WO2022011899A1

WO2022011899A1 - Optical system and projection apparatus

Info

Publication number: WO2022011899A1
Application number: PCT/CN2020/127364
Authority: WO
Inventors: 刘超; 丁卫涛
Original assignee: 歌尔股份有限公司
Priority date: 2020-07-16
Filing date: 2020-11-07
Publication date: 2022-01-20
Also published as: CN212391676U

Abstract

An optical system and a projection apparatus. The optical system sequentially comprises, in a light transmission direction: a light source (10); a first microlens array (20); and a display unit (30). The light source (10) comprises a light source panel (11) and one or more light source bodies (12) arranged on the light source panel (11). The first microlens array (20) comprises first microlens structures (21). The light source bodies (12) correspond one-to-one with the first microlens structures (21). The optical system and the projection apparatus of the invention aim to solve the problem in which a projection apparatus is heavy and bulky because a collimating lens assembly provided therein comprises a large number of optical lenses.

Description

Optical system and projection equipment

technical field

The utility model relates to the technical field of optical imaging, in particular to an optical system and a projection device.

Background technique

In traditional optical design, since the light source usually has a divergence angle when emitting light, in order to increase the light utilization rate of the light source and make all the light emitted by the light source enter the subsequent optical elements, a collimating mirror is usually installed on the light-emitting side of the light source. The light emitted by the light source is collimated by the collimating lens group. In order to ensure the collimation effect, the collimating lens group usually adopts a combination of multiple optical lenses. The mirror group directly affects the overall volume of the optical system of the micro-projection device. When the number of optical lenses in the collimating lens group is large, the weight and volume of the micro-projection device will increase, making the miniaturization of the micro-projection device more difficult.

The above content is only used to assist the understanding of the technical solutions of the present invention, and does not mean that the above content is the prior art.

Utility model content

The utility model provides an optical system and a projection device, aiming at solving the problem that the number of optical lenses of the collimating lens group used by the projection device for collimating light in the prior art is too large, which leads to the heavier weight and larger volume of the projection device. The problem.

In order to achieve the above purpose, the present invention proposes an optical system. The optical system includes a light source, a first microlens array and a display unit in sequence along the light transmission direction. The light source includes a light source panel and is distributed on the light source panel. At least one light source body, the first microlens array includes a first microlens structure, wherein each of the light source bodies is arranged in cooperation with one of the first microlens structures.

Optionally, the light source body is one of a miniature light-emitting diode and a miniature light-emitting diode.

Optionally, the light source body includes at least one sub-light source body, and the light exit direction of each of the sub-light source bodies is the same.

Optionally, the light source body includes a first sub-light source body, a second sub-light source body and a third sub-light source body, the first sub-light source body is a red light source, and the second sub-light source body is a green light source , the third sub-light source body is a blue light source.

Optionally, the optical system further includes a dichroic prism, and the dichroic prism is disposed on the light-emitting side of the first microlens array.

Optionally, the optical system further includes a homogenizing element, and the homogenizing element is provided between the first microlens array and the display unit.

Optionally, the homogenizing element includes a second microlens array, and a plurality of uniformly distributed second microlens structures are provided on both the light incident surface and the light exit surface of the second microlens array.

Optionally, the optical system further includes a relay lens group, and the relay lens group is arranged on the light-emitting side of the second microlens array.

Optionally, the display unit is one of a liquid crystal display, a digital light processor, a digital micromirror device, a liquid crystal attached silicon chip, an organic light emitting diode, and a microelectromechanical scanning galvanometer.

In order to achieve the above objective, the present application provides a projection device, the projection device includes a housing and the optical system according to any one of the above embodiments, and the optical system is accommodated in the housing.

The present application proposes an optical system. The optical system includes a light source, a first microlens array and a display unit in sequence along a light transmission direction. The light source includes a light source panel and at least one light source body distributed on the light source panel. The first microlens array includes a first microlens structure, wherein each of the light source bodies is arranged in cooperation with one of the first microlens structures. Specifically, the light emitted by the light source body on the light source panel passes through the corresponding first microlens structure, and the light is collimated after passing through the first microlens structure. The plurality of optical lenses in the straight lens group are collimated, and the first micro-lens structure can respectively collimate the light emitted by each of the light source bodies, so that the light emitted by the light elements can pass through all the light sources. The first micro-lens structure is used for collimation, thereby reducing the use of the collimating lens group for collimation or reducing the number of optical lenses in the collimating lens group, thereby reducing the weight and volume of the micro-projection device, and solving the problem in the prior art. The number of optical lenses of the collimating lens group used for collimating light in the projection device is large, which leads to the problems of heavier weight and larger volume of the projection device.

