TW201901207A - Light-guide device with optical cutoff edge and corresponding production methods - Google Patents

Abstract

A light-guide device includes a light guiding element (13) with a number of faces, including two parallel faces (26), for guiding light by internal reflection. A transparent optical element (19) has an interface surface for attachment to a coupling surface (14) of the light guiding element, and is configured such that light propagating within the transparent optical element passes through the interface surface and the coupling surface (14) so as to propagate within the light guiding element (13). A non-transparent coating (15) is applied to at least part of one or more faces of the light guiding element (13), defining an edge (17) adjacent to, or overlapping, the coupling surface (14) of the light guiding element (13). A quantity of transparent adhesive is deployed between the coupling surface and the interface surface so as to form an optically transmissive interface. An overspill region (31) of the adhesive extends to, and overlaps, the edge (17).

Description

 Light guiding device with optical cutting edge and corresponding production method thereof  

The present invention relates to a variety of light guiding devices, and more particularly to a light guiding device having a well defined optical cutoff edge and a corresponding method of manufacture thereof.

When fabricating an optical device, it is generally desirable to provide a light directing device having a composite form that is formed with different regions having a plurality of surfaces that are angled to a selected non-linear direction. Examples of such devices related to the present invention include, but are not limited to, the light directing element having a coupled input configuration and the transition regions between the plurality of light directing elements having different lateral dimensions and/or different orientations.

Figures 1A and 1B show two examples of a device comprising a light directing element and a coupled input prism as shown in Figures 3 and 7 of PCT Patent Application Publication No. WO 2015/162611, respectively. Referring to the original reference numerals in these figures, each of these devices has a light guiding element 20 having first and second parallel faces 26 and a coupling prism 44, 54 for attachment The light guiding element 20 is provided to provide a suitable angled input surface such that light can be directed to the normal to the surfaces 46, 58 of the prism and then enter the light guide at a desired angle for internal reflection at the surface 26 at the light guide Passing light inside.

The invention is a light guiding device and a corresponding production method thereof.

According to the teachings of the embodiments of the present invention, there is provided an apparatus comprising: (a) a light guiding element having a plurality of faces, the faces comprising a first parallel face and a second parallel face, the light guiding element being Configuring to direct light at the first and second parallel faces by internal reflection, one of the faces providing a coupling surface; (b) a transparent optical element having an interface surface for attaching to the a coupling surface, the transparent optical element being configured to pass light propagating within the transparent optical element through the interface surface and the coupling surface for propagation in the light guiding element; (c) an opaque coating applied to the At least a portion of at least one of the plurality of faces of the light directing element, the coating defines an edge abutting or overlapping the coupling surface of the light guiding element; and (d) a quantity of transparent adhesive, configured Between the coupling surface and the interface surface, an optically transmissive interface is formed, the adhesive extending to and overlapping the edge.

According to another feature of an embodiment of the present invention, the coupling surface is disposed on one of the first parallel surface and the second parallel surface.

According to another feature of an embodiment of the invention, the coating extends between the coupling surface and the interface surface.

According to another feature of an embodiment of the invention, the coupling surface is inclined relative to the first and second parallel faces.

According to another feature of an embodiment of the present invention, the coupling surface is in contact with the first parallel surface at a bottom edge, and wherein the edge does not overlap the bottom edge.

According to another feature of an embodiment of the invention, the adhesive is filled in a recess formed between the bottom edge and the interface surface.

According to another feature of an embodiment of the invention, the coupling surface is inclined obliquely with respect to the first and second parallel faces.

According to another feature of an embodiment of the invention, the coupling surface is perpendicular to the first and second parallel faces.

According to another feature of an embodiment of the invention, the interface surface is larger than the coupling surface.

According to another feature of an embodiment of the invention, the coating is a metallic coating.

According to another feature of an embodiment of the invention, the coating is a dielectric coating.

According to another feature of an embodiment of the invention, the transparent optical element is a coupling prism configured to provide an input surface oriented for inputting light into the light guiding element.

