Imaging optics and systems

Abstract

The present invention discloses an imaging optical device, comprising a first prism, a second prism and a third prism, wherein the first prism is glued to the second prism, and the glued surface is the first glued surface; the second prism is glued to the third prism, and the glued surface is the second glued surface; the first glued surface and the second glued surface are plated with a multilayer film structure for polarization splitting. The present invention can combine the polarization splitting prisms of the illumination part and the imaging part to form an integral optical structure, making the structure more compact, reducing the volume, saving the number of optical devices, and the problem of parallel connection of stray light and main light is well solved in the optical path design, avoiding direct light leakage to the light output surface direction during the transmission process from the illumination part to the imaging part.

Description

Technical Field

[0001] The present invention relates to the field of optical technology, and in particular to an imaging optical device and system. Background Art

[0002] Most foldable projection devices are divided into two modules, an illumination module and an imaging module. The illumination module usually uses a reflective illumination device, usually a cube-shaped polarizing beam splitter prism. The imaging module is used to image the content displayed on the display on the focal plane into parallel light rays, which are directly observed by the human eye, or are introduced into a device such as an optical waveguide and then projected into the human eye. The usual form is a glued structure of a cube-shaped polarizing beam splitter prism and a spherical mirror, such as Figure 1 shown.

[0003] The structure of the traditional foldable projection device is not simple enough and it is difficult to reduce the total mass and volume. Summary of the invention

[0004] Embodiments of the present invention provide an imaging optical device and system. The purpose is to solve the problem of large size of imaging devices in the prior art. In order to have a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a general review, nor is it intended to identify key / important components or describe the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

[0005] In a first aspect, an embodiment of the present invention provides an imaging optical device, comprising a first prism, a second prism and a third prism, wherein:

[0006] The first prism is glued to the second prism, and the glued surface is a first glued surface;

[0007] The second prism is glued to the third prism, and the glued surface is the second glued surface;

[0008] The first bonding surface and the second bonding surface are plated with a multi-layer film structure for performing polarization splitting.

[0009] Optionally, the first prism includes a first triangular prism, the first surface of the first triangular prism is a first gluing surface, and the second surface and the third surface of the first triangular prism are configured as transmission surfaces.

[0010] Optionally, the second prism includes a second triangular prism, the first surface of the second triangular prism is a first gluing surface, the second surface of the second triangular prism is a second gluing surface, and the third surface of the second triangular prism is set as a reflecting surface.

[0011] Optionally, the third prism includes a third triangular prism, the first surface of the third triangular prism is the second gluing surface, the second surface of the third triangular prism is set as the reflection surface, and the third surface of the third triangular prism is set as the transmission surface.

[0012] Optionally, the light beam incident on the imaging optical device is not parallel to the light beam transmitted in the imaging optical device.

[0013] In a second aspect, an embodiment of the present invention provides an imaging optical system, comprising a light source, an image source, and any imaging optical device as described in the first aspect, wherein:

[0014] a light source for emitting a light beam toward an imaging optical device;

[0015] An image source, used for receiving the light beam emitted by the imaging optical device and generating an image light beam incident on the imaging optical device;

[0016] An imaging optical device is used to emit an image light beam.

[0017] Optionally, the light beam from the image source incident on the imaging optical device is not parallel to the light beam transmitted in the imaging optical device.

[0018] The technical solution disclosed in the embodiment of the present invention can combine the polarization splitting prisms of the illumination part and the imaging part to form an overall optical structure, making the structure more compact, reducing the volume, saving the number of optical devices, and solving the problem of parallel operation of stray light and main light in the optical path design, avoiding direct light leakage toward the light output surface during the transmission process from the illumination part to the imaging part.