Description of drawings

In order to more clearly illustrate the embodiments of the present utility model or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are just some embodiments of the present invention, and for those of ordinary skill in the art, other drawings can also be obtained based on the structures shown in these drawings without any creative effort.

FIG. 1 is a schematic structural diagram of the optical system of the present invention.

Description of reference numbers:

标号label	名称 name	标号label		名称name
1010	光源 light source	3030	显示单元 Display unit
1111	光源面板 light source panel	4040	分光棱镜 Beam splitting prism
1212	光源本体 Light source body	5050	匀光元件dodging element
121121	子光源本体 Sub-light source body	5151	第二微透镜结构The second microlens structure
2020	第一微透镜阵列 first microlens array	6060	中继镜组Relay lens group
21twenty one	第一微透镜结构The first microlens structure

The realization, functional characteristics and advantages of the purpose of the present utility model will be further described with reference to the accompanying drawings in conjunction with the embodiments.

detailed description

The technical solutions in the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model. Obviously, the described embodiments are only a part of the embodiments of the present utility model, not all of them. Example. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the protection scope of the present invention.

It should be noted that all directional indications (such as up, down, left, right, front, back...) in the embodiments of the present invention are only used to explain the difference between the various components under a certain posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication also changes accordingly.

In addition, descriptions such as "first", "second", etc. in the present invention are only for description purposes, and should not be interpreted as indicating or implying their relative importance or implicitly indicating the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise expressly and specifically defined.

In the present utility model, unless otherwise expressly specified and limited, the terms "connection", "fixed" and the like should be understood in a broad sense, for example, "fixed" can be a fixed connection, a detachable connection, or an integrated; It can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal communication between two elements or the interaction relationship between the two elements, unless otherwise clearly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but must be based on the realization by those of ordinary skill in the art. When the combination of technical solutions is contradictory or cannot be realized, it should be considered that such technical solutions The combination does not exist and is not within the protection scope required by the present invention.

The utility model provides an optical system and a projection device.

Referring to FIG. 1 , the optical system sequentially includes a light source 10 , a first microlens array 20 and a display unit 30 along the light transmission direction. The light source 10 includes a light source panel 11 and at least one light source distributed on the light source panel 11 . The body 12 , the first microlens array 20 includes a first microlens structure 21 , wherein each of the light source bodies 12 is arranged in cooperation with one of the first microlens structures 21 .

In an optional embodiment, the microlens structure may be one of a triangular microlens structure, a hexagonal microlens structure, a quadrilateral microlens structure, a circular structure and a double-curvature microlens structure.

In an optional embodiment, the light source body 12 of the optical system is one of a Micro Light-Emitting Diode (Micro LED) and a Mini Light-Emitting Diode (Micro LED). , Specifically, the light source body 12 in the optical system is used to provide illumination light for the display unit 30 to form an illumination light path. Specifically, the light emitted by the light source body 12 passes through the first microlens array. After 20 collimation, it is transmitted to the display unit 30, and the display unit 30 transmits the light out of the optical system by means of transmission or reflection.

The present application proposes an optical system. The optical system includes a light source 10 , a first microlens array 20 and a display unit 30 in sequence along the light transmission direction. The light source 10 includes a light source panel 11 and a light source panel 11 . At least one light source body 12 , the first microlens array 20 includes a first microlens structure 21 , wherein each of the light source bodies 12 is arranged in cooperation with one of the first microlens structures 21 . Specifically, the light emitted from the light source body 12 on the light source panel 11 passes through the corresponding first microlens structure 21 , and the light is collimated after passing through the first microlens structure 21 . The light is collimated by the plurality of optical lenses in the collimating lens group, and the first microlens structure 21 can respectively collimate the light emitted by each of the light source bodies 12, so that the light source body 12 can be collimated. The emitted light is collimated through the first micro-lens structure 21, thereby reducing the use of the collimating lens group for collimation or reducing the number of optical lenses in the collimating lens group, thereby reducing the weight and weight of the micro-projection device. volume, which solves the problems in the prior art that the collimating lens group used by the projection device for collimating light has a large number of optical lenses, resulting in a heavier weight and larger volume of the projection device.

