Waveguide device for data glasses, data glasses and method for operating a waveguide device

Abstract

The invention relates to a waveguide device (104) for data glasses, wherein the waveguide device (104) has a waveguide (200) with a coupling-in region (202) for coupling in a light beam (204), a coupling-out region (206) for coupling out a light bundle (208), and a guide region (210) which is arranged between the coupling-in region (202) and the coupling-out region (206) and has a first reflection portion (212) and a second reflection portion (214), wherein the first reflection portion (212) is shaped to generate from the light beam (204) a first beam (216) and a second beam (218) for the light bundle (208) and to deflect same in the direction of the second reflection portion (214).

Description

[0001] Description

[0002] title

[0003] Wave guide device for data glasses, data glasses and method for operating a wave guide device

[0004] State of the art

[0005] The invention relates to a waveguide device for smart glasses, smart glasses, and a method for operating a waveguide device according to the preamble of the independent claims. The present invention also relates to a computer program.

[0006] Augmented Reality (AR) glasses are glasses that allow the user to see both the real environment and virtually superimposed image content simultaneously. This technology requires a "combiner," a component that transmits light from the environment to the eye (real image) and overlays or "combines" it with the light from the artificially generated image content (augmented image).

[0007] Disclosure of the invention

[0008] Against this background, the approach presented here introduces an improved waveguide device for smart glasses, an improved smart glasses, and an improved method for operating a waveguide device according to the main claims. The measures listed in the dependent claims enable advantageous further developments and improvements of the device specified in the independent claim. The presented approach makes it possible to cover the largest possible area of ​​a field of view, i.e., an eyebox, with a small beam diameter in conjunction with optical systems. Advantageously, several beams can strike the user's eye at any given time to ensure good homogeneity of brightness.

[0009] Advantageously, the presented approach allows for dense light extraction, which can be designed to be denser than the diameter of an eye's pupil, ensuring that light enters the eye at every point within the eyebox. This approach also allows the waveguide to be of arbitrary thickness.

[0010] A waveguide device for data glasses is presented, wherein the waveguide device comprises a waveguide with an input region for coupling a light beam, an output region for coupling out a light beam, and a guide section arranged between the input region and the output region, comprising a first reflection section and a second reflection section. The first reflection section is shaped to generate a first beam and a second beam from the light beam for the light beam and to deflect them towards the second reflection section.

[0011] The waveguide device can advantageously be used in conjunction with augmented reality (AR) or, for example, virtual reality (VR), so that an entire eyebox—that is, the field of vision for a user of the smart glasses—can be illuminated. This eyebox can advantageously be located in the output area. For this purpose, the waveguide device includes the waveguide, which can be positioned, for example, within the area of ​​a lens of the smart glasses. Advantageously, the waveguide device can integrate a displayed image into the user's field of vision, allowing them to see both their surroundings and the displayed image. The reflective sections can be arranged, for example, on two opposite sides of the waveguide. Advantageously, the manufacturing costs of the waveguide device can be reduced while simultaneously expanding the user's field of vision.According to one embodiment, the first reflection section can comprise a first wall section of the waveguide and a replication device. The first wall section can be shaped to generate the first beam from the light beam and deflect it towards the second reflection section. The replication device can be shaped to generate the second beam from the light beam and deflect it towards the second reflection section. Advantageously, the use of the replication device allows for the generation of multiple replications of the light beam, thus creating a dense network of output points within the eyebox. The replication device can, for example, be implemented as a planar element. Advantageously, the replication device can be transparent or semi-transparent.Advantageously, the so-called jump length can be shortened by using the replication device. This means that, by using the replication device, the beam diameter of a single laser beam is advantageously sufficient to cover the entire eyebox.

[0012] The replication device can be located outside the waveguide on the first wall section. Advantageously, the replication device can be arranged as a layer on the waveguide. Advantageously, the fabrication of the waveguide device can be simplified.