[0019] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0021] Figure 1 is a schematic diagram of an optical device in the prior art disclosed in an embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of an imaging optical device disclosed in an embodiment of the present invention;

[0023] Figure 3 It is a schematic diagram of an imaging optical system disclosed in an embodiment of the present invention. DETAILED DESCRIPTION

[0024] The following description and accompanying drawings fully illustrate specific embodiments of the present invention so that those skilled in the art can practice them. The examples represent possible variations only. Unless explicitly required, separate components and functions are optional, and the order of operations can vary. Parts and features of some embodiments may be included in or replace parts and features of other embodiments. The scope of the embodiments of the present invention includes the entire scope of the claims, and all available equivalents of the claims. In this article, each embodiment may be represented individually or generally by the term "invention", which is only for convenience, and if more than one invention is in fact disclosed, it is not intended to automatically limit the scope of the application to any single invention or inventive concept. In this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, without requiring or implying any actual relationship or order between these entities or operations. Moreover, the term "include", "comprise" or any other variant thereof is intended to cover non-exclusive inclusion, so that the process, method or device including a series of elements includes not only those elements, but also other elements that are not explicitly listed. The various embodiments are described in a progressive manner herein, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other. As for the structures, products, etc. disclosed in the embodiments, since they correspond to the parts disclosed in the embodiments, the description is relatively simple, and the relevant parts can be referred to the description of the method part.

[0025] The embodiment of the present invention discloses an imaging optical device, such as Figure 2 As shown, it includes a first prism, a second prism and a third prism, wherein,

[0026] The first prism is glued to the second prism, and the glued surface is a first glued surface;

[0027] The second prism is glued to the third prism, and the glued surface is the second glued surface;

[0028] The first bonding surface and the second bonding surface are plated with a multi-layer film structure for performing polarization splitting.

[0029] The first prism and the second prism are glued together to form a polarization splitter prism structure. Similarly, the second prism and the third prism are glued together to form a polarization splitter prism structure. Therefore, in the imaging optical device, the use of three prisms can achieve the polarization splitting effect of the two parts of light, illumination and imaging.

[0030] In the imaging optical device, the polarization beam splitting prisms of the illumination part and the imaging part can be combined to form an integral optical structure, making the structure more compact, reducing the volume, and saving the number of optical devices.

[0031] Specifically, the first prism may include a first triangular prism, the first surface of the first triangular prism is a first gluing surface, and the second surface and the third surface of the first triangular prism are configured as transmission surfaces.

[0032] Further, the second prism includes a second triangular prism, the first surface of the second triangular prism is a first gluing surface, the second surface of the second triangular prism is a second gluing surface, and the third surface of the second triangular prism is set as a reflecting surface.

[0033] Furthermore, the third prism includes a third triangular prism, the first surface of the third triangular prism is the second bonding surface, the second surface of the third triangular prism is set as a reflection surface, and the third surface of the third triangular prism is set as a transmission surface.

[0034] Among them, the reflective surface and the transmissive surface can also be coated to achieve better optical performance.

[0035] In particular, Figure 1 In the prior art shown, the light emitted from the image source is parallel to the light subsequently propagating in the optical device or the light emitted from the optical device, which may reduce the imaging quality of the imaging optical device during implementation.

[0036] like Figure 2 In the imaging optical device shown, the light beam incident on the imaging optical device and the light beam emitted from the imaging optical device may not be parallel.

[0037] Furthermore, the light beam incident on the imaging optical device may not be parallel to any light beam subsequently propagating in the optical device. For example, it may not be parallel to any light beam after the first reflection.

[0038] Specifically, the plane of the light entrance of the imaging optical device may not be parallel to the plane of the light exit, but the present invention does not limit the directions of the first bonding surface and the second bonding surface. When the second prism includes a cubic prism, etc., the first bonding surface and the second bonding surface may be parallel to each other. Figure 2 The imaging optical device shown in the figure, the embodiment of the present invention also discloses an imaging optical system, such as Figure 3 As shown, it includes a light source, an image source and an imaging optical device, wherein,

[0039] a light source for emitting a light beam toward an imaging optical device;

[0040] An image source, used for receiving the light beam emitted by the imaging optical device and generating an image light beam incident on the imaging optical device;

[0041] An imaging optical device is used to emit an image light beam.

