CN211505999U

CN211505999U - Imaging lens and electronic apparatus

Info

Publication number: CN211505999U
Application number: CN201922203589.6U
Authority: CN
Inventors: 张倩; 陈杭; 胡增新
Original assignee: Sunny Optical Zhejiang Research Institute Co Ltd
Current assignee: Sunny Optical Zhejiang Research Institute Co Ltd
Priority date: 2019-12-10
Filing date: 2019-12-10
Publication date: 2020-09-15
Anticipated expiration: 2029-12-10

Abstract

An imaging lens and an electronic apparatus. The imaging lens includes: a partial reflection element for reflecting a part of the image light and transmitting another part of the image light; a polarization reflection and transmission element for transmitting the image light with the first polarization state and reflecting the image light with the second polarization state; a first 1/4 wave plate, wherein the first 1/4 wave plate is correspondingly disposed between the partially reflective transmissive element and the polarization reflective element for transforming image light having first and second polarization states and image light having a circular polarization state to each other; and a lens group, wherein at least one lens in the lens group is correspondingly arranged between the partial reflecting element and the polarization reflecting element and is used for converging and/or diverging the image light transmitted between the partial reflecting element and the polarization reflecting element for multiple times.

Description

Imaging lens and electronic apparatus

Technical Field

The present invention relates to the field of optical lenses, and more particularly, to an imaging lens and an electronic device.

Background

In recent years, with the continuous development of scientific technology, more and more electronic devices with display functions are widely applied to daily life and work of people, and have a great market and development prospect. The imaging lens is an indispensable core component of an electronic device having a display function, and directly affects the quality of an image displayed by the electronic device.

Currently, as shown in fig. 1, the conventional imaging lens 1P generally includes a lens group 11P, wherein the lens group 11P is disposed at an output side of the image source 2P for imaging an image outputted from the image source 2P with a certain magnification.

However, when the required magnification is larger, the number of lenses in the lens group 11P of the conventional imaging lens 1P is generally larger, so that the volume and weight of the conventional imaging lens 1P are increased greatly. In addition, when the demand for the angle of view and the like is rapidly increased, the number of lenses required for the conventional imaging lens 1P is also significantly increased, which inevitably increases the volume of the lens, and particularly makes it more difficult to reduce the size in the longitudinal direction of the lens. On the other hand, if the size of the conventional imaging lens 1P is limited, the optical length in the conventional imaging lens 1P becomes ultra short. In order to achieve a large field angle, the angle of light passing through the lens is inevitably large, so that the sensitivity of the lens in the lens group 11P of the conventional imaging lens 1P is increased, which is not favorable for assembling the lens.

Disclosure of Invention

An advantage of the present invention is to provide an imaging lens and an electronic apparatus that can fold an imaging optical path, contributing to reduction in overall volume and weight.

Another advantage of the present invention is to provide an imaging lens and an electronic apparatus, wherein in an embodiment of the present invention, the imaging lens can selectively multiplex lenses in a lens group to reduce the number of required lenses, thereby greatly reducing the volume and weight of the imaging lens and reducing the cost.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein the imaging lens can be well adapted to the market demand for small-sized, light-weight, high-imaging-quality, low-cost lenses in an embodiment of the present invention.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein in an embodiment of the present invention, the imaging lens can compress and control a chief ray tilt angle (CRA) of the lens well, which helps to better ensure uniformity of picture brightness.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein in an embodiment of the present invention, the imaging lens can provide a long enough imaging optical path in a small enough space to reduce the sensitivity of the lens, which facilitates the assembly of the imaging lens.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein in an embodiment of the present invention, the imaging lens is not only suitable for an electronic device configured with an image source to enable the electronic device to have a display function, but also suitable for an electronic device configured with an image sensor to enable the electronic device to have a camera function.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein in an embodiment of the present invention, the imaging lens can maximally compress its length, so as to make the structure of the imaging lens more compact while reducing the volume.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein in an embodiment of the present invention, the imaging lens can maximally fold an optical path in a limited space while ensuring an imaging optical path, so as to better control a CRA of the imaging lens, so as to ensure better uniformity of brightness of a picture.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein in an embodiment of the present invention, the imaging lens can ensure a sufficient imaging optical path in a limited space without increasing the volume, so that the angle of light reaching the lens is smooth, which is beneficial to reducing the system sensitivity and ensuring a better assembly effect.