In an optional embodiment, the light source body 12 includes at least one sub-light source body 121 , and the light exit direction of each of the sub-light source bodies 121 is the same. In the prior art, since different sub-light source bodies 121 require corresponding collimating lens groups, in order to reduce the volume of the optical system, the different sub-light source bodies 121 are usually arranged according to different The light exit direction is set, and then the light emitted by different sub-light source bodies 121 is transmitted or refracted through optical elements such as dichroic mirrors, so as to realize the integration of light, but because different sub-light source bodies 121 are arranged in different directions, and Each sub-light source body 121 is provided with a separate collimating lens group, which results in a larger volume of the light source 10 . When a plurality of the sub-light source bodies 121 are arranged side by side, since each of the sub-light source bodies 121 is collimated by the micro-lens structure on the micro-lens array, there is no need to use an additional collimating lens group to align the sub-light source bodies The light emitted by 121 is collimated, and since different sub-light source bodies 121 do not interfere with each other when the collimating lens group is not used, the side-by-side arrangement of different sub-light source bodies 121 can be compared with inclined arrangement in different directions. The volume of the optical system is effectively reduced.

In a preferred embodiment, the light source body 12 includes a first sub-light source body, a second sub-light source body and a third sub-light source body, and the first sub-light source body is a red light emitting diode (Light Emitting Diode, LED) light source 10 , the second sub-light source body is a blue LED light source 10 , and the third sub-light source body is a green LED light source 10 . Specifically, the arrangement of the first sub-light source body, the second sub-light source body and the third sub-light source body can be adjusted according to a preset arrangement or actual requirements of the optical system. The arrangement of the sub-light source bodies, the second sub-light source bodies, and the third sub-light source bodies includes, but is not limited to, side-by-side arrangement or separate and spaced arrangement in sequence. The light emitted by each sub-light source body 121 is transmitted to the light incident surface of the corresponding microlens structure, and is collimated under the action of the microlens structure.

In an optional embodiment, the optical system further includes a beam splitter prism 40, and the beam splitter prism 40 is disposed on the light exit side of the first microlens. After the collimation of a microlens array 20 is transmitted to the display unit 30, the display unit 30 reflects the light after receiving the light, and transmits the reflected light to the projection device through the beam splitting prism 40 in the subsequent optical system. In a specific embodiment, when the display unit 30 is a reflective display unit 30, the optical system includes the beam splitting prism 40, and the beam splitting prism 40 can emit light, thereby adjusting the transmission of the light. direction, effectively reducing the volume of the optical system; when the display unit 30 is a transmissive display unit 30, the light passing through the first microlens array 20 directly enters the display unit 30, and the display unit 30 is in the After receiving the light, the light for imaging corresponding to the imaging image is emitted.

In an optional embodiment, the optical system further includes a light homogenizing element 50, and the light homogenizing element 50 is disposed between the first microlens array 20 and the display unit 30. Specifically, the After the light emitted by the light source body 12 passes through the first microlens array 20, since the light intensity of the light emitted by different sub-light source bodies 121 is not the same, and the light emitted by the sub-light source body 121 still has some light rays from the phase. The adjacent first microlens structure 21 passes through, so the light emitted by the light source body 12 will have uneven light intensity after passing through the first microlens array 20, and when the light with uneven light intensity When transmitted to the display unit 30, the light intensity of the light in different areas emitted by the display unit 30 will be different, thereby affecting the imaging quality of the optical system. In order to improve the above problem, the first microlens array 20 and the The uniform light element 50 is arranged between the display units 30, and the light passing through the first microlens array 20 is uniformized by the uniform light element 50, so that the light intensity of the light in each area is equal, thereby It can be ensured that the light intensity of the light in different areas received by the display unit 30 is equal, and the problem of different brightness and darkness in different areas of the imaging screen can be avoided.

In an optional embodiment, the homogenizing element 50 includes a second microlens array, and a plurality of uniformly distributed second microlens structures 51 are provided on both the light incident surface and the light exit surface of the second microlens array. Specifically, the second microlens array is used to homogenize the light passing through the first microlens array 20. In a preferred embodiment, the second microlens array is a double-sided microlens structure, and the The microlens structure is a circular microlens structure. It can be understood that the homogenizing element 50 may also perform homogenizing through other optical elements. Specifically, the homogenizing element 50 may further include a homogenizing sheet, a homogenizing rod, or a frosted glass.