[0013] Furthermore, the waveguide can have a first side and a second side opposite the first. The replication device can have a transition surface facing the second side and a reflective surface facing away from the waveguide, whereby the light beam can enter the waveguide at the first side in the coupling region and be reflected at the second side as the first beam in the direction of the second reflective section. The light beam can exit the waveguide at the second side and pass through the transition surface as the second beam. The second beam can be reflected at the reflective surface in the direction of the second reflective section. This means that the second beam can, for example, be split or enter the waveguide. This can be related, for example, to the length of the replication device.The sides and surfaces can advantageously be arranged parallel to each other. More precisely, the transition surface can advantageously be directly adjacent to or arranged on the second side of the waveguide.

[0014] According to one embodiment, the replication device can be partially mirrored at the interface or have a different refractive index than the waveguide. Advantageously, reflection of the light beam can occur at the interface due to Fresnel coefficients. The replication device advantageously allows for a wider selection of waveguide materials, thereby reducing costs.

[0015] Furthermore, the replication device can be arranged within the waveguide opposite the first wall section. Advantageously, the replication device can be integrated into the waveguide.

[0016] According to one embodiment, the replication device can be configured as a film, a glass sheet, a metal layer, and additionally or alternatively as a dielectric mirror. The replication device can advantageously be thin and additionally or alternatively partially transparent. Alternatively, the replication device can comprise a plurality of partially mirrored layers, wherein the individual layers within the plurality of partially mirrored layers can have different thicknesses.

[0017] Furthermore, the second reflective section can comprise a second wall section of the waveguide, wherein the second wall section can be shaped to deflect the first and second beams towards a third reflective section. The two wall sections can, for example, be arranged parallel to each other. The multiple reflective sections advantageously allow the beams generated from the light beam to be guided through the entire length of the waveguide. This advantageously expands the field of view for the smart glasses. According to one embodiment, the third reflective section can comprise a third wall section of the waveguide, wherein the third wall section can be shaped to deflect at least a portion of the first beam and at least a portion of the second beam towards a fourth reflective section.Advantageously, the number of reflection sections can depend on the length of the waveguide.

[0018] The third wall section can be shaped to generate a first partial beam from the first beam and a second partial beam from the second beam, and deflect them towards the fourth reflection section. Furthermore, another replication device can be shaped to generate a third partial beam from the first beam and a fourth partial beam from the second beam, and deflect them towards the fourth reflection section. For example, several replication devices can be used as part of the waveguide assembly. This allows the beams to be advantageously multiplied. This can also be advantageously implemented for different types of smart glasses, for example, by varying the number of devices.

[0019] The replication unit and the subsequent replication unit can be formed by a single, continuous reflective element. Advantageously, the replication units can together form the reflective element, which can advantageously be a single piece. Advantageously, additional beams can be generated.

[0020] According to one embodiment, the replication device can be configured to generate a second, third, and fourth beam from the light beam and deflect them toward the second reflection section. Advantageously, the beams can together form the light bundle that can be coupled out of the waveguide in the output section. The waveguide device can also be designed as a combiner. The use of the waveguide device advantageously improves robustness against translational tolerances of the eye pupil relative to the eyeglasses. Such tolerances are caused, for example, by manufacturing tolerances of the eyeglasses, different head sizes and shapes, slippage of the eyeglasses during prolonged wear, and eye movements.The waveguide device advantageously allows the entire image to be visible everywhere when the eye is placed within a certain volume, i.e., within the eyebox.

[0021] Furthermore, a data glasses system with a light source for emitting a light beam and a wave guide device in a previously mentioned variant is presented.

[0022] The smart glasses can be used, for example, in conjunction with augmented reality (AR) and additionally or alternatively with virtual reality (VR). Advantageously, the light source can be a laser light source that emits a low-scattering beam. The waveguide device allows further beams to be generated and deflected from the laser beam, so that the laser beam can be used to fully illuminate the field of view of the smart glasses.

[0023] Furthermore, a method for operating a waveguide device in a previously mentioned variant is presented. The method comprises a step of outputting a light beam towards the waveguide, a step of coupling the light beam in the coupling region of the waveguide, a step of generating a first beam and a second beam in the first reflection section of the guide region, and of deflecting the first beam and the second beam towards the second reflection section of the guide region to shape the light beam, and a step of coupling the light beam out in the coupling region of the waveguide.