Another advantage of the present invention is to provide an imaging lens and an electronic device, wherein in an embodiment of the present invention, the imaging lens can be assembled by a common coating and gluing process, and has better operability.

Another advantage of the present invention is to provide an imaging lens and an electronic apparatus, in which it is not necessary to use expensive materials or complicated structures in order to achieve the above advantages. Therefore, the present invention successfully and effectively provides a solution to not only provide a simple imaging lens and electronic apparatus, but also increase the practicality and reliability of the imaging lens and electronic apparatus.

To achieve at least one of the above advantages or other advantages and objects, the present invention provides an imaging lens for performing imaging processing on image light, wherein the imaging lens includes:

a partial reflection element for reflecting a part of the image light and transmitting another part of the image light;

a polarization reflection and transmission element for transmitting the image light with the first polarization state and reflecting the image light with the second polarization state;

a first 1/4 wave plate, wherein the first 1/4 wave plate is disposed between the partially reflective transmissive element and the polarization reflective element, respectively, for interconverting image light having first and second polarization states with image light having a circular polarization state; and

a set of lenses, wherein at least one lens of the set of lenses is disposed between the partially reflective element and the polarized reflective element, respectively, for converging and/or diverging the image light propagating between the partially reflective element and the polarized reflective element a plurality of times.

In an embodiment of the invention, all the lenses of the lens group are disposed between the partial transflective element and the polarization transflective element.

In an embodiment of the invention, the partially reflective element is a partially reflective film plated on a surface of one of the lenses of the lens group or a light-transmitting substrate plated with a partially reflective film.

In an embodiment of the invention, the polarization reflective and transmissive element is a polarization splitting film or a semi-reflective and semi-transmissive polarizer.

In an embodiment of the invention, the imaging lens further includes a second 1/4 wave plate, wherein the second 1/4 wave plate is correspondingly disposed outside the partially reflective element, and the partially reflective element is located between the second 1/4 wave plate and the first 1/4 wave plate, wherein the second 1/4 wave plate is configured to convert the image light having the first and second polarization states and the image light having the circular polarization state into each other.

In an embodiment of the present invention, the imaging lens further includes a polarizer, wherein the polarizer is correspondingly disposed outside the second 1/4 wave plate, and the second 1/4 wave plate is located between the polarizer and the partially reflective-transmissive element, wherein the polarizer is configured to convert the image light having the non-polarized state into the image light having the first polarized state.

In an embodiment of the present invention, the polarizing element is a polarizer or a polarization splitter.

In an embodiment of the invention, the imaging lens further includes a parasitic light filtering element, wherein the parasitic light filtering element is correspondingly disposed outside the polarization element, and the polarization element is located between the parasitic light filtering element and the second 1/4 wave plate, wherein the parasitic light filtering element is configured to filter parasitic light in the image light.

In an embodiment of the present invention, the parasitic light filtering element is an 1/4 wave plate having an angle of 45 degrees.

According to another aspect of the present invention, the present invention further provides an electronic device comprising:

at least one image source for outputting image light;

at least one near-eye display device, wherein the near-eye display device is used for displaying an image corresponding to the image light; and

the imaging lens is correspondingly arranged on a light path between the image source and the near-eye display device and is used for carrying out imaging processing on the image light from the image source and transmitting the image light after the imaging processing to the near-eye display device; wherein the imaging lens includes:

a partially reflective element, wherein the partially reflective element is adjacent to the image source, for reflecting a portion of the image light and transmitting another portion of the image light;

a polarizing reflective element, wherein the polarizing reflective element is remote from the image source, and is configured to transmit image light having a first polarization state and reflect image light having a second polarization state;

at least one photosensitive sensor, wherein the photosensitive sensor is provided with a photosensitive path; and

at least one imaging lens, wherein the imaging lens is correspondingly arranged on the photosensitive path of the photosensitive sensor and is used for carrying out imaging processing on the image light propagating along the photosensitive path, so that the photosensitive sensor receives the image light processed by the imaging lens for imaging; wherein the imaging lens includes:

Further objects and advantages of the invention will be fully apparent from the ensuing description and drawings.