According to another feature of an embodiment of the invention, the edge defines an optically truncated edge for directing light through the transparent optical element into the light guiding element.

According to the teachings of the embodiments of the present invention, there is provided an apparatus comprising: (a) a light guiding element having a plurality of faces, the faces comprising a first parallel face and a second parallel face, the light guiding element being Configuring to direct light at the first and second parallel faces by internal reflection, one of the faces providing a coupling surface; (b) a coupling raft having an interface surface for attaching to the a coupling surface having an input surface for inputting light into the light guiding element; and (c) an opaque coating applied to the coupling surface of the light guiding element and at the light guiding element and the coupling edge Extending between the mirrors, the coating defines an optically truncated edge for directing light through the coupling aperture into the light guiding element.

According to another feature of an embodiment of the invention, the coupling prism is attached to the coupling surface of the light guiding element and no adhesive is used.

According to the teachings of the embodiments of the present invention, there is provided an apparatus comprising: (a) a light guiding element having a plurality of faces, the faces comprising a first parallel face and a second parallel face, the light guiding element being Configuring to direct light at the first and second parallel faces by internal reflection, one of the faces providing a coupling surface; (b) a coupling raft having an interface surface for attaching to the a coupling surface, and having an input surface for inputting light into the light guiding element; and (c) a quantity of transparent adhesive disposed between the coupling surface and the interface surface to form an optically transmissive interface, A portion of the quantitative adhesive forms a partial fill of an angled recess between the light guiding element and the coupling prism; wherein an air gap is along the guide under the partial fill One of the faces of the optical element extends, the air gap terminating at an edge within the adhesive to define an optically cut edge abutting the coupling surface of the light guiding element.

In accordance with an embodiment of the present invention, a method for fabricating an optical component is provided, comprising: (a) providing a light guiding element having a plurality of faces, the faces comprising a first parallel face And a second parallel surface, the light guiding element is configured to guide light by internal reflection at the first and second parallel faces; (b) applying a coating to the faces of the light guiding element At least a portion of at least one face; (c) grinding the light guiding element along a plane intersecting the coating to simultaneously form a coupling surface of the light guiding element and an edge of the coating; and (d) Bonding an interface surface of a transparent optical element to the coupling surface, the transparent optical element being configured such that light propagating within the transparent optical element passes through the interface surface and the coupling surface to propagate within the light guiding element; Wherein the bonding step is performed by applying a quantity of a transparent adhesive between the coupling surface and the interface surface, the quantitative adhesive being coated such that the coupling surface and the interface surface are pressed together When, a superfluous Overlap the transparent adhesive to the edge of the coating.

According to another feature of an embodiment of the invention, the coating is an opaque coating such that the edge defines an optically truncated edge.

According to another feature of an embodiment of the present invention, there is provided a further step of selectively removing the coating to leave a cut-off edge through an edge of an air gap formed in the transparent adhesive. The definition is formed.

