical imaging system, a camera module and an electronic device, the optical imaging system comprises a lens assembly, an imaging assembly and a prism assembly, the prism assembly is provided with an incident plane and an emergent plane which are located at the same side, the lens assembly is right opposite to the incident plane, the imaging assembly is right opposite to the emergent plane, and the lens assembly is provided with a lens. A stray light improving area used for improving stray light is formed on the prism assembly, and light is reflected for multiple times in the prism assembly after being emitted to the incident plane from the lens assembly and is reflected to the emergent plane after passing through the stray light improving area. According to the utility model, the stray light improving area is arranged, and the light blocking area is formed in the prism, so that a light path emitted to the outside of the working surface is subjected to diffuse reflection, the continuous reflection intensity of an invalid light path is effectively reduced, the generation of stray light, ghosting and glare is reduced, and the imaging quality is improved.

Description

Technical Field

[0001] This utility model relates to the field of optical imaging technology, and in particular to an optical imaging system, a camera module, and an electronic device. Background Technology

[0002] An optical imaging system is an instrument based on the principle of light refraction. It uses lenses to collect and focus light rays from an object onto a single point to form a clear image. Therefore, it is often used in various camera modules, microscopes, and various industrial inspection fields.

[0003] The optical imaging system of a camera module mainly consists of a lens assembly, a prism assembly, and an image sensor. The lens assembly uses a combination of lenses to precisely focus light from the scene onto the image sensor through refraction, forming an inverted real image. The image sensor then converts the light signal into a point signal to generate the image. The prism assembly, as the core component of the optical imaging system, precisely bends or splits the light path. It is often used in periscope lenses to change the direction of light to achieve telephoto compression and can also participate in color separation or polarization processing. However, because the prism has multiple air-glass interfaces, including the incident and exit surfaces, even with an anti-reflection coating, residual reflected light will still be generated at the edges of the prism assembly, creating ghosting effects through reflection and refraction within the prism assembly. If the total internal reflection slope fails due to coating defects, contamination, or angular deviation, it will directly produce penetrating stray light. Furthermore, stray light scattering from the environment on the non-working surfaces of the prism assembly and the complex reflection paths added after optical path folding make it easier for imaging light to penetrate the sensor, causing unpredictable glare or contrast degradation. Utility Model Content

[0004] In view of the shortcomings of the prior art, the technical problem to be solved by this utility model is to provide an optical imaging system, camera module and electronic device to solve the problem of a large amount of stray light caused by light reflection of prism components.

[0005] To solve the above-mentioned technical problems, the present invention provides an optical imaging system including a lens assembly, an imaging assembly, and a prism assembly. The prism assembly has an incident surface and an exit surface located on the same side. The lens assembly faces the incident surface, and the imaging assembly faces the exit surface. A stray light improvement area is formed on the prism assembly to improve stray light. After light is incident from the lens assembly onto the incident surface, it is reflected multiple times within the prism assembly and then reflected to the exit surface after passing through the stray light improvement area.

[0006] Furthermore, after light enters the prism assembly from the incident surface from various directions, it is reflected to form several different light paths. The light paths are respectively configured as the first light path and the second light path on both sides of the imaging assembly. The first light path and the second light path formed in the prism assembly overlap and intersect to form an intersection area. The stray light improvement area is correspondingly set at the intersection area.

[0007] Furthermore, the prism assembly has a first reflecting surface, a second reflecting surface, and a third reflecting surface. The second reflecting surface is located between and on the same side as the incident surface and the exit surface. After entering the prism assembly from the incident surface, external light rays sequentially strike the first reflecting surface, the stray light improvement area, the second reflecting surface, and the third reflecting surface before exiting from the exit surface. Alternatively, after entering the prism assembly from the incident surface, external light rays sequentially strike the first reflecting surface, the second reflecting surface, the stray light improvement area, and the third reflecting surface before exiting from the exit surface.

[0008] Furthermore, the prism assembly includes a first prism in the shape of a right trapezoid and a second prism in the shape of a right trapezoid. The right-angled faces of the first and second prisms are glued together to form the stray light improvement region. The stray light improvement region includes a screen-printed area for blocking stray light and a light-transmitting area for allowing light to pass through and which is complementary to the screen-printed area. A continuous wavy boundary line for diffuse reflection of light is formed between the screen-printed area and the light-transmitting area.

[0009] Furthermore, the screen-printed area has a U-shaped structure and includes a fully covered section that covers the bottom of the right-angled surface and a half-covered section that covers both sides of the right-angled surface from both sides of the fully covered section toward the top. The light-transmitting area is located between the two half-covered sections, and the boundary line between the light-transmitting area and the fully covered section corresponds to the lowest point of the intersection area.

[0010] Furthermore, the boundary line is formed by alternating and staggered connections of several arcs with a radius of 0.05 mm.

[0011] Furthermore, the prism assembly includes a third prism, which has a bottom surface on the side facing away from the incident and exit surfaces. The stray light improvement area includes a first light-blocking groove recessed on the bottom surface and extending to the intersection area, and a second light-blocking groove symmetrically recessed on both sides of the third prism and staggered from the first light-blocking groove. The first light-blocking groove has a first converging side, on which a plurality of continuous first wave structures for diffuse reflection of light are formed, and the first converging side corresponds to the lowest point of the intersection area. A continuously wavy boundary line for diffuse reflection of light is formed between the screen printing area and the light-transmitting area.