These and other objects, features and advantages of the present invention will become more fully apparent from the following detailed description, the accompanying drawings and the claims.

Drawings

Fig. 1 shows a schematic structural diagram of a conventional imaging lens.

Fig. 2 is a schematic structural diagram of an imaging lens according to an embodiment of the invention.

Fig. 3 shows an application example of the imaging lens according to the above-described embodiment of the present invention.

Fig. 4 shows another application example of the imaging lens according to the above-described embodiment of the present invention.

Fig. 5 shows a first modified implementation of the imaging lens according to the above-described embodiment of the present invention.

Fig. 6 shows a second modified implementation of the imaging lens according to the above-described embodiment of the present invention.

Fig. 7 shows a third modified implementation of the imaging lens according to the above-described embodiment of the invention.

Fig. 8 shows a fourth modified implementation of the imaging lens according to the above-described embodiment of the present invention.

FIG. 9 shows a schematic diagram of an electronic device according to an embodiment of the invention.

FIG. 10 shows a schematic diagram of an electronic device according to another embodiment of the invention.

Detailed Description

The following description is presented to disclose the invention so as to enable any person skilled in the art to practice the invention. The preferred embodiments in the following description are given by way of example only, and other obvious variations will occur to those skilled in the art. The basic principles of the invention, as defined in the following description, may be applied to other embodiments, variations, modifications, equivalents, and other technical solutions without departing from the spirit and scope of the invention.

It will be understood by those skilled in the art that in the present disclosure, the terms "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in an orientation or positional relationship indicated in the drawings for ease of description and simplicity of description, and do not indicate or imply that the referenced devices or components must be constructed and operated in a particular orientation and thus are not to be considered limiting.

In the present invention, the terms "a" and "an" in the claims and the description should be understood as meaning "one or more", that is, one element may be one in number in one embodiment, and the element may be more than one in number in another embodiment. The terms "a" and "an" should not be construed as limiting the number unless the number of such elements is explicitly recited as one in the present disclosure, but rather the terms "a" and "an" should not be construed as being limited to only one of the number.

In the description of the present invention, it is to be understood that the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, it should be noted that, unless explicitly stated or limited otherwise, the terms "connected" and "connected" are to be interpreted broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Referring to fig. 2 to 4 of the drawings, an imaging lens according to an embodiment of the present invention is illustrated, wherein the imaging lens 1 is used for performing an imaging process on image light to assist in achieving a display or image pickup effect. Specifically, as shown in fig. 2 to 4, the imaging lens 1 includes a partial transflective element 10, a polarization transflective element 20, a first 1/4 wave plate 30, and a lens group 40. The partially reflective element 10 is configured to reflect a portion of the image light and transmit another portion of the image light. The polarization reflective and transmissive element 20 is configured to reflect image light 101 having a first polarization state and transmit image light 102 having a second polarization state. The first 1/4 wave plate 30 is disposed between the partially reflective transmissive element 10 and the polarization reflective transmissive element 20, respectively, wherein the first 1/4 wave plate 30 is configured to convert the

image light

101, 102 having the first or second polarization state into image light 103 having a circular polarization state, and the first 1/4 wave plate 30 is further configured to convert the image light 103 having the circular polarization state into the

image light

102, 101 having the second or first polarization state; that is, the first 1/4 wave plate 30 is used to convert the

image light

101, 102 with the first or second polarization state and the image light 103 with the circular polarization state into each other. At least one lens 41 of the lens group 40 is disposed between the partial reflective element 10 and the polarization reflective element 20, and is used for converging and/or diverging various image lights propagating between the partial reflective element 10 and the polarization reflective element 20 for multiple times. It is to be understood that the optical axis of the imaging lens 1 of the present invention is indicated by a dotted line in fig. 2; while the optical path in the imaging lens 1 is indicated by a dashed line in fig. 2.

