Long-focus optical system

Abstract

The invention discloses a long-focus optical system. The long-focus optical system comprises an optical lens; the light turning element comprises a first prism, a second prism and a third prism, the second prism is located between the first prism and the third prism, and the first prism and the third prism are prisms of a non-symmetric structure; a first light shielding film disposed between the first prism and the second prism; a second light shielding film disposed between the second prism and the third prism; the first shading film and the second shading film extend from one side of the light turning element to the opposite side of the light turning element, and the first shading film and the second shading film have different heights; light rays emitted from the optical lens are reflected for multiple times in the light turning element and then reach the light sensing chip, and the light sensing chip and the optical lens are arranged on the same side of the light turning element. And the performance requirement of the telephoto lens is met by adopting the thin prism.

Description

Technical Field

[0001] The present application relates to the technical field of camera modules, and in particular to a telephoto optical system. Background Art

[0002] In recent years, with the popularity of portable electronic devices such as smart phones and smart watches, the camera performance of the devices has attracted more and more attention from the market. In order to meet the market demand for telephoto and super telephoto camera performance, telephoto lenses have emerged. The thickness of the prism in the telephoto lens will greatly affect the thickness of the telephoto lens. Therefore, how to meet the performance requirements of the telephoto lens while using a thinner prism is a technical problem that needs to be solved urgently. Summary of the invention

[0003] One object of the present application is to provide a telephoto optical system that overcomes the deficiencies of the prior art and can both reduce the thickness of the prism and meet the performance requirements of the telephoto optical system.

[0004] According to one aspect of the present application, a telephoto optical system is provided, comprising: an optical lens; a light deflection element, comprising: a first prism, a second prism and a third prism, the second prism being located between the first prism and the third prism, the first prism and the third prism being prisms of asymmetric structures; a first light-shielding film being arranged between the first prism and the second prism; a second light-shielding film being arranged between the second prism and the third prism; the first light-shielding film and the second light-shielding film extending from one side of the light deflection element toward the opposite side of the light deflection element, wherein the first light-shielding film and the second light-shielding film have different heights; and a photosensitive chip, the light emitted from the optical lens reaches the photosensitive chip after multiple reflections in the light deflection element, and the photosensitive chip and the optical lens are arranged on the same side of the light deflection element.

[0005] In some embodiments, the first light-shielding film and the second light-shielding film are asymmetric within the light-redirecting element relative to a center line of a lower surface of the light-redirecting element.

[0006] In some embodiments, the first prism and the second prism have a first bonding surface and a second bonding surface for bonding to each other, and the second prism and the third prism have a third bonding surface and a fourth bonding surface for bonding to each other; the first light-shielding film is arranged on the first bonding surface or the second bonding surface, and the second light-shielding film is arranged on the third bonding surface or the fourth bonding surface.

[0007] In some embodiments, the first prism includes a first light incident surface, a first light emitting surface, a first surface and a first reflecting surface which are sequentially connected to form a trapezoidal structure; the second prism includes a second light incident surface, a second reflecting surface, a second light emitting surface and a second surface which are sequentially connected to form a rectangular structure; the third prism includes a third light incident surface, a third surface, a third reflecting surface and a third light emitting surface which are sequentially connected to form a trapezoidal structure; wherein the first light emitting surface is the first bonding surface for bonding the first prism and the second prism to each other, the second light incident surface is the second bonding surface for bonding the first prism and the second prism to each other, the second light emitting surface is the third bonding surface for bonding the second prism and the third prism to each other, and the third light incident surface is the fourth bonding surface for bonding the second prism and the third prism to each other.

[0008] In some embodiments, the first light incident surface and the first reflective surface are connected via a plane or a curved surface; the third light emitting surface and the third reflective surface are connected via a plane or a curved surface.

[0009] In some embodiments, the first light shielding film and the second light shielding film are in a "U"-shaped structure with an opening, and the opening directions of the first light shielding film and the second light shielding film are the same.

[0010] In some embodiments, the first light shielding film and the second light shielding film are arranged parallel to each other in the light deflection element, and the distance between the first light shielding film and the second light shielding film ranges from 1.4 mm to 1.8 mm.

[0011] In some embodiments, a ratio of a height of the first light shielding film to a height of the light turning element ranges from 0.4726 to 0.6300.

[0012] In some embodiments, the height of the first light shielding film ranges from 1.908 mm to 2.371 mm, and the height of the second light shielding film ranges from 0.98 mm to 1.65 mm.

[0013] In some embodiments, the first light shielding film and the second light shielding film are formed by a deposition and etching process or a silk screen process.

[0014] Other embodiments and features are partially described in the following description, and those skilled in the art will understand after reviewing the specification or learn these embodiments and features through practice of the disclosed subject matter. A further understanding of the features and advantages of the present disclosure can be achieved by reference to the remainder of the specification and drawings which constitute a part of this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1is a schematic structural diagram of a telephoto camera module according to an embodiment of the present application;

[0016] Figure 2 is a schematic diagram of a telephoto optical system according to an embodiment of the present application;

[0017] Figure 3 It is a schematic diagram of the structure of the integrated prism cutout;

[0018] Figure 4 is a structural schematic diagram of a split light deflection element according to an embodiment of the present application;

[0019] Figure 5A is along Figure 4 A schematic cross-sectional view of the light turning element along line A-A';

[0020] Figure 5B yes Figure 5A Enlarged schematic diagram of the middle circular area;

[0021] Figure 6 is a schematic structural diagram of a split light deflection element according to another embodiment of the present application;

[0022] Fig. 7A is along Figure 6 A schematic cross-sectional view of the light turning element of line BB';

[0023] Figure 7B yes Fig. 7A Enlarged schematic diagram of the middle circular area;

[0024] Figure 8 is a schematic diagram of the position of a midline O of the lower surface of a light shielding film and a light turning element according to an embodiment of the present application;

[0025] Fig. 9 is a process flow chart of manufacturing a light turning element according to an embodiment of the present application;

[0026] Fig.10 is a manufacturing process flow chart of a light deflection element according to another embodiment of the present application;

[0027] Fig.11 It is a schematic diagram of step S23 and step S25 in a manufacturing process of a light deflection element according to another embodiment of the present application. DETAILED DESCRIPTION

[0028] Below, the present application is further described in conjunction with specific implementation methods. It should be noted that, under the premise of no conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0029] The term "comprising" is open ended. As used in the appended claims, the term does not exclude additional structures or steps.

[0030] In the description of the present application, it should be noted that directional words, such as the terms "center", "lateral", "longitudinal", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, which are only for the convenience of narrating the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as limiting the specific scope of protection of the present application.

[0031] It should be noted that the terms "first", "second", etc. in the description and claims of the present application are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence.

[0032] The terms "including" and "having" and any variations thereof in the specification and claims of this application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or apparatus comprising a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products or apparatuses.

[0033] It should be noted that, as used in this application, the terms "substantially", "approximately" and similar terms are used as terms to express approximation rather than as terms to express degree, and are intended to account for the inherent deviations in measurements or calculations that would be recognized by a person of ordinary skill in the art.

[0034] In the description of this application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, a contact connection, or an indirect connection through an intermediate medium, and it can be the internal connection of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0035] "Configured to" various units, circuits, or other components may be described or recited as "configured to" perform one or more tasks. In such contexts, "configured to" is used to imply a structure (e.g., circuitry) by indicating that the unit / circuit / component includes the structure that performs the one or more tasks during operation. In addition, "configured to" may include general structures (e.g., general circuitry) manipulated by software and / or firmware to operate in a manner that is capable of performing the one or more tasks to be solved. "Configured to" may also include adjusting a manufacturing process (e.g., a semiconductor fabrication facility) to manufacture a device (e.g., an integrated circuit) suitable for implementing or performing one or more tasks.

[0036] The terms used in the description herein are only for describing specific embodiments and are not intended to be limiting. As used in the specification and the appended claims, the singular forms of "one", "a kind of" and "the" are intended to also cover the plural forms, unless the context clearly indicates otherwise. It will also be understood that the term "and / or" used herein refers to and covers any and all possible combinations of one or more items in the items listed in association. It will also be understood that the terms "including" and / or "comprising" when used in this specification specify the presence of stated features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or their grouping.

[0037] As used herein, the term "if" may be interpreted to mean "when" or "upon" or "in response to determining" or "in response to detecting," depending on the context. Similarly, the phrases "if it is determined that" or "if [a stated condition or event] is detected" may be interpreted to mean "upon determining that" or "in response to determining that" or "upon detecting [a stated condition or event]" or "in response to detecting [a stated condition or event]," depending on the context.

