CN211206838U - light guiding optics - Google Patents

Abstract

The utility model relates to a light-guiding optical component, including a first inclined surface and a second inclined surface in which a transparent light guide is arranged. The transparent light guide includes a side surface facing a first direction, and a first surface and a second surface adjacent to the side surface and facing each other. The first inclined surface extends from the first surface to the second surface. The second inclined surface is located on the other side of the first inclined surface facing the side surface, and the second inclined surface extends from the first surface to the second surface. When input light enters the transparent light guide, the input light is reflected by the first inclined surface and the second inclined surface to form an output light output by the transparent light guide.

Description

light guiding optics

technical field

The utility model relates to a light-guiding optical assembly, in particular to a light-guiding optical assembly that reflects part of light through a plurality of inclined surfaces in a light guide to guide the light.

Background technique

Light-guide optical element (LOE) is usually used in smartphones, head-up displays, audio-visual players, or any other mobile display devices, such as head-mounted displays in augmented/virtual reality systems (head-mounted displays, HMD). The light guiding optical assembly is a component in the entire imaging system. When the light source device in the imaging system outputs light, the light guiding optical assembly passes through a plurality of inclined reflection planes disposed therein at a specific angle and the inner surface of the entire assembly. , the light is coupled out to the user's eyes by single to multiple reflections by partial reflection/diffraction or total internal reflection.

The thinning of devices is a development trend. However, when connecting with other devices, the light guide components that are too thin also have the characteristics of being relatively fragile, especially at the connection places, which are too thin to be firmly adhered.

In addition to this, the inner surface of the light-guiding optical assembly is also an important link in the light-guiding process, with partial reflection/diffraction through the inclined reflective plane to guide the light to the inner surface of the light-guiding optical assembly; and The light is trapped by total internal reflection through the inner surface, and finally guided to the user's eye after multiple reflection/diffraction and total internal reflection. In order for the component to achieve this effect, the high precision of the component is an important condition.

According to the above, although the light guiding optical components in the prior art can be used in various display devices, however, many inclined reflection planes and high-precision quality requirements increase the manufacturing cost, and the production yield is difficult Lift, and the thin shape is difficult to stabilize when adhering to other devices. Therefore, the present invention provides a light-guiding optical assembly, which solves the above-mentioned problems faced by the existing light-guiding optical assembly, and further improves the implementation and utilization in the industry.

Utility model content

In view of the above problems, the purpose of the present invention is to provide a light guide optical assembly, which only reflects part of the light through the inclined surface to achieve the effect of light guide, so as to improve the above problems caused by the prior art.

According to the purpose of the present invention, a light guide optical assembly is provided, including a transparent light guide body, the transparent light guide body includes a side surface facing a first direction, a first surface adjacent to the side surface and facing each other, and second surface. The transparent light guide body includes a first inclined surface extending from the first surface to the second surface, the first inclined surface and the first surface form a first angle, and the geometric center of the first inclined surface and the geometric center of the side surface a first distance apart; and a second inclined surface extending from the first surface to the second surface, the second inclined surface is located on the other side of the first inclined surface toward the side surface, and forms a second angle with a surface, and the second inclined surface is The geometric center of the inclined surface is a second distance from the geometric center of the side surface. Wherein, when the input light enters the transparent light guide body, the output light is formed by the input light reflected by the first inclined surface and the second inclined surface, and then is outputted outside the transparent light guide body.

Preferably, the first angle and the second angle may be equal.

Preferably, the light-guiding optical assembly may further include a first reflective layer disposed on the first inclined surface and a second reflective layer disposed on the second inclined surface. Wherein, the reflectivity of the first reflective layer is greater than that of the first inclined surface, and the reflectivity of the second reflective layer is greater than that of the second inclined surface.

Preferably, the light guiding optical assembly may further include a third inclined surface extending from the first surface to the second surface, the third inclined surface is located on the other side of the second inclined surface facing the first inclined surface, and the third inclined surface is connected to the second inclined surface. The first surface contains a third angle, and the geometric center of the third inclined surface is separated from the geometric center of the second inclined surface by a third distance. The second distance is not equal to the third distance.