It is noted that, in the above-mentioned embodiment of the present invention, the image light 101 having the first polarization state may be, but is not limited to, implemented as image light having a P polarization state (P polarization image light for short); accordingly, the image light 102 having the second polarization state may be, but is not limited to, implemented as image light having an S polarization state (S polarization image light for short). Of course, in other examples of the present invention, the polarization direction of the image light 101 having the first polarization state and the polarization direction of the image light 102 having the second polarization state may be perpendicular to each other, and the present invention is not described in detail herein.

More specifically, as shown in fig. 2, the polarization reflective and transmissive element 20 of the imaging lens 1 may be, but is not limited to, implemented as a polarization splitting film 21 (such as a PBS film) for allowing P-polarized image light to transmit and reflecting S-polarized image light. Of course, in other examples of the present invention, the polarization reflective and transmissive element 20 may be implemented as other optical elements such as a transflective polarizer, as long as it can transmit the P-polarized image light and reflect the S-polarized image light.

In addition, as shown in fig. 2, the partially reflective element 10 of the imaging lens 1 may be implemented as a partially reflective film 11, wherein the partially reflective film 11 is plated on a surface of one of the lenses 41 in the lens group 40 to allow a part of the image light to pass through and reflect another part of the image light. For example, the partially reflective and semi-transmissive film 11 may be implemented as a semi-reflective and semi-transmissive film to allow 50% of the image light to pass through and reflect the remaining 50% of the image light. Of course, in other examples of the present invention, the partially reflective element 10 may also be implemented as a light-transmissive substrate plated with a partially reflective film, so that the partially reflective element 10 acts as a separate optical element.

It should be noted that the imaging lens 1 of the present invention can be applied to an electronic device (e.g., a near-eye display device) having an image source 800, so that the imaging lens 1 firstly images image light from the image source 800 and then transmits the image light to the eyes of a user to form an image, so that the electronic device can have a function of displaying a corresponding image; the present invention can also be applied to an electronic device (e.g., a camera module) having a photo sensor 900, so that the imaging lens 1 performs an imaging process on image light, and then transmits the image light after the imaging process to the photo sensor 900 to be received and imaged, so that the electronic device can have a camera function.

Illustratively, as shown in fig. 3, when the imaging lens 1 is applied to an electronic device having an image source 800, and the image source 800 is implemented as a circularly polarized image source 801 for directly outputting the image light 103 having the first circular polarization state, the partial transflective element 10 of the imaging lens 1 is located adjacent to the image source 800, and the polarization transflective element 20 of the imaging lens 1 is located away from the image source 800. The first 1/4 wave plate 30 is stacked on the polarization reflective and transmissive element 20 and is located between the polarization reflective and transmissive element 20 and the partially reflective and transmissive element 10. All of the lenses 41 in the lens set 40 are correspondingly disposed between the partially reflective and transmissive element 10 and the first 1/4 wave plate 30.

Thus, as shown in fig. 3, when the image source 800 outputs the image light 103 with circular polarization, a portion of the image light 103 with circular polarization will first pass through the partially reflective element 10 and then pass through the set of lenses 40 to be converged and/or diverged; then, the image light 103 with circular polarization transmitted through the set of lenses 40 will be converted into the image light 102 with second polarization (e.g., S-polarized image light) by the first 1/4 wave plate 30; thereafter, the image light 102 having the second polarization state will be reflected by the polarization reflective and transmissive element 20 back to the first 1/4 wave plate 30 to be converted by the first 1/4 wave plate 30 into the image light 103 having a circular polarization state; the image light 103 with circular polarization state will then transmit through the set of optics 40 to be converged and/or diverged; finally, a portion of the image light 103 with circular polarization state is reflected by the partially reflective element 10 back to the lens set 40, and after passing through the lens set 40 to be converged and/or diverged, is converted into the image light 101 with first polarization state (e.g. P-polarized image light) by the first 1/4 wave plate 30, so that the image light 101 with first polarization state passes through the polarized reflective element 20 to output the imaging lens 1, and is then imaged in the eye of the user to be viewed by the user as a corresponding image.