[0038] A telephoto camera module refers to a camera module with a long focal length, which can clearly capture subjects at a long distance. However, due to its relatively long focal length, a telephoto camera module requires a longer total optical lens length (TTL).

[0039] The addition of TTL will increase the size of the camera module, making it unsuitable for integration in small mobile devices.

[0040] Various embodiments of the present application relate to prisms for use in optical systems of telephoto camera modules that are suitable for integration into small mobile devices. Figure 1As shown, the optical system may include an optical lens 10 having one or more lenses, a light deflection element 30, and a photosensitive chip 20. In some embodiments, the light deflection element 30 has multiple reflective surfaces so that the light entering the light deflection element 30 can be reflected multiple times to reach the photosensitive chip 20, which can effectively increase the optical TTL, so that the optical system is suitable for capturing objects at a long distance and providing high-quality images of the distant objects. In some embodiments, the light deflection element 30 may have an elongated shape, and the length extending in the horizontal direction is greater than the height extending in the height direction, so as to reduce the height of the telephoto camera module while maintaining an effective TTL, thereby meeting the demand for miniaturization of the telephoto camera module. Wherein, TTL refers to the distance along the optical axis between the front vertex of the light incident side (facing the object) of the optical lens 10 of the camera module and the imaging surface of the photosensitive chip 20 of the camera module. In some embodiments, the light deflection element 30 may be a single integrated prism. In some embodiments, the light deflection element 30 may be a split prism, for example, the split prism may be a prism formed by combining at least two prisms.

[0041] like Figure 2 As shown, in one embodiment of the present application, the light deflection element 30 includes an upper surface 301, a lower surface 303, and at least two side surfaces 302 connected between the upper surface 301 and the lower surface 303, wherein at least three of the upper surface 301, the lower surface 303, and the at least two side surfaces 302 are surfaces with a reflective function. For example, a reflective coating is disposed on at least three of the upper surface 301, the lower surface 303, and the at least two side surfaces 302 of the light deflection element 30, or a reflector is disposed, so that light can be reflected on the surface of the light deflection element 30 with a reflective function.

[0042] In one embodiment of the present application, the light deflection element 30 is implemented as a trapezoidal prism, and the trapezoidal prism includes an upper surface 301, a lower surface 303, and a first side surface 3021 and a second side surface 3022 connecting the upper surface 301 and the lower surface 303, wherein the upper surface 301 and the lower surface 303 are parallel to each other, the length of the upper surface 301 is greater than the length of the lower surface 303, and the plane where the first side surface 3021 is located intersects with the plane where the second side surface 3022 is located. It should be understood that the trapezoidal prism may include a prism with a trapezoidal cross section, and may also include a prism with a cross section that is approximately trapezoidal. A prism with a cross section that is approximately trapezoidal means that the exposed edges and corners of the prism are removed during the manufacturing process of the prism, for example, the angle between the upper surface 301 and at least two side surfaces 302 is removed, so that the upper surface 301 and at least two side surfaces 302 are connected by a plane or an arc surface, which can avoid the collision and fragmentation of the prism on the one hand, and reduce the length of the prism on the other hand without affecting the propagation of light. In one embodiment of the present application, Figure 4 and Figure 5A As shown, the cross section refers to the cross section formed along the A-A' line direction. In another embodiment of the present application, as Figure 6 and Fig. 7A As shown, the cross section refers to the cross section formed along the BB' line direction.

[0043] In the telephoto camera module, Figure 1 As shown, it includes an optical lens 10, a light deflection element 30 and a photosensitive chip 20. The light deflection element 30 is arranged between the optical lens 10 and the photosensitive chip 20. The light deflection element 30 folds the light emitted from the optical lens 10 and guides it to the photosensitive chip 20, so as to perform imaging through the photosensitive chip 20 to obtain image information.

[0044] In a specific example of the present application, the photosensitive chip 20 and the optical lens 10 are arranged on the same side of the light deflection element 30, so that the height dimension of the camera module only needs to consider the sum of the height dimension of one of the photosensitive chip 20 and the optical lens 10 and the height dimension of the light deflection element 30, without having to simultaneously superimpose the heights of the optical lens 10, the light deflection element 30 and the photosensitive chip 20. In this way, the height dimension of the camera module can be reduced.

[0045] In one embodiment of the present application, Figure 2 As shown, the upper surface 301 of the light deflection element 30 includes a light entrance area 3011, a light exit area 3013, and a reflection area 3012 disposed between the light entrance area 3011 and the light exit area 3013. The optical lens 10 faces the light entrance area 3011 of the upper surface 301, and the photosensitive chip 20 faces the light exit area 3013 of the upper surface 301, so that the light emitted from the optical lens 10 reaches the photosensitive chip 20 after multiple reflections in the light deflection element 30. The light entrance area 3011 and the light exit area 3013 are not provided with a reflective coating, so that the light can enter the light deflection element 30 from the light entrance area 3011 and exit the light deflection element 30 from the light exit area 3013. The reflection area 3012 is provided with a reflective coating, so that the light is reflected under the phenomenon of total reflection when passing through the reflection area 3012.

[0046] It should be understood that when the incident angle of the light is close to or greater than a certain limiting angle (called the critical angle), total reflection may occur. The incident angle refers to the angle between the light incident on the surface and the line perpendicular to the surface at the incident point (called the normal). Therefore, when the incident angle of the light is less than the critical angle, the light entrance area 3011 and the light exit area 3013 of the upper surface 301 of the light deflection element 30 can allow the light to pass through; when the incident angle of the light is close to or greater than the critical angle, the reflection area 3012 of the upper surface 301 of the light deflection element 30 can reflect the light.

[0047] In one embodiment of the present application, Figure 2 As shown, the light turning element 30 can reflect the light in the light turning element 30 an odd number of times to guide the light from the optical lens 10 to pass through the light turning element 30 to reach the photosensitive chip 20. When the light is reflected three times in the light turning element 30, the light passes through the light entrance area 3011 of the upper surface 301 to enter the light turning element 30; at least some of the light passing through the light entrance area 3011 of the upper surface 301 is reflected at the first side surface 3021; ​​at least some of the light reflected from the first side surface 3021 is reflected at the reflection area 3012 of the upper surface 301; at least some of the light reflected from the reflection area 3012 of the upper surface 301 is reflected at the second side surface 3022; so that the light passes through the light exit area 3013 of the upper surface 301 to reach the photosensitive chip 20.

[0048] It should be understood that for an optical system, stray light from the environment can enter the optical system from various directions of the camera module. When external stray light enters the optical system, it will cause glare and affect the imaging effect. Therefore, in order to solve the above problem, in the present application, the light deflection element 30 further includes a shading film 31, which is arranged inside the light deflection element 30 and / or on the surface of the light deflection element 30 to reduce stray light from entering the light deflection element 30 and reduce the generation of glare. Among them, the shading film 31 can be implemented as a shading coating, a dark paint, such as black, ink, etc.

[0049] It should be understandable that Figure 3 As shown, in the present application, when the light deflection element 30 is implemented as an integrated prism, it is usually necessary to set the following in the integrated prism: Figure 3 The cutout 33 is shown, and a light shielding film 31 is arranged in the cutout 33 to achieve the purpose of shielding stray light. The cutout 33 is formed by using a cutting tool to cut from the surface of the light deflection element 30 into the interior of the light deflection element 30, and coating the cutout 33 and / or one or more inner surfaces of the cutout 33 with a material to produce the light shielding film 31, so that the light shielding film 31 can cover the stray light area, shield the light path of the stray light, and prevent the stray light from reaching the photosensitive chip 20 and affecting the imaging effect.

[0050] However, in this way of forming the cutout 33, the size of the cutting tool will cause the cutout 33 to have a certain thickness and depth, and as the depth of the cutout 33 increases, the thickness of the cutout 33 will increase, which will cause the thickness of the coating material disposed in the cutout 33 to increase, and then the thickness of the light shielding film 31 generated by the coating material will also increase, making it easier for the light shielding film 31 to block some effective light, thereby affecting the imaging effect of the photosensitive chip 20. Furthermore, the existence of the cutout 33 will also destroy the structural strength of the integrated prism, making the integrated prism easier to break.