[0042] Generally, the light beam emitted by the light source can be transmitted through the second surface of the first prism into the imaging optical device, reflected by the first surface of the first prism, transmitted through the third surface of the first prism, and irradiated on the image source. After being reflected and imaged by the image source, the light beam is again transmitted through the third surface of the first prism into the imaging optical device, and after being transmitted through the first surface of the first prism, it enters the second prism.

[0043] Furthermore, the light beam entering the second prism is reflected by the third surface of the second prism, and then transmitted from the second surface of the second prism into the third prism.

[0044] Furthermore, the light beam entering the third prism is reflected by the second surface of the third prism, and then emitted to the first surface of the third prism, that is, the second bonding surface, and then emitted from the third surface of the third prism after reflection.

[0045] In the imaging optical system, the light source may include but is not limited to a light emitting diode (LED), and the image source may include but is not limited to a liquid crystal on silicon (LCOS) display, etc. Those skilled in the art may select a suitable light source and image source during the specific implementation process.

[0046] exist Figure 3 In the imaging optical system shown, the light beam from the image source incident on the imaging optical device may be non-parallel to the light beam emitted from the imaging optical device.

[0047] Furthermore, the light beam incident from the image source to the imaging optical device may not be parallel to any light beam subsequently propagating in the optical device. For example, it may not be parallel to any light beam after the first reflection.

[0048] The light emitted by the image source included in the imaging optical system is transmitted into the second prism and reflected by the third surface of the second prism. The propagation direction of all subsequent light rays is different from the direction of the light emitted by the image source, thereby avoiding direct light leakage to the light output surface during the transmission process from the illumination part to the imaging part. The problem of parallel transmission of stray light and main light is well solved in the optical path design, and the imaging quality of the imaging optical system is effectively improved. In the imaging optical system disclosed in the embodiment of the present invention, it is avoided that the light is directly emitted toward the output end when it is from the illumination part to the imaging part, so that stray light can be prevented from entering the display system and the imaging quality is improved.

[0049] It should be understood that the present invention is not limited to the processes and structures described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. An imaging optical system, comprising a light source, an image source and an imaging optical device, in, The light source is used to emit a light beam to the imaging optical device; The image source is used to receive the light beam emitted by the imaging optical device and generate an image light beam to be incident on the imaging optical device; The imaging optical device is used to emit an image light beam, and the imaging optical device includes a first prism, a second prism and a third prism. The first prism and the second prism are glued together, and the glued surface is a first glued surface; The second prism is glued to the third prism, and the glued surface is a second glued surface; The first bonding surface and the second bonding surface are coated with a multi-layer film structure for polarization splitting; The light beam from the image source incident on the imaging optical device is transmitted through the first prism, enters the second prism, is reflected in the second prism, enters the third prism, and is reflected in the third prism before being emitted from the imaging optical device. Furthermore, the light beam from the image source incident on the imaging optical device is not parallel to the light beam transmitted in the imaging optical device.

2. The imaging optical system according to claim 1, It is characterized in that The first prism includes a first triangular prism, a first surface of the first triangular prism is the first gluing surface, and a second surface and a third surface of the first triangular prism are configured as transmission surfaces.

3. The imaging optical system according to claim 1, It is characterized in that The second prism includes a second triangular prism, a first surface of the second triangular prism is the first gluing surface, a second surface of the second triangular prism is the second gluing surface, and a third surface of the second triangular prism is set as a reflecting surface.

4. The imaging optical system according to claim 1, It is characterized in that The third prism comprises a third triangular prism, the first surface of the third triangular prism is the second gluing surface, the second surface of the third triangular prism is set as a reflection surface, and the third surface of the third triangular prism is set as a transmission surface.

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