WO2019047006A1 - Optical module, head-mounted electronic device, and virtual reality system - Google Patents

Abstract

An optical module (100), a head-mounted electronic device, and a virtual reality system. The optical module (100) comprises, arranged in sequence from an object side to an image side, a first phase retardation film (10), a pellicle mirror (20), a second phase retardation film (30), and a reflective polarizer (40). The pellicle mirror (20) comprises an incident surface and a semi-reflective and semi-transmissive surface opposite the incident surface. The incident surface is directly opposite the first phase retardation film (10). The semi-reflective and semi-transmissive surface is directly opposite the second phase retardation film (30). The optical module (100) satisfies the following conditional expression: 0.97 < |fs|/|F| < 5 and 10 mm < |F| < 45 mm, where fs is the reflection focal length of the semi-reflective and semi-transmissive surface, and F is the focal length of the optical module (100).

Description

Optical modules, head-mounted electronics and virtual reality systems Technical field

The present invention relates to optical imaging technology, and more particularly to an optical module, a headset electronic device, and a virtual reality system.

Background technique

Due to the unreasonable design of the optical module, the head-mounted electronic device in the related art may have problems such as large size and low image definition, which limits the development of the head-mounted electronic device.

Summary of the invention

The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides an optical module, a headset electronic device, and a virtual reality system.

The optical module of the embodiment of the present invention includes a first phase retarder, a half mirror, a second phase retarder, and a reflective polarizer arranged in order from the object side to the image side;

The half mirror includes an incident surface and a semi-reflective semi-transmissive surface opposite to the incident surface, the incident surface facing the first phase retarder, the semi-reflective semi-transmissive surface facing the second phase Delay piece

The optical module satisfies the following conditional formula:

0.97<|fs|/|F|<5,

10mm<|F|<45mm,

Wherein fs is the reflection focal length of the semi-reflective semi-transmissive surface, and F is the focal length of the optical module.

The head mounted electronic device of the embodiment of the present invention includes the optical module and the screen of the above embodiment. The screen is located on the object side.

A virtual reality system according to an embodiment of the present invention includes the electronic device of the above embodiment; and a terminal that connects the head mounted electronic device.

In the optical module, the headset electronic device and the virtual reality system of the embodiment of the invention, due to the optics The module satisfies the above conditional formula, so that the optical module has the characteristics of small volume and clear imaging, so that the wearing electronic device using the above optical module has the characteristics of small volume and clear imaging, which is beneficial to the development of the wearing electronic device.

The additional aspects and advantages of the invention will be set forth in part in the description which follows.

DRAWINGS

The above and/or additional aspects and advantages of the present invention will become apparent and readily understood from

1 is a schematic structural view of an optical module according to Embodiment 1 of the present invention;

2 is an MTF diagram of an optical module according to Embodiment 1 of the present invention;

3 is a field curvature diagram of an optical module according to Embodiment 1 of the present invention;

4 is a distortion diagram of an optical module according to Embodiment 1 of the present invention;

5 is a schematic structural view of an optical module according to Embodiment 2 of the present invention;

6 is an MTF diagram of an optical module according to Embodiment 2 of the present invention;

7 is a field curvature diagram of an optical module according to Embodiment 2 of the present invention;

8 is a distortion diagram of an optical module according to Embodiment 2 of the present invention;

9 is a schematic structural view of an optical module according to Embodiment 3 of the present invention;

10 is an MTF diagram of an optical module according to Embodiment 3 of the present invention;

11 is a field curvature diagram of an optical module according to Embodiment 3 of the present invention;

Figure 12 is a distortion diagram of an optical module according to a third embodiment of the present invention.

The main component symbol description:

The optical module 100, the first phase retarder 10, the half mirror 20, the second phase retarder 30, the reflective polarizer 40, and the screen 50.

Detailed ways

The embodiments of the present invention are described in detail below, and the examples of the embodiments are illustrated in the drawings, wherein the same or similar reference numerals indicate the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the drawings are intended to be illustrative of the invention and are not to be construed as limiting.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", " Orientations of "post", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. The positional relationship is based on the orientation or positional relationship shown in the drawings, and is merely for the convenience of the description of the present invention and the simplified description, and is not intended to indicate or imply that the device or component referred to has a specific orientation, and is constructed and operated in a specific orientation. Therefore, it should not be construed as limiting the invention. Moreover, the terms "first" and "second" are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, features defining "first" or "second" may include one or more of the described features either explicitly or implicitly. In the description of the present invention, the meaning of "a plurality" is two or more unless specifically and specifically defined otherwise.

In the description of the present invention, it should be noted that the terms "installation", "connected", and "connected" are to be understood broadly, and may be fixed or detachable, for example, unless otherwise explicitly defined and defined. Connected, or integrally connected; may be mechanically connected, may be electrically connected or may communicate with each other; may be directly connected, or may be indirectly connected through an intermediate medium, may be internal communication of two elements or interaction of two elements relationship. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood on a case-by-case basis.