[0012] Furthermore, the stray light improvement area also includes a third light-blocking groove and a fourth light-blocking groove formed on the bottom surface and disposed on both sides of the first light-blocking groove along the optical path. The third light-blocking groove and / or the fourth light-blocking groove have a plurality of continuous second wave structures for diffuse reflection of light.

[0013] This utility model also provides a camera module including a bracket, a stabilization motor, a lens assembly, an imaging assembly, and a prism assembly. The bracket has a mounting surface with a recessed mounting groove. The prism assembly is installed in the mounting groove. The stabilization motor is located on one side of the mounting surface and faces the incident surface. The imaging assembly is located on the other side of the mounting surface and faces the exit surface. The lens assembly is mounted on the stabilization motor.

[0014] This invention also provides an electronic device comprising any of the aforementioned optical imaging systems.

[0015] The optical imaging system, camera module, and electronic device of this invention have at least the following beneficial effects: by setting up a stray light improvement area, a light-blocking area is formed inside the prism, so that the light path pointing out of the working surface is diffusely reflected, effectively reducing the continuous reflection intensity of the invalid light path, reducing the generation of stray light, ghosting, and glare, and improving the imaging quality. Attached Figure Description

[0016] 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:

[0017] Figure 1 This is a front structural diagram of the optical imaging system of this utility model;

[0018] Figure 2 This is a schematic diagram of the prism assembly according to Embodiment 1 of this utility model;

[0019] Figure 3 This is a front structural diagram of the prism assembly of this utility model;

[0020] Figure 4 This is a schematic diagram of the structure of the second prism of this utility model;

[0021] Figure 5 This is a schematic diagram of the optical path of a portion of the optical imaging system according to Embodiment 1 of this utility model;

[0022] Figure 6 This is an irradiance distribution diagram of the image sensor receiving light under various optical path conditions in the optical imaging system of Embodiment 1 of this utility model;

[0023] Figure 7This is a schematic diagram of the prism assembly according to Embodiment 2 of this utility model;

[0024] Figure 8 This is a front structural diagram of the prism assembly of this utility model;

[0025] Figure 9 This is a structural schematic diagram of the prism assembly of this utility model (from another angle);

[0026] Figure 10 for Figure 9 An enlarged schematic diagram of part A shown;

[0027] Figure 11 This is a schematic diagram of the structure of the optical imaging system of this utility model under four optical path conditions, C1-C4;

[0028] Figure 12 This is an irradiance distribution diagram of the light received by the image sensor under four optical path conditions (C1-C4) of the optical imaging system of this utility model;

[0029] Figure 13 This is a schematic diagram of the camera module of this utility model;

[0030] Figure 14 This is a half-sectional schematic diagram of the camera module of this utility model;

[0031] Figure 15 This is an exploded view of the camera module of this utility model;

[0032] Figure 16 This is a schematic diagram of the structure of the dust cover of this utility model;

[0033] Figure 17 This is a schematic diagram of the structure of the bracket of this utility model.

[0034] The meanings of the labels in the attached diagram are as follows:

[0035] Lens assembly 1, reinforcing block 2, adapter slot 21, prism assembly 3, incident surface 311, exit surface 312, first reflecting surface 313, second reflecting surface 314, third reflecting surface 315, top surface 321, bottom surface 322, first side surface 323, second side surface 324, third side surface 325, fourth side surface 326, inking area 33, first inking section 331, second inking section 332, third inking section 333, fourth inking section 334, fifth inking section 335, sixth inking section 336, intersection area 34, lowest point 341, first prism 351, second prism 352, third prism 3 53. Stray light improvement area 36. Screen printing area 361. Full blockage section 3611. Half blockage section 3612. Light transmission area 362. Boundary line 363. First light blocking groove 364. First convergence side 3641. Second light blocking groove 365. Second convergence side 3651. Third light blocking groove 366. Fourth light blocking groove 367. Third convergence side 3671. First wave structure 368. Arc surface 3681. Second wave structure 369. Bracket 4. Mounting surface 41. Mounting groove 42. Anti-shake motor 5. Imaging component 6. Image sensor 61. Chip carrier 62. Filter 63. Circuit board 64. Dust cover 7. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings.

[0037] Please see Figures 1 to 12 The optical imaging system of this utility model includes a lens assembly 1, an imaging assembly 6, and a prism assembly 3. The lens assembly 1 focuses the light from the scene onto the prism assembly 3 by refraction. The prism assembly 3 changes the direction of the light by reflecting the light, thereby achieving long focal length compression and focusing the light onto the imaging assembly 6. The imaging assembly 6 converts the light signal into an electrical signal to generate an image.