R11‧‧‧Light

R12‧‧‧Light

R13‧‧‧Light

R14‧‧‧Light

R15‧‧‧Light

R21‧‧‧Light

R22‧‧‧Light

R23‧‧‧Light

R24‧‧‧Light

R25‧‧‧Light

R31‧‧‧Light

R32‧‧‧Light

R33‧‧‧Light

R34‧‧‧Light

R35‧‧‧Light

10‧‧‧Light guiding elements

13‧‧‧Transparent optical components

14‧‧‧Coupling surface

15‧‧‧Coating

17‧‧‧ edge

18‧‧‧ input surface

19‧‧‧Transparent optical components

20‧‧‧Light guiding elements

26‧‧‧ parallel faces

31‧‧‧ overflow area

32‧‧‧ edge

34‧‧‧Air gap

37‧‧‧Area

44‧‧‧Coupling prism

46‧‧‧ surface

54‧‧‧Coupling prism

58‧‧‧ surface

2110‧‧‧colloid

2705‧‧‧Bottom outer surface

2710‧‧‧Top outer surface

40f1‧‧‧Protective coating

40f2‧‧‧Protective coating

40f3‧‧‧Protective coating

40f4‧‧‧Protective coating

80f1‧‧‧ coating

80f2‧‧‧ coating

80f3‧‧‧Protective coating

The invention will be described herein by way of example only, with reference to the accompanying drawings, in which: FIG. 1A and FIG. 1B are respectively described in the third and seventh figures of PCT Patent Application Publication No. WO 2015/162611, respectively. Advantageously applied to the light guiding device of the present invention; FIG. 1C is a schematic isometric view of the light guiding device according to an aspect of the present invention, wherein the text of the present invention can also be advantageously applied; 2A, 2B 2 and FIG. 2C are schematic enlarged cross-sectional partial views showing a joint region of two transparent optical elements, respectively showing that the joint has no adhesive, an adhesive, and a protective layer is covered by the adhesive, according to an embodiment of the present invention. The views show various ray paths for each case; FIGS. 3A-3C show schematic isometric views of a series of stages during manufacture of the light guiding device, respectively showing light guiding elements, in accordance with an embodiment of the present invention After coating the coating, after grinding the coupling surface, and after coupling of the coupling input prisms; Figure 3D shows a schematic isometric view of a light guiding element, in accordance with some embodiments of the present invention After the production sequence coats the coating with the preformed edges; FIGS. 4A and 4B show schematic side views of various stages of the manufacturing process in various stages of the manufacturing process, respectively showing the light guiding elements after coating And after the coupling of the coupled input prisms; FIG. 4C is a view similar to FIG. 4B, showing the overall optical effect of the device produced by the manufacturing processes of FIGS. 4A and 4B; FIGS. 5A to 5C A schematic side view of a stage in a production process of a modified embodiment of the apparatus of FIG. 4C; FIGS. 6A to 6C are diagrams showing stages of production of a light guiding apparatus according to another embodiment of the present invention, etc. An angular view, respectively, showing the light guiding element after coating the coating, after grinding the coupling surface, and after coupling of the coupling input prism; Figure 6D is a view similar to Figure 6C, showing from Figure 6A to Figure 6C The overall optical effect of the device produced by the manufacturing process of the drawing; Figure 7A is a view similar to Figure 2C, showing another variant embodiment of the invention, according to which the coating is removed to leave an air gap Fig. 7B is a view similar to Fig. 6D, showing an embodiment using an air gap device according to Fig. 7A; Fig. 8A is a view showing light guiding of another modified embodiment of the device of Figs. 1C and 3C An isometric view of the device, which is a construction and operation in accordance with one embodiment of the present invention; and FIG. 8B shows a schematic level cross-sectional view of the device adjacent to the light directing element through the device of FIG. 8A, shown along Propagation of the input image aperture of the light guiding element; and FIG. 9 is a schematic end view showing a light guiding device formed by superposition of two light guiding elements in accordance with an embodiment of the teachings of the present invention.

The invention is a light guiding device and a corresponding production method thereof.

The principle and operation of the light guiding device according to the present invention can be better understood with reference to the drawings and the accompanying description.

By way of illustration, the present invention is directed to a series of situations in which two transparent elements are joined, and particularly, but not exclusively, the outer surfaces of the two elements meet at an angle or a step. The bonding between the two transparent elements of an optical system presents some practical challenges. First, the edges of the block of transparent material are not perfectly sharp edges and are modified (twisted) by a certain radius of curvature, often with some gaps or other defects. The extent of this arc usually depends on the nature of the material and the type of equipment used. Fig. 2A shows a schematic partial cross-sectional enlarged view of a joint region of two transparent optical members 13 and 19, wherein one edge 32 of the member 13 is ground to have a radius of curvature. This radius of curvature results in various scattering effects that reduce the overall quality of the optical device. Therefore, when the light rays R11 and R13 are not scattered from the optical element 19 to the optical element 13 and propagate along the optical element 13 as expected, and the light ray R15 is excluded from the optical element 13, the light rays R12 and R14 and various kinds of surfaces The interaction of the intermediate angles due to the edge 32 of the arc causes the scattered light to be at multiple angles rather than corresponding to the design of the device, thereby reducing the signal to noise ratio of the overall device.