In the present invention, the first feature "on" or "under" the second feature may include direct contact of the first and second features, and may also include first and second features, unless otherwise specifically defined and defined. It is not in direct contact but through additional features between them. Moreover, the first feature "above", "above" and "above" the second feature includes the first feature directly above and above the second feature, or only It is only indicated that the first feature level is higher than the second feature. The first feature "below", "below" and "below" the second feature includes the first feature directly below and below the second feature, or merely the first feature level being less than the second feature.

The following disclosure provides many different embodiments or examples for implementing different structures of the present invention. In order to simplify the disclosure of the present invention, the components and arrangements of the specific examples are described below. Of course, they are merely examples and are not intended to limit the invention. In addition, the present invention may be repeated with reference to the numerals and/or reference numerals in the various examples, which are for the purpose of simplicity and clarity, and do not indicate the relationship between the various embodiments and/or arrangements discussed. Moreover, the present invention provides examples of various specific processes and materials, but one of ordinary skill in the art will recognize the use of other processes and/or the use of other materials.

Referring to FIG. 1, an optical module 100 according to an embodiment of the present invention includes a first phase retarder 10, a half mirror 20, a second phase retarder 30, and a reflective polarizer 40 arranged in order from the object side to the image side;

The half mirror 20 includes an incident surface S5 and a semi-reflective semi-transmissive surface S6 opposed to the incident surface S5. The incident surface S5 faces the first phase retarder 10, and the semi-reflective semi-transmissive surface S6 faces the second phase retarder 30. The optical module 100 satisfies the following conditional formula:

0.97<|fs|/|F|<5 (1), 10mm<|F|<45mm (2).

Where fs is the reflection focal length of the semi-reflective semi-transmissive surface S6, and F is the focal length of the optical module 100.

Specifically, the first phase retarder 10 and the second phase retarder 30 are, for example, 45-degree phase retarders. At this time, the first phase retarder 10 and the second phase retarder 30 can perform a 45-degree phase delay on the light.

The reflective polarizer 40 can achieve total reflection of orthogonally polarized light, and achieves transmitted light when aligned with the direction of polarized light.

The half mirror 20 is an optical amplifying core component of the optical module 100. The semi-reflective semi-transmissive surface S6 mainly affects the focal length of the optical module 100. The conditional expression (1) indicates that the optical module 100 is disposed by the reflected focal length of the half mirror 20. . If the reflection focal length fs focal length of the semi-reflective semi-transmissive surface S6 is too small (|fs|/|F|<0.97), it is difficult to correct the aberration of the optical module 100, resulting in unclear imaging of the optical module 100, and also causing the semi-reflective semi-transmissive surface S6 to be too curved, and adding the half mirror 20 The thickness is not conducive to miniaturization of the optical module 100.

If the reflection focal length fs focal length of the semi-reflective semi-transmissive surface S6 is too large (|fs|/|F|>5), it is necessary to configure other small focal length optical components to meet the focal length requirement of the optical module 100, which will increase the optical The number of lenses of the module 100 is not conducive to miniaturization of the optical module 100.

The conditional expression (2) indicates the focal length of the optical module 100. When the optical module 100 satisfies the conditional expression (2), it facilitates the configuration of the overall shape and performance of the optical module 100, and is applied to the head mounted electronic device in the optical module 100. At the time, it can meet the demand for miniaturization of head-mounted electronic devices.

The optical path principle of the optical module 100 is substantially as follows: the light from the object side (ie, the screen 50 in FIG. 1) sequentially passes through the first phase retarder 10, the half mirror 20, and the second phase retarder 30 to reach the reflective polarizer. 40. The light is reflected by the reflective polarizer 40 and then passes through the second phase retarder 30 again, and reaches the semi-reflective semi-transmissive surface S6 of the half mirror 40. The semi-reflective semi-transmissive surface S6 reflects the light to the reflective polarizer 40. The reflected light passes through the reflective polarizing plate 40 to the image side ST0 for imaging, and the effect of the magnification of the optical module 100 is achieved.

It can be understood that the optical module 100 described above can be applied to a head mounted electronic device such as glasses or a helmet, but is not limited to glasses and a helmet.

The head mounted electronic device of the embodiment of the present invention includes a screen 50 on the object side. Specifically, in the present embodiment, the screen 50 is opposite to the first phase retarder 10. The screen 50 is, for example, a liquid crystal display screen, and the screen 50 can illuminate the display screen. The light emitted by the screen 50 passes through the optical module 100 and reaches the image side image.

The virtual reality system (Virtual Reality System) of the embodiment of the present invention includes the above-described head mounted electronic device.

In summary, in the optical module 100, the headset electronic device, and the virtual reality system of the embodiment of the present invention, since the optical module 100 satisfies the above conditional expressions (1) and (2), the optical module is The utility model has the advantages of small volume, clear imaging and the like, and the head-mounted electronic device applying the optical module 100 has the characteristics of small volume and clear imaging, and is favorable for the development of the head-mounted electronic device.

Further, the virtual reality system further includes a terminal, and the terminal is connected to the headset. The terminal can control the image content displayed on the screen 50. For example, the terminal can control the screen 50 to play a movie program. The terminal is for example a mobile phone and/or a host server.