[0051] Therefore, in one embodiment of the present application, Figures 4 to 8 As shown, the light deflection element 30 is implemented as a split prism. For example, the split prism can be a light deflection element 30 formed by combining at least two prisms by, for example, optically transparent adhesive or snap-fitting. When the light deflection element 30 is implemented as a split structure, a light shielding film 31 can be directly arranged between at least two prisms, and there is no need to arrange the cutout 33. This not only simplifies the arrangement process of the light shielding film 31, but also avoids increasing the thickness of the light shielding film 31, so that the light shielding film 31 will not block the light path of effective light while blocking the light path of stray light, thereby avoiding affecting the imaging effect of the photosensitive chip 20. Furthermore, in the process of combining at least two prisms to form the light deflection element 30, the relative positions of at least two prisms can be adjusted so that the split prism has better optical performance in the optical system.

[0052] Furthermore, since there will be consistency fluctuations between prisms during the batch manufacturing process of prisms, it is difficult to ensure that the two prisms are mutually symmetrical structures. Therefore, in the present application, at least two prisms with non-symmetrical structures are combined to form the light deflection element 30, which can not only reduce the manufacturing requirements, but also reduce the defective rate. Moreover, during the assembly process of the light deflection element 30, the relative positions of the at least two prisms with non-symmetrical structures are adjusted so that the assembled light deflection element 30 has better optical performance in the optical system.

[0053] In one embodiment of the present application, the light deflection element 30 includes a first prism 34a and a second prism 35a. In this example, the light deflection element 30 may be trapezoidal in shape, and thus may be composed of two trapezoidal prisms of asymmetric structure; or, it may be formed by using a triangular prism and a trapezoidal prism. In another embodiment of the present application, the light deflection element 30 includes a first prism 34b, a second prism 35b and a third prism 36b. The light deflection element 30 may be trapezoidal in shape, and thus may be composed of two trapezoidal prisms of asymmetric structure and a rectangular prism; or, it may be formed by using a triangular prism, a rectangular prism and a trapezoidal prism. Of course, in other embodiments of the present application, the light deflection element 30 may also include a fourth prism, a fifth prism, and so on, and the present application does not limit this.

[0054] It is worth mentioning that when the light deflection element 30 is implemented as a split prism, the assembly accuracy of at least two prisms will affect the performance of the light deflection element 30. Therefore, in one embodiment of the present application, a manufacturing process of the light deflection element 30 is provided, which can not only simplify the manufacturing process of the light shielding film 31, but also adjust the relative positions of at least two prisms with non-symmetrical structures during the assembly process of the light deflection element 30, so that the assembled light deflection element 30 has better optical performance in the optical system.

[0055] like Fig. 9 The manufacturing process of the light deflection element 30 includes the following steps:

[0056] S11: Provide at least two prisms, wherein the at least two prisms have a first gluing surface 304 and a second gluing surface 305 for gluing to each other.

[0057] S12 : providing at least one light shielding film 31 , wherein the at least one light shielding film 31 is disposed on the first bonding surface 304 or the second bonding surface 305 .

[0058] S13: Calibrate the relative positions of at least two prisms.

[0059] S14: An adhesive medium 32 is disposed between the first gluing surface 304 and the second gluing surface 305 of at least two prisms.

[0060] S15 : curing the adhesive medium 32 , and maintaining at least two prisms at relative positions determined by calibration to form a light deflection element 30 .

[0061] It should be understood that the steps S11 to S14 in the present application do not represent a sequential relationship, but only represent that the manufacturing process of the light deflection element 30 includes the above steps. For example, step S13 may be before step S14 or after step S14.

[0062] In one embodiment of the present application, Figures 4 to 5B , the light deflection element 30 includes two prisms as an example. In the above step S11, at least two prisms include a first prism 34a and a second prism 35a, wherein the first prism 34a and the second prism 35a are prisms with asymmetric structures. Figure 4 As shown, the first prism 34a is implemented as a first trapezoidal prism, and the second prism 35a is implemented as a second trapezoidal prism. In the cross-sectional view of the light deflection element 30, the first prism 34a and the second prism 35a are asymmetric about the center line O of the lower surface 303 of the light deflection element 30.

[0063] Specifically, the first prism 34a includes a first light incident surface 341a, a first light emitting surface 344a, a first surface 343a and a first reflecting surface 342a, wherein the first light incident surface 341a, the first light emitting surface 344a, the first surface 343a and the first reflecting surface 342a are sequentially connected to form a trapezoidal structure, the first light incident surface 341a and the first surface 343a are parallel to each other, the first reflecting surface 342a is connected between the first light incident surface 341a and the first surface 343a, and the first light emitting surface 344a is connected between the first light incident surface 341a and the first surface 343a. The first light emitting surface 344a is a first bonding surface 304 for bonding the first prism 34a and the second prism 35a to each other. It should be understood that, as mentioned above, in order to reduce the possibility of the first prism 34a being broken, the angle between the first light incident surface 341a and the first reflection surface 342a can be removed so that the first light incident surface 341a and the first reflection surface 342a are connected by a plane or an arc surface.

[0064] The second prism 35a includes a second light incident surface 351a, a second surface 352a, a second reflection surface 353a, and a second light emitting surface 354a, wherein the second light incident surface 351a, the second surface 352a, the second reflection surface 353a, and the second light emitting surface 354a are sequentially connected to form a trapezoidal structure, the second light emitting surface 354a and the second surface 352a are parallel to each other, the second reflection surface 353a is connected between the second light emitting surface 354a and the second surface 352a, and the second light incident surface 351a is connected between the second light emitting surface 354a and the second surface 352a. The second light incident surface 351a of the second prism 35a is a second bonding surface 305 for bonding the first prism 34a and the second prism 35a to each other. It should be understood that, as mentioned above, in order to reduce the possibility of the second prism 35a breaking, the angle between the second light emitting surface 354a and the second reflecting surface 353a can be removed so that the second light emitting surface 354a and the second reflecting surface 353a are connected by a plane or an arc surface.

[0065] When the first prism 34a and the second prism 35a are combined to form a light deflection element 30, the first light incident surface 341a of the first prism 34a and the second light emitting surface 354a of the second prism 35a constitute the upper surface 301 of the light deflection element 30, and the first reflection surface 342a of the first prism 34a and the second reflection surface 353a of the second prism 35a constitute the two side surfaces 302 of the light deflection element 30. The first surface 343a of the first prism 34a and the second surface 352a of the second prism 35a constitute the lower surface 303 of the light deflection element 30.

[0066] Furthermore, the first light emitting surface 344a of the first prism 34a and the second light incident surface 351a of the second prism 35a have the same size, so that the first light emitting surface 344a and the second light incident surface 351a are more consistent when they are bonded. Figure 5A In the cross-sectional view shown, the length of the first surface 343a of the first prism 34a is different from the length of the second surface 352a of the second prism 35a, and the length of the first light incident surface 341a of the first prism 34a is different from the length of the second light emitting surface 354a of the second prism 35a.

[0067] In step S12: the light shielding film 31 can be arranged between the first prism 34a and the second prism 35a for gluing to each other on the first gluing surface 304 or the second gluing surface 305. For example, the light shielding film 31 can be arranged on the first gluing surface 304 of the first prism 34a, i.e., the first light emitting surface 344a, or the light shielding film 31 can be arranged on the second gluing surface 305 of the second prism 35a, i.e., the second light incident surface 351a. In this way, the arrangement process of the light shielding film 31 is simpler, and the thickness of the light shielding film 31 is more controllable, which can avoid the situation where the effective light is blocked due to the large thickness of the light shielding film 31.

[0068] Specifically, Figure 5A and Figure 5B As shown, the light shielding film 31 includes a first light shielding film 311, and the first light shielding film 311 is arranged on the first light emitting surface 344a or the second light incident surface 351a which are glued to each other. For example, in a specific example of the present application, when the first light shielding film 311 is arranged on the first light emitting surface 344a of the first prism 34a, the first light shielding film 311 extends from the side where the first surface 343a is located along the height direction toward the side where the first light incident surface 341a is located, and the first light shielding film 311 has a "U"-shaped structure with an opening, and the direction of the opening is toward the side where the first light incident surface 341a is located. For example, in another specific example of the present application, when the first light shielding film 311 is arranged on the second light incident surface 351a of the second prism 35a, the first light shielding film 311 extends from the side where the second surface 352a is located along the height direction toward the side where the second light emitting surface 354a is located, and the first light shielding film 311 has a "U"-shaped structure with an opening, and the direction of the opening is toward the side where the second light emitting surface 354a is located.