Another problem arises by using an optical adhesive, as shown in Figure 2B. In order to ensure uniform optical performance at the interface, a sufficient amount of optical adhesive is interposed between the opposing surfaces, and after pressing the opposing surfaces together, the entire area of the opposing surface to be joined is covered by the adhesive. This typically results in some spilled excess adhesive at the end of the surface to be joined, forming an overflow region 31, which may be of any size and uncontrolled shape. Since the adhesive is a transparent adhesive and generally also matches the refractive index of the transparent optical element, the overflow region 31 defines an optical path for additional light, which may result in scattering and unwanted multiple angles of light in the optical Propagation within element 13. Thus, in the embodiment shown here, the rays R23 and R24 are not scattered from the optical element 19 to the optical element 13 and propagate along the optical element 13, and the light rays R22 escape without reaching the optical element 13. However, the ray rays R21 and R25 and any angular surfaces of the overflow region 31 of the adhesive interact with each other, resulting in scattering of the light at multiple angles rather than corresponding to the design of the device, thereby reducing the signal to noise ratio of the overall device.

According to an aspect of the invention, as shown in FIG. 2C, there is provided an optical device or apparatus comprising two transparent optical elements, typically a light guiding element 13, having a plurality of faces including a first parallel surface and a The two parallel faces 26 are such that light can be guided within the element 13 by internal reflections on the first and second parallel faces 26. The second transparent optical element 19 has an interface surface for attachment to a coupling surface of the light guiding element 13. A non-transparent (opaque) coating 15 is applied to at least a portion of at least one face of the plurality of faces of light directing element 13, in this case one of the parallel faces 26. The coating 15 is preferably selected to provide (or maintain) reflective properties for reflection within the surface of the light guiding element 13, and preferably defines an edge 17 that is adjacent to, or overlaps with, described in some cases below, On the coupling surface of the light guiding element 13. A quantity of transparent adhesive is disposed between the coupling surface and the interface surface to form an optically transmissive interface that forms an overflow region 31 that extends to and partially overlaps the edge 17.

As shown in Figure 2C, the presence of coating 15 in accordance with an exemplary embodiment significantly enhances the optical properties of the device. First, since the coating 15 is present on the surface of the light guiding member 13, the adhesive of the overflow region 31 does not damage the internal reflection characteristics of the light guiding member 13, so that the light ray R31 is internally reflected inside the light guiding member, and is guided The optical element propagates correctly within the optical element. In addition, the edge 17 is here an optically truncated edge, clearly depicted between the plurality of rays R31, R33 and R34 entering the light guiding element without distortion, and the rays R32 and R35 are excluded. Any stray light is reflected by the irregular surface of the adhesive overflow region 31, such as the light R35, and is exposed to the coating 15 of the outer surface to be excluded from the light guiding member.

The coating 15 can be formed of any material suitable for coating on the surface of an optical component and provides the desired optical blocking properties of the transparent optical component and provides internal reflective properties. Embodiments include, but are not limited to, various metal coatings and various dielectric coatings. In a particularly preferred but non-limiting embodiment, a silver coating with a thin sealing protective layer to prevent oxidation has been known to be particularly effective and suitable for such applications.

The invention is applicable to a wide range of applications in which two transparent optical elements are joined together. A particularly important subset of applications are directed to means for directing light from another light guiding element or coupling input arrangement 19 into a light guiding element 13. Such an application can employ a number of different attachment geometries to mount the attached optical component 19 to various different surfaces of the light directing element 13, as shown in Figures 1A-1C. In FIG. 1A, a coupling prism is attached to one of a plurality of major parallel surfaces of the light guiding member, while in FIG. 1B, the attached prism is at an oblique angled coupling input surface. At the office. The attachment may also be at an end face perpendicular to the major surface of a light directing element, as shown in the novel structure of Figure 1C, relating to a rectangular light guiding element having two pairs of parallel surfaces. Yet another embodiment of an embodiment of the invention can be found below for each of these geometries.