In some embodiments, the optical module 100 satisfies the following conditional formula:

0.7≤L/F≤2 (3);

Here, L is the distance from the surface S3 of the first phase retarder 10 near the object side to the surface S9 of the reflective polarizer 40 near the image side.

The conditional expression (3) describes the structural state of the optical module 100. When the L/F is less than 0.7, it is difficult to correct the aberration of the optical module 100, so that the optical module 100 is not imaged clearly; when the L/F is greater than 2, the optical mode is The volume of the group 100 is large, and when the optical module 100 satisfies the conditional expression (3), the overall length of the optical module 100 is effectively reduced, so that the optical module 100 has a small volume and a clear image.

In some embodiments, the optical module 100 satisfies the following conditional formula:

5mm ≤ L ≤ 40mm (4).

As such, the optical module 100 has a relatively small overall length and meets the requirements for miniaturization of the optical module 100.

In some embodiments, the entrance pupil distance H of the optical module 100 ranges from 10-20 mm.

In this way, when the optical module 100 is compact and the image is clear, the optical module 100 can obtain a large eye movement range, and the user can conveniently view the image formed by the optical module 100, which is beneficial to improving the user experience.

In some embodiments, the entrance face S5 of the half mirror 20 is convex.

As such, the incident surface S5 of the half mirror 20 is convex, which facilitates the focal length of the optical module 100 to be greater than 10 and less than 45, thereby facilitating miniaturization of the optical module 100.

In some embodiments, the half mirror 20 is an aspherical lens. The aspherical surface is determined by the following conditional expression:

Where X is the longitudinal distance between any point on the aspheric surface and the surface apex, r is the height from any point on the aspheric surface to the optical axis, c is the curvature of the vertex, k is the cone constant, and Ai is the correction coefficient of the i-th order of the aspheric surface.

In some embodiments, in order to reduce the lens cost of the optical module 100, the materials of the first phase retarder 10, the half mirror 20, the second phase retarder 30, and the reflective polarizer 40 are all plastic. The plastic is, for example, an acrylic material.

Embodiment 1:

Referring to FIG. 1 to FIG. 4, in the first embodiment, the optical module 100 satisfies the conditions of Tables 1 to 2 below:

Table 1

|fs|(mm)	31	F(mm)	18.32
H(mm)	10.00	L(mm)	25.00
Screen size (inch)	1.01	--	--

Table 2

Embodiment 2:

Referring to FIG. 5 to FIG. 8 , in the second embodiment, the optical module 100 satisfies the following conditions in Table 3 - Table 4:

table 3

|fs|(mm)	13.35	F(mm)	13.65
H(mm)	10.00	L(mm)	9.80
Screen size (inch)	0.70	--	--

Table 4

Embodiment 3:

Referring to FIG. 8 to FIG. 12, in the third embodiment, the optical module 100 satisfies the following conditions in Tables 5-6:

table 5

|fs|(mm)	39.80	F(mm)	23.00
H(mm)	10.00	L(mm)	30.00
Screen size (inch)	1.34	--	--

Table 6

In the description of the present specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiment", "example", "specific example", or "some examples", etc. The specific features, structures, materials or characteristics described in the embodiments or examples are included in at least one embodiment or example of the invention. In the present specification, the schematic representation of the above terms does not necessarily mean the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples.

While the embodiments of the present invention have been shown and described, the embodiments of the invention may The scope of the invention is defined by the claims and their equivalents.

Claims (10)

1. An optical module comprising: a first phase retarder, a half mirror, a second phase retarder, and a reflective polarizer arranged in order from the object side to the image side;

   The half mirror includes an incident surface and a semi-reflective semi-transmissive surface opposite to the incident surface, the incident surface facing the first phase retarder, the semi-reflective semi-transmissive surface facing the second phase Delay piece

   The optical module satisfies the following conditional formula:

   0.97<|fs|/|F|<5,

   10mm<|F|<45mm,

   Wherein fs is the reflection focal length of the semi-reflective semi-transmissive surface, and F is the focal length of the optical module.
2. The optical module according to claim 1, wherein the optical module satisfies the following conditional formula:

   0.7≤L/F≤2;

   Wherein L is a distance from a surface of the first phase retarder close to the object side to a surface of the reflective polarizer close to the image side.
3. The optical module according to claim 2, wherein the optical module satisfies the following conditional formula:

   5mm ≤ L ≤ 40mm.
4. The optical module according to claim 1, wherein the optical module has an entrance pupil distance ranging from 10 to 20 mm.
5. The optical module according to claim 1, wherein the incident surface is a convex surface.
6. The optical module of claim 1 wherein said half mirror is an aspherical lens.
7. The optical module according to claim 1, wherein the first phase retarder, the half mirror, the second phase retarder, and the reflective polarizer are made of plastic.
8. A head mounted electronic device, comprising:

   The optical module of any of claims 1-7; and

   a screen on the object side.
9. The head mounted electronic device of claim 8 wherein said head mounted electronic device comprises glasses and a helmet.
10. A virtual reality system, comprising:

    The head mounted electronic device of claim 8 or 9;

    a terminal that connects the head mounted electronic device.

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