[0038] In this embodiment, the lens assembly 1 includes a lens carrier and multiple lenses mounted on the lens carrier. The lenses can be two or more, such as four, arranged sequentially along the optical axis and aligned with the prism assembly 3. In one embodiment, the two lenses closest to the object side have positive optical power, and the two lenses closest to the prism assembly 3 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, allowing for a smoother light transition. The lens assembly 1 is prior art and can be referenced to any lens assembly 1 used in a camera module, particularly a lens assembly 1 for a periscope camera module, which will not be described in detail here.

[0039] In this embodiment, the imaging component 6 includes an image sensor 61 (or chip) for converting optical signals into electrical signals. The image sensor 61 is divided into two sides, with a first side close to the incident surface 311 and a second side away from the incident surface 311.

[0040] In this embodiment, the prism assembly 3 has an incident surface 311 and an exit surface 312. The lens assembly 1 is positioned opposite the incident surface 311, and the imaging assembly 6 is positioned opposite the exit surface 312, so that the lens assembly 1 and the imaging assembly 6 are located on the same side of the prism assembly 3. The prism assembly 3 is trapezoidal, and the incident surface 311 and the exit surface 312 are on the same side, effectively controlling the thickness of the prism assembly 3. Light is emitted from the lens assembly 1 towards the incident surface 311, and after multiple reflections within the prism assembly 3, it is emitted towards the imaging assembly 6 via the exit surface 312. The outer surfaces of the prism assembly 3 are a top surface 321, a bottom surface 322, a first side surface 323, a second side surface 324, a third side surface 325, and a fourth side surface 326. Among them, the top surface 321 and the bottom surface 322 are distributed opposite each other and parallel, and the top surface 321 and the bottom surface 322 are of different lengths. The first side surface 323 and the second side surface 324 are parallel and symmetrically distributed on both sides of the top surface 321 and the bottom surface 322 along their widths. The third side surface 325 and the fourth side surface 326 are symmetrically distributed on both sides of the top surface 321 and the bottom surface 322 along their lengths, so that the prism assembly 3 has an isosceles trapezoidal structure. It should be noted that the structure of the prism assembly 3 is not limited to a trapezoid; it can also be composed of multiple triangular prisms to form an irregular structure, ensuring that the incident surface 311 and the exit surface 312 are on the same side or different sides. Ultimately, the light emitted from the exit surface 312 is focused onto the imaging assembly 6. The angles between the two sides of the top surface 321 of the prism assembly 3 and the third side surface 325 and the fourth side surface 326 are approximately 33°.

[0041] To minimize light loss, improve image quality, and reduce stray light formation during use, ink can be applied to the surface of the prism assembly 3 using methods such as screen printing to form ink-coated areas 33. Each ink-coated area 33 is coated with an AR film. The ink-coated areas 33 include ink coating on the top surface 321, bottom surface 322, first side surface 323, second side surface 324, third side surface 325, and fourth side surface 326. Specifically, the ink-coated areas 33 include a first ink-coated portion 331 formed on the top surface 321, a second ink-coated portion 332 formed on the bottom surface 322, a third ink-coated portion 333 formed on the first side surface 323, a fourth ink-coated portion 334 formed on the second side surface 324, a fourth ink-coated portion 334 formed on the third side surface 325, and a fifth ink-coated portion 335 formed on the fourth side surface 326. A first reflective area is provided at the middle of the first ink coating section 331. This first reflective area has progressively wider first, second, and third portions along the length of the prism assembly 3. Each of these portions is rectangular. The first portion serves as the incident surface 311, corresponding to the size of the lens assembly 1. The third portion serves as the exit surface 312, corresponding to the size of the imaging assembly 6, thus controlling the light intake and exhaust. The ink coating section blocks unwanted stray light. The second portion is configured as the second reflective surface 314. In this way, the ink coating area 33 ensures the formation of the first reflective area, blocking the portion of the top surface 321 located outside the first reflective area, thereby absorbing light rays incident from inside the prism assembly 3 towards the edge and reducing stray light formation. Simultaneously, the first reflective area, wider on one side (the third portion) and narrower on one side (the first portion), prevents misalignment during prism assembly 3 installation. The first, second, and third portions, as well as the first ink coating section 331, are all symmetrically arranged about the central axis of the prism assembly 3 parallel to its length. The dimensional difference in the width direction of the first part, the second part, and the third part can all be set between 0.2-0.6mm. The first part is close to the third side 325, and the third part is close to the fourth side 326. The width of the first ink-coated portion 331 between the first part and the third side 325 is relatively narrow, at 0.29±0.05mm, to ensure that light can more easily hit the third side 325, thereby ensuring that the edges are blocked and stray light is reduced. Since the light is focused by the lens assembly 1 when it enters from the incident surface 311, the range of the light path is relatively small. Therefore, the distance between the first part and the first side 323 and the second side 324 along the width is larger than the distance between the second part and the third part and the first side 323 and the second side 324. Therefore, the ink-coated portion corresponding to the first ink-coated portion 331 is larger, so that while ensuring the light enters, more light can be absorbed from the edges through ink coating. Similarly, the ink-coated portions on both sides of the second part are wider than the ink-coated portions on both sides of the third part, so as to ensure the refraction and expansion range of light on the exit surface 312 as much as possible.The two corners corresponding to one side of the first part near the third side surface 325 are rounded. Since the bottom surface 322 is not used for reflecting light, the second ink coating portion 332 is applied to the entire bottom surface 322. Similarly, since the first side surface 323 and the second side surface 324 are not used for reflecting light, the first side surface 323 and the second side surface 324 are respectively coated with the third ink coating portion 333 and the fourth ink coating portion 334. The fifth ink coating portion 335 is coated on the third side surface 325 and forms a square frame structure along the four sides of the third side surface 325. The first reflective surface 313 is formed on the inner side of the fifth ink coating portion 335. Corresponding to the problem of light being focused on the incident surface 311, the distance between the two sides of the first reflective surface 313 along the width direction and the first side surface 323 and the second side surface 324 is relatively large, such as 1.88±0.05mm. The size of the first reflective surface 313 can be more than twice that. The width of the fifth ink coating portion 335 between the first reflective surface 313 and the top surface 321 and the bottom surface 322 is relatively narrow, such as 0.48±0.05mm. A sixth inking section 336 is formed on the fourth side surface 326. Ink is applied to both sides of the fourth side surface 326 along its width, and a U-shaped sixth inking section 336 is formed on the side of the fourth side surface 326 closest to the bottom surface 322. A third reflecting surface 315 is formed inside the sixth inking section 336. Since the sixth inking section 336 is close to the emitting surface 312, the area of ​​the sixth inking section 336 on both sides of the third reflecting surface 315 along its width is narrower than the area of ​​the fifth inking section 335 on both sides of the width of the first reflecting surface 313. There is no ink applied between the side of the third reflecting surface 315 closest to the top surface 321 and the top surface 321. However, to prevent light from escaping from the connection between the third reflecting surface 315 and the top surface 321, a chamfered surface is formed at this connection, and ink is applied to this chamfered surface. Correspondingly, a chamfered surface can also be provided and ink applied at the connection between the third side surface 325 and the top surface 321. Light rays converge from the lens assembly 1 to the incident surface 311 and then enter the prism assembly 3. The light rays first strike the first reflecting surface 313, and the positions of the rays striking the first reflecting surface 313 vary depending on the angle of the light rays originating from different positions on the lens assembly 1. The light rays sequentially pass through the first reflecting surface 313, the second reflecting surface 314, and the third reflecting surface 315 before exiting from the exit surface 312. Light rays from various directions are focused onto the incident surface 311 after striking the lens assembly 1. Different light rays, after passing through the incident surface 311, enter the prism assembly 3 and are reflected to form several different light paths. Excluding the portion of light absorbed by the ink-coated area 33, a portion of the normally reflected light paths, after being reflected by the prism assembly 3 and exiting the exit surface 312, are directed towards the first side of the imaging assembly 6. The light path ultimately directed towards the first side is configured as the first light path. Figure 1The remaining normally reflected light, after being reflected by the prism assembly 3 and exiting through the exit surface 312, is directed towards the second side of the imaging assembly 6. This final light path directed towards the second side is configured as the second optical path. Figure 1 The blue lines represent the two paths. In this embodiment, both the first and second optical paths pass sequentially through the incident surface 311, the first reflecting surface 313, the second reflecting surface 314, the third reflecting surface 315, and the exit surface 312. However, since the first optical path is closer to the incident surface 311 than the second optical path, and the second optical path is closer to the exit surface 312, the first optical path approaches the incident surface 311 when it travels from the first reflecting surface 313 to the second reflecting surface 314. Therefore, the optical path of the first optical path traveling from the second reflecting surface 314 to the third reflecting surface 315 overlaps and intersects with the optical path of the second optical path traveling from the first reflecting surface 313 to the second reflecting surface 314, forming an intersection region 34 (or a cross region). To ensure the final image consistency of the light in the intersection region 34, a stray light improvement region 36 is provided on the prism assembly 3. The stray light improvement region 36 is correspondingly set on the intersection region 34. By performing light blocking and absorption treatment on the periphery of the intersection region 34, the light is prevented from deflecting when passing through the stray light improvement region 36. The corresponding first light path is directed to the third reflective surface 315 and finally to the first side of the imaging assembly 6, and the corresponding second light path is directed to the second reflective surface 314 and finally to the second side of the imaging assembly 6. This ensures that the brightness of the light received on both sides of the chip is consistent, ensuring uniform brightness after imaging and guaranteeing imaging quality. In this embodiment, the external light rays corresponding to the first optical path enter the prism assembly 3 from the incident surface 311 and are sequentially incident on the first reflecting surface 313, the second reflecting surface 314, the stray light improvement area 36 and the third reflecting surface 315, and then exit from the exit surface 312 to the first side of the imaging assembly 6; the external light rays corresponding to the second optical path enter the prism assembly 3 from the incident surface 311 and are sequentially incident on the first reflecting surface 313, the stray light improvement area 36, ​​the second reflecting surface 314 and the third reflecting surface 315, and then exit from the exit surface 312 to the second side of the imaging assembly 6.

[0042] It should be noted that on the prism assembly 3, the intersection region 34 has a lowest point 341 along the height direction of the prism assembly 3 (i.e., the direction in which the shortest line connecting the top surface 321 and the bottom surface 322 extends). The lowest point 341 is the intersection point of the first optical path and the second optical path on the intersection region 34 that is closest to the bottom surface 322. The stray light improvement region 36 is arranged with this lowest point 341 as a reference.

[0043] In this invention, the Pv of the first reflecting surface 313 and the third reflecting surface 315 is ≤λ / 10, and the Pv of the top surface 321 is ≤λ / 6, where λ is the wavelength, λ = 632.8nm. The non-overflow area of ​​the ink-coated region 33 of the third side surface 325 and the fourth side surface 326 is ≥0.2mm. The transmittance between the incident surface 311 and the first reflecting surface 313 is required to be AOI = 0°, corresponding to a Tavg of ≥82% for 400-700nm; ≥78% for 400-440nm; ≥83% for 441-670nm; and >76% for 671-700nm, to ensure sufficient light intake. The ink coating increases the transmittance of visible light. Edge breaking requirements: The edge breaking depth (diameter of the broken edge surface) in non-inked areas should be <0.05mm, and the edge breaking depth (diameter of the broken edge surface) in inked areas should be <0.1mm. In addition, there should be no more than 3 edges with an edge breaking width >0.15mm. The connection between each side must ensure that there is no light leakage. The top surface 321, bottom surface 322, and first side surface 323 to fourth side surface 326 are coated with ink. Prolonged ink application is not permitted. Ink overflow width is <0.08mm. Internal reflectivity (mean) ≤0.1% (400-700nm), transmittance (mean) ≤0.1% (400-650nm). The bottom surface 322 has an internal reflectivity (mean) ≤0.3% (400-700nm). The top surface 321, third side surface 325, and fourth side surface 326 have an ink reflectivity (maximum) ≤0.5% (400-700nm). After coating, Ra ≤1nm to ensure light shielding, reduce light reflectivity, and minimize stray light generation.

[0044] Example 1

[0045] In this embodiment, the prism assembly 3 includes a first prism 351 and a second prism 352, both in the shape of right-angled trapezoids. The sides of the first prism 351 and the second prism 352 corresponding to the right angles are configured as right-angled surfaces. The first prism 351 and the second prism 352 are glued together through the right-angled surfaces to form a trapezoidal prism assembly 3. The right-angled surfaces of the first prism 351 and the second prism 352 are positioned corresponding to the intersection region 34 of the prism assembly 3. A stray light improvement region 36 is formed on the glued right-angled surfaces and overlaps at the lowest point 341 of the intersection region 34. After corresponding screen printing is applied to the right-angled surfaces, optical adhesive is used to glue the first prism 351 and the second prism 352 together. The optical adhesive must ensure that its refractive index is consistent with the refractive index of the selected prism assembly 3 material, and that its light transmittance reaches 99.7%. The transmittance of the screen-printed area 361 is less than 0.3%, and its reflectance is less than 0.5%, to achieve sufficient light absorption. The glue gap is less than 2 mm.

[0046] In this embodiment, the stray light improvement region 36 includes a screen-printed region 361 for blocking stray light and a light-transmitting region 362 that allows light to pass through and is complementary to the screen-printed region 361, so that the entire right-angled surface is covered by the screen-printed region 361 and the light-transmitting region 362. A continuous wavy boundary line 363 is formed between the screen-printed region 361 and the light-transmitting region 362. When light is incident on the boundary line 363, the wavy structure of the boundary line 363 diffuses the light, improving the diffracted light and correcting some of the deflected light. The screen-printed region 361 blocks stray light. Therefore, the first prism 351 and the second prism 352 have different dimensions in the longitudinal direction, with the first prism 351 being relatively shorter than the second prism 352. This ensures that the stray light improvement region 36 blocks stray light while reducing its impact on image brightness and ensuring consistent image brightness. The screen printing area 361 has a U-shaped structure and includes a fully covered section 3611 that covers the bottom of the right angle surface and a half-covered section 3612 that covers both sides of the right angle surface from both sides of the fully covered section 3611 toward the top. The light-transmitting area 362 is located between the two half-covered sections 3612, and the boundary line 363 between the light-transmitting area 362 and the fully covered section 3611 corresponds to the lowest point 341 of the intersection area 34. The boundary line 363 between the light-transmitting area 362 and the two sides of the fully covered section 3611 corresponds to the edge of the intersection area 34. For example, the dimensions of the right-angled surfaces are 8±0.03mm * 3.02±0.03 (or ±0.02)mm. The dimension between the boundary line 363 and the bottom surface 322 in the fully opaque section 3611 is 1.6±0.05mm, while the dimension between the two sides of the light-transmitting area 362 and the first side 323 or the second side 324, i.e., the dimension of the half-opaque section 3612, is 1.58±0.03mm. The fully opaque section 3611 and the half-opaque section 3612 block stray light. The light rays are directed from the first reflecting surface 313 or the second reflecting surface 314, pass through the light-transmitting area 362, and then strike the second reflecting surface 314 or the third reflecting surface 315. The boundary line 363 is formed by several alternating and staggered arcs with a radius of 0.05 mm. When light strikes the boundary line 363, it forms multiple randomly oriented micro-reflective surfaces, causing the light to scatter at different angles. This creates a spatially uniform distribution of reflected light paths, resulting in localized angular disturbances that disperse the light over a larger solid angle range, suppressing reflection peaks, forming diffuse reflection, and reducing light deflection. Please refer to [link / reference]. Figure 6 B1-B3 are irradiance maps (simulations) corresponding to the three optical paths selected in this embodiment. It can be seen that glare and light spots are effectively improved. Corresponding to B2, the total energy is 9.26E-04, and the maximum irradiance is 8.38E-04. The energy is significantly reduced, there is no ghosting, and stray light is significantly improved. B4-B5 are irradiance maps with a straight line at the boundary 363. Their improvement effect compared to the wavy line is poor, and a large amount of energy, stray light, and glare still exist.

[0047] Example 2

[0048] Please see Figures 7 to 12 In this embodiment, the prism assembly 3 includes a third prism 353, which has a trapezoidal structure and may be an isosceles trapezoid. The stray light improvement region 36 includes a first light-blocking groove 364 recessed on the bottom surface 322 and extending to the intersection region 34, a second light-blocking groove 365 symmetrically recessed on both sides of the third prism 353 and staggered on the first light-blocking groove 364, a third light-blocking groove 366 and a fourth light-blocking groove 367 formed on the bottom surface 322 and disposed on both sides of the first light-blocking groove 364 along the optical path. The first light-blocking groove 364, the second light-blocking groove 365, the third light-blocking groove 366 and the fourth light-blocking groove 367 may all have a V-shaped structure or a U-shaped structure, or other shapes with a gradually narrowing or converging structure on one side. Therefore, the first light-blocking groove 364 has a first converging side 3641 that converges from the bottom surface 322 toward the top surface 321, and the first converging side 3641 corresponds to the lowest point 341 of the intersection region 34. The walls of the first light-blocking groove 364, the second light-blocking groove 365, the third light-blocking groove 366, and the fourth light-blocking groove 367 are all coated with ink to form part of the ink-coated region 33.

[0049] A plurality of continuous first wave structures 368 for diffuse reflection of light are formed on the first convergent side 3641, serving the same function as the boundary line 363 in Embodiment 1. The first wave structures 368 are directly molded on the first convergent side 3641 of the first light-blocking groove, resulting in low roughness and no scattering when light is incident on them. The first wave structures 368 consist of a plurality of regularly spaced arc-shaped surfaces 3681. The middle portion of each arc-shaped surface 3681 arches outward toward the bottom surface 322, while the two ends of each arc-shaped surface 3681 are recessed toward the top surface 321 and adjacent to other arc-shaped surfaces 3681. This allows for multi-angle scattering of light when it is incident on the first wave structures 368, thereby correcting some of the deflected light and effectively reducing stray light formation. The arc-shaped surface 3681 has a dimension of 0.47 mm and a radius of 0.2 ± 0.05 mm, and the radius of the recessed ends of the arc-shaped surface 3681 is 0.15 ± 0.05 mm. The depth of the first light-blocking groove 364 is the same as the width of the full-coverage section 3611 in Embodiment 1, so as to block light outside the intersection area 34. Please refer to Figure 11 C1-C2 represent the optical path distribution structure of the first wave structure 368. As shown in the figure, light is diffusely reflected by the first wave structure 368, reducing light deflection. Please refer to [link / reference]. Figure 12 , Figure 12 C1 is Figure 11 The energy irradiance distribution of light at imaging component 6 in C1 shows that although energy still exists, the intensity of the energy is low, and the stray light phenomenon is improved. Figure 12C2 is Figure 11 C2 corresponds to the energy irradiance distribution, where the energy distribution is significantly reduced. As shown in the figure, after light travels from the incident surface 311 to the first reflecting surface 313, the second reflecting surface 314, and the first wave structure 368, a portion continues to travel to the second reflecting surface 314 and the third reflecting surface 315 before exiting from the exit surface 312. This portion generates some stray light. A portion of the light travels normally from the first wave structure 368 to the third reflecting surface 315 before exiting from the exit surface 312; this portion is the normal light path. Another portion of the light travels from the incident surface 311 to the first reflecting surface 313, the second reflecting surface 314, the light-transmitting area 362, and the third reflecting surface 315 before exiting from the exit surface 312; this portion is also the normal light path.