The sequence of operations for producing an optical device in accordance with the present invention may vary depending on the particular design employed. Figures 3A through 3C illustrate a sequence of production stages, corresponding to a particularly preferred method of one aspect of the invention, but are not limiting. In this case, the production of the optical assembly comprises a step of applying a coating 15 to at least a portion of at least one face of a light guiding member 13, which may be a rectangle having two major parallel faces ( a light guiding element comprising a square shape having two pairs of parallel faces for guiding light through the quadruple internal reflection, as shown in FIG. 3A, according to a particularly preferred sequence shown here, the light guiding element 13 along with the coating A plane intersecting the layers is ground to simultaneously form an end coupling surface 14 of the coating 15 and an edge 17, as shown in Figure 3B. An interface surface of a transparent optical element, such as a coupling input 19, is then bonded to the coupling surface 14 such that light propagating within the transparent optical element can pass through the interface surface and the coupling surface to propagate within the light guiding element . The bonding with the light guiding element 13 is performed by applying a certain amount of a transparent adhesive between the coupling surface and the interface surface. The adhesive is applied such that when the coupling surface and the interface surface are pressed together, the excess portion of the transparent adhesive overlaps the edge 17 of the coating 15 to produce a final result similar to that described above with reference to Figure 2C. The coating prevents the adhesive from adversely affecting the characteristics of the light guiding element, wherein the edge 17 provides a defined optical cut-off edge and defines which light beam enters and does not enter the light guiding element. This method may be advantageous for coupling the surface at any desired angle, including, for example, the orthogonally coupled surface of Figure 1C and the obliquely coupled surfaces such as Figures 3B and 3C.

It is considered advantageous to simultaneously form the coupling surface 14 and the edge 17 in a grinding/polishing process because it ensures the correct position of the edge 17 relative to the coupling surface 14, typically just beyond any non-planar surface that occurs at the end of the coupling surface. The edge effect, as shown in Figure 2C, avoids the need to form a sharp edge in the coating process, as a result of this process, the coupling surface 14 and one of the plurality of parallel faces of the light guiding element are A bottom edge meets and the edge 17 of the coating is in a non-overlapping relationship with the bottom edge. As used herein, "bottom edge" refers to the entire area where an angular transition from the plane occurs.

Alternatively, as shown in the example of Figure 3D, a region of the coating 15 can be applied to a light directing element 13 to define an edge 17 during coating of the coating. The technique of the present invention for coating the coating, in particular for the selective coating of a layer to form a well defined edge, is known in the art and can be selected depending on the type of coating used and Corresponding coating techniques, for example, a protected silver coating or a dielectric coating can be applied by conventional deposition techniques such as sputtering or wet chemical deposition, and the shape of the coating can be varied by various traditions. Techniques include, but are not limited to, lithography that defines a patterned photoresist, and mechanical reticle, such as by using an adhesive tape. The coating of the coating is particularly useful during the coating process to define a well defined edge, in which the other transparent optical element is bonded to the coating of the light guiding element on one of a plurality of major parallel surfaces, for example in the first In the structure of Figure 1A. An embodiment of such an application will be described below and with reference to Figures 4A through 4C.

The coating of the present invention may be applied to one or more surfaces of one or both optical elements to be bonded, and may be applied to the entire surface(s) of the surface or, more preferably, only (multiple a portion of the surface that is significantly close to the bonding region, which will be required to protect the properties of the adhesive, and thus, in many embodiments, the total area of the coating in the final assembly device is less than half of the total surface area, at some In some cases, it is smaller than the total area of the bonding surfaces.

In some applications, it may be sufficient for the coating to be applied only on a subset of one or more of the faces. For example, where two components are to be coupled such that certain surfaces will be flush after coupling, it is possible to effectively remove excess adhesive after bonding, and by further polishing steps, this step effectively enables the two components to A total plane re-surfaced.