Preferably, the first angle, the second angle and the third angle may be equal.

Preferably, the light-guiding optical assembly may further include a first reflective layer disposed on the first inclined surface, a second reflective layer disposed on the second inclined surface, and a third reflective layer disposed on the third inclined surface. The reflectivity of the first reflective layer is greater than that of the first inclined plane, the reflectivity of the second reflective layer is greater than that of the second inclined plane, and the reflectivity of the third reflective layer is greater than that of the third inclined plane.

Preferably, the reflectivity of the third reflective layer may be greater than the reflectivity of the second reflective layer and the reflectivity of the first reflective layer.

Preferably, the light guide optical assembly may further include a transparent member covering the first surface and the second surface, and the material of the transparent member may include glass plastic or resin.

The light guiding optical assembly of the present invention uses inclined surfaces with specific spacing to reflect the input light and guide the light to a specific direction. The light guiding optical assembly of the present invention has relatively few inclined surfaces, so that the manufacturing cost of the inclined surfaces is low, and the structural design that needs to use total internal reflection is not limited, and a certain range of first surface and The inclination angle of the second surface effectively increases the production yield, thereby improving the aforementioned existing problems.

Description of drawings

FIG. 1 is a schematic structural diagram of the first embodiment of the light guiding optical assembly of the present invention.

FIG. 2 is a schematic view of the operation of the first embodiment of the light guiding optical assembly of the present invention.

FIG. 3 is a schematic structural diagram of a second embodiment of the light guiding optical assembly of the present invention.

FIG. 4 is a schematic structural diagram of a third embodiment of the light guiding optical assembly of the present invention.

FIG. 5 is a schematic structural diagram of a fourth embodiment of the light guide optical assembly of the present invention.

6 is a schematic structural diagram of a fifth embodiment of the light guiding optical assembly of the present invention.

FIG. 7 is a schematic diagram of the light guiding optical assembly of the present invention collocated with an optical machine.

Description of reference numbers:

1, 2, 3, 4...Transparent light guide

10...side surface

21...first surface

22...Second surface

31...First inclined plane

32...Second slope

33...Third slope

34...Fourth inclined plane

35...Fifth inclined plane

40...Transparent components

41...Transparent component substrate

42...Transparent component board

51...first reflective layer

52...second reflective layer

DR1...first direction

d1...first distance

d2...Second distance

d3...Third distance

d4...fourth distance

d5...fifth distance

E...eye

LG…Light Guiding Optical Assemblies

Li...input light

Lo...output light

LE...Optical machine

θ1...first angle

θ2...Second angle

θ3...third angle

θ4...fourth angle

θ5...5th angle

Detailed ways

In order to facilitate the understanding of the technical features, content and advantages of the present invention and the effects that can be achieved, the present invention is hereby described in detail with the drawings and the expression form of the embodiments as follows, and the drawings used therein, which The purpose is only for the purpose of illustrating and assisting the description, not necessarily the real proportion and precise configuration after the implementation of the present invention, so the proportion and configuration relationship of the attached drawings should not be interpreted or limited to the actual implementation of the present invention. Requirement, please describe first. And for ease of understanding, the same components in the following embodiments are described with the same reference numerals.

In the description of the present invention, it should be noted that, unless otherwise expressly specified and limited, the terms "arrangement", "connection" and "adjacent" should be understood in a broad sense, for example, "connection" may be a fixed connection , can also be detachable connection, or integrally connected; can be directly connected, or indirectly connected through an intermediate medium, and can be internal communication between two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood in specific situations.

Please refer to FIG. 1 , which is a schematic structural diagram of the first embodiment of the light guiding optical assembly of the present invention.