Particularly, since all the lenses 41 in the lens group 40 in the imaging lens 1 of the present invention are reasonably multiplexed, the imaging lens 1 of the present invention can maximally fold the imaging optical path in a limited space while ensuring a sufficient optical path, which is helpful for better controlling the lens CRA, and further better ensuring the brightness uniformity of the picture. Of course, in other examples of the present invention, only a portion of the lenses 41 (or none of the lenses 41) in the set 40 are disposed between the partial transflective element 10 and the polarization transflective element 20, and the remaining other lenses 41 (or all of the lenses 41) in the set 40 may be disposed at positions other than between the partial transflective element 10 and the polarization transflective element 20, such that a portion of the lenses 41 (or none of the lenses 41) in the set 40 are multiplexed three times, while the other lenses 41 (or all of the lenses 41) are utilized only once.

Similarly, as shown in fig. 4, when the imaging lens 1 is applied to an electronic device having a photosensor 900, the partial transflective element 10 of the imaging lens 1 is located at a position adjacent to the photosensor 900, and the polarization transflective element 20 of the imaging lens 1 is located at a position distant from the photosensor 900. The first 1/4 wave plate 30 is stacked on the polarization reflective and transmissive element 20 and is located between the polarization reflective and transmissive element 20 and the partially reflective and transmissive element 10. All of the lenses 41 in the lens set 40 are correspondingly disposed between the partially reflective and transmissive element 10 and the first 1/4 wave plate 30.

Thus, as shown in fig. 4, the image light 101 (e.g., P-polarized image light) with the first polarization state in the image light (natural light or unpolarized light) traveling toward the photosensor 900 is transmitted through the polarization reflective-transmissive element 20, and then is converted into the image light 103 with the circular polarization state by the first 1/4 wave plate 30; then, the image light 103 with circular polarization state will transmit through the set of lenses 40 to be converged and/or diverged; then, a portion of the image light 103 with circular polarization state is reflected by the partially reflective element 10 back to the set of lenses 40, and after passing through the set of lenses 40 to be converged and/or diverged, is converted into the image light 102 with second polarization state (e.g., S-polarized image light) by the first 1/4 wave plate 30; then, the image light 102 with the second polarization state will be reflected by the polarization reflective and transmissive element 20 back to the first 1/4 wave plate 30 to be converted into the image light 103 with circular polarization state by the first 1/4 wave plate 30; subsequently, the image light 103 with circular polarization state will transmit through the set of optics 40 to be converged and/or diverged; finally, a part of the image light 103 having the circular polarization state will transmit through the partially reflective element 10 to be received by the photosensor 900 for imaging, thereby implementing the image capturing function of the electronic device.

In summary, the imaging lens 1 of the present invention can fold back image light twice, so that the image light sequentially passes through the lens group 40 three times, that is, the imaging lens 1 sequentially uses the lens group 40 three times to converge and/or diverge the image light, so that the imaging lens 1 can ensure the imaging quality and effectively reduce the number of lenses in the lens group 40, which is helpful for reducing the volume and weight and reducing the cost.

It is noted that, as shown in fig. 3, when the imaging lens 1 is applied to an electronic device having an image source 800, the structure of the imaging lens 1 is also affected and limited by the polarization state of image light output by the image source 800. The above-described embodiment of the present invention uses the circularly polarized light image source 801 as the image source 800 for directly outputting the image light 103 having a circular polarization state as an example to explain the structural features and advantages of the imaging lens 1, but if the image source 800 is implemented as another type of image source for outputting image light having another polarization state, the structure of the imaging lens 1 needs to be specially designed and adjusted.

For example, fig. 5 shows a first variant implementation of the imaging lens 1 according to the above-described embodiment of the present invention, so that the imaging lens 1 according to the first variant implementation of the present invention is suitable for an electronic device having a linearly polarized image source 802 as an image source 800, wherein the linearly polarized image source 802 is capable of directly outputting the image light 101 having the first polarization state (e.g., P-polarized image light).

Specifically, the imaging lens 1 according to the first modified embodiment of the present invention is different from the above-described embodiment of the present invention in that: as shown in fig. 5, the imaging lens 1 further includes a second 1/4 wave plate 50, wherein the second 1/4 wave plate 50 is correspondingly disposed outside the partially reflective-transmissive element 10, that is, the second 1/4 wave plate 50 is located between the partially reflective-transmissive element 10 and the linearly polarized image source 802, so that the image light 101 with the first polarization state from the linearly polarized image source 802 is first converted into the image light 103 with the circular polarization state by the second 1/4 wave plate 50, and then is partially transmitted through the partially reflective-transmissive element 10, so as to realize the transmission of the image light between the partially reflective-transmissive element 10 and the polarized-transmissive element 20 in a folding manner.

