Layer system, in particular for displaying high-contrast images

Abstract

The invention relates to a layer system (2) for displaying images, in particular for displaying high-contrast images. The layer system is designed such that, when light (5) passes through the layer system, an image is generated. The layer system has an image layer. The image layer is designed such that, when light passes through the image layer, the image is generated with a first intensity distribution. The layer system also has a reducing layer. The reducing layer is designed to reduce the intensity of light passing through the reducing layer such that, when light passes through the reducing layer and the image layer, the image is generated with a second intensity distribution. The difference between the greatest intensity of the first intensity distribution and the least intensity of the first intensity distribution is less than the difference between the greatest intensity of the second intensity distribution and the least intensity of the second intensity distribution.

Description

[0001] Layer system, especially for displaying high-contrast images

[0002] The invention relates to a layer system for displaying images, in particular for displaying high-contrast images. The invention further relates to a display device for displaying images using a layer system, to a method for producing a layer system for displaying images, and to a reduction layer for use with an image layer.

[0003] A high-contrast image, also known as a "high dynamic range" image or simply an HDR image, is generally defined as an image with a particularly large dynamic range, meaning a particularly large difference in brightness between the brightest and darkest points in the image. To better distinguish HDR images, images with the smaller dynamic range traditionally used in technology are often referred to as "standard dynamic range" images, or SDR images for short. HDR images are becoming increasingly important, especially in photography, because they can better represent the naturally occurring and visually perceptible large differences in brightness than SDR images.

[0004] Capturing, storing, processing, and playing back HDR images requires specialized equipment, techniques, and media designed for exceptionally wide dynamic range. Playing back HDR images is particularly challenging, and most conventional media are unsuitable for this purpose without drastically reducing the dynamic range. For example, conventional printing media, such as layered ink systems on white paper, create a perceptible image by reflecting ambient light. The achievable dynamic range is limited by the maximum intensity of light reflected by, say, white paper, and the minimum intensity reflected by, say, black ink, and is generally many times smaller than the dynamic range of HDR images.

[0005] It is therefore an object of the present invention to provide a layer system for displaying images that can generate an image with a large dynamic range. It is a further object of the present invention to provide a display device for displaying images using the provided layer system, a method for producing the provided layer system, and a reduction layer for use with an image layer.

[0006] The problem is solved by a layer system for displaying images, in particular for displaying high-contrast images, wherein the layer system is designed such that an image is generated when light passes through the layer system, wherein the layer system has:

[0007] an image layer, wherein the image layer is designed such that when light passes through the image layer, the image is generated with a first intensity distribution,

[0008] a reducing layer, wherein the reducing layer is configured to reduce the intensity of light passing through the reducing layer in such a way that, when light passes through the reducing layer and the image layer, the image is produced with a second intensity distribution,

[0009] where the difference between the greatest intensity of the first intensity distribution and the smallest intensity of the first intensity distribution is smaller than the difference between the greatest intensity of the second intensity distribution and the smallest intensity of the second intensity distribution.

[0010] The image to be displayed is generated as light passes through the layer system, so the maximum brightness of the image can be increased with minimal effort by increasing the intensity of the light striking the layer system. The image layer is designed such that, as light passes through it, the image is generated with a first intensity distribution. However, the difference between the highest and lowest intensities of this first intensity distribution is smaller than the difference between the highest and lowest intensities of a second intensity distribution, which is generated as light passes through both the image layer and the reduction layer. Therefore, the dynamic range achievable by the image layer alone is smaller than the dynamic range achievable by both the image layer and the reduction layer together. Consequently, the image layer can be designed for high-quality image reproduction.The reduction layer, on the other hand, can be designed to adjust the intensity of the light passing through the layer system across a wide intensity range, thus enabling high-quality dynamic range adjustment. In particular, the minimum brightness of the image can be reduced by using the reduction layer without requiring complex adjustments to the image layer that might otherwise compromise image quality. Therefore, the dynamic range required for displaying HDR images can be achieved with this layer system.

[0011] The layer system comprises at least two layers: an image layer and a reduction layer. The layer system may also include additional layers. Here, a layer refers to a two-dimensional object or a two-dimensional arrangement of two-dimensional objects. A layer generally has two side lengths, referred to here and in the following as width and height, which are significantly larger than the third side length, referred to here and in the following as thickness. The individual layers of the layer system are arranged such that the planes spanned by the width and height of the individual layers are essentially parallel. A gap may remain between the individual layers of the layer system, or the individual layers may lie directly adjacent to one another. In particular, the image layer and the reduction layer may be spaced apart from each other or lie directly adjacent to one another.The individual layers of the layer system can be interconnected. In particular, the image layer and the reduction layer can be interconnected. In a preferred embodiment, the image layer and the reduction layer lie directly adjacent to each other and are interconnected. In this embodiment, the image layer and the reduction layer are preferably interconnected over a surface area.

[0012] Here and in the following, unless otherwise stated, the term "light" refers to a mixture of electromagnetic radiation with different wavelengths, the electromagnetic radiation being partly or entirely attributable to the visible part of the electromagnetic spectrum.

[0013] The layer system is designed such that an image is formed when light passes through it. The passage of light through the layer system refers to light striking one of the two flat surfaces of the layer system and exiting from the opposite flat surface. The first flat surface of the layer system could be called the back, and the second flat surface could be called the front. The layer system is designed such that light striking the back surface causes light to exit from the front surface. In particular, the light striking the back surface can exit completely or partially from the front surface. The layer system is therefore designed to allow light to pass through it and could accordingly be described as partially transparent.When light passes through a layered system, an interaction occurs between the light and the system. For example, a light source could be positioned on one side of the system, so that light emitted from the light source strikes one of the two flat surfaces of the system. In the same example, an observer could be positioned on the other side of the system, so that the observer is looking at the other flat surface. When light from the light source strikes one of the flat surfaces of the system, it can be partially or completely transmitted, scattered, diffracted, or absorbed. A combination of these interactions is also possible. The portion of the light striking the system that is transmitted passes through the system and can be perceived by the observer.The portion of light striking the layered system that is scattered and / or diffracted partially passes through the layered system. This portion can also be perceived by the observer. The portion of light striking the layered system that is absorbed does not pass through the layered system and therefore cannot be perceived by the observer.

[0014] Here, an image generally refers to a two-dimensional representation of visual content. For example, an image can be a photograph, a drawing, a painting, a computer-edited or created photograph or artwork, or even a photograph or artwork edited or created using artificial intelligence systems. Preferably, the image is a photograph. The reproduced photograph may have been edited or altered after it was taken, for example, using digital processing techniques.

[0015] In the present invention, the image is generated when light passes through the layer system. The generation of the image thus refers to a modification of the light passing through the layer system. This modification can be caused, for example, by one of the aforementioned interactions of the light with the layer system. The optical properties of the layer system are generally spatially inhomogeneous. The light passing through the layer system is modified in such a way that an observer can visually perceive the content to be reproduced by the image. In one example, the layer system is configured such that when white light passes through it, an image is generated that reproduces a photograph of a predominantly green treetop against a blue sky.In the area of ​​the tree canopy, the optical properties of the layered system are such that predominantly green light is transmitted and / or diffusely scattered, while light of other colors is predominantly absorbed. In the area of ​​the sky, however, the optical properties of the layered system are such that predominantly blue light is transmitted and / or diffusely scattered, while light of other colors is predominantly absorbed. In this example, the layered system could be illuminated with white light. To an observer of the light passing through the layered system, the area of ​​the tree canopy would then appear green and the area of ​​the sky blue.

[0016] An intensity distribution of light passing through a layer can generally refer to a spatial distribution of the intensity of the light passing through the layer and / or a spectral distribution of the intensity of the light passing through the layer. The spatial distribution of the intensity of the light passing through the layer refers to the spatially resolved distribution of the intensity. For example, the intensity of the light passing through the layer emanating from that region of the layer can be specified. In particular, a surface element can be defined for each point in the layer from which light passing through the layer emanates, and the intensity of the light emanating from this surface element can be specified for each point in the layer. The spectral distribution of the intensity of the light passing through the layer refers to the intensity of the light as a function of the wavelength of the light.

[0017] The layer system comprises an image layer, which is designed such that when light passes through it, an image with a first intensity distribution is generated. Here, an intensity distribution refers to the distribution of the intensity of the light passing through the image layer. The first intensity distribution preferably refers to a spatial distribution of the intensity of the light passing through the image layer. In general, the intensity distribution of the light striking the image layer differs from the intensity distribution of the light passing through it, because the light striking the image layer interacts with it. As described above, the nature of these interactions depends, among other things, on the properties of the light striking the image layer and the optical properties of the image layer.Particularly due to the wavelength dependence of the interactions, the spectral distribution of the intensity of the light passing through the image layer can differ from the spectral distribution of the intensity of the light striking the image layer. Furthermore, particularly due to spatially inhomogeneous optical properties of the image layer, the spatial distribution of the intensity of the light passing through the image layer can differ from the spatial distribution of the intensity of the light striking the image layer.

[0018] It should be understood that while the image layer is designed to produce an image with a first intensity distribution when light passes through it, this is not necessarily the case when light passes through the entire layer system. The image layer is only one of at least two layers in the system. Depending on the direction of propagation of the light striking the system and the arrangement of the layers, the light might, for example, first pass through the reducing layer and then strike the image layer. In such a situation, the image with the second intensity distribution is produced directly when light passes through the image layer.