As shown in the figure, the light guide optical assembly of the present invention includes a transparent light guide body 1 , including a side surface 10 , a first surface 21 , a second surface 22 , a first inclined surface 31 and a second inclined surface 32 . The side surface 10 faces the first direction DR1, and the first surface 21 and the second surface 22 are adjacent to the side surface 10 and face each other. In this embodiment, the first surface 21 and the second surface 22 may be parallel to each other. In other embodiments, the first surface 21 and the second surface 22 may not be parallel to each other. For example, the first surface 21 The second surface 22 can be curved to form a concave lens, so that the image light penetrated by the second surface 22 can produce a refraction effect, which can be used as a vision correction lens.

The first inclined surface 31 extends from the first surface 21 to the second surface 22 , and the included angle with the first surface 21 is the first angle θ1 , and the second inclined surface 32 extends from the first surface 21 to the second surface 21 . The surface 22, and the included angle with the first surface 21 is the first angle θ2. In this embodiment, the first angle θ1 may be in the range of 35 degrees to 70 degrees, and the second angle θ2 may be in the range of 35 degrees to 70 degrees. For example, the first angle θ1 may be an angle of 45 degrees, and the second angle θ2 may be an angle of 45 degrees, that is, the first inclined surface 31 and the second inclined surface 32 are parallel to each other. In practical application, depending on the shape design, the angle can be 35 degrees or 75 degrees at the same time.

Besides, the geometric center of the first inclined surface 31 is separated from the geometric center of the side surface 10 by a first distance d1, and the geometric center of the second inclined surface 32 is separated from the geometric center of the first inclined surface 31 by a second distance d2, according to Different applications can have different designs.

Please refer to FIG. 2 , which is a schematic diagram of the operation of the first embodiment of the light guiding optical assembly of the present invention.

As shown, the input light ray Li enters the light guiding optical assembly from the side surface 10 . When the input light Li advances along the incident direction and contacts the first inclined surface 31, a part of the input light Li is reflected by the first inclined surface 31 to form the output light Lo, leaves the transparent light guide body 1 through the first surface 21, and enters into use in the eyes of the person E. In addition, part of the input light ray Li will penetrate the first inclined surface 31 and continue to advance along the incident direction. When the input light ray Li touches the second inclined surface 32, it is also partially reflected to form the output light ray Lo, which passes through the first surface 21. It leaves the transparent light guide body 1 and enters the user's eye E. However, the present invention is not limited to this. For example, the input light Li is not limited to enter the transparent light guide body 1 from the side surface 10 , but can also enter from the first surface 21 on the contrary, form the output light Lo and then leave the side surface 10 Transparent light guide 1.

Furthermore, the design between the first distance d1 and the second distance d2 mentioned above is determined according to the distance of the light from the eye E to be focused after the light leaves the transparent light guide body 1 . For example, when the eye E is closer to the transparent light guide body, the numerical difference between the first distance d1 and the second distance d2 may become larger. Or on the contrary, when the eye E is farther away from the transparent light guide body 1 (for example, greater than 500 mm), the values of the first distance d1 and the second distance d2 are closer.

The light guiding optical component in the first embodiment uses the first inclined surface 31 and the second inclined surface 32 to partially reflect the input light Li to the eyes E of the user. It is worth noting that in the process of guiding the light , it is not limited that the first surface 21 and the second surface 22 must be on the path of the light guide, so the inclination angle of the first surface 21 and the second surface 22 can be allowed to be within a predetermined (or set) range, and the The light directing optics maintain the same function.

Please refer to FIG. 3 , which is a schematic structural diagram of a second embodiment of the light guiding optical assembly of the present invention.

As shown in the figure, the transparent light guide body 2 includes a side surface 10 , a first surface 21 , a second surface 22 , a first inclined surface 31 , a second inclined surface 32 , a first reflection layer 51 and a second reflection layer 52 (represented by different dashed lines). Among them, the side surface 10 , the first surface 21 , the second surface 22 , the first inclined surface 31 , and the second inclined surface 32 may be the same as those described in the first embodiment, and thus repeated descriptions are omitted.

