Light path extension mechanism, camera module and shooting equipment

Abstract

The utility model discloses a light path extension mechanism, a camera module and shooting equipment, and belongs to the technical field of camera modules. The light path extension mechanism comprises a linear polarizer, a first 1 / 4 wave plate, a semi-transparent and semi-reflective film, an infrared optical filter, a second 1 / 4 wave plate and a reflective polarizer which are arranged in sequence; wherein the light transmission type of the linear polaroid is the same as that of the reflecting and transmitting polaroid; the angle of the first 1 / 4 wave plate and the angle of the second 1 / 4 wave plate are both 45 degrees. According to the optical path extension mechanism, the camera module and the shooting equipment provided by the invention, a long-focal-length functional mechanism can be realized by extending the optical path, and the mechanism is simple, convenient to assemble and low in manufacturing cost.

Description

Technical Field

[0001] The present application belongs to the technical field of camera modules, and in particular, relates to an optical path extension mechanism, a camera module and a shooting device. Background Art

[0002] A telephoto module is provided in the mobile phone camera module to obtain high-quality clear images in long-distance shooting. The telephoto capability of the mobile phone camera module has become one of the essential capabilities of mobile phone photography.

[0003] The mainstream of the existing telephoto solution is the periscope solution. Specifically, a prism and a prism drive motor are set in the camera module to turn the optical path between the lens and the image chip in the camera module to extend the optical path and realize the telephoto function solution. However, the prism itself has large morphological characteristics and spatial volume, and needs to be arranged horizontally, resulting in a large layout space requirement, complex module matching structure, high requirements for lens module assembly and design accuracy, and high cost of prisms and prism drive motors, which are mostly used in mid-to-high-end mobile phones. Summary of the invention

[0004] The present application provides an optical path extension mechanism, a camera module and a shooting device, which are intended to at least to some extent solve the technical problems of large space requirements for the camera module telephoto solution, high assembly and layout precision requirements, and high cost.

[0005] In one aspect of an embodiment of the present application, an optical path extension mechanism is provided, which is applied to a camera module; the optical path extension mechanism comprises: a linear polarizer, a first quarter wave plate, a semi-transparent and semi-reflective film, an infrared filter, a second quarter wave plate, and a reflective polarizer arranged in sequence;

[0006] Wherein, the linear polarizer and the reverse polarizer have the same light transmission type;

[0007] The angles of the first 1 / 4 wave plate and the second 1 / 4 wave plate are both 45 degrees.

[0008] In some embodiments, the semi-transmissive and semi-reflective film is plated on the light incident side of the infrared filter.

[0009] In some embodiments, the first 1 / 4 wave plate is attached to the semi-transparent and semi-reflective film, the linear polarizer is attached to the first 1 / 4 wave plate, and the second 1 / 4 wave plate is attached to the light output side of the infrared filter.

[0010] In some embodiments, the linear polarizer transmits P-polarized light, and the transmissive polarizer reflects S-polarized light and transmits P-polarized light.

[0011] In some embodiments, the linear polarizer, the first quarter wave plate, the semi-transmissive and semi-reflective film, the infrared filter, the second quarter wave plate, and the reflective polarizer are packaged together by a COB mounting process.

[0012] In another aspect of the embodiment of the present application, a camera module is further provided, comprising: a lens, an image chip and the optical path extension mechanism;

[0013] The optical path extension mechanism is arranged between the lens and the image chip, the linear polarizing plate is close to the lens, and the reverse polarizing plate is close to the image chip.

[0014] In some embodiments, the reverse-transmissive polarizer is attached to the light-incoming side of the image chip.

[0015] In some embodiments, the camera module also includes a shell, and the lens, the image chip and the optical path extension mechanism are arranged in the shell.

[0016] In some embodiments, the infrared filter is connected to the housing.

[0017] According to a third aspect of the embodiments of the present application, a shooting device is also provided, including: the above-mentioned camera module.

[0018] In some embodiments, the photographing device is a mobile phone or a tablet computer.