[0024] The process can advantageously be carried out within a pair of smart glasses, as previously mentioned. This process can be implemented, for example, in software or hardware, or in a hybrid form of both, such as in a control unit, and / or executed by such a unit.

[0025] Examples of the approach presented here are shown in the drawings and explained in more detail in the following description. It shows:

[0026] Fig. 1 shows a schematic representation of an exemplary embodiment of data glasses;

[0027] Fig. 2 shows a schematic representation of an embodiment of a wave guide device;

[0028] Fig. 3 shows a schematic representation of an embodiment of a wave guide device;

[0029] Fig. 4 shows a schematic representation of an embodiment of a wave guide device;

[0030] Fig. 5 shows a schematic representation of an embodiment of a wave guide device;

[0031] Fig. 6 shows a schematic representation of an embodiment of a reflection section; and

[0032] Fig. 7 shows a flowchart of a method according to an exemplary embodiment for operating a wave guide device.

[0033] In the following description of advantageous embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and having a similar effect, thus avoiding a repeated description of these elements. Fig. 1 shows a schematic representation of an embodiment of data glasses 100, which are used, for example, in conjunction with augmented reality (AR) systems. The data glasses 100 have a light source 102 for emitting a light beam and a waveguide 104, as described in more detail in at least one of the following figures. The light source is, for example, designed as a laser, which accordingly emits a laser beam as its light beam.The waveguide device 104 is arranged in the area of ​​a spectacle lens 106, as it deflects the light beam accordingly into a user's field of vision, which at least partially covers an area of ​​the spectacle lens 106. For example, the data glasses 100 also have a control unit 108, which is designed to control the light source 102.

[0034] The data glasses 100, also known as AR glasses, are, in other words, glasses that allow the user to see both the real environment and virtually superimposed image content simultaneously. This technology requires a "combiner," which is implemented as an element that transmits light from the environment to the eye, corresponding to a real image, and overlays or combines it with the light from the artificially generated image content, corresponding to an augmented image. This allows the user to continue seeing their surroundings while also receiving additional information. A typical combiner is a waveguide.

[0035] The spectacle lens 106 contains a flat or curved plate made of a high-refractive-index core material. Light is guided within this core as total internal reflection modes (TIR modes). Various k-vectors (ray directions or angles) can be guided within the core, each propagating back and forth between the front and back of the core with its own lateral jump length (gump length).

[0036] The light source 102 can utilize a combination of lasers and scanner mirrors for image generation. By tilting a mirror, beams are deflected in different directions. After passing through the optics, the beams are displayed to the user at different angles (field of view). The scanner of a two-dimensional image can, for example, consist of a two-dimensionally tiltable mirror or of two separate mirrors, each with a tilting axis. The approach described here is used, according to an exemplary embodiment, in conjunction with a system that constructs the image using a laser scanner.

[0037] Fig. 2 shows a schematic representation of an embodiment of a waveguide device 104, which can be used, for example, for data glasses as described in Fig. 1. The waveguide device 104, which is designed, for example, as a combiner, has a waveguide 200 with an input area 202 for coupling in a light beam 204, an output area 206 for coupling out a light beam 208, and a guide area 210 arranged between the input area 202 and the output area 208, with a first reflection section 212 and a second reflection section 214, wherein the first reflection section 212 is shaped to generate a first beam 216 and a second beam 218 for the light beam 208 from the light beam 204 and to deflect them in the direction of the second reflection section 214.

[0038] For example, the waveguide device 104 has a coupling coupler 220 in the coupling area 202 for coupling the light beam 204 into the waveguide 200 and an uncoupling coupler 222 in the coupling area 206 for coupling out the light beam 208. According to this embodiment, the first reflection section 212 comprises a first wall section 224 of the waveguide 200 and a replication device 226. The first wall section 224 is shaped to generate the first beam 216 from the light beam 204 and deflect it towards the second reflection section 214. Furthermore, the replication device 226 is shaped to generate the second beam 218 from the light beam 204 and also deflect it towards the second reflection section 214.More precisely, one portion, the first beam 216, is reflected directly at a transition from the waveguide 200 to the replication device 226, and another portion of the light beam 204 passes through the replication device 226 to a wall of the replication device 226, where it is deflected and thus reflected as the second beam 218 towards the second reflection section 214. The second reflection section 214 comprises, for example, a second wall section 228 of the waveguide 200. The second wall section 228 is shaped to deflect the first beam 216 and the second beam 218 towards a third reflection section 230.Analogous to the second reflection section 214, the third reflection section 230 according to this embodiment comprises a third wall section 232 of the waveguide 200, wherein the third wall section 232 is shaped to deflect at least a portion of the first beam 216 and at least a portion of the second beam 218 towards a fourth reflection section 234. This means that the beams 216, 218 are guided in a zigzag pattern through the guide section 210 of the waveguide 200 until they are coupled out as the light beam 208 via the output coupling section 206.