The first reflection layer 51 is disposed on the first inclined surface 31 , and the second reflection layer 52 is disposed on the second inclined surface 32 . The first reflection layer 51 may have a higher reflectivity than the first inclined surface 31 , and the second reflection layer 52 may have a higher reflectance than the second inclined surface 32 . For example, the manufacturing method can be to cut the base material of the transparent light guide 1 at a specific angle to form a plurality of blocks with inclined surfaces to form inclined surfaces, and then use a coating technology (eg, vacuum sputtering or evaporation), etc. A thin film is coated on the aforementioned inclined surface; the thin film can be composed of a transparent or translucent dielectric material, and can be selected from multilayer dielectric films, metal (Al or Ag) oxide reflective films and combinations thereof. formed group. The film can be a single layer or a stacked multilayer film.

The first reflection layer 51 and the second reflection layer 52 have a reflectance of 5% to 50% in a wavelength range of 420 nm to 700 nm. Then, the inclined surfaces are connected to each other to form a transparent light guide body 2 including a reflective layer. The connection method here includes adhesion, bonding, etc., but the present invention is not limited to this, and other connection methods are also applicable to this embodiment.

Please refer to FIG. 4 , which is a schematic structural diagram of a third embodiment of the light guiding optical assembly of the present invention.

As shown in the figure, the transparent light guide 3 includes a side surface 10 , a first surface 21 , a second surface 22 , a first inclined surface 31 , a second inclined surface 32 and a third inclined surface 33 . The side surface 10 , the first surface 21 , the second surface 22 , the first inclined surface 31 , and the second inclined surface 32 may be similar to the components described in the first embodiment, so the related content will not be repeated.

In the third embodiment, the third inclined surface 33 extends from the first surface 21 to the second surface 22 , and is separated from the first inclined surface 31 by the second inclined surface 32 . When the third inclined surface 33 is provided, the third inclined surface 33 and the first surface 21 sandwich a third angle θ3, and the first angle θ1 and the second angle θ2 can be in the range of 35 degrees to 70 degrees; the third inclined surface 33 and the The first surface 21 sandwiches a third angle θ3, and the third angle θ3 may be in a range, and may be 35 degrees to 70 degrees. For example, when the first angle θ1 and the second angle θ2 are 45 degrees, and the third angle θ3 is also 45 degrees, the first inclined surface 31 , the second inclined surface 32 and the third inclined surface 33 are mutually parallel.

Further, when the third inclined surface 33 is provided, the geometric center of the third inclined surface 33 is separated from the geometric center of the second inclined surface 32 by a third distance d3. The difference between the three distances d3 is also related to the design. When the product design needs to focus on different positions, the second distance d2 and the third distance d3 will be more similar as the position of the eye E to be focused is farther away. It should be noted that the second distance d2 and the third distance d3 are not equal, that is, the distances between the inclined surfaces are not equal to each other.

Referring to the embodiment of FIG. 3 , the transparent light guide 3 in this embodiment may be further provided with a reflective layer on the inclined surface, for example, a first reflective layer is coated on the first inclined surface 31 , or a first reflective layer is coated on the first inclined surface 31 by spraying. A reflective layer, and so on, the second reflective layer disposed on the second inclined surface 32 and the third reflective layer disposed on the third inclined surface 33 can also be formed in the same way. Wherein, the first reflective layer, the second reflective layer and the third reflective layer respectively have higher reflectance than the first inclined surface, the second inclined surface and the third inclined surface.

In addition, by changing the composition of the material or the thickness of the coating, the first reflective layer can have a lower reflectivity than the second reflective layer and the third reflective layer, and the third reflective layer has a lower reflectivity than the first reflective layer. The reflective layer and the second reflective layer have higher reflectivity. For example, the reflectivity of the first reflective layer may be 5%-15%, the reflectivity of the second reflective layer may be 20%-30%, and the reflectivity of the third reflective layer may be 35%-45%.

In the third embodiment, the first inclined surface 31 , the second inclined surface 32 and the third inclined surface 33 are arranged in the transparent light guide body 1 at unequal intervals to reduce the input light Li that is not reflected by the inclined surface. Bright and dark lines occur. In addition, films with different compositions or thicknesses can also be arranged on the inclined surface according to requirements, so as to control the reflectivity of each reflective layer to be different.