In an optional embodiment, the homogenizing element 50 further includes a relay lens group 60, and the relay lens group 60 is arranged on the light-emitting side of the second microlens array. After the array of two microlenses, in order to shape the light emitted from the homogenizing element 50 and adjust the divergence angle of the light, the relay lens group 60 can be arranged on the light emitting side of the homogenizing element 50. The lens group 60 has a positive refractive power or a negative refractive power, and is used to adjust the divergence angle of the light. In a preferred embodiment, the relay lens group 60 has a positive refractive power.

In an optional embodiment, the display unit 30 is a liquid crystal display (Liquid Crystal Display, LCD), a digital light processor (Digital Light Processing, DLP), a digital micromirror device (Digital Micromirror Device, DMD), a liquid crystal display One of a silicon (Liquid Crystal on Silicon, LCOS) chip, an organic light emitting diode (Organic Light Emitting Display, OLED) and a Microelectromechanical Systems Scanning Mirror (Microelectromechanical Systems Scanning Mirror), it can be understood that the display unit 30 can also It is a laser light source of different wavelengths or other light sources that can emit light beams.

In an optional embodiment, the optical system may further include a phase retardation plate, the phase retardation plate is arranged between the beam splitting prism 40 and the display unit 30 , and specifically, is reflected by the beam splitting prism 40 The first linearly polarized light is converted into circularly polarized light or elliptically polarized light after passing through the phase retarder, and the circularly polarized light or elliptically polarized light changes after being reflected by the display unit 30. The circularly polarized light or the elliptically polarized light passes through the phase retarder again and is converted into a second linearly polarized light, the polarization direction of the second linearly polarized light is perpendicular to the polarization direction of the first linearly polarized light, and the second linearly polarized light is transmitted to the second linearly polarized light again. The beam splitting prism 40 is then transmitted through the beam splitting prism 40 and transmitted to the subsequent optical system of the rear projection device.

The present invention also provides a projection device, the projection device includes the optical system described in any of the above-mentioned embodiments, the specific structure of the optical system refers to the above-mentioned embodiment, because the optical system adopts all the above-mentioned embodiments. Therefore, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, and will not be repeated here.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the scope of the present invention. Any equivalent structural transformations made by using the contents of the description and drawings of the present invention under the inventive concept of the present invention, or Direct/indirect applications in other related technical fields are included in the scope of patent protection of the present invention.

Claims

An optical system, characterized in that the optical system includes a light source, a first microlens array and a display unit in sequence along a light transmission direction, the light source includes a light source panel and at least one light source body distributed on the light source panel, The first microlens array includes a first microlens structure, wherein each of the light source bodies is arranged in cooperation with one of the first microlens structures.
The optical system of claim 1, wherein the light source body is one of a miniature light-emitting diode and a miniature light-emitting diode.
The optical system according to claim 1, wherein the light source body includes at least one sub-light source body, and the light exit direction of each of the sub-light source bodies is the same.
The optical system of claim 1, wherein the light source body comprises a first sub-light source body, a second sub-light source body and a third sub-light source body, the first sub-light source body is a red light source, and the The second sub-light source body is a green light source, and the third sub-light source body is a blue light source.
The optical system according to claim 1, wherein the optical system further comprises a dichroic prism, and the dichroic prism is arranged on the light-emitting side of the first microlens array.
The optical system according to claim 1, characterized in that, the optical system further comprises a light homogenizing element, and the light homogenizing element is arranged between the first microlens array and the display unit.
6. The optical system according to claim 6, wherein the uniform light element comprises a second microlens array, and the light incident surface and the light exit surface of the second microlens array are provided with a plurality of uniformly distributed second microlens arrays. Microlens structure.
The optical system according to claim 7, wherein the optical system further comprises a relay lens group, and the relay lens group is arranged on the light-emitting side of the second microlens array.
The optical system according to claim 1, wherein the display unit is one of a liquid crystal display, a digital light processor, a digital micromirror device, a liquid crystal with a silicon chip, an organic light emitting diode, and a microelectromechanical scanning galvanometer. .
A projection device, characterized in that, the projection device comprises a housing and the optical system according to any one of claims 1-9, and the optical system is accommodated in the housing.