[0039] According to this embodiment, the replication device 226 is arranged outside the waveguide 200 on the first wall section 224. Alternatively, the replication device 226 can be arranged inside the waveguide opposite the first wall section 224. Furthermore, the replication device 226 can optionally be designed as a film, a glass plate, a metal layer, and / or a dielectric mirror. The replication device 226 can, for example, be thin and / or partially transparent, or have a plurality of partially mirrored layers, which can be implemented or are implemented with different thicknesses.

[0040] In other words, a semi-transparent reflective element, described here as a replication device 226, generates additional replications on the waveguide 200, thus creating a denser network and couplings in the eyebox. This allows waveguides 200 of any thickness to be used, as even thick waveguides 200 can generate dense replications. For example, an extended angular spectrum in the waveguide 200 is used to expand the field of view.

[0041] The replication device 226 is implemented, for example, as a partially mirrored film applied to the waveguide 200. Alternatively, the replication device 226 is implemented as a partially mirrored thin glass sheet, or the mirroring can be implemented as a thin, partially transparent metal layer or a dielectric mirror. Furthermore, the replication device 226 can be implemented, for example, as a glass sheet or film without surface mirroring, which in this case has a different refractive index than the core, i.e., the waveguide 200. A reflection occurs, for example, due to the Fresnel coefficients at the interface. Additionally or alternatively, the replication device 226 is implemented, for example, as a sandwich of several partially mirrored elements, such as a film stack.For example, a sandwich of several films with a fraction of the core thickness generates a uniform pattern of outflows.

[0042] According to one embodiment, an element of half thickness halves the effective jump length.

[0043] Furthermore, mirrors can be introduced into the core volume as a replication device 226, for example, with the mirrors being partially reflective. It is also possible to change the glass refractive index to that of a dielectric mirror within the core volume, for example, using Schott PTR glass. Alternatively, a mirror can be inscribed into the volume, for example, using a material-modifying laser. In another alternative, the replication device 226 can be implemented as a long mirror element, several gum lengths long, with which the original light beam 204 interacts multiple times, as described, for example, in at least one of Figures 4 to 5. An advantage of this is, for example, the creation of more replicas.

[0044] According to this embodiment, the replication device 226 is designed as a short element, less than or equal to a jump length. Advantages of this include, for example, reduced interference between the replicas. A "gray wedge," meaning an element with variable reflectivity, can improve brightness homogeneity.

[0045] Fig. 3 shows a schematic representation of an embodiment of a

[0046] Shaft guide device 104, which corresponds, for example, to the shaft guide device described in Fig. 2. According to this embodiment, only the guide area 210 is shown, which corresponds to the guide area in Fig. 2.

[0047] This means that, according to this embodiment, the waveguide 200 has a first side 300 and a second side 302 opposite the first side 300, and the replication device 226 has a transition surface 304 facing the second side 302 and a reflective surface 306 facing away from the waveguide 200. As also described in Fig. 2, the light beam 204 enters the waveguide 200 at the first side 300 in the coupling region and is reflected at the second side 302 as the first beam 216 in the direction of the second reflective section 214. At the second side 302, part of the light beam 204 exits the waveguide 200 and emerges as the second beam 218 through the transition surface 304. Subsequently, the second beam 218 is reflected at the reflective surface 306 in the direction of the second reflective section 214.For this purpose, the transition surface 304 is optionally partially mirrored or has a different refractive index than the waveguide 200, so that the reflection of the light beam 204 at the transition surface 304 is caused, for example, by a Fresnel coefficient.

[0048] Fig. 4 shows a schematic representation of an embodiment of a wave guide device 104, which is similar, for example, to the wave guide device described in at least one of Figures 2 to 3. As in Fig. 3, the guide section 210 is shown in this embodiment.

[0049] According to this embodiment, the waveguide device 104 has, in addition to the replication device 226, a further replication device 400 implemented in the same manner, which is arranged in the third reflection section 230.

[0050] As in Fig. 2, the second wall section 228 is shaped to deflect the first beam 216 and the second beam 218 towards the third reflection section 230. According to this embodiment, the third reflection section 230 also includes the third wall section 232, which is shaped to deflect at least a portion of the first beam 216 and at least a portion of the second beam 218 towards a fourth reflection section 234. This means that the beams 216 and 218 are guided in a zigzag pattern through the guide section 210 of the waveguide 200 until they are coupled out as the light beam 208 via the output section 206. More precisely, the third wall section 232 is shaped to generate a first partial beam 402 from the first beam 216 and a second partial beam 404 from the second beam 218 and, for example, to redirect them towards a fourth reflection section.The further replication device 400 is configured to generate a third partial beam 406 from the first beam 216 and a fourth partial beam 408 from the second beam 218 and to deflect them towards the fourth reflection section. Since the first beam 216 and the second beam 218 are guided parallel to each other through the waveguide 200 and therefore have the same angle of incidence, according to this embodiment, the second partial beam 404 and the third partial beam 406 coincide at a further transition surface 410 of the further replication device 400. This depends, for example, on the thickness of the replication devices 226, 400.

[0051] According to this embodiment, a portion of the second beam 218 is reflected at least once at the interface 304 of the replication device 226, so that a third beam 412 and furthermore a fourth beam 414 are generated by splitting the third beam 412 at the interface 304. The fourth partial beam 408 described above therefore coincides with a fifth partial beam 416 of the third beam 412 generated from the second beam 218 in the replication device 226, according to this embodiment.

[0052] This means that the replication device 226 is shaped to generate the second beam 218, the third beam 412 and the fourth beam 414 from the light beam 204 and redirect them towards the second reflection section 214.

[0053] Fig. 5 shows a schematic representation of an embodiment of a waveguide device 104, which is similar, for example, to the waveguide device described in at least one of Figures 2 to 4. As in Fig. 4, the guide section 210 is shown in this embodiment. The replication device 226 is larger, or longer, than the replication device 226 described in Fig. 3 and is thus designed as a single, continuous replication element, so that the light beam 204 can be multiplied. More precisely, the replication device 226 and the further replication device 400 are formed as a single unit by a continuous reflective element 500. The function of the reflective element 500 corresponds to the function of the replication devices 226 and 400, which are described as two separate parts in Fig. 4.

[0054] Fig. 6 shows a schematic representation of an embodiment of a reflection section 600, which can, for example, correspond to or at least resemble the third reflection section described in at least one of Figures 3 to 5. This means that, according to this embodiment, a section of the further reflection device 400, or the reflection element 500, is shown, in which two partial beams 402, 404, 406, 408 are generated from each of the first beam 216 and the second beam 218. More precisely, the first partial beam 402 and the third partial beam 406 are generated from the first beam 216, and the second partial beam 404 and the fourth partial beam 408 are generated from the second beam 218. According to this embodiment, the partial beams 404 and 406 do not coincide, which is related, for example, to the thickness of the replication element 500.

[0055] Fig. 7 shows a flowchart of a method 700 according to an embodiment for operating a waveguide device, as described or at least mentioned, for example, in at least one of Figures 1 to 6. The method 700 comprises a step 702 of outputting a light beam in the direction of the waveguide, a step 704 of coupling the light beam in the coupling region of the waveguide, a step 706 of generating a first beam and a second beam in the first reflection section of the guide region, as well as deflecting the first beam and the second beam towards the second reflection section of the guide region in order to shape the light beam, and a step 708 of coupling the light beam out in the coupling region of the waveguide.

Claims

Claims 1. Waveguide device (104) for data glasses (100), wherein the waveguide device (104) has the following feature: a waveguide (200) with an input area (202) for coupling in a light beam (204), an output area (206) for coupling out a light beam (208) and a guide area (210) arranged between the input area (202) and the output area (206) with a first reflection section (212) and a second reflection section (214), wherein the first reflection section (212) is shaped to generate a first beam (216) and a second beam (218) for the light beam (208) from the light beam (204) and to deflect them in the direction of the second reflection section (214).

2. Waveguide device (104) according to claim 1, wherein the first reflection section (212) comprises a first wall section (224) of the waveguide (200) and a replication device (226), wherein the first wall section (224) is shaped to generate the first beam (216) from the light beam (204) and deflect it towards the second reflection section (214), and wherein the replication device (226) is shaped to generate the second beam (218) from the light beam (204) and deflect it towards the second reflection section (214).

3. Waveguide device (104) according to claim 2, wherein the replication device (226) is arranged outside the waveguide (200) on the first wall section (224).

4. Waveguide device (104) according to one of claims 2 to 3, wherein the waveguide (200) has a first side (300) and a second side (302) opposite the first side (300), and wherein the replication device (226) has a transition surface (304) facing the second side (302) and a reflection surface (306) facing away from the waveguide (200), wherein the light beam (204) enters the waveguide (200) at the first side (300) in the coupling area (202) and is reflected at the second side (302) as the first beam (216) in the direction of the second reflection section (214), wherein the light beam (204) exits the waveguide (200) at the second side (302) and passes through the transition surface (304) as the second beam (218), wherein the second beam (218) is reflected at the reflection surface (306) in the direction of the second reflection section (214).

5. Waveguide device (104) according to claim 4, wherein the replication device (226) is partially mirrored at the transition surface (304) or has a different refractive index than the waveguide (200).

6. Waveguide device (104) according to claim 2, wherein the replication device (226) is arranged within the waveguide (200) opposite the first wall section (224).

7. Waveguide device (104) according to one of claims 2 to 6, wherein the replication device (226) is designed as a film, as a glass sheet, as a metal layer and / or as a dielectric mirror.

8. Waveguide device (104) according to one of the preceding claims, wherein the second reflection section (214) comprises a second wall section (228) of the waveguide (200), wherein the second wall section (228) is shaped to deflect the first beam (216) and the second beam (218) towards a third reflection section (230).

9. Waveguide device (104) according to claim 8, wherein the third reflection section (230) comprises a third wall section (232) of the waveguide (200), wherein the third wall section (232) is shaped to deflect at least a portion of the first beam (216) and at least a portion of the second beam (218) in the direction of a fourth reflection section (234).

10. Waveguide device (104) according to claim 9, wherein the third wall section (232) is formed to generate a first partial beam (402) from the first beam (216) and a second partial beam (404) from the second beam (218) and to redirect them towards the fourth reflection section (234), and wherein a further replication device (400) is formed to generate a third partial beam (406) from the first beam (216) and a fourth partial beam (408) from the second beam (218) and to redirect them towards the fourth reflection section (234).

11. Waveguide device (104) according to claim 10, wherein the replication device (226) and the further replication device (400) are formed by a continuous reflection element (500).

12. Waveguide device (104) according to one of claims 2 to 11, wherein the replication device (226) is configured to generate the second beam (218), a third beam (412) and a fourth beam (414) from the light beam (204) and to deflect them in the direction of the second reflection section (214).

13. Shaft guide device (104) according to one of the preceding claims, wherein the shaft guide device (104) is designed as a combiner.

14. Data glasses (100) with the following features: a light source (102) for emitting a light beam (204); and a wave guide device (104) according to one of the preceding claims.

15. Method (700) for operating a wave guide device (104) according to any one of claims 1 to 13, wherein the method (700) comprises the following steps: Output (702) of a light beam (204) in the direction of the waveguide (200), Coupling (704) of the light beam in the coupling area of ​​the waveguide; Generating (706) a first beam (216) and a second beam (218) in the first reflection section (212) of the guide area (210), and deflecting the first beam (216) and the second beam (218) towards the second reflection section (214) of the guide area (210) to form the light beam (208); and Coupling (708) of the light beam (208) in the coupling area (206) of the waveguide (200).

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