Please refer to FIG. 5 , which is a schematic structural diagram of a fourth embodiment of the light guiding optical assembly of the present invention.

As shown in the figure, the transparent light guide body 4 includes a side surface 10 , a first surface 21 , a second surface 22 , a first inclined surface 31 , a second inclined surface 32 , a third inclined surface 33 , and a fourth inclined surface 34 and the fifth inclined surface 35 . Among them, the side surface 10 , the first surface 21 , the second surface 22 , the first inclined surface 31 , the second inclined surface 32 and the third inclined surface 33 can be similar to those described in the third embodiment, so they will not be repeated. Describe the relevant content.

In this embodiment, the transparent light guide body 4 is further provided with a fourth inclined surface 34 and a fifth inclined surface 35 extending from the first surface 21 to the second surface 22 . In this embodiment, when the fourth inclined surface 34 and the fifth inclined surface 35 are provided, the fourth inclined surface 34 and the first surface 21 sandwich the fourth angle θ4, and the fifth inclined surface 35 and the first surface 21 sandwich the fifth Angle θ5. In this embodiment, the first angle θ1 may be in the range of 35 degrees to 70 degrees, the second angle θ2 may be in the range of 35 degrees to 70 degrees, and the third angle θ3 may be in the range of 35 degrees to 70 degrees , the fourth angle θ4 may be in the range of 35 degrees to 70 degrees, and the fifth angle θ5 may be in the range of 35 degrees to 70 degrees. As in the previous embodiment, when the first angle θ1, the second angle θ2, the third angle θ3, the fourth angle θ4 and the fifth angle θ5 are equal, it means that the first inclined surface 31, the second inclined surface 32 and the third inclined surface are The surface 33 , the fourth inclined surface 34 and the fifth inclined surface 35 are parallel to each other.

Further, when a fourth inclined surface 34 and a fifth inclined surface 35 exist, the geometric center of the fourth inclined surface 34 is separated from the geometric center of the third inclined surface 33 by a fourth distance d4, and the geometric center of the fifth inclined surface 35 is separated by a fourth distance d4. It is a fifth distance d5 from the geometric center of the fourth inclined surface 34 . And it should be noted that the pitches between the inclined surfaces are not equal to each other.

The embodiments of the present invention can be further described by the following examples, and the detailed parameters of the examples are shown in Table 1.

Table 1

Among them, "N/A" means that the instance does not define this parameter.

As shown in Table 1, it can be seen that, compared with the angle of the comparative example, the angle between each inclined surface and the first surface 21 of the example of the present invention is usually 45 degrees, and the total internal reflection is avoided in use to reduce each Due to the angle error (tolerance), the block screen part causes the screen to be cut off or overlapped. However, as the distance between the inclined surfaces to be focused on the eye E is farther (eg, >500 mm or more), the distance between them will be closer to equal distance.

Please refer to FIG. 6 , which is a schematic structural diagram of a fifth embodiment of the light guiding optical assembly of the present invention.

As shown in the figure, the light guide optical assembly further includes a transparent member 40 to cover the transparent light guide body 1 so that the first surface 21 and the second surface 22 are located in the transparent member 40 without contacting the outside. The transparent member 40 may be made of the same material as the transparent light guide body 1, or may be glass, plastic or resin. For example, a transparent member base material 41 having a groove corresponding to the shape of the transparent light guide body 1 is obtained by cutting, the transparent light guide body 1 is placed in it, and the The entire transparent light guide body 1 is encapsulated by the transparent member plate 42 so that the first surface 21 and the second surface 22 are not in contact with the outside. In another embodiment, an embedding (or double embedding) technique is used to encapsulate the transparent light guide body 1 . For example, the transparent light guide body 1 is immersed in a liquid resin in a rectangular mold. The resin can be a thermosetting resin or a photocurable resin. When the resin is cured by heating or UV light, and taken out from the mold, the Resin encapsulated transparent light guide body 1 . However, the present invention is not limited to that all surfaces described in the embodiments are covered by the transparent member, only the first surface 21 and the second surface 22 may be covered by the transparent member, and the covering process may include lamination, adhesion and other related connection technologies. By wrapping the transparent light guide body in the transparent member, the light guide optical assembly of the present invention can be further protected, and the light guide optical assembly can be prevented from being damaged by dust or sharp objects during use.