In other words, as shown in fig. 5, the partially reflective transmissive element 10 in the imaging lens 1 is located between the first 1/4 wave plate 30 and the second 1/4 wave plate 50, and the first 1/4 wave plate 30 is located between the partially reflective transmissive element 10 and the polarization reflective element 20, so that the second 1/4 wave plate 50 in the imaging lens 1 corresponds to the linearly polarized image source 802, so that the image light 101 having the first polarization state from the linearly polarized image source 802 is converted into the image light 103 having the circular polarization state by the second 1/4 wave plate 50 before propagating to the partially reflective element 10.

It is understood that the imaging lens 1 according to this modified embodiment of the present invention is still suitable for an electronic device having a photosensor 900, wherein the photosensor 900 is correspondingly disposed at a position facing the second 1/4 wave plate 50 to receive the image light 101 with the first polarization state converted by the second 1/4 wave plate 50 for imaging, and the description of the present invention is omitted here.

As another example, fig. 6 shows a second variant implementation of the imaging lens 1 according to the above-described embodiment of the present invention, such that the imaging lens 1 according to the second variant implementation of the present invention is suitable for an electronic device having a natural light image source 803 (i.e., an unpolarized light image source) as an image source 800, wherein the natural light image source 803 is capable of directly outputting natural image light 100 (i.e., image light having an unpolarized state).

Specifically, the imaging lens 1 according to the second modified embodiment of the present invention is different from the above-described first modified embodiment of the present invention in that: as shown in fig. 6, the imaging lens 1 further includes a polarizing element 60 for converting unpolarized light into the image light 101 having the first polarization state. The polarizing element 60 is correspondingly disposed outside the second 1/4 wave plate 50, and the second 1/4 wave plate 50 is located between the polarizing element 60 and the partial anti-transmission element 10, that is, the polarizing element 60 is located between the second 1/4 wave plate 50 and the natural light image source 803, so that the natural image light 100 from the natural light image source 803 is first converted into the image light 101 with the first polarization state by the polarizing element 60, then converted into the image light 103 with the circular polarization state by the second 1/4 wave plate 50, and then partially transmitted through the partial anti-transmission element 10, so as to subsequently realize the image light to propagate between the partial anti-transmission element 10 and the polarization anti-transmission element 20 in a folded manner.

In other words, as shown in fig. 6, the second 1/4 wave plate 50 in the imaging lens 1 is located between the polarizing element 60 and the partially reflective transmissive element 10, and the first 1/4 wave plate 30 is located between the partially reflective element 10 and the polarized reflective element 20, so that the polarizing element 60 in the imaging lens 1 corresponds to the natural-light image source 803, so that the natural-image light 100 from the natural-light image source 803 is converted into the image light 101 with the first polarization state by the polarizing element 60 and then into the image light 103 with the circular polarization state by the second 1/4 wave plate 50 before propagating to the partially reflective element 10.

Preferably, as shown in fig. 6, the polarizing element 60 may be implemented as a polarizer 61 (e.g., an absorbing polarizer or a transflective polarizer) for directly converting non-polarized light (e.g., natural image light 100) into P-polarized image light (e.g., image light 101 having a first polarization state). Of course, in other examples of the present invention, the polarizing element 60 may also be implemented as a polarization splitting element (such as a PBS film, etc.) for transmitting P-polarized image light in non-polarized light (such as the natural image light 100) and converting the non-polarized light (such as the natural image light 100) into the P-polarized image light.

It is understood that the imaging lens 1 according to this variant embodiment of the present invention is still suitable for an electronic device having a photosensitive sensor 900, wherein the photosensitive sensor 900 is correspondingly disposed at a position facing the polarizing element 60 to receive the image light 101 with the first polarization state transmitted through the polarizing element 60 for imaging, and the description of the present invention is omitted here.