[0019] The embodiments of the present application have at least the following beneficial effects:

[0020] The optical path extension mechanism, camera module and shooting equipment provided in the embodiments of the present application transform the incident light through the optical elements of the linear polarizer, the first 1 / 4 wave plate, the semi-transparent and semi-reflective film, the filter, the second 1 / 4 wave plate and the reflective polarizer arranged in sequence, and can output after multiple reflections between the optical elements, so as to achieve light path folding, thereby extending the optical path to a certain extent, changing the back focus of the telephoto, and thus achieving the telephoto effect. Compared with the high-end periscope solution, the telephoto function is achieved with a low-end module; at the same time, the arrangement of multiple stacked optical lenses makes the assembly difficulty and space requirements smaller, and the cost is relatively lower; on the other hand, the conversion process of natural light through the above-mentioned optical path extension mechanism is: natural light---P polarized light---circularly polarized light---S polarized light---circularly polarized light---P polarized light. After a series of conversions, the purpose of extending the optical path is achieved, and the effect of zooming is achieved. Generally speaking, the purpose of 3 times telephoto can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 A schematic diagram of the principle structure of the optical path extension mechanism in an embodiment of the present application is shown;

[0023] Figure 2 A schematic diagram of the structure of the camera module in an embodiment of the present application is shown.

[0024] Reference numerals:

[0025] 100-optical path extension mechanism, 1-lens, 2-linear polarizer, 3-first 1 / 4 wave plate, 4-semi-transparent and semi-reflective film, 5-infrared filter, 6-second 1 / 4 wave plate, 7-reflective polarizer, 8-image chip, 91-natural light, 92-first P polarized light, 93-first left-handed circularly polarized light, 94-S polarized light, 95-second left-handed circularly polarized light, 96-right-handed circularly polarized light, 97-second P polarized light. DETAILED DESCRIPTION

[0026] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0027] In addition, the present application may repeat reference numbers and / or reference letters in different examples, and such repetition is for the purpose of simplicity and clarity, and does not in itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present application provides various specific examples of processes and materials, but those of ordinary skill in the art may recognize the application of other processes and / or the use of other materials.

[0028] The present application is described below with reference to the accompanying drawings and specific embodiments:

[0029] In the camera module, natural light enters the module from the lens and is then projected onto the image chip to achieve imaging. Considering the distance limitation from the lens to the image chip, the shooting distance is limited. With the emergence of telephoto solutions such as periscope solutions, the shooting range has been greatly extended. The essence of this is to extend the optical path between the lens and the image chip through a prism assembly to change the back focus of the telephoto lens, thereby achieving the purpose of shooting clear images at a long distance.

[0030] Among them, the essence of the periscope solution is to refract and reflect light through prisms and the operation of moving prisms, thereby extending the optical path to a certain extent; however, the spatial form and volume of the prism itself require a large and three-dimensional placement space, and the prism moving mechanism and moving operation also require a certain space, which leads to the overall periscope solution. The space required is very large, and its cost is high, the installation requirements are high, and it is mostly used in high-end terminal products. It has poor adaptability and is difficult to be widely used.

[0031] To this end, an embodiment of the present application provides an optical path extension mechanism 100, which is mainly used in small terminal devices such as mobile phones, taking into account the layout requirements of small space, low cost, and low difficulty, thereby improving its assembly adaptability and expanding the scope of applicable products.

[0032] See also Figure 1 and Figure 2 The optical path extension mechanism 100 provided in the embodiment of the present application is a collection of optical element components, which are assembled as a whole in the camera module, and can be specifically arranged between the lens 1 and the image chip 8, and can realize the conversion, reflection and transmission of incident natural light, thereby realizing the extension of the optical path.

[0033] Specifically, the optical path extension mechanism 100 may include: a linear polarizer 2, a first quarter wave plate 3, a semi-transparent and semi-reflective film 4, an infrared filter 5, a second quarter wave plate 6 and a reverse polarizer 7 arranged in sequence; wherein the natural light 91 is incident from the linear polarizer 2 and emitted from the reverse polarizer 7.

[0034] The linear polarizer 2 and the reverse polarizer 7 have the same light transmission type, that is, the type of light with the same polarization state that can be transmitted is the same. The first quarter wave plate 3 and the second quarter wave plate 6 are both 45 degrees, and are used to convert linear polarization into circular polarization.

[0035] Thereby, the natural light 91 is converted into single polarization light, such as P polarized light, through the linear polarizer 2. For the convenience of description, the following description takes the linear polarizer 2 as a P-type polarizer and outputs P polarized light as an example. Correspondingly, the output light of the reflective polarizer 7 is also P polarized light, and reflects S polarized light.

[0036] Therefore, after the natural light 91 passes through the linear polarizer 2, the first P polarized light 92 is output, and the first P polarized light 92 is converted into a first left-handed circularly polarized light 93 by the first 1 / 4 wave plate 3, and then passes through the semi-transparent and semi-reflective film 4 and the infrared filter 5 from the front; and the first left-handed circularly polarized light 93 is further converted into S polarized light 94 by the second 1 / 4 wave plate 6; because the reverse polarizer 7 transmits P polarized light and reflects S polarized light, the S polarized light 94 cannot pass through the reverse polarizer 7, and will be reflected on the surface of the reverse polarizer 7, and further pass through the second 1 / 4 wave plate 6 and be converted into a second left-handed circularly polarized light 95, and the second left-handed circularly polarized light 95 cannot pass through the semi-reflective and semi-transparent film 4 from the reverse side of the semi-reflective and semi-transparent film 4, and can only be reflected again and converted into right-handed circularly polarized light 96, and then converted into a second P polarized light 97 by the second 1 / 4 wave plate 6 and further pass through the reverse polarizer 7; thereby, the optical path is extended through multiple reflection and conversion.

[0037] On the other hand, the optical path extension mechanism 100 is composed of a plurality of optical lenses or membranes stacked together, so that the overall size and height are smaller than those of the periscope solution, the assembly difficulty is lower, and the overall cost is also lower.

[0038] In some embodiments, the linear polarizer 2, the first quarter wave plate 3, the semi-transparent and semi-reflective film 4, the infrared filter 5, the second quarter wave plate 6 and the reflective polarizer 7 arranged in sequence in the optical path extension mechanism 100 can be formed by a COB mounting process, which can reduce the overall weight and volume to a certain extent, thereby further reducing the volume of the optical path extension mechanism 100.

[0039] In some embodiments, the selection of the linear polarizer 2, the semi-transparent and semi-reflective film 4, and the reverse polarizer 7 can be changed. The reverse polarizer 7 transmits S-polarized light and reflects P-polarized light. The linear polarizer 2 can also be an S-polarizer. After the natural light passes through the linear polarizer 2, S-polarized light is output; accordingly, it is specifically converted into the first right-handed circularly polarized light after passing through the first 1 / 4 wave plate 3, and then passes through the semi-transparent and semi-reflective film 4 and the infrared filter 5 from the front; and the first right-handed circularly polarized light is further converted into P-polarized light through the second 1 / 4 wave plate 6; due to the The reverse polarizer 7 transmits S polarized light and reflects P polarized light. The P polarized light cannot pass through the reverse polarizer 7, and will be reflected on the surface of the reverse polarizer 7, and further pass through the second 1 / 4 wave plate 6 and be converted into a second right-handed circularly polarized light, while the second right-handed circularly polarized light cannot pass through the semi-reflective semi-transparent membrane 4 from the back side of the semi-reflective semi-transparent membrane 4, and can only be reflected again and converted into left-handed circularly polarized light, and then converted into a second S polarized light through the second 1 / 4 wave plate 6 and further pass through the reverse polarizer 7; thereby, the optical path is extended through multiple reflection and conversion.

[0040] In some embodiments, in order to simplify the assembly operation, the semi-transparent and semi-reflective film 4 can also be directly plated on the light-incoming side of the infrared filter 5, so that the assembly of the semi-transparent and semi-reflective film 4 and the infrared filter 5 can be completed during the manufacturing process, simplifying the assembly efficiency and improving the assembly accuracy. This can also reduce the thickness of the overall optical path extension mechanism 100 to a certain extent, making it more suitable for arrangement in a small space and reducing the assembly space requirement.

[0041] In some embodiments, in order to further reduce the overall thickness of the optical path extension mechanism 100, the first 1 / 4 wave plate 3 can also be attached to the semi-transparent and semi-reflective film 4, and the linear polarizer 2 can be attached to the first 1 / 4 wave plate 3, thereby reducing the overall thickness of the light-incoming side of the infrared filter 5, and the second 1 / 4 wave plate 6 can be attached to the light-emitting side of the infrared filter 5, thereby reducing the overall thickness of the light-emitting side of the infrared filter 5.

[0042] On the other hand, this method of attachment and fixing also reduces the difficulty of assembly to a certain extent. At the same time, the lower overall thickness is more suitable for the narrow space between the lens 1 and the image chip 8 of the micro camera module, meeting the installation requirements of most camera modules and terminal products.

[0043] In some embodiments, the optical path extension mechanism 100 can be installed as an assembled molded product as a whole between the lens 1 and the image chip 8, further reducing the difficulty of installation and the requirements for the basic matching mechanism of the module.

[0044] The embodiment of the present application also provides a camera module equipped with the above-mentioned optical path extension mechanism 100, which mainly includes a lens 1 and an image chip 8, wherein the optical path extension mechanism 100 is arranged between the lens 1 and the image chip 8, wherein the linear polarizer 2 is close to the side of the lens 1, and the translucent polarizer 7 is arranged on the side close to the image chip 8, so that the natural light incident from the lens 1 enters the optical path extension mechanism 100 from the linear polarizer 2, is emitted from the translucent polarizer 7, and is projected onto the image chip 8, so as to achieve the purpose of extending the optical path between the lens 1 and the image chip 8. The optical path extension mechanism 100 is arranged in the limited space between the lens 1 and the image chip 8, and a telephoto function mechanism is realized.