Referring now to Figures 4A through 4C, one embodiment of the present invention is illustrated, the coupling surface being provided on one of a plurality of major parallel faces defining a light guide. In this case, the coating 15 is advantageously coated to define the edge 17, most preferably a position that overlaps after attachment by the transparent optical element 19 (Fig. 4B). After attachment of the transparent optical element 19, the coating is seen to extend between the coupling surface and the interface surface. Therefore, any overflow region 31 of the adhesive and the bottom edge of the coupling jaw 19 fall outside of the optical cut-off edge 17, such that the adhesive overflows and any defects of the edge of the coupling jaw are not to the device. Optical properties cause adverse effects.

Figure 4C schematically shows the overall optical characteristics of the assembled assembly. As shown in some other particularly preferred embodiments herein, the transparent optical element 19 is a coupling aperture configured to provide an input surface 18 for inputting light into the light guiding element 13. In particular, for a light guiding element, which is an embodiment of a component of a system in which light propagates within a given range of angles within the element, the input surface 18 may advantageously be substantially perpendicular to the input light. Direction, thereby minimizing distortion. In addition, using edge 17 as an optical cutoff, this configuration can be used to "fill" the light guiding element with light from an image, with a slightly oversized image aperture being "trimmed" through an optically truncated edge. It is ensured that the image (and its reflected conjugate image) appears at all locations within the light guiding element. For this purpose, the edge 17 need not necessarily be a straight edge, but should be an edge of any desired shape that is clearly defined. A variety of devices for filling a light-guiding element with an image are described in PCT Patent Application Publication No. WO 2015/162611, the disclosure of which is incorporated herein by reference. PCT/IL2017/051028 (not yet disclosed at the time of the filing date of the present application) is used for a light guiding element having two pairs of parallel faces. In each of these configurations, the optical truncation edge for trimming the input coupling image can advantageously be implemented in accordance with the teachings of the present invention. It should be noted that the thickness of the trimmed edge is defined by the thickness of the coating, which is a thin coating, and produces minimal scattering.

5A to 5C show an improved production sequence and final form of an optical assembly similar to the functions of FIGS. 4A to 4C, but in which the optical shape of the geometry is enhanced. In this case, as shown in Fig. 4A, the light guiding element 13 is coated by the coating 15. In the next step (Fig. 5B), a rectangular crucible 19 is glued to the main parallel faces of the light guiding member 13, and partially covers the coating 15. The use of a rectangle during assembly facilitates the effective press-fitting of the crucible with the light directing element for better bonding. The iridium and light guiding elements are bonded and then polished along the dashed lines to enhance the geometry of the device, as shown in Figure 5C.

Incidentally, although the primary description is directed to the optical elements in the device being bonded by the use of optical adhesives, it should be noted that certain embodiments of the present invention may be practiced without the use of adhesives, with alternatives Adhesion technology is used. The structures of FIGS. 4A-4C and 5A-5C are suitable for various embodiments of such embodiments, wherein the coupling surface 13 of the light guiding element and the interface surface 19 of the transparent optical element are carefully A high degree of planarity is prepared and then joined by a glueless contact ("direct bonding") by bringing the surfaces into direct contact, in which case there is no problem of adhesive spillage. However, the technique of providing a coating with an optically truncated edge extending between the components ensures high quality optical truncation without being affected by any defects in the edges of the coupled turns.

Referring now to Figures 6A through 6D, these illustrations illustrate an exemplary non-limiting process for practicing the invention in the context of a geometry similar to Figure 1B. In such an embodiment, as shown in Fig. 6A, the light guiding element 13 is first coated with a coating 15. The end of the light guiding element is then polished to form the coupling surface, and at the same time the coating area is shortened, thereby producing a trimming edge 17, as shown in Fig. 6B. In Fig. 6C, the crucible 19 is bonded to the coupling surface of the light guiding element 13 with any adhesive overflow 31 covering the edge 17 and a portion of the coating 15. In this case, optionally, the interface surface of the crucible 19 may advantageously be larger than the coupling surface of the light guiding element. Figure 6D schematically illustrates the assembled overall optical structure in which the edge 17 provides an optical cutoff and the optical properties are insensitive to defects in the angular edges of the component.

Referring now to Figures 7A and 7B, an embodiment of another variation of the present invention is shown. In this case, instead of using an opaque coating to define a truncated edge, a removable coating 15 is used to protect the surface of the light guiding element during coating of the adhesive and to define a truncated edge 17. After the bonding is completed and the adhesive has cured, the coating is selectively removed leaving a truncated edge defined by an edge of an air gap 34 formed in the transparent adhesive.

In this case, the coating/coating does not need to have any particular optical requirements and is only present when the adhesive is applied to attach the coupling input port 19. The air gap 34 is created after the material of the layer, such as photoresist or wax, has been removed. The characteristics of such configuration optics include various rays that behave similarly to the light shown in Figure 2C, except that the reflection of light R21 is now through total internal reflection (TIR) of the light guiding element (rather than layer reflection) and The reflection of R25 is through the TIR within the adhesive (rather than an outer surface of the coating). The trimming edge 17 is now determined by the edge of the air gap and the subsequent optical path is continuous. The overall optical properties of the device are shown schematically in Figure 7B.

The invention may be practiced in the context of a combination of optical elements at the surface in any direction, including at a plurality of coupling surfaces that are perpendicular to an direction of extension of a light directing element, as shown in Figure 1C. As described above, the present invention is also applicable to a light guiding element having two pairs of parallel faces in which light is propagated by quadruple reflection, which is called a "two-dimensional (2D) waveguide."

In some cases, a protective layer coating can be used to advantage on selected surfaces of the two components to be bonded. Therefore, in FIGS. 8A and 8B, a protective coating may be preferably applied on both sides of the light guiding element 13, which may be between the crucible 13 and the light guiding element 13 in order to reduce unevenness. The discontinuity of the region (region 37 in Fig. 8A) is caused. The coating is shown on both sides of the light guiding element 13 as 80f1 and 80f2. By introducing a protective coating around all ends of the waveguide element 13 (including 80f1, 80f2 and the other two orthogonal sides), the guiding of the waveguide will be protected from glue spillage or edge non-uniformity from all sides. Impact. If the step between the prism 19 and the light guiding element 13 near 80f2 is small (or absent), it is also advantageous to protect the reflection of the prism 19 from any colloidal spillage by the protective coating 80f3.

Referring finally to Figure 9, although primarily shown in the context of a coupled output prism attached to a light directing element, the invention is equally applicable to other applications, such as a first light directing element (or " The waveguide") feeds into the other. Fig. 9 shows an embodiment in which a rectangular (two-dimensional (2D)) light guiding element 10 is fed into a plate type (one-dimensional (1D)) light guiding element 20. This configuration corresponds to one of a plurality of such options described in the aforementioned co-pending PCT Patent Application No. PCT/IL2017/051028, which is not hereby incorporated by reference in its entirety, and the present application is equally applicable to various variants Embodiments, with or without a coupling prism, as described herein.

The waveguide 10 is slightly larger than the waveguide 20 in order to be able to completely illuminate (fill) the waveguide 20. The colloid 2110 can overflow either or both of the waveguides 20 and 10. A particularly preferred embodiment of the invention provides that the protective coating is on both waveguides as shown at 40f1, 40f2, 40f3 and 40f4.

The scope of the appended patent application does not contain multiple sub-scopes, which are only intended to comply with the multiple sub-subjects of the form requirements of the jurisdiction. It should be noted that all possible combinations of features implied by the multiple appendices of the claimed patent are explicitly contemplated and should be considered as part of the present invention.

It is to be understood that the above description is by way of example only, and that many other embodiments are also within the scope of the invention as defined in the appended claims.

Claims (19)

 A device comprising: (a) a light guiding element having a plurality of faces, the faces comprising a first parallel face and a second parallel face, the light guiding element being configured for the first and second parallel The surface is guided by internal reflections, one of the faces providing a coupling surface; (b) a transparent optical element having an interface surface for attachment to the coupling surface, the transparent optical element being configured to Light propagating within the transparent optical element passes through the interface surface and the coupling surface to propagate in the light guiding element; (c) an opaque coating applied to at least one of the plurality of faces of the light guiding element At least a portion of a face, the coating defines an edge abutting or overlapping the coupling surface of the light guiding element; and (d) a quantity of transparent adhesive disposed between the coupling surface and the interface surface, To form an optically transmissive interface, the adhesive extends to and overlaps the edge.    The device of claim 1, wherein the coupling surface is disposed on one of the first parallel surface and the second parallel surface.    The device of claim 2, wherein the coating extends between the coupling surface and the interface surface.    The device of claim 1, wherein the coupling surface is inclined with respect to the first and second parallel faces.    The device of claim 4, wherein the coupling surface is in contact with the first parallel surface at a bottom edge, and wherein the edge does not overlap the bottom edge.    The device of claim 5, wherein the adhesive is filled in a recess formed between the bottom edge and the interface surface.    The device of claim 4, wherein the coupling surface is inclined obliquely with respect to the first and second parallel faces.    The device of claim 4, wherein the coupling surface is perpendicular to the first and second parallel faces.    The device of claim 1, wherein the interface surface is larger than the coupling surface.    The device of claim 1, wherein the coating is a metal coating.    The device of claim 1, wherein the coating is a dielectric coating.    The device of claim 1, wherein the transparent optical element is a coupling prism configured to provide an input surface oriented for inputting light into the light guiding element.    The device of claim 1, wherein the edge defines an optically truncated edge for directing light through the transparent optical element to the light guiding element.    A device comprising: (a) a light guiding element having a plurality of faces, the faces comprising a first parallel face and a second parallel face, the light guiding element being configured for the first and second parallel The surface is guided by internal reflections, one of the faces providing a coupling surface; (b) a coupling jaw having an interface surface for attachment to the coupling surface and having an input surface for Light is input into the light guiding element; and (c) an opaque coating is applied to the coupling surface of the light guiding element and extends between the light guiding element and the coupling element, the coating defining an optical The truncated edge is used to allow light passing through the coupling aperture to enter the light guiding element.    The device of claim 14, wherein the coupling prism is attached to the coupling surface of the light guiding element and no adhesive is used.    A device comprising: (a) a light guiding element having a plurality of faces, the faces comprising a first parallel face and a second parallel face, the light guiding element being configured for the first and second parallel The surface is guided by internal reflections, one of the faces providing a coupling surface; (b) a coupling jaw having an interface surface for attachment to the coupling surface and having an input surface for Light is input into the light guiding element; and (c) a quantity of transparent adhesive disposed between the coupling surface and the interface surface to form an optically transmissive interface, a portion of the quantitative adhesive forming a a partial filling of the angled recess, the angled recess between the light guiding element and the coupling prism; wherein an air gap extends under the partial filling along one of the faces of the light guiding element, The air gap terminates at an edge within the adhesive to define an optical truncation edge adjacent the coupling surface of the light guiding element.    A method for manufacturing an optical component, comprising: (a) providing a light guiding component, the light guiding component having a plurality of faces, the faces comprising a first parallel face and a second parallel face, the light guiding component Configuring to direct light by internal reflection at the first and second parallel faces; (b) applying a coating to at least a portion of at least one of the faces of the light guiding element; (c) Polishing the light guiding element along a plane intersecting the coating to simultaneously form a coupling surface of the light guiding element and an edge of the coating; and (d) bonding an interface surface of a transparent optical element to The coupling surface, the transparent optical element being configured such that light propagating within the transparent optical element passes through the interface surface and the coupling surface to propagate within the light guiding element; wherein the step of bonding is by passing a certain amount A transparent adhesive is applied between the coupling surface and the interface surface, the quantitative adhesive being coated such that when the coupling surface and the interface surface are pressed together, an excess amount of the transparent adhesive Overlaid on the coating edge.    The method of claim 17, wherein the coating is an opaque coating such that the edge defines an optically truncated edge.    The method of claim 17, further comprising the step of: selectively removing the coating to leave a cut-off edge, the cut-off edge being an air gap formed in the transparent adhesive The edge is defined by the definition.