It is noted that, in order to reduce the interference of stray light, fig. 7 shows a third variant implementation of the imaging lens 1 according to the above-mentioned embodiment of the present invention, so as to further improve the imaging lens 1 of the present invention. Specifically, the imaging lens 1 according to the third modified embodiment of the present invention is different from the above-described second modified embodiment of the present invention in that: as shown in fig. 7, the imaging lens 1 further includes a parasitic light filtering element 70, wherein the parasitic light filtering element 70 is disposed outside the polarizing element 60, and the polarizing element 60 is located between the parasitic light filtering element 70 and the second 1/4 wave plate 50, that is, the parasitic light filtering element 70 is located between the polarizing element 60 and the natural light image source 803, so that the natural image light 100 from the natural light image source 803 is first filtered by the parasitic light filtering element 70 and then converted into the image light 101 with the first polarization state by the polarizing element 60, which helps to improve parasitic light interference.

It is noted that, as shown in fig. 7, the parasitic light filtering element 70 may be, but is not limited to, implemented as an 1/4 wave plate 71 having an angle of 45 degrees for filtering parasitic light in the image light, so that the parasitic light interference is improved. It will be appreciated that when the image source 800 is implemented as a natural light image source 803 to emit natural light, the 1/4 waveplate 71 provides for parasitic light filtering action as long as the polarizing element 60 is implemented as an absorptive polarizer, since absorptive polarizers, which are typically dichroic materials, absorb the orthogonal polarization component of one state and transmit the polarization component of the other state. When the image source 800 is implemented as the linearly polarized image source 802 to emit linearly polarized light, the polarizing element 60 may be any one of a trans-polarizing film, a polarization splitting film (e.g., a PBS film or a metal wire grid film), and an absorption polarizing film. Of course, since the circular polarization of the linear polarization state can be achieved when the fast and slow axes of the 1/4 wave plate 71 form an angle of 45 degrees with the polarization transmission axis direction of the polarizer 61, the 1/4 wave plate 71 is usually used at an angle of 45 degrees.

In addition, when the imaging lens 1 according to this modified embodiment of the present invention is applied to an electronic device having a photosensitive sensor 900, the photosensitive sensor 900 is correspondingly disposed at a position facing the stray light filtering element 70, so that the photosensitive sensor 900 can receive the image light with the stray light filtered out, which helps to improve the photosensitive imaging quality of the photosensitive sensor 900.

It should be noted that, although all the lenses 41 in the lens group 40 of the imaging lens 1 according to the above embodiment and the above modified embodiments of the present invention are located between the partial transflective element 10 and the first 1/4 wave plate 30, they are only examples. In other examples of the present invention, the lenses 41 in the lens group 40 may be located at other positions.

Exemplarily, fig. 8 shows a fourth variant implementation of the imaging lens 1 according to the above-described embodiment of the invention. Specifically, the imaging lens 1 according to the fourth modified embodiment of the present invention is different from the above-described third modified embodiment of the present invention in that: as shown in fig. 8, the lens group 40 of the imaging lens 1 may include two lenses 41, wherein one lens 41 is located between the partially reflective element 10 and the first 1/4 wave plate 30, and the other lens 41 is located between the first 1/4 wave plate 30 and the polarization reflective element 20, that is, the first 1/4 wave plate 30 is disposed between the two lenses 41 in the lens group 40, so that the image light 103 with circular polarization state transmitted through the partially reflective element 10 is transmitted through one lens 41 to be converged or diverged, and then is converted into the image light 102 with the second polarization state by the first 1/4 wave plate 30; then, the image light 102 with the second polarization state is transmitted through another lens 41 to be converged or diverged, and then reflected by the polarization reflective and transmissive element 20 back to the lens 41 of the lens group 40.

According to another aspect of the present invention, as shown in fig. 9, an embodiment of the present invention further provides an electronic device, wherein the electronic device may include an image source 800, a near-eye display device 2 and the imaging lens 1, and the imaging lens 1 is correspondingly disposed in an optical path between the image source 800 and the near-eye display device 2, so that the electronic device is implemented as a near-eye display device. The image source 800 is used to emit image light. The imaging lens 1 is configured to perform imaging processing on the image light from the image source 800, and transmit the image light after the imaging processing to the near-eye display device 2. The near-eye display device 2 is configured to display an image corresponding to the image light for a user to view.