[0045] In some embodiments, in order to reduce the influence of the optical path extension mechanism 100 on the overall assembly height of the camera module and maintain the distance between the reverse polarizer 7 and the second 1 / 4 wave plate 6 to maintain a good reflection distance, the reverse polarizer 7 can be directly attached to the light-incoming side of the image chip 8, thereby well coordinating the telephoto function mechanism with the camera module structure.

[0046] In some embodiments, the mounting structure of the infrared filter 5 can be used to support the optical path extension mechanism 100, thereby reducing the impact of installing the optical path extension mechanism 100 on the camera module housing and simplifying the assembly difficulty to a certain extent.

[0047] The embodiment of the present application also provides a camera device equipped with the above-mentioned camera module, so that telephoto shooting can be achieved based on the above-mentioned optical path extension mechanism.

[0048] In some embodiments, the camera device may be a mobile phone, a tablet computer or other terminal products.

[0049] The optical path extension mechanism, camera module and shooting equipment provided in the embodiments of the present application transform the incident light through the optical elements of the linear polarizer, the first 1 / 4 wave plate, the semi-transparent and semi-reflective film, the filter, the second 1 / 4 wave plate and the reflective polarizer arranged in sequence, and can output after multiple reflections between the optical elements, so as to achieve light path folding, thereby extending the optical path to a certain extent, changing the back focus of the telephoto, and thus achieving the telephoto effect. Compared with the high-end periscope solution, the telephoto function is achieved with a low-end module; at the same time, the arrangement of multiple stacked optical lenses makes the assembly difficulty and space requirements smaller, and the cost is relatively lower; on the other hand, the conversion process of natural light through the above-mentioned optical path extension mechanism is: natural light---P polarized light---circularly polarized light---S polarized light---circularly polarized light---P polarized light. After a series of conversions, the purpose of extending the optical path is achieved, and the effect of zooming is achieved. Generally speaking, the purpose of 3 times telephoto can be achieved.

[0050] In the present application, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0051] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise" and "counterclockwise" indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0052] It should be noted that all directional indications in the embodiments of the present application are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0053] In this application, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" 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 or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0054] In addition, the descriptions of "first", "second", etc. in this application are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0055] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine different embodiments or examples described in this specification.

[0056] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0057] Although the embodiments of the present application have been shown and described, those skilled in the art will appreciate that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the claims and their equivalents.

Claims

1. An optical path extension mechanism, applied to a camera module; characterized in that: The optical path extension mechanism comprises: a linear polarizer, a first quarter wave plate, a semi-transparent and semi-reflective film, an infrared filter, a second quarter wave plate and a reflective polarizer which are arranged in sequence; Wherein, the linear polarizer and the reverse polarizer have the same light transmission type; The angles of the first 1 / 4 wave plate and the second 1 / 4 wave plate are both 45 degrees.

2. The optical path extension mechanism according to claim 1, characterized in that: The semi-transmissive and semi-reflective film is plated on the light-incoming side of the infrared filter.

3. The optical path extension mechanism according to claim 1, characterized in that: The first 1 / 4 wave plate is attached to the semi-transparent and semi-reflective film, the linear polarizer is attached to the first 1 / 4 wave plate, and the second 1 / 4 wave plate is attached to the light-emitting side of the infrared filter.

4. The optical path extension mechanism according to claim 1, characterized in that: The linear polarizer transmits P polarized light, and the transverse polarizer reflects S polarized light and transmits P polarized light.

5. The optical path extension mechanism according to claim 1, characterized in that: The linear polarizer, the first quarter wave plate, the semi-transparent and semi-reflective film, the infrared filter, the second quarter wave plate and the reflective polarizer are packaged as one by one using a COB mounting process.

6. A camera module, characterized in that: include: A lens, an image chip, and an optical path extension mechanism as claimed in any one of claims 1 to 5; The optical path extension mechanism is arranged between the lens and the image chip, the linear polarizing plate is close to the lens, and the reverse polarizing plate is close to the image chip.

7. The camera module according to claim 6, characterized in that: The reverse polarizing plate is attached to the light incident side of the image chip.

8. The camera module according to claim 7, characterized in that: The camera module also includes a shell, and the lens, the image chip and the optical path extension mechanism are arranged in the shell.

9. The camera module according to claim 8, characterized in that: The infrared filter is connected to the housing.

10. A photographing device, characterized in that: include: A camera module as described in any one of claims 6 to 9.

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