[0069] In one embodiment of the present application, when the first prism 34a and the second prism 35a are combined to form a light deflection element 30, the first light shielding film 311 is disposed inside the light deflection element 30 and extends from the lower surface 303 of the light deflection element 30 toward the upper surface 301 of the light deflection element. The first light shielding film 311 has a certain extension height in the light deflection element 30, wherein the ratio of the height of the first light shielding film 311 to the height of the light deflection element 30 is in the range of 0.4726 to 0.6300. It should be understood that 0.4726 to 0.6300 includes the end values ​​0.4726 and 0.6300. In a specific example of the present application, the height of the first light shielding film is 2.371 mm, the height of the light deflection element is 4.1 mm, and the ratio of the height of the first light shielding film 311 to the height of the light deflection element 30 is 0.5783.

[0070] In the present application, when the first light shielding film 311 is a "U"-shaped structure with an opening, the first light shielding film 311 has a structure located at the side of the opening and a structure located at the bottom of the opening. The height of the first light shielding film 311 described in the present application refers to the height of the structure located at the bottom of the opening.

[0071] Furthermore, when the camera module performs optical focusing or optical image stabilization, the optical path of the light propagating in the light deflection element 30 may also change, which may cause the light deflection element 30 to generate stray light that cannot be blocked by the first light shielding film 311. Moreover, tolerances may also be generated during the manufacturing process of the light deflection element 30. The existence of tolerances may also cause the light deflection element 30 to generate stray light that cannot be blocked by the first light shielding film 311. Therefore, in the present application, a certain height margin is provided for the first light shielding film 311 so that when the light path of the stray light reaches the limit, the first light shielding film 311 can still block the light path of the stray light. In a specific embodiment of the present application, the height range of the first light shielding film 311 is: 1.908mm to 2.371mm, wherein the height margin of the first light shielding film 311 is 0.463mm. It should be understood that 1.908mm to 2.371mm includes the end values ​​1.908mm and 2.371mm.

[0072] In the step S13, it is worth mentioning that before the first prism 34a and the second prism 35a are bonded and cured by the bonding medium 32, the relative position of the first prism 34a and the second prism 35a needs to be calibrated so that the assembled light deflection element 30 has better optical performance in the optical system. It should be understood that the relative position of the first prism 34a and the second prism 35a can be adjusted in multiple degrees of freedom (e.g., six-axis adjustment), including but not limited to translation adjustment, rotation adjustment, tilt adjustment, etc. between the first prism 34a and the second prism 35a.

[0073] Specifically, calibrating the relative position of the first prism 34a and the second prism 35a includes adjusting the center of the first light emitting surface 344a of the first prism 34a to align with the center of the second light incident surface 351a of the second prism 35a, wherein the accuracy range of the center alignment of the first light emitting surface 344a and the second light incident surface 351a is ±25um.

[0074] Specifically, calibrating the relative position of the first prism 34a and the second prism 35a includes adjusting the inclination between the first light emitting surface 344a of the first prism 34a and the second light incident surface 351a of the second prism 35a, so as to ensure that the first light emitting surface 344a and the second light incident surface 351a are parallel to each other as much as possible. The accuracy range of the inclination between the first light emitting surface 344a and the second light incident surface 351a is less than 5um.

[0075] Specifically, calibrating the relative position of the first prism 34a and the second prism 35a includes adjusting the degree of rotation between the first light-emitting surface 344a of the first prism 34a and the second light-entering surface 351a of the second prism 35a, so that each side and each corner of the first light-emitting surface 344a is aligned with each side and each corner of the second light-entering surface 351a. The accuracy range of the degree of rotation of the first light-emitting surface 344a and the second light-entering surface 351a is ±25um.

[0076] It should be understood that the above accuracy range can also be referred to as an assembly tolerance range of the first prism 34a and the second prism 35a that can be accepted by the optical system.

[0077] In one embodiment of the present application, step S14 can be implemented before step S13, or can be implemented after step S13. The bonding medium 32 includes a first bonding medium 321. In one embodiment of the present application, the relative position of the first prism 34a and the second prism 35a can be adjusted first to align the first prism 34a and the second prism 35a; then the first bonding medium 321 is set on the first bonding surface 304 or the second bonding surface where the first prism 34a and the second prism 35a are bonded to each other; then the first bonding surface 304 is bonded to the second bonding surface 305 by the first bonding medium 321; finally, the first bonding medium 321 is cured to keep the first prism 34a and the second prism 35b at the relative position determined by calibration to form the light turning element 30.

[0078] In another embodiment of the present application, a first adhesive medium 321 can be firstly set on the first bonding surface 304 or the second bonding surface 305 where the first prism 34a and the second prism 35a are bonded to each other; then the relative position of the first prism 34a and the second prism 35a is adjusted; then the first bonding surface 304 and the second bonding surface 305 are bonded by the first adhesive medium 321; finally, the first adhesive medium 321 is cured to keep the first prism 34a and the second prism 35b at the relative position determined by calibration to form a light turning element 30.

[0079] In another embodiment of the present application, a first adhesive medium 321 is firstly arranged between the first bonding surface 304 and the second bonding surface 305 where the first prism 34a and the second prism 35a are bonded to each other, and the first prism 34a and the second prism 35a are pre-fixed by the first adhesive medium 321; then, the relative position of the first prism 34a and the second prism 35a is adjusted so that the first prism 34a and the second prism 35a are aligned; finally, the first adhesive medium 321 is cured to keep at least two prisms at the relative position determined by calibration to form a light turning element 30.

[0080] In step S14, a first adhesive medium 321 is disposed between the first light emitting surface 344a of the first prism 34a and the second light incident surface 351a of the second prism 35a to bond the first prism 34a and the second prism 35a together. The first adhesive medium 321 may be first disposed on the first light emitting surface 344a of the first prism 34a, and then the second light incident surface 351a of the second prism 35a is attached to the first adhesive medium 321. Of course, the first adhesive medium 321 may also be first disposed on the second light incident surface 351a of the second prism 35a, and then the first light emitting surface 344a of the first prism 34a is attached to the first adhesive medium 321.

[0081] The first adhesive medium 321 can cover the entire first light emitting surface 344a and the second light incident surface 351a, so that the first light emitting surface 344a or the second light incident surface 351a with the first adhesive medium 321 can still maintain a relatively flat plane, and when the first light emitting surface 344a and the second light emitting surface 354a are bonded to each other, the first adhesive medium 321 can be prevented from being squeezed and bubbles can be generated. If bubbles are generated in the first adhesive medium 321, it will affect the optical path of the light, and new stray light will be generated to affect the imaging effect. Of course, in other embodiments of the present application, the first adhesive medium 321 can also only cover a portion of the first light emitting surface 344a and the second light incident surface 351a to prevent the first adhesive medium 321 from overflowing and causing the surface of the prism to be dirty.

[0082] In one embodiment of the present application, the thickness of the first adhesive medium 321 is 5-10 um. The first adhesive medium 321 can be thermosetting glue, UV glue, UV thermosetting glue or glue of other materials.

[0083] In one embodiment of the present application, continue to refer to Figure 4 , the first adhesive medium 321 and the first light shielding film 311 are disposed together on the bonding surface of the same prism, and the first adhesive medium 321 covers the first light shielding film 311. For example, the first adhesive medium 321 and the first light shielding film 311 are both disposed on the first bonding surface 304 of the first prism 34a or the second bonding surface 305 of the second prism 35a. Wherein, when the first light shielding film 311 is disposed on the first light emitting surface 344a of the first prism 34a, when the first adhesive medium 321 is disposed, the first adhesive medium 321 is also disposed on the first light emitting surface 344a of the first prism 34a, and the first adhesive medium 321 covers the first light shielding film 311. It should be understood that the first light-shielding film 311 protrudes beyond the plane where the first light-emitting surface 344a is located, and the first adhesive medium 321 can not only fill the portion of the first light-emitting surface 344a where the first light-shielding film 311 is not set, but also enable the first light-emitting surface 344a with the first adhesive medium 321 to still maintain a relatively flat plane, and when the first light-emitting surface 344a and the second light-emitting surface 354a are bonded to each other, the first adhesive medium 321 can be prevented from being squeezed to generate bubbles.

[0084] Of course, in another embodiment of the present application, the first adhesive medium 321 and the first light shielding film 311 can also be respectively disposed on the bonding surfaces of different prisms. For example, the first adhesive medium 321 is disposed on the first light emitting surface 344a of the first prism 34a, and the first light shielding film 311 is disposed on the second light incident surface 351a of the second prism 35a.

[0085] In one embodiment of the present application, the light deflection element 30 includes three prisms. Fig.10 As shown, the manufacturing process of the light deflection element 30 includes the following steps:

[0086] S21: Provide a first prism 34b, a second prism 35b and a third prism 36b, wherein the first prism 34b and the second prism 35b have a first gluing surface 304 and a second gluing surface 305 for gluing to each other, and the second prism 35b and the third prism 36b have a third gluing surface 306 and a fourth gluing surface 307 for gluing to each other.

[0087] S22 : providing a first light shielding film 311 and a second light shielding film 312 , disposing the first light shielding film 311 on the first gluing surface 304 or the second gluing surface 305 , and disposing the second light shielding film 312 on the third gluing surface 306 or the fourth gluing surface 307 .

[0088] S23: Using the first prism 34b as a reference, calibrate the relative position of the second prism 35b.

[0089] S24: A first adhesive medium 321 is disposed between the first bonding surface 304 and the second bonding surface 305 to bond the first prism 34b and the second prism 35b together through the first adhesive medium 321, and the first adhesive medium 321 is cured to keep the first prism 34b and the second prism 35b at the calibrated determined position to form a prism semi-finished product.

[0090] S25: Using the semi-finished prism as a reference, calibrate the relative position of the third prism 36b.

[0091] S26: A second adhesive medium 322 is set between the third bonding surface 306 and the fourth bonding surface 307 to bond the third prism 36 b and the prism semi-finished product together through the second adhesive medium 322, and the second adhesive medium 322 is cured to keep the prism semi-finished product and the third prism 36 b at the position determined by calibration to form the light turning element 30.

[0092] It should be understood that steps S21 to S26 in the present application do not represent a sequential relationship, but only represent that the manufacturing process of the light deflection element 30 includes the above steps. For example, step S23 can be before step S24 or after step S24. Step S25 can be before step S26 or after step S26.

[0093] In step S21, Figures 6 to 8 As shown, at least two prisms include a first prism 34b, a second prism 35b and a third prism 36b, the second prism 35b is located between the first prism 34b and the third prism 36b, and the first prism 34b and the third prism 36b are prisms with asymmetric structures. The first prism 34b, the second prism 35b and the third prism 36b are combined together to form a light deflection element 30. Among them, the first prism 34b is implemented as a first trapezoidal prism, the second prism 35b is implemented as a rectangular prism, and the third prism 36b is implemented as a second trapezoidal prism. In the cross section of the light deflection element 30, the first prism 34b and the third prism 36b are asymmetric about the midline O of the lower surface 303 of the light deflection element 30.

[0094] Specifically, the first prism 34b includes a first light incident surface 341b, a first light emitting surface 344b, a first surface 343b and a first reflecting surface 342b, wherein the first light incident surface 341b, the first light emitting surface 344b, the first surface 343b and the first reflecting surface 342b are sequentially connected to form a trapezoidal structure, the first light incident surface 341b and the first surface 343b are parallel to each other, the first reflecting surface 342b is connected between the first light incident surface 341b and the first surface 343b, and the first light emitting surface 344b is connected between the first light incident surface 341b and the first surface 343b. The first light emitting surface 344b is a first bonding surface 304 for bonding the first prism 34b and the second prism 35b to each other. It should be understood that, as mentioned above, in order to reduce the possibility of the first prism 34b being broken, the angle between the first light incident surface 341b and the first reflection surface 342b can be removed so that the first light incident surface 341b and the first reflection surface 342b are connected by a plane or an arc surface.

[0095] The second prism 35b includes a second light incident surface 351b, a second reflection surface 353b, a second light emitting surface 354b, and a second surface 352b, wherein the second light incident surface 351b, the second reflection surface 353b, the second light emitting surface 354b, and the second surface 352b are sequentially connected to form a rectangular structure, the second light incident surface 351b and the second light emitting surface 354b are parallel to each other, and the second reflection surface 353b and the second surface 352b are parallel to each other. The second light incident surface 351b of the second prism 35b is a second bonding surface 305 for bonding the first prism 34b and the second prism 35b, and the second light emitting surface 354b of the second prism 35b is a third bonding surface 306 for bonding the second prism 35b and the third prism 36b.

[0096] The third prism 36b includes a third light incident surface 361b, a third surface 362b, a third reflection surface 363b and a third light emitting surface 364b, wherein the third light incident surface 361b, the third surface 362b, the third reflection surface 363b and the third light emitting surface 364b are sequentially connected to form a trapezoidal structure, the third light emitting surface 364b and the third surface 362b are parallel to each other, the third reflection surface 363b is connected between the third light emitting surface 364b and the third surface 362b, and the third light incident surface 361b is connected between the third light emitting surface 364b and the third surface 362b. The third light incident surface 361b of the third prism 36b is a fourth bonding surface 307 for bonding the second prism 35b and the third prism 36b to each other. It should be understood that, as mentioned above, in order to reduce the possibility of the third prism 36b breaking, the angle between the third light emitting surface 364b and the third reflecting surface 363b can be removed so that the third light emitting surface 364b and the third reflecting surface 363b are connected by a plane or an arc surface.

[0097] When the first prism 34b, the second prism 35b and the third prism 36b are combined to form a light deflection element 30, the first light incident surface 341b of the first prism 34b, the second reflection surface 353b of the second prism 35b and the third light emitting surface 364b of the third prism 36b constitute the upper surface 301 of the light deflection element 30, wherein the first light incident surface 341b is the light incident area 3011 of the upper surface 301 of the light deflection element 30, the second reflection surface 353b is the reflection area 3012 of the upper surface 301 of the light deflection element 30, and the third light emitting surface 364b is the light emitting area 3013 of the upper surface 301 of the light deflection element 30. The first reflection surface 342b of the first prism 34b and the third reflection surface 363b of the third prism 36b constitute the two side surfaces 302 of the light deflection element 30. The first surface 343b of the first prism 34b, the second surface 352b of the second prism 35b and the third surface 362b of the third prism 36b form the lower surface 303 of the light deflection element 30. The first light emitting surface 344b of the first prism 34b corresponds to the second light incident surface 351b of the second prism 35b and are bonded and fixed together by the first adhesive medium 321, and the second light emitting surface 354b of the second prism 35b corresponds to the third light incident surface 361b of the third prism 36b and are bonded and fixed together by the second adhesive medium 322.

[0098] Furthermore, the first light-emitting surface 344b of the first prism 34b is the same size as the second light-entering surface 351b of the second prism 35b, and the second light-emitting surface 354b of the second prism 35b is the same size as the third light-entering surface 361b, so that the first light-emitting surface 344b and the second light-entering surface 351b are more consistent when they are attached, and the second light-emitting surface 354b and the third light-entering surface 361b are more consistent when they are attached. Of course, when the second prism 35b is implemented as a rectangular prism, the second light-entering surface 351b is the same size as the second light-emitting surface 354b, and the first light-emitting surface 344b and the third light-entering surface 361b are the same size.

[0099] In one embodiment of the present application, the length of the first surface 343b of the first prism 34b is different from the length of the third surface 362b of the third prism 36b. Further, the length of the first surface 343b of the first prism 34b, the length of the second surface 352b of the second prism 35b, and the length of the third surface 362b of the third prism 36b are all different.

[0100] In step S22, the light shielding film 31 includes a first light shielding film 311 and a second light shielding film 312. The first light shielding film 311 is disposed on the first bonding surface 304 or the second bonding surface 305 between the first prism 34b and the second prism 35b, and the second light shielding film 312 is disposed on the third bonding surface 306 or the fourth bonding surface 307 between the second prism 35b and the third prism 36b. In this way, the setting process of the light shielding film 31 is simpler, and the thickness of the light shielding film 31 is more controllable, which can avoid the situation where the effective light is blocked due to the large thickness of the light shielding film 31.

[0101] In one embodiment of the present application, the first light shielding film 311 and the second light shielding film 312 have a relatively thin thickness. It should be understood that the light shielding film 31 is arranged to protrude from the surface of the prism. When the light shielding film 31 is thick, on the one hand, it will block the light of the effective light path. On the other hand, when the two prisms are bonded to each other, the bonding medium will be squeezed near the light shielding film 31, which will increase the possibility of bubbles. The bubbles will affect the light path of the light and will generate new stray light to affect the imaging effect. In the present application, the light shielding film 31 can be formed by a deposition etching process, or by a silk screen printing process, so that the thickness of the light shielding film 31 is relatively thin.

[0102] In one embodiment of the present application, the first shading film 311 and the second shading film 312 are arranged parallel to each other so that the first shading film 311 and the second shading film 312 can absorb stray light from the first reflective surface 342b and the third reflective surface 363b, thereby reducing the generation of glare and avoiding affecting the imaging effect.

[0103] In one embodiment of the present application, reference Figure 6 , the first light shielding film 311 and the second light shielding film 312 are arranged on the same prism. For example, the first light shielding film 311 is arranged on the second light incident surface 351b of the second prism 35b, and the second light shielding film 312 is arranged on the second light emitting surface 354b of the second prism 35b. In this way, there is no need to replace the prism during the manufacturing process of the first light shielding film 311 and the second light shielding film 312, which can improve production efficiency.

[0104] In another embodiment of the present application, reference Fig. 7A and Figure 7B The first light shielding film 311 and the second light shielding film 312 may also be disposed on different prisms. For example, the first light shielding film 311 is disposed on the first light emitting surface 344b of the first prism 34b, and the second light shielding film 312 is disposed on the third light incident surface 361b of the third prism 36b. In this way, the flipping of the prisms can be reduced during the manufacturing process of the first light shielding film 311 and the second light shielding film 312, and the production efficiency can be improved.

[0105] In one embodiment of the present application, the first light shielding film 311 and the second light shielding film 312 are in a "U"-shaped structure with an opening, and the opening directions of the first light shielding film 311 and the second light shielding film 312 are the same. For example, the first light shielding film 311 is disposed on the second light surface of the second prism 35b, and the first light shielding film 311 extends from the side where the second surface 352b is located along the height direction toward the side where the second reflection surface 353b is located, and the first light shielding film 311 is in a "U"-shaped structure with an opening, and the direction of the opening is toward the side where the second reflection surface 353b is located. The second light shielding film 312 is disposed on the second light-emitting surface 354b of the second prism 35b, and the second light shielding film 312 extends from the side where the second surface 352b is located along the height direction toward the side where the second reflection surface 353b is located, and the second light shielding film 312 is in a "U"-shaped structure with an opening, and the direction of the opening is toward the side where the second reflection surface 353b is located.

[0106] In another embodiment of the present application, the first light shielding film 311 is disposed on the first light emitting surface 344b of the first prism 34b, and the first light shielding film 311 extends from the side where the first surface 343b is located along the height direction toward the side where the first light incident surface 341b is located, and the first light shielding film 311 is a "U"-shaped structure with an opening, and the direction of the opening is toward the side where the first light incident surface 341b is located. The second light shielding film 312 is disposed on the third light incident surface 361b of the third prism 36b, and the second light shielding film 312 extends from the side where the third surface 362b is located along the height direction toward the side where the third light emitting surface 364b is located, and the second light shielding film 312 is a "U"-shaped structure with an opening, and the direction of the opening is toward the side where the third light emitting surface 364b is located. As can be seen from the foregoing, the optical lens 10 and the photosensitive chip 20 are arranged on the same side of the light deflection element 30, that is, the light enters or exits on the same side of the light deflection element 30, which makes the light path of the light in the light deflection element 30 asymmetric. Therefore, the light path of the stray light in the light deflection element 30 is also asymmetric. Figure 2 In order to fully shield the light path of stray light as much as possible, the first light shielding film 311 and the second light shielding film 312 are not symmetrically arranged relative to the center line O of the lower surface 303 of the light deflection element 30 in the light deflection element 30 .

[0107] Moreover, since the position of the first light shielding film 311 is related to the position of the first bonding surface 304 of the first prism 34b and the second bonding surface 305 of the second prism 35b, and the position of the second light shielding film 312 is related to the position of the third bonding surface 306 of the second prism 35b and the fourth bonding surface 307 of the third prism 36b, when the first prism 34b and the third prism 36b are asymmetrical structures, it is easier to make the first light shielding film 311 and the second light shielding film 312 asymmetrical in the light deflection element 30 relative to the center line O of the lower surface 303 of the light deflection element 30.

[0108] Specifically, continue to refer to Figure 8 When the first prism 34b, the second prism 35b and the third prism 36b are combined into the light deflection element 30, the first light shielding film 311 and the second light shielding film 312 can be arranged adjacent to each other in the light deflection element 30 to block stray light propagating in an asymmetric light path in the light deflection element 30. The distance between the first light shielding film 311 and the second light shielding film 312 ranges from 1.4 mm to 1.8 mm. In a specific example of the present application, the distance between the first light shielding film 311 and the second light shielding film 312 is 1.597 mm.

[0109] In a specific example of the present application, the first light shielding film 311 and the second light shielding film 312 are located on the same side of the center line O of the lower surface 303 of the light deflection element 30, and the distance between the first light shielding film 311 and the center line O of the lower surface 303 is less than the distance between the second light shielding film 312 and the center line O of the lower surface 303. For example, the distance between the first light shielding film 311 and the center line O of the lower surface 303 ranges from 0.04 mm to 0.1 mm, and the distance between the second light shielding film 312 and the center line O of the lower surface 303 ranges from 1.4 mm to 2 mm. In a specific example of the present application, the distance between the first light shielding film 311 and the center line O of the lower surface 303 is 0.056 mm, and the distance between the second light shielding film 312 and the center line O of the lower surface 303 is 1.65 mm.

[0110] Specifically, when the first prism 34b, the second prism 35b and the third prism 36b are combined into the light deflection element 30, the first light shielding film 311 and the second light shielding film 312 extend from one side of the light deflection element 30 toward the opposite side of the light deflection element 30. That is, the first light shielding film 311 and the second light shielding film 312 both extend from the lower surface 303 of the light deflection element 30 toward the upper surface 301 along the height direction, and the opening directions of the first light shielding film 311 and the second light shielding film 312 are the same. The first light shielding film 311 and the second light shielding film 312 have different heights to block stray light propagating in the light deflection element 30 in an asymmetric optical path. In one embodiment of the present application, the height of the first light shielding film 311 is greater than the height of the second light shielding film 312. For example, the height of the first light shielding film 311 ranges from 1.908 mm to 2.371 mm, and the height of the second light shielding film 312 ranges from 0.98 mm to 1.65 mm. In a specific example of the present application, the height of the first light shielding film 311 is 1.98 mm, and the height of the second light shielding film 312 is 1.45 mm, so that the first light shielding film 311 and the second light shielding film 312 cooperate with each other to block the light path of stray light with different propagation angles and directions, so as to block and absorb stray light without affecting the propagation of normal light.

[0111] In one embodiment of the present application, the ratio of the height of the first light shielding film 311 to the height of the light deflection element 30 is in the range of 0.4726 to 0.6300. It should be understood that 0.4726 to 0.6300 includes the end values ​​0.4726 and 0.6300. In a specific example of the present application, the height of the first light shielding film is 1.98 mm, the height of the light deflection element is 4.1 mm, and the ratio of the height of the first light shielding film 311 to the height of the light deflection element 30 is 0.4829.

[0112] In the present application, when the first light shielding film 311 is a "U"-shaped structure with an opening, the first light shielding film 311 has a structure located at the side of the opening and a structure located at the bottom of the opening. The height of the first light shielding film 311 described in the present application refers to the height of the structure located at the bottom of the opening.

[0113] Furthermore, in this embodiment, a certain height margin is also provided for the first light shielding film 311, so that when the light path of the stray light reaches the limit, the first light shielding film 311 can still block the light path of the stray light. In a specific embodiment of the present application, the height range of the first light shielding film 311 is: 1.908mm to 2.371mm, wherein the height margin of the first light shielding film 311 is 0.463mm. It should be understood that 1.908mm to 2.371mm includes the end values ​​1.908mm and 2.371mm.

[0114] In step S23, if Fig.11 As shown, a jig 40 is further provided, the jig 40 includes a slot with an inclined surface, and the first prism 34b is placed in the slot of the jig 40 at an angle such that the first light-emitting surface 344b of the first prism 34b faces upward, and the first reflection surface 342b of the first prism 34b is supported on the inclined surface of the slot. In this way, the first light-emitting surface 344b of the first prism 34b is exposed outside the slot of the jig 40, so that the first light-emitting surface 344b serves as the first gluing surface 304 of the first prism 34b.

[0115] The second prism 35b is clamped at an angle such that the second light emitting surface 354b of the second prism 35b faces upward and the second light incident surface 351b faces downward, and the second prism 35b is moved above the first prism 34b. The second prism 35b can be clamped using a nozzle solution or a clamping claw solution, and during the clamping process, the nozzle or the clamping claw contacts a position of the second prism 35b that does not conduct light, so as to avoid affecting the surface shape of the second prism 35b, thereby affecting the propagation path of the light.

[0116] The gripper or nozzle is controlled to align the center of the second light incident surface 351b of the second prism 35b with the center of the first light emitting surface 344b of the first prism 34b, based on the plane where the first light emitting surface 344b of the first prism 34b is located. In one embodiment of the present application, the accuracy range of the center alignment of the first light emitting surface 344b and the second light incident surface 351b is ±25um.

[0117] The gripper or nozzle is controlled to adjust the inclination of the second light incident surface 351b of the second prism 35b relative to the first light incident surface 344b, based on the plane where the first light emitting surface 344b of the first prism 34b is located, so that the second light incident surface 351b and the first light emitting surface 344b are as parallel to each other as possible. In one embodiment of the present application, the accuracy range of the inclination of the first light emitting surface 344b and the second light incident surface 351b is less than 5um.

[0118] The gripper or nozzle is controlled to adjust the rotation degree of the second light incident surface 351b of the second prism 35b relative to the first light incident surface 344b, based on the plane where the first light emitting surface 344b of the first prism 34b is located, so that each corner and each side of the second light incident surface 351b is aligned with each corner and each side of the first light emitting surface 344b. In one embodiment of the present application, the accuracy range of the rotation degree of the first light emitting surface 344b and the second light incident surface 351b is ±25um.

[0119] It should be understood that the above-mentioned accuracy range can also be referred to as an assembly tolerance range of the first prism 34b and the second prism 35b that can be accepted by the optical system.

[0120] In one embodiment of the present application, step S24 may be implemented before step S23, or after step S23. That is, the relative position of the second prism 35b may be adjusted based on the first prism 34b so that the first prism 34b and the second prism 35b are aligned; then the first adhesive medium 321 is provided on the first bonding surface 304 or the second bonding surface 305; then the first prism 34b and the second prism 35b are bonded together by the first adhesive medium 321; finally, the first adhesive medium 321 is cured to keep the first prism 34b and the second prism 35b at the positions determined by calibration to form a prism semi-finished product.

[0121] In another embodiment of the present application, the first adhesive medium 321 is first set on the first bonding surface 304 or the second bonding surface 305; then the relative position of the second prism 35b is adjusted based on the first prism 34b; then the first prism 34b and the second prism 35b are bonded together through the first adhesive medium 321; finally, the first adhesive medium 321 is cured to keep the first prism 34b and the second prism 35b at the positions determined by calibration to form a prism semi-finished product.

[0122] In another embodiment of the present application, a first adhesive medium 321 is firstly arranged between the first adhesive surface 304 and the second adhesive surface 305, and the first prism 34b and the second prism 35b are pre-fixed by the first adhesive medium 321; then, the position of the second prism 35b is adjusted based on the first prism 34b; finally, the first adhesive medium 321 is cured to keep the first prism 34b and the second prism 35b at the position determined by calibration to form a prism semi-finished product.

[0123] Step S24 may refer to step S14 , wherein the first adhesive medium 321 may be thermosetting glue, UV glue, UV thermosetting glue or glue of other materials.

[0124] It is worth mentioning that, in the process of fixing and connecting the first prism 34b and the second prism 35b by the first adhesive medium 321, bubbles should be avoided in the first adhesive medium 321 to prevent light passing through the bubbles from generating new stray light and affecting the imaging effect.

[0125] In step S25, continue to refer to Fig.11 The third prism 36b is clamped at an angle with the third light incident surface 361b of the third prism 36b facing downward, and the third prism 36b is moved above the prism semi-finished product. The third prism 36b can be clamped using a nozzle solution or a clamping claw solution. During the clamping process, the nozzle or the clamping claw contacts a position of the third prism 36b that does not conduct light, so as to avoid affecting the surface shape of the third prism 36b, thereby affecting the propagation path of the light.

[0126] The clamp or nozzle is controlled to adjust the center of the third light incident surface 361b of the third prism 36b to align with the center of the second light emitting surface 354b based on the plane where the second light emitting surface 354b is located. In one embodiment of the present application, the accuracy range of the center alignment of the second light emitting surface 354b and the third light incident surface 361b is ±25um.

[0127] The clamp or nozzle is controlled to adjust the inclination of the third light incident surface 361b of the third prism 36b relative to the second light incident surface 354b, based on the plane where the second light emitting surface 354b is located, so that the third light incident surface 361b and the second light emitting surface 354b are as parallel to each other as possible. In one embodiment of the present application, the accuracy range of the inclination of the second light emitting surface 354b and the third light incident surface 361b is less than 5um.

[0128] The gripper or nozzle is controlled to adjust the rotation degree of the third light incident surface 361b of the third prism 36b relative to the second light incident surface 354b, based on the plane where the second light incident surface 354b is located, so that each corner and each side of the third light incident surface 361b is aligned with each corner and each side of the second light incident surface 354b. In one embodiment of the present application, the accuracy range of the rotation degree of the second light incident surface 354b and the third light incident surface 361b is ±25um.

[0129] In the present application, the second prism 35b is assembled with the first prism 34b as a reference, so that the second prism 35b and the first prism 34b are aligned with each other. Then, the third prism 36b is assembled with the second prism 35b as a reference, so that the third prism 36b and the second prism 35b are aligned, thereby achieving that the first prism 34b, the second prism 35b and the third prism 36b are all aligned. In this way, the light turning element 30 assembled with the first prism 34b, the second prism 35b and the third prism 36b can have better optical performance in the optical system.

[0130] Of course, if the first prism 34b and the second prism 35b deviate during the alignment process, the third prism 36b can be adjusted so that the light turning element 30 composed of the first prism 34b, the second prism 35b and the third prism 36b has better optical performance in the optical system.

[0131] In one embodiment of the present application, step S26 may be implemented before step S25 or after step S25. That is, the relative position of the third prism 36b may be adjusted based on the semi-finished prism product so that the third prism 36b is aligned with the semi-finished prism product; then the second adhesive medium 322 is disposed on the third bonding surface 306 or the fourth bonding surface 307, and the third prism 36b is bonded to the semi-finished prism product through the second adhesive medium 322; finally, the second adhesive medium 322 is cured to keep the third prism 36b and the semi-finished prism product at the position determined by calibration to form the light deflection element 30.

[0132] In another embodiment of the present application, a second adhesive medium 322 is first set on the third bonding surface 306 or the fourth bonding surface 307; then, the relative position of the third prism 36b is adjusted based on the prism semi-finished product; then, the third prism 36b and the prism semi-finished product are bonded together through the second adhesive medium 322; finally, the second adhesive medium 322 is cured to keep the third prism 36b and the prism semi-finished product at the position determined by calibration to form a light turning element 30.

[0133] In another embodiment of the present application, a second adhesive medium 322 is first set between the third bonding surface 306 and the fourth bonding surface 307, and the third prism 36b and the prism semi-finished product are pre-fixed by the second adhesive medium 322; then, the position of the third prism 36b is adjusted based on the prism semi-finished product; finally, the second adhesive medium 322 is cured to keep the third prism 36b and the prism semi-finished product at the position determined by calibration to form a light turning element 30.

[0134] Step S26 may refer to step S14 , wherein the second adhesive medium 322 may be thermosetting glue, UV glue, UV thermosetting glue or glue of other materials.

[0135] It is worth mentioning that, in the process of fixing and connecting the second prism 35b and the third prism 36b by the second adhesive medium 322, bubbles should be avoided in the second adhesive medium 322 to avoid generating new stray light due to light passing through the bubbles and affecting the imaging effect.

[0136] In one embodiment of the present application, in the process of combining the first prism 34b, the second prism 35b and the third prism 36b into the light deflection element 30, the relative position of the second prism 35b can be adjusted with the first prism 34b as a reference; then, the first adhesive medium 321 is set on the first bonding surface 304, and the first prism 34b and the second prism 35b are bonded together by the first adhesive medium 321; then, the first adhesive medium 321 is cured to keep the first prism 34b and the second prism 35b at the position determined by calibration to form a prism semi-finished product; then, the relative position of the third prism 36b is adjusted with the prism semi-finished product as a reference; then, the second adhesive medium 322 is set on the third bonding surface 306, and the prism semi-finished product and the third prism 36b are bonded together by the second adhesive medium 322; finally, the second adhesive medium 322 is cured to keep the third prism 36b and the prism semi-finished product at the position determined by calibration to form the light deflection element 30.