Please refer to FIG. 7 , which is a schematic diagram of the light-guiding optical assembly of the present invention collocated with an optical machine.

As shown in the figure, the light guiding optical assembly LG of the present invention is usually used with a light engine LE (light engine) system, and the light engine LE can be a spatial light modulator (SLM), such as a cathode Cathode ray tube (CRT), organic light emitting diode array (OLED), liquid crystal display (LCD), liquid crystal on silicon (LCoS) or digital light processing, DLP), etc., any means known to those of ordinary skill in the art. For example, the opto-mechanical LE and the light-guiding optical component LG are usually connected in an adhesive manner. The light-guiding optical component LG of the present invention has a thicker thickness, that is, a larger adhesive area. In this case Lower, adhered parts are less likely to break or separate.

Although the present invention has specifically described the structure of the light-guiding optical assembly of the present invention with the above-mentioned embodiments, those skilled in the art to which the present invention pertains should understand that, without violating the technical principle and spirit of the present invention, Modifications and changes are made to the embodiments. Therefore, the protection scope of the present utility model should be as described in the claims.

Claims (8)

1. A light-guiding optical assembly, characterized in that, comprising: A transparent light guide body, comprising a side surface facing the first direction, a first surface and a second surface adjacent to the side surface and facing each other, the transparent light guide body further comprising: A first inclined surface is arranged inside the transparent light guide body and extends from the first surface to the second surface, the first inclined surface and the first surface form a first angle, and the first inclined surface The geometric center of an inclined surface is a first distance from the geometric center of the side surface; and A second inclined surface, disposed inside the transparent light guide body, is located on the other side of the first inclined surface facing the side surface, and the second inclined surface extends from the first surface to the second inclined surface a surface that forms a second angle with the first surface, and the geometric center of the second inclined surface is separated from the geometric center of the side surface by a second distance; Wherein, when the input light enters the transparent light guide body, the input light reflected by the first inclined surface and the second inclined surface forms an output light and is output by the transparent light guide body. 2. The light directing optical assembly of claim 1, wherein the first angle and the second angle are equal. 3. The light directing optical assembly of claim 1, further comprising: a first reflective layer, disposed on the first inclined surface; and a second reflective layer, disposed on the second inclined surface; Wherein, the reflectivity of the first reflective layer is greater than the reflectivity of the first inclined surface, and the reflectivity of the second reflective layer is greater than the reflectivity of the second inclined surface. 4. The light directing optical assembly of claim 1, further comprising: A third inclined surface, disposed inside the transparent light guide body, is located on the other side of the second inclined surface facing the first inclined surface, and the third inclined surface extends from the first surface to the The second surface, the third inclined surface and the first surface form a third angle, and the geometric center of the third inclined surface is separated from the geometric center of the second inclined surface by a third distance, the second inclined surface The distance is not equal to the third distance. 5. The light directing optical assembly of claim 4, wherein the first angle, the second angle, and the third angle are equal. 6. The light directing optical assembly of claim 4, further comprising: a first reflective layer, disposed on the first inclined surface; a second reflective layer disposed on the second inclined surface; and a third reflective layer, disposed on the third inclined surface; Wherein, the reflectivity of the first reflective layer is greater than the reflectivity of the first inclined surface, the reflectivity of the second reflective layer is greater than the reflectivity of the second inclined surface and the reflection of the third reflective layer The rate is greater than the reflectivity of the third inclined surface. 7. The light guiding optical assembly of claim 6, wherein the reflectivity of the third reflective layer is greater than the reflectivity of the second reflective layer and the reflectivity of the first reflective layer. 8 . The light guide optical assembly according to claim 1 , further comprising a transparent member disposed on the first surface and the second surface of the transparent light guide body and covering the transparent light guide body. 9 . For the first surface and the second surface, the material of the transparent member includes glass plastic or resin.

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