It is noted that, as shown in fig. 9, the near-eye display device 2 of the present invention may be, but is not limited to, implemented as a waveguide, so as to laterally transmit the image light processed by the imaging lens 1 through the waveguide, and to be received and imaged by the eyes of the user after being coupled out of the waveguide. Of course, in other examples of the present invention, the near-eye display device 2 may also be implemented as a fold-back display, so that the image light processed by the imaging lens 1 is transmitted in a folded manner through the fold-back display, and can be received by the eyes of the user for imaging.

In addition, the image source 800 of the present invention can be implemented as an image source including a self-luminous display chip (e.g., Micro LED display chip or OLED display chip), so that the image source 800 of the electronic device can output image light without an additional configuration of an illumination system and a relay system, contributing to a substantial reduction in volume and weight of the electronic device. Of course, in other examples of the present invention, the image source 800 may also be implemented as an image source including a non-self-luminous display chip (e.g., an LCOS display chip, an LCD display chip, or a DMD display chip), and can output image light only by additionally configuring an illumination system and a relay system.

It is to be noted that although the electronic apparatus of the above-described embodiment of the present invention exemplifies a near-eye display apparatus to clarify the features and advantages of the present invention, in other examples of the present invention, the electronic apparatus may be implemented as an apparatus having an image pickup function such as an image pickup module or the like.

Fig. 10 shows an electronic device according to another embodiment of the present invention, wherein the electronic device may include a light sensor 900 and the imaging lens 1, wherein the imaging lens 1 is correspondingly disposed on a light sensing path of the light sensor 900, so that the electronic device is implemented as a camera module. The imaging lens 1 is configured to perform imaging processing on image light propagating along the photosensitive path. The photosensor 900 is configured to receive image light processed by the imaging lens 1 to form an image, so that the electronic apparatus has an image capturing function.

It will be appreciated by persons skilled in the art that the embodiments of the invention described above and shown in the drawings are given by way of example only and are not limiting of the invention. The objects of the invention have been fully and effectively accomplished. The functional and structural principles of the present invention have been shown and described in the examples, and any variations or modifications of the embodiments of the present invention may be made without departing from the principles.

Claims

1. An imaging lens for performing imaging processing on image light, comprising:

2. The imaging lens as claimed in claim 1, wherein all of the lenses of the set are disposed between the partially reflective element and the polarized reflective element.

3. The imaging lens as claimed in claim 1, wherein the partially reflective element is a partially reflective film plated on a surface of one of the lenses of the set or a light-transmissive substrate plated with a partially reflective film.

4. The imaging lens according to claim 1, wherein the polarization reflective and transmissive element is a polarization splitting film or a semi-reflective and semi-transmissive polarizer.

5. The imaging lens of any one of claims 1 to 4, further comprising a second 1/4 wave plate, wherein the second 1/4 wave plate is correspondingly disposed outside the partially reflective element, and the partially reflective element is located between the second 1/4 wave plate and the first 1/4 wave plate, wherein the second 1/4 wave plate is configured to interconvert image light having first and second polarization states with image light having a circular polarization state.

6. The imaging lens of claim 5, further comprising a polarizing element, wherein the polarizing element is correspondingly disposed outside the second 1/4 wave plate, and the second 1/4 wave plate is located between the polarizing element and the partially reflective element, wherein the polarizing element is configured to convert image light having a non-polarized state into image light having the first polarized state.

7. The imaging lens according to claim 6, wherein the polarizing element is a polarizing plate or a polarization splitting element.

8. The imaging lens of claim 6, further comprising a stray light filtering element, wherein the stray light filtering element is correspondingly disposed outside the polarization element, and the polarization element is located between the stray light filtering element and the second 1/4 wave plate, wherein the stray light filtering element is used for filtering stray light in the image light.

9. The imaging lens of claim 8, wherein the veiling glare filter is an 1/4 waveplate with a 45 degree angle.

10. An electronic device, comprising:

at least one image source for outputting image light;

11. An electronic device, comprising: