METHOD FOR MANUFACTURING AN OPTICAL ELEMENT

Description

[0001] The present invention relates to a method for manufacturing an optical element comprising a body transparent for a predetermined wavelength range in which an optically effective structure is embedded, with the features of the preamble of claim 1.

[0002] Such an optical element can be used, for example, as a lens for a display device that can be placed on a user's head and generates an image, wherein the optical element can be part of an imaging optic of the display device and the imaging optic projects the generated image in the state of the display device being placed on the user's head in such a way that the user can perceive it as a virtual image.

[0003] There is a growing need to be able to manufacture such an optical element with a buried optically effective structure in large quantities and with high accuracy.

[0004] WO 2011 / 088161 A1 describes microstructured optical films and manufacturing processes for them. US 2014 / 0043850 A1 describes a method for manufacturing an optical element, and JP 2012 068441 A1 describes a method for manufacturing an optical element, wherein the method has the features of the preamble of claim 1.

[0005] It is therefore an object of the invention to provide a method for manufacturing an optical element comprising a transparent body in which an optically effective structure is embedded, which enables the optical element to be manufactured in high quality and in large quantities.

[0006] The invention is defined in claims 1, 13 and 15. Advantageous embodiments are specified in the dependent claims.

[0007] In particular, the optically effective structure can be completely embedded within the transparent body, so that it does not extend to any external surface of the transparent body. Preferably, the optically effective structure is smaller in its dimensions than the dimensions of the transparent body. It can also be said that the optically effective structure is formed only in a portion of the transparent body. The embedded optically effective structure can have a maximum lateral dimension that is smaller than the maximum lateral dimension of the transparent body. In particular, it can be smaller than 50% of the lateral dimension of the transparent body, or even smaller than 40%, 30%, or 20% of the lateral dimension of the transparent body. The optically effective structure is thus preferably embedded within the transparent body but only partially present.

[0008] By performing step c) using casting, the desired accuracy and reproducibility in production can be ensured even in high quantities.

[0009] In the process according to the invention, a protective layer of thermoset material is applied to the optically effective coating by casting after step b) and before step c). The RIM process (Reaction Injection Moulding) can be used for this purpose. For example, two components can be mixed immediately before injection into a mold, allowing the components to react with each other and form a desired chemically cross-linked polymer. The first transparent component is preferably positioned in a suitable mold so that the desired protective layer can be formed.

[0010] The top layer is preferably formed on the entire upper surface of the first transparent sub-body (including any protective layer). The top layer formation step can be carried out, for example, by injection molding. It is also possible to perform the top layer formation step using a RIM process.

[0011] In the inventive method, the first partial body can be formed from a first polymer material and in step c) a second polymer material can be applied to the top surface of the first partial body to apply the cover layer and a chemical bonding of the second polymer material to the first polymer material can be effected.

[0012] The first polymer material can be a thermoplastic and / or a thermosetting material. The second polymer material is a thermoplastic material. Examples of thermoplastic materials that can be used include PMMA (polymethyl methacrylate, e.g., Plexiglas), PA (polyamides, e.g., Trogamid CX), COP (cycloolefin polymers, e.g., Zeonex), PC (polycarbonate, poly(bisphenol-A-carbonate), e.g., Makrolon), LSR (liquid silicone rubber, e.g., Silopren, Elastosil), PSU (polysulfone, e.g., Ultrason), PES (polyethersulfone), and / or PAS (polyarylenesulfone). Examples of thermosetting materials include ADC (allyl diglycyl carbonate, e.g. CR-39), acrylates (e.g. Spectralite), PUR (polyurethanes, e.g. RAVolution), PU / PUR (polyureas, polyurethanes, e.g. Trivex), PTU (polythiourethanes, e.g. MR-8, MR-7) and / or episulfide / polythiol-based polymers (e.g. MR-174).

[0013] Since step c) involves the chemical bonding of the second polymer material to the first polymer material, it can be performed, for example, at a temperature below the softening temperature of the first component. This allows for the high-quality production of the optical element in large quantities. The step of producing the first transparent component can be carried out, for example, using an injection molding or compression molding process. Such processes are characterized by high precision.

[0014] In particular, the first transparent subbody and the top layer can be formed from the same material and / or using the same process.

[0015] Furthermore, it is possible to form the first transparent subbody using the RIM method.

[0016] The optically effective structure can, for example, be designed as a reflective and / or diffractive structure. In particular, the optically effective structure can be designed as a partially reflective structure and / or a wavelength-dependent reflective structure.

[0017] The formation of the first component and / or the application of the top layer can each be carried out in at least two successive steps. This results in reduced shrinkage during the production of the first component and / or the top layer.

[0018] In the process according to the invention, the first and second polymer materials can be materials whose refractive indices differ by no more than 0.005 or 0.001 for at least one wavelength from the predetermined wavelength range. In particular, the refractive indices can differ by no more than 0.0005. With such a small difference in refractive indices, the interface between the two polymer materials virtually disappears optically for the predetermined wavelength range. In particular, the polymer materials can be selected such that they exhibit the same dispersion in the predetermined wavelength range.

[0019] The predetermined wavelength range can be the visible wavelength range, the near-infrared range, the infrared range and / or the UV range.

[0020] To produce the first sub-body according to step a), a primary forming process (such as injection molding, RIM, casting), a forming process (such as thermoforming, hot embossing), or a subtractive and / or separating process (such as diamond machining, ion bombardment, etching) can be used. Of course, it is also possible to combine these processes to produce the first sub-body. In particular, the first sub-body can also be multi-part, with the specified processes being used for each part. Furthermore, known structuring processes can be used for the structured section. The aforementioned processes for producing the first sub-body can also be used for structuring.

[0021] The application of the optically effective coating according to step b) can be carried out, for example, by vapor deposition, sputtering, CVD (chemical vapor deposition), wet coating, etc. The coating can be a single layer. However, it is also possible to apply multiple layers. In particular, an interference layer system can also be applied. Furthermore, at least one adhesion-promoting layer, one mechanical leveling layer, and one protective layer (diffusion / migration, thermal protection, chemical protection, UV protection, etc.) can be applied. The optically effective coating can be designed for specific wavelengths or spectral ranges. It can also, additionally or alternatively, have a function that depends on the angle of incidence, polarization, and / or other optical properties. The optically effective structure can be reflective, in particular highly reflective (e.g.,It may be mirror-like, partially transparent / partially reflective, and / or provide a filtering effect. Furthermore, the optically active coating may be a diffractive optical element.

[0022] Furthermore, the optically effective coating can act as a separating layer, preventing chemical bonding between the second polymer material and the first polymer material in the area of ​​the optically effective structure and causing local demolding that leads to an air gap. In this case, for example, total internal reflection can occur due to the transition from the polymer material to the air gap.

[0023] The optically effective coating can only be applied to the structured section. Alternatively, it is possible to apply the optically effective coating to the entire surface and then remove it from the unused areas. Chemical etching or ion etching, for example, can be used for this removal.

[0024] For the optically effective coating, at least one metal, at least one metal oxide, or at least one metal nitride can be used. An organic material and / or a polymer material can also be used. Furthermore, so-called hybrid materials, such as organic-inorganic hybrid systems or organically modified silanes / polysiloxanes, can be used. A chemically inert or surfactant can be used as the separating layer. Examples include fatty acid derivatives, phosphates, and fluorinated silanes.

[0025] In the method according to the invention, steps a)-c) can be carried out in such a way that the optically effective structure is completely embedded in the transparent body. Thus, the optically effective structure does not extend to any material interface of the transparent body.

[0026] Furthermore, steps a)-c) can be carried out such that the optically effective structure comprises spaced-apart surface segments that provide the desired optical function. These surface segments can, for example, be reflective. The reflective surface segments can cause complete reflection (nearly 100%) or only partial reflection (partially reflective surface segments). In particular, the reflective surface segments do not lie in a common plane. They can be offset parallel to each other.

[0027] The reflective surface pieces can together provide a deflecting effect and, if necessary, also an imaging effect.

[0028] The surface pieces can each be formed as flat surfaces or as curved surfaces.

[0029] In the inventive method, the optical element can be completed after step c). However, it is also possible to perform at least one further material removal machining step, for example to machine or extract the interface of the cover layer pointing away from the first partial body. The same applies to the interface of the first partial body pointing away from the cover layer.

[0030] Of course, at least one surface-coating process step can also be carried out, such as the application of an anti-reflective coating, a hard layer, etc. In particular, the coatings known from the manufacture of spectacle lenses can be applied.

[0031] The finished optical element can thus be provided using the method according to the invention. However, it is also possible that further process steps are necessary to complete the optical element so that it can be used for its intended purpose.

[0032] Furthermore, an optical element with a transparent body in which an optically effective structure is embedded is provided, wherein the optical element is produced by the steps of the method according to the invention (including its further developments).

[0033] In particular, the optical element can be designed as a spectacle lens for a display device that can be placed on a user's head and generates an image, and can have a front and a back, an input section and an output section spaced apart from the input section, and a light guidance channel that guides light beams from pixels of the generated image, which are coupled into the optical element via the input section of the optical element, within the optical element to the output section, from which they are coupled out of the spectacle lens, wherein the output section has the optically effective structure that causes the light beams to be deflected for output.

[0034] Furthermore, a display device is provided with a holding device that can be placed on the head of a user, an image generation module attached to the holding device which generates an image, and an imaging optic attached to the holding device which has an optical element according to the invention and which displays the generated image in the holding device in the state placed on the user's head in such a way that the user can perceive it as a virtual image.

[0035] The imaging optics can consist solely of the optical element. However, it is also possible for the imaging optics to include at least one other optical element in addition to the optical element.

[0036] The display device may include a control unit that controls the image generation module.

[0037] The image generation module can, in particular, comprise a planar image sensor, such as an LCD module, an LCoS module, an OLED module, or a tilting mirror matrix. The image sensor can have a plurality of pixels, which can be arranged, for example, in rows and columns. The image sensor can be self-illuminating or non-self-illuminating.

[0038] The image generation module can be designed in particular to generate a monochromatic or a multiple image.

[0039] The display device according to the invention may include further elements known to those skilled in the art, which are necessary for its operation.

[0040] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations given, but also in other combinations or on their own, without leaving the scope of the present invention.

[0041] The invention will now be explained in more detail, for example with reference to the accompanying drawings, which also reveal essential features of the invention. They show: Fig. 1 an embodiment of the display device according to the invention; Fig. 2 an enlarged partial sectional view of the optical element 1 according to the invention, including a schematic representation of the image generation module; Fig. 3 a schematically enlarged view of the rear side 12 of the optical element 1 in the area of ​​the light guiding channel 17 and the output coupling section 14; Fig. 4 a flowchart describing a method for manufacturing the optical element according to the invention; Fig. 5 an enlarged sectional view of the first transparent partial body to illustrate the manufacturing of the optical element according to the invention; Fig. 6 a sectional view of the first transparent partial body with applied reflective coating; Fig. 7 a sectional view of the first transparent partial body with applied protective layer; Fig. 8 a sectional view of the completed optical element 1 according to the invention; Fig.9 a sectional view of the first transparent partial body to illustrate a modification of the step of applying the protective layer; Fig. 10 a sectional view of the completed optical element according to the invention with a protective layer according to . Fig. 9 Fig. 11 shows a sectional view to illustrate a further embodiment for applying the protective layer; Fig. 12 shows a sectional view of the optical element according to the invention with a protective layer according to Fig. 11 , and Fig. 13 a sectional view of a modification of the optical element according to the invention.

[0042] At the in Fig. 1 In the embodiment shown, the optical element 1 according to the invention is designed as a spectacle lens (here right spectacle lens) of a display device 2 which can be placed on the head of a user.

[0043] The display device 2 comprises a holding device 3, which can be placed on the user's head and may, for example, be designed in the manner of a conventional eyeglass frame, as well as the optical element 1 according to the invention, which serves as the right lens, and a second lens 4, which are attached to the holding device 3. The holding device 3 with the lenses 1 and 4 may, for example, be designed as sports glasses, sunglasses, and / or glasses for correcting a visual impairment, whereby a virtual image can be projected into the user's field of vision via the optical element 1, as described below.

[0044] The display device 2 includes an image generation module 5, which can be arranged in the area of ​​the right temple of the holding device 3, as shown in Fig. 1 The image generation module 5 can have a planar image generation element 6, such as an OLED, LCD or LCoS chip or a tilting mirror matrix, with a large number of pixels arranged, for example, in columns and rows.

[0045] The lenses 1 and 4, and in particular the first lens 1, are described only by way of example together with the display device 1 according to the invention. The lenses 1, 4, or at least the first lens 1, are each designed individually as a lens 1, 4 according to the invention or as an optical element according to the invention. The optical element according to the invention can also be used in a context other than with the display device 2 described here. Furthermore, if the optical element 1 is designed as a lens, it can of course also be designed as a second lens 4.

[0046] How best to view the enlarged partial section view in Fig. 2 As can be seen, the display device 2 has an imaging optic 7 which includes a lens 8 arranged between the image-generating element 6 or the image transmitter 6 and the first spectacle lens 1. Furthermore, the first spectacle lens 1 itself also serves as part of the imaging optic 7.

[0047] Each pixel of the image sensor 6 can emit a light beam 9. The desired image can be generated by appropriately controlling the pixels of the image sensor 6 by means of a control unit 19, which can be part of the image generation module 5. Fig. 2 The path of a light ray is shown as a representative of the light beam 9, so that the following text will also refer to light ray 9.

[0048] The light ray 9 emanating from the image sensor 6 passes through the lens 8 and enters the first spectacle lens 1 via an end face 10. The light ray 9 then strikes a front surface 11 of the first spectacle lens 1, the angle of incidence being such that total internal reflection occurs. After another total internal reflection at a rear surface 12 of the first spectacle lens 1, the light ray 9 strikes one of several reflective deflecting surfaces 13 of an output coupling section 14 of the first spectacle lens 1 and is reflected by the reflective deflecting surface 13 to the rear surface 12 in such a way that the light ray exits the first spectacle lens 1 via the rear surface 12.

[0049] Thus, when a user wears the display device 2 according to the invention on their head as intended, they can perceive the image generated by the image sensor 6 as a virtual image when looking at the output section 14. In the embodiment described here, the user must look slightly to the right relative to the viewing direction G of a straight-ahead view. Fig. 2 For clarity, the pivot point 15 represents the user's eye, and the eyebox 18, or exit pupil 18 of the imaging optics 7, is shown. The eyebox 18 is the area provided by the display device 2 within which the user's eye can move while still seeing the generated image as a virtual image.

[0050] The section of the first spectacle lens 1 through which the light beam 9 is coupled into the spectacle lens 1 can be referred to as the coupling section 16. Although coupling via the front face 10 is described in the embodiment, it is also possible to perform coupling via the back face 12 of the first spectacle lens 1.

[0051] The areas of the front and back 11, 12 of the first spectacle lens 1, in which the light beam 9 is guided by internal total reflection from the coupling section 16 to the coupling section 14, form a light guidance channel 17 in which the light beams 9 are guided from the coupling section 16 to the coupling section 14.

[0052] In the presentation in Fig. 2 Only one total internal reflection is shown at the front 11 and the back 12. This is to be understood as a purely schematic representation. Of course, multiple total internal reflections can occur. Furthermore, it is also possible to provide the front and / or back surface in the area of ​​the light-guiding channel 17 with a reflective or partially reflective coating, so that the light guidance in the light-guiding channel 17 is effected by normal reflection at the corresponding reflective surface. It is also possible to arrange one or two reflective layers in the first lens 1, each spaced apart from the front 11 and back 12, which serve to guide the light and thus (at least partially) form the light-guiding channel 17.

[0053] In the Fig. 3 The front view 11 shows schematically the coupling section 16, the light guidance channel 17 and the coupling section 14 with the reflective deflection surfaces 13 (or reflective facets 13).

[0054] A method for manufacturing the optical element 1 according to the invention is described below.

[0055] In a first step S1 ( Fig. 4 ) a first partial body 20, transparent for a predetermined wavelength range, is produced by injection molding, which is in Fig. 5 The first component 20, shown, is made of a thermoplastic material. It has a front interface 21 and a rear interface 22. The rear interface 22 can, for example, form the back side 12 of the completed optical element 1. The predetermined wavelength range here is the visible wavelength range, which extends from approximately 380 nm to 780 nm.

[0056] On the front interface 21, the first transparent subbody 20 has a structure 23 which is shown in the Fig. 4 The enlarged sectional view of part of the first transparent subbody 20 clearly shows the structure. The structuring is a zigzag structure with curved main flanks 24, each connected to secondary flanks 25. The main flanks 24 are shown curved here. However, they can also be planar. The in Fig. 4 The first transparent partial body 20 shown can also be referred to as an intermediate injection molding part.

[0057] The first transparent subbody 20 according to Fig. 4 If necessary and / or desired, the component can be cleaned in step S2 and activated for a subsequent coating step S3. Activation can be limited to the main flanks 24 to be coated. For cleaning and activation, the first component 20 can be immersed in an ultrasonic bath. Activation can be carried out, for example, using a basic solution or by means of a spark discharge. A thin lacquer layer with a thickness in the range of 2 to 10 µm can also be applied for activation. Alternatively, a SeO₂ coating with a thickness of a few tens of nm can be applied. This can be done, for example, by plasma, CVD (chemical vapor deposition), or PVD (physical vapor deposition).

[0058] In the coating step S3, only the structuring 23 (and here only the main flanks 24) is provided with a reflective coating 26 ( Fig. 6 ). This can be achieved, for example, by appropriately masking the front interface 21 and subsequent sputtering, painting or applying a coating and / or vapor deposition (e.g., by chemical deposition from the gas phase or physical deposition from the gas phase).

[0059] After step S3, a cleaning and activation step can be performed as step S4. Step S4 can be the same as or similar to step S2.

[0060] Next, in step S5, the structuring 23 and in particular the reflective coating 26 are covered with a protective layer 27 ( Fig. 7 For this purpose, a chemically crosslinking polymer is applied, which ideally has the same optical properties as the material for the first transparent sub-body 20. The application of the chemically crosslinking polymer is preferably carried out using a so-called RIM process (Reaction Injection Moulding process). In this process, two components, such as polyol and isocyanate, are mixed together and then injected under pressure into a mold in which the first transparent sub-body 20 is positioned so that the desired formation of the protective layer 27 occurs. The two components react with each other so that the desired chemically crosslinked polymer (here, for example, polyurethane) is formed.

[0061] The advantage of using the RIM process is that the required pressure is significantly lower compared to conventional injection molding of thermoplastic materials, which ensures that the structuring 23 with the reflective coating 26 is not damaged when the protective layer 27 is applied.

[0062] After applying the protective layer 27, a further injection molding step S6 (which can also be referred to as overmoulding) is carried out with the same material as for the first transparent sub-body in order to apply a finishing or cover layer 28 and thus complete the optical element ( Fig. 8 The finishing layer 28 can also be referred to as the top layer 28. In Fig. 8 A dashed dividing line is shown between the final layer 28 and the first transparent subbody 20 to distinguish the two elements 28 and 20. In reality, no such dividing line exists.

[0063] The described process steps ensure that the optical element 1, in addition to the structuring 23, is homogeneously constructed from one material and has identical or nearly identical properties (in particular mechanical, optical, chemical and / or physical properties), since the same material is used in the injection molding of the first transparent sub-body 20 and in the application of the final layer 28 to complete the optical element 1.

[0064] The materials for the first transparent subbody 20 and the final or cover layer 28 are preferably selected such that the refractive indices of the two materials differ by no more than 0.001 and, in particular, by no more than 0.0005 for at least one wavelength from the predetermined wavelength range. In particular, the materials are selected such that the dispersion in the predetermined wavelength range is the same or differs only so slightly that this does not have any adverse optical effect during the intended use of the optical element 1 according to the invention.

[0065] After step S6, a relaxation tempering process can optionally be carried out as step S7.

[0066] Furthermore, optionally, as step S8, the front side 11 formed by the material interface of the cover layer 28 pointing away from the first sub-body 20 can be treated.

[0067] This can be achieved, for example, by applying a hard coating (polysiloxane), an anti-reflective coating, or other coatings.

[0068] With the described procedure, it is possible to freely place the decoupling section 14 in the volume of the completed optical element 1 according to the invention and thus also to protect it against external environmental influences.

[0069] In Fig. 9 is a modification of step S5 according to Fig. 7 shown. In this modification, the RIM process is carried out in such a way that the depressions formed by the main and secondary flanks 24, 25 are not completely filled. The corresponding finished optical element is shown in Fig. 10 It is shown here in the same way as in Fig. 8 A dashed dividing line has been drawn, which, however, does not actually exist.

[0070] In Fig. 11 is a variation of step S5 according to Fig. 7 shown, in which the coating is carried out using the RIM process such that the entire front interface 21 is coated. Then, in step S6, the thermoplastic material is applied to complete the optical element 1 according to the invention, as shown in Fig. 12 as indicated.

[0071] In another variation, after step S3 according to Fig. 6 or after step S4, RIM step S7 is carried out in such a way that the final layer 28 is formed by means of this step, which also simultaneously fills the structuring 23 and, in particular, covers the reflective coating 26. The completed optical element 1 is shown schematically in Fig. 13 The dividing line between the first transparent subbody 20 and the final layer 28 is shown. It is only intended to illustrate that the two layers were produced sequentially. Since the final layer 28 is produced using the RIM process, the material is chemically bonded, so that no visible separation layer is present. The depicted separation layer serves only to clarify the process steps carried out.

[0072] In a variation of the one associated with Fig. 4 bis 13 In the described process, the first transparent sub-body 20 cannot be formed by injection molding, but rather by compression molding or compression molding. Furthermore, it is possible to produce the first transparent sub-body 20 using the RIM process.

[0073] In all process steps, the described layers can be formed in one or more steps. For example, the first transparent sub-body 20 can be formed in two or more steps. The same applies to the final layer 28. This is particularly advantageous with regard to the unavoidable shrinkage during layer production, as shrinkage is volume-dependent. When the layer is formed from several sub-layers, the overall shrinkage is lower compared to forming the layer as a whole in one step. Forming the first transparent sub-body 20 and / or the final layer 28 from several sub-layers in two or more successive steps is particularly advantageous when using the RIM process, as this process typically exhibits relatively high volume shrinkage, which can easily range from 5 to 15%.

[0074] In the RIM process, the crosslinking of the polymer can be induced not only by mixing two components, but also, for example, thermally and / or by UV exposure.

Claims

1. Method for producing an optical element (1) comprising a body which is transparent to a predetermined wavelength range and in which an optically effective structure (14) is embedded, the method comprising the following steps a) providing a first partial body (20) which is transparent to the predetermined wavelength range and which has a structured portion (23) on its top side (21); b) applying a coating (26) which is optically effective for the predetermined wavelength range to the structured portion (23) in order to form the optically effective structure (14), and c) applying a cover layer (28) transparent to the predetermined wavelength range on the top side (21) of the first partial body (20) including the structured portion (23); wherein after step b) and before step c) a protective layer (27) of thermosetting material is applied to the optically effective coating (26) by casting, characterized in that in step c) the cover layer (28) is applied to the protective layer (27) by casting thermoplastic material.

2. Method according to Claim 1, wherein steps a)-c) are carried out in such a way that in step b) a reflective coating (26) is applied as an optically effective coating (26) .

3. Method according to Claim 1 or 2, wherein steps a)-c) are carried out in such a way that the optically effective structure (14) has spaced apart reflective surface elements (13).

4. Method according to any of the preceding claims, wherein the application of the cover layer (28) in step c) is carried out in at least two successive partial steps.

5. Method according to any of the preceding claims, wherein in step c) the cover layer (28) is formed on the entire top side (21) of the first partial body (20) including the protective layer (27).

6. Method according to any of the preceding claims, wherein the first partial body (20) is formed from a first polymer material and in step c), for applying the cover layer (28), a second polymer material is applied to the top side (21) of the first partial body (20), and the second polymer material is chemically bonded to the first polymer material.

7. Method according to Claim 6, wherein materials whose refractive indices differ by no more than 0.005 for at least one wavelength from the predetermined wavelength range are used as the first and second polymer materials.

8. Method according to any of the preceding claims, wherein in step c) the thermoplastic material is applied by means of an injection moulding process.

9. Method according to any of the preceding claims, wherein in order to provide the first partial body (20) in step a), the latter is formed from thermosetting material by means of a RIM method.

10. Method according to Claim 9, wherein the thermosetting material is applied by means of the RIM method in at least two successive partial steps.

11. Method according to any of the preceding claims, wherein the cover layer (28) in step c) is formed such that an interface of the cover layer (28) facing away from the first partial body (20) forms an interface of the optical element (1).

12. Method according to any of the preceding claims, wherein steps a)-c) are carried out in such a way that the optically effective structure (14) is completely embedded in the transparent body.

13. Optical element having a transparent body (20, 28) in which an optically effective structure (14) is embedded, produced by the steps of any of Claims 1 to 12.

14. Optical element according to Claim 13, designed as a spectacle lens for a picture-generating display device (2) wearable on the head of a user and comprising a front side (11) and a rear side (12), an input coupling portion (16) and an output coupling portion (14) spaced apart from the input coupling portion (16) and a light guide channel (17) which is suitable for guiding light beams (9), which are coupled into the optical element (1) via the input coupling portion (16) of the optical element (1), in the optical element (1) from pixels of the generated image to the output coupling portion (14), from which they are coupled out of the optical element (1), wherein the output coupling portion (14) comprises the optically effective structure which brings about a deflection of the light beams (9) for output coupling purposes.

15. Display device comprising a holding device (3), which is wearable on the head of a user, a picture-generating module (5), which is secured to the holding device (3) and generates an image, and an imaging optics unit, which is secured to the holding device (3), which comprises an optical element (1) according to Claim 14 and which, in the state in which the holding device (3) is worn on the head of the user, images the generated image such that the user can perceive said image as a virtual image.