[0019] Furthermore, the layer system comprises a reducing layer, which is configured to reduce the intensity of light passing through it such that, upon passing through the reducing layer and the image layer, the image is produced with a second intensity distribution. Here, an intensity distribution refers to the distribution of the intensity of the light passing through the reducing layer and the image layer. The second intensity distribution preferably refers to a spatial distribution of the intensity of the light passing through the reducing layer and the image layer. In general, the intensity distribution of the light incident on the layer system differs from the intensity distribution of the light passing through the reducing layer and the image layer because the light incident on the layer system interacts with the reducing layer and the image layer.In one embodiment, the second intensity distribution is generated when the light striking the layer system first strikes the image layer and then the reducing layer. In a preferred embodiment, the second intensity distribution is generated when the light striking the layer system first strikes the reducing layer and then the image layer.

[0020] The image layer and the reduction layer are further configured such that the difference between the highest and lowest intensities of the first intensity distribution is smaller than the difference between the highest and lowest intensities of the second intensity distribution. To assess whether a first difference is greater or smaller than a second difference, the differences can be quantified. For example, a difference between a first intensity li and a second intensity h can be quantified by considering one of the following quantities:

[0021] a quotient I1 / I2 of the first intensity and the second intensity,

[0022] A difference li - h between the first intensity and the second intensity, a quotient (I i - l2) / (l 1 + I2) of the difference between the first intensity and the second intensity and the sum of the first intensity and the second intensity. Preferably, the difference between a first intensity h and a second intensity h is quantified as the quotient I1 / I2. A first intensity h can, in particular, be the intensity of the light emanating from a first region or a surface element arranged at a first point. A second intensity I2 can, in particular, be the intensity of the light emanating from a second region or a surface element arranged at a second point, wherein the second region is different from the first region or the second point is different from the first point.A first intensity I1 and a second intensity I2 can therefore refer in particular to intensities that are described by a spatial intensity distribution.

[0023] Preferably, the difference between the highest intensity of the first intensity distribution and the lowest intensity of the first intensity distribution is considered to be smaller than the difference between the highest intensity of the second intensity distribution and the lowest intensity of the second intensity distribution, if this condition is met for at least one wavelength.

[0024] In one embodiment, the intensity distributions can refer to illumination using a specific light source. This light source can, for example, be a transparency unit of a display device that holds the layer system in such a way that the light from the transparency unit shines through the layer system. Alternatively, the specific light source can be designed to emit standard illuminant with a color temperature of 5000 K, also known as D50 standard illuminant.

[0025] To compare the two intensity distributions, the image with the first intensity distribution can be generated, for example, if the irradiance generated by the light in the region of the image layer (i.e., relative to the light incident on the image layer) is spatially homogeneous, and if the direction of propagation of the light in the region of the image layer is essentially spatially homogeneous. Preferably, the image with the second intensity distribution is generated if 1) the light first strikes the reducing layer, the irradiance generated by the light in the region of the reducing layer is spatially homogeneous, and the direction of propagation of the light in the region of the reducing layer is essentially spatially homogeneous, or if 2) the light first strikes the image layer, the irradiance generated by the light in the region of the image layer is spatially homogeneous, and the direction of propagation of the light in the region of the image layer is essentially spatially homogeneous.The intensity of light emanating from a region or area element generally quantifies how much light is emitted from that region or area element. This can specify how much light of a particular wavelength is emitted from the region or area element, and / or how much light of a specific wavelength range is emitted from the region or area element. Preferably, the first and second intensity distributions each describe how much light from the visible portion of the electromagnetic spectrum is emitted from a region or area element of the image layer and the reducing layer, respectively. For example, the first intensity distribution could describe the radiant flux of visible light emanating from a region or area element of the image layer after having passed through it (i.e., radiant flux per unit area).In the same example, the second intensity distribution could 1) describe the radiant flux of visible light emanating from an area or surface element of the image layer, having previously passed through the reducing layer and then through the image layer, if the light has first passed through the reducing layer and then through the image layer, or 2) describe the radiant flux of light emanating from an area or surface element of the reducing layer, having previously passed through the reducing layer and then through the image layer, if the light has first passed through the image layer and then through the reducing layer. In another example, the first intensity distribution could describe the area-specific luminous flux of light emanating from an area or surface element of the image layer, having previously passed through the image layer.In the same example, the second intensity distribution could 1) describe the area-specific luminous flux of the light emanating from a region or surface element of the image layer, having previously passed through the reducing layer and the image layer, if the light has first passed through the reducing layer and then through the image layer, or 2) describe the area-specific luminous flux of the light emanating from a region or surface element of the reducing layer, having previously passed through the reducing layer and then through the image layer, if the light has first passed through the image layer and then through the reducing layer. In a preferred embodiment, the first intensity distribution describes, for each point on the image layer, the maximum luminance caused by the light emanating from that point on the image layer, having previously passed through the image layer.In the same preferred embodiment, the second intensity distribution describes 1) for each point of the image layer the maximum luminance caused by the light emanating from that point of the image layer, having previously passed through the reducing layer and the image layer, when the light has first passed