[0137] In another embodiment of the present application, in the process of combining the first prism 34b, the second prism 35b and the third prism 36b into the light deflection element 30, the first adhesive medium 321 can be first set on the first bonding surface 304; then the relative position of the second prism 35b is adjusted with the first prism 34b as a reference; then the first prism 34b and the second prism 35b are bonded together through the first adhesive medium 321; then the first adhesive medium 321 is cured to keep the first prism 34b and the second prism 35b at the position determined by calibration to form a prism semi-finished product; then the second adhesive medium 322 is set on the third bonding surface 306; then the relative position of the third prism 36b is adjusted with the prism semi-finished product as a reference; then the prism semi-finished product and the third prism 36b are bonded together through the second adhesive medium 322; finally, the second adhesive medium 322 is cured to keep the third prism 36b and the prism semi-finished product at the position determined by calibration to form the light deflection element 30.

[0138] In one embodiment of the present application, a manufacturing process of a split light deflection element 30 is also provided, which includes the following steps:

[0139] S31: Provide a plate-shaped prism blank, and grind the upper and lower surfaces of the prism blank to reduce the roughness of the upper and lower surfaces of the prism blank. The upper surface of the prism blank corresponds to the upper surface 301 of the light deflection element 30, and the lower surface 303 of the prism blank corresponds to the lower surface 303 of the light deflection element 30.

[0140] S32: Using a laser cutting machine, the prism raw material is cut along its length direction to form three semi-finished products of long prism strips.

[0141] S33: Process the surfaces of the semi-finished products of the three long strip prisms by single-sided grinding to process the three long strip prisms into the first long strip prism, the second long strip prism and the third long strip prism. The cross section of the first long strip prism is a first trapezoidal shape, the cross section of the second long strip prism is a rectangular shape, the cross section of the third long strip prism is a second trapezoidal shape, and the first long strip prism and the third long strip prism are asymmetric structures. Among them, the upper surfaces of the first long strip prism, the second long strip prism and the third long strip prism correspond to the upper surface 301 of the light turning element 30, the lower surfaces of the first long strip prism, the second long strip prism and the third long strip prism correspond to the lower surface 303 of the light turning element 30, the inclined side surface of the first long strip prism and the inclined side surface of the third long strip prism correspond to the two side surfaces 302 of the light turning element 30, and the cutting surface of the first long strip prism, the cutting surface of the second long strip prism and the cutting surface of the third long strip prism are later used as the bonding surface for bonding the three prisms to each other.

[0142] Furthermore, in step S33, the edges of the first and third elongated prisms are ground to remove the edges and corners between the upper surface and the inclined side surface of the first and third elongated prisms, so that the upper surface and the inclined side surface are connected by a plane or an arc surface, thereby avoiding the prisms from being easily broken due to the presence of the edges and corners.

[0143] S34: coating the surfaces of the first long prism, the second long prism and the third long prism that need to reflect the light. The upper surface of the first long prism, the inclined side surface of the first long prism, the upper surface of the second long prism, the upper surface of the third long prism and the inclined side surface of the third long prism are coated so that the light can be reflected multiple times on multiple surfaces in the light turning element 30.

[0144] S35: A light shielding film 31 is provided on the bonding surface between the first long prism and the second long prism, and a light shielding film 31 is provided on the bonding surface between the second long prism and the third long prism. In one embodiment of the present application, the light shielding film 31 is provided by a deposition etching process to accurately control the thickness of the light shielding film 31 within 1 μm. In another embodiment of the present application, the light shielding film 31 is provided by ink silk screen printing, but the ink silk screen printing method will cause the thickness of the light shielding film 31 to fluctuate greatly, and there is a risk of bubbles being generated at the bonding position.

[0145] S36: cutting the first long prism, the second long prism and the third long prism in a direction perpendicular to their lengths to form a plurality of block-shaped first prisms 34b, second prisms 35b and third prisms 36b.

[0146] S37: Silk-screen printing is provided on the upper surface of the first prism 34b and the upper surface of the third prism 36b so that effective light can enter the interior of the prism and stray light can be intercepted. It should be understood that the upper surface of the first prism 34b corresponds to the light entrance area 3011 of the upper surface of the light deflection element 30, and the upper surface of the third prism 36b corresponds to the light exit area 3013 of the upper surface of the light deflection element 30. Therefore, silk-screen printing is provided on the upper surface of the first prism 34b and the upper surface of the third prism 36b to better intercept stray light.

[0147] S38: Assemble the first prism 34 b , the second prism 35 b and the third prism 36 b according to the aforementioned steps S11 to S14 or steps S21 to S26 to form the light turning element 30 .

[0148] In another embodiment of the present application, after the above-mentioned step S35, the first long strip prism, the second long strip prism and the third long strip prism are first bonded and fixed according to the above-mentioned steps S11 to S14 or steps S21 to S26 to form a long strip light turning element semi-finished product.

[0149] Then, the strip-shaped light deflection element semi-finished product is cut along a direction perpendicular to its length to form a plurality of block-shaped light deflection elements 30 .

[0150] Finally, a silk screen is provided on the upper surface 301 of the light deflection element 30 so that effective light can enter the interior of the prism and stray light can be intercepted.

[0151] The above describes the basic principles, main features and advantages of the present application. Those skilled in the art should understand that the present application is not limited by the above embodiments, and the above embodiments and the specification only describe the principles of the present application. The present application may have various changes and improvements without departing from the spirit and scope of the present application, and these changes and improvements fall within the scope of the present application for which protection is sought. The scope of protection claimed by the present application is defined by the attached claims and their equivalents.

Claims

1. A telephoto optical system, characterized in that: include: Optical lens; Light turning element, including: A first prism, a second prism and a third prism, wherein the second prism is located between the first prism and the third prism, and the first prism and the third prism are prisms with asymmetric structures; A first light shielding film is disposed between the first prism and the second prism; A second light shielding film is disposed between the second prism and the third prism; The first light shielding film and the second light shielding film extend from one side of the light redirecting element toward the opposite side of the light redirecting element, wherein the first light shielding film and the second light shielding film have different heights; and A photosensitive chip, wherein the light emitted from the optical lens reaches the photosensitive chip after multiple reflections in the light deflection element, and the photosensitive chip and the optical lens are arranged on the same side of the light deflection element.

2. The telephoto optical system according to claim 1, characterized in that: The first light-shielding film and the second light-shielding film are asymmetrically arranged in the light-redirecting element relative to the center line of the lower surface of the light-redirecting element, so that the optical path of the light in the light-redirecting element is asymmetrical.

3. The telephoto optical system according to claim 2, characterized in that: The first prism and the second prism have a first gluing surface and a second gluing surface for gluing to each other, and the second prism and the third prism have a third gluing surface and a fourth gluing surface for gluing to each other; the first shading film is arranged on the first gluing surface or the second gluing surface, and the second shading film is arranged on the third gluing surface or the fourth gluing surface.

4. The telephoto optical system according to claim 3, characterized in that: The first prism includes a first light incident surface, a first light emitting surface, a first surface and a first reflecting surface which are sequentially connected to form a trapezoidal structure; the second prism includes a second light incident surface, a second reflecting surface, a second light emitting surface and a second surface which are sequentially connected to form a rectangular structure; the third prism includes a third light incident surface, a third surface, a third reflecting surface and a third light emitting surface which are sequentially connected to form a trapezoidal structure, wherein the first light emitting surface is the first bonding surface for the first prism and the second prism to be bonded to each other, the second light incident surface is the second bonding surface for the first prism and the second prism to be bonded to each other, the second light emitting surface is the third bonding surface for the second prism and the third prism to be bonded to each other, and the third light incident surface is the fourth bonding surface for the second prism and the third prism to be bonded to each other.

5. The telephoto optical system according to claim 4, characterized in that: The first light incident surface and the first reflection surface are connected via a plane or a curved surface; the third light emitting surface and the third reflection surface are connected via a plane or a curved surface.

6. The telephoto optical system according to any one of claims 1 to 5, characterized in that: The first light shielding film and the second light shielding film are in a "U"-shaped structure with an opening, and the opening directions of the first light shielding film and the second light shielding film are the same.

7. The telephoto optical system according to any one of claims 1 to 5, characterized in that: The first light shielding film and the second light shielding film are arranged parallel to each other in the light deflection element, and the distance between the first light shielding film and the second light shielding film ranges from 1.4 mm to 1.8 mm.

8. The telephoto optical system according to any one of claims 1 to 5, characterized in that: The ratio of the height of the first light shielding film to the height of the light turning element ranges from 0.4726 to 0.6300.

9. The telephoto optical system according to claim 8, wherein: The height of the first light shielding film ranges from 1.908 mm to 2.371 mm, and the height of the second light shielding film ranges from 0.98 mm to 1.65 mm.

10. The telephoto optical system according to any one of claims 1 to 5, characterized in that: The first light shielding film and the second light shielding film are formed by a deposition etching process or a silk screen printing process.

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