[0050] Please see Figure 11 and 12The second light-blocking grooves 365 are recessed from the first side surface 323 and the second side surface 324 respectively. The angle between one side wall of the two second light-blocking grooves 365 and the corresponding first side surface 323 and the second side surface 324 is 40°. Both second light-blocking grooves 365 have a second closing side 3651 and close towards each other. The straight-line distance between the second closing side 3651 and the corresponding first side surface 323 and the second side surface 324 is consistent with the width of the half-shading section 3612 in Embodiment 1. Thus, light-blocking areas are formed at the bottom and sides of the third prism 353 to block the light outside the intersection area 34 on both sides and reduce the formation of stray light. Since the light paths differ slightly when reflected within the third prism 353, to further reduce stray light formation, several continuous second wave structures 369 for diffuse reflection are formed on the third light-blocking groove 366 and / or the fourth light-blocking groove 367. The formation and structure of the second wave structures 369 are the same as those of the first wave structure 368. The difference is that the third light-blocking groove 366 and the fourth light-blocking groove 367 are much smaller than the first light-blocking groove 364. The groove wall of the first light-blocking groove 364 is used to block light, while the third light-blocking groove 366 and the fourth light-blocking groove 367 are used to reflect some of the deflected light to reduce stray light formation. Among them, the third light-blocking groove 366 is closer to the third side surface 325, and the fourth light-blocking groove 367 is closer to the fourth side surface 326. The angles between the third light-blocking groove 366 and the bottom surface 322 are 10° and 45° respectively, with the side wall of the groove closest to the third side 325 and the side wall of the groove furthest from the third side 325. The angles between the fourth light-blocking groove 367 and the bottom surface 322 are both 31°. The maximum distance between the third light-blocking groove 366 and the fourth light-blocking groove 367 is 4.484 mm. A second wave structure 369 is provided on the fourth light-blocking groove 367, but not on the third light-blocking groove 366. In another embodiment, the second wave structure 369 can be provided on both the third light-blocking groove 366 and the fourth light-blocking groove 367, and both the third light-blocking groove 366 and the fourth light-blocking groove 367 have a third converging side 3671, on which the second wave structure 369 is formed. Figure 11 C3 in the image corresponds to the optical path distribution structure of the third light-blocking slot 366. C4 is a normal optical path, but stray light appears. Therefore, after the light is directed towards the second reflective surface 314 and the third reflective surface 315, it is partially reflected by the edge part to the second reflective surface 314 and the third reflective surface 315, and then reflected to the imaging component 6, thus forming stray light. Figure 12 C3 corresponds to Figure 11 The energy irradiance distribution of C3 in the middle Figure 12 C4 in the text corresponds to Figure 11The energy irradiance distribution of C4. It can be seen that the light path reflected by the third light-blocking slot 366 no longer has stray light on the imaging component 6, and the effect of the fourth light-blocking slot 367 is similar; the stray light that has not been processed by the stray light improvement area 36 has a higher energy intensity and has a greater impact on image quality.

[0051] Please see Figures 13 to 17 The camera module of this utility model includes a bracket 4, a stabilization motor 5, a lens assembly 1, an imaging assembly 6, and a prism assembly 3. The bracket 4 has a mounting surface 41 with a recessed mounting groove 42. The prism assembly 3 is installed in the mounting groove 42. The stabilization motor 5 is located on one side of the mounting surface 41 and faces the incident surface 311. The imaging assembly 6 is located on the other side of the mounting surface 41 and faces the exit surface 312. The lens assembly 1 is mounted on the stabilization motor 5. The bracket 4 supports the stabilization motor 5, the prism assembly 3, and the imaging assembly 6. The stabilization motor 5 is used for autofocusing the lens assembly 1. The lens assembly 1, the imaging assembly 6, and the prism assembly 3 are all structures in an optical imaging system and will not be described in detail here.

[0052] The bracket 4 has an integrally molded reinforcing rib, which also serves as internal circuitry within the bracket 4 for electrical connection to the image stabilization motor 5 and the imaging assembly 6. The mounting groove 42 conforms to the outer contour of the prism assembly 3 to accommodate it. The image stabilization motor 5, which may be a voice coil motor, is fixedly mounted on the mounting surface 41. To prevent the image stabilization motor 5 from affecting the prism, the side of the image stabilization motor 5 closest to the imaging assembly 6 is suspended above the top surface 321 of the prism assembly 3. The imaging assembly 6 includes an image sensor 61, a chip carrier 62, a filter 63, a circuit board 64, and a connector. The chip carrier 62 is mounted on the mounting surface 41 and surrounds the exit surface 312. Similarly, the side of the chip carrier 62 closest to the image stabilization motor 5 is suspended above and spaced from the top surface 321 of the prism assembly 3. To ensure stability between the image stabilization motor 5 and the chip carrier 62, a reinforcing block 2 is fixedly installed between them. The reinforcing block 2 abuts against the outer wall of the image stabilization motor 5, and an adapter groove 21 is formed on the side of the reinforcing block 2 facing the imaging component 6 to fit the side of the imaging component 6. The two sides of the reinforcing block 2 are fixedly connected to the bracket 4, and the reinforcing block 2 is also suspended relative to the top surface 321 of the prism assembly 3. This abutment between the image stabilization motor 5 and the imaging component 6 makes them more stable. During assembly, after the reinforcing block 2 is installed on the bracket 4, the image stabilization motor 5 and the imaging component 6 are installed in sequence. When installing the imaging component 6, it can be inserted into the adapter groove 21 from the side and then glued together. The light filter 63 faces the exit surface 312 to filter out unwanted light. After passing through the light filter 63, the light is directed to the image sensor 61. The image sensor 61 and the connector are electrically connected to the circuit board 64, which is fixed to the chip carrier 62. The image sensor 61 converts the light signal into an electrical signal for image formation. To protect the lens from dust before assembly, the camera module also includes a dust cover 7, which covers the image stabilization motor 5.

[0053] The electronic device of this invention can be a mobile phone, tablet, or other device with camera functionality. The electronic device of this invention includes the camera module of this invention, and also includes the optical imaging system in any embodiment of this invention.

[0054] The working method of one embodiment of the optical imaging system, camera module and electronic device of this utility model is as follows: After removing the dust cover 7, the anti-shake motor 5 automatically focuses the light. After passing through the lens assembly 1, the light passes through the incident surface 311, the first reflecting surface 313, the second reflecting surface 314 and then through the light-transmitting area 362. A small amount of light is directed onto the boundary line 363, which diffusely reflects the deflected light. Then the light is directed onto the third reflecting surface 315 and then onto the filter 63 from the exit surface 312. After being filtered by the filter 63, the light is directed onto the image sensor 61 until the image sensor 61 processes the light signal.

[0055] Compared with the prior art, the optical imaging system, camera module and electronic equipment of this invention effectively reduce light deviation and reduce the generation of stray light by setting up a stray light improvement area 36 and using a wave-shaped structure to diffuse light from multiple angles.

Claims

1. An optical imaging system, comprising a lens assembly, an imaging assembly, and a prism assembly, characterized in that: The prism assembly has an incident surface and an exit surface located on the same side. The lens assembly faces the incident surface, and the imaging assembly faces the exit surface. A stray light improvement area is formed on the prism assembly to improve stray light. After light is incident from the lens assembly to the incident surface, it is reflected multiple times in the prism assembly and then reflected to the exit surface after passing through the stray light improvement area.

2. The optical imaging system as described in claim 1, characterized in that: Light enters the prism assembly from the incident surface from various directions and is reflected to form several different light paths. The light paths are respectively configured as the first light path and the second light path on both sides of the imaging assembly. The first light path and the second light path formed in the prism assembly overlap and intersect to form an intersection area. The stray light improvement area is correspondingly set at the intersection area.

3. The optical imaging system as described in claim 2, characterized in that: The prism assembly has a first reflecting surface, a second reflecting surface, and a third reflecting surface. The second reflecting surface is located between and on the same side as the incident surface and the exit surface. External light enters the prism assembly from the incident surface and is sequentially incident on the first reflecting surface, the stray light improvement area, the second reflecting surface, and the third reflecting surface before exiting from the exit surface; or external light enters the prism assembly from the incident surface and is sequentially incident on the first reflecting surface, the second reflecting surface, the stray light improvement area, and the third reflecting surface before exiting from the exit surface.

4. The optical imaging system as described in claim 2 or 3, characterized in that: The prism assembly includes a first prism in the shape of a right trapezoid and a second prism in the shape of a right trapezoid. The right-angled faces of the first and second prisms are glued together to form the stray light improvement region. The stray light improvement region includes a screen-printed area for blocking stray light and a light-transmitting area for allowing light to pass through and which is complementary to the screen-printed area. A continuous wavy boundary line for diffuse reflection of light is formed between the screen-printed area and the light-transmitting area.

5. The optical imaging system as described in claim 4, characterized in that: The screen-printed area has a U-shaped structure and includes a fully covered section that covers the bottom of the right angle and a half-covered section that covers both sides of the right angle from the sides of the fully covered section toward the top. The light-transmitting area is located between the two half-covered sections, and the boundary line between the light-transmitting area and the fully covered section corresponds to the lowest point of the intersection area.

6. The optical imaging system as described in claim 4, characterized in that: The boundary line is formed by several arcs with a radius of 0.05 mm that are alternately and staggered.

7. The optical imaging system as described in claim 4, characterized in that: The prism assembly includes a third prism with a bottom surface on the side facing away from the incident and exit surfaces. The stray light improvement area includes a first light-blocking groove recessed on the bottom surface and extending to the intersection area, and a second light-blocking groove symmetrically recessed on both sides of the third prism and staggered from the first light-blocking groove. The first light-blocking groove has a first converging side, on which a plurality of continuous first wave structures for diffuse reflection of light are formed, and the first converging side corresponds to the lowest point of the intersection area. A continuously wavy boundary line for diffuse reflection of light is formed between the screen printing area and the light-transmitting area.

8. The optical imaging system as described in claim 7, characterized in that: The stray light improvement area also includes a third light-blocking groove and a fourth light-blocking groove formed on the bottom surface and disposed on both sides of the first light-blocking groove along the optical path. Several continuous second wave structures for diffuse reflection of light are formed on the third light-blocking groove and / or the fourth light-blocking groove.

9. A camera module, characterized in that: The device includes a bracket, a stabilization motor, and a lens assembly, an imaging assembly, and a prism assembly as described in any one of claims 1 to 8. The bracket has a mounting surface with a recessed mounting groove. The prism assembly is mounted in the mounting groove. The stabilization motor is disposed on one side of the mounting surface and faces the incident surface. The imaging assembly is disposed on the other side of the mounting surface and faces the exit surface. The lens assembly is mounted on the stabilization motor.

10. An electronic device, characterized in that: Includes the optical imaging system as described in any one of claims 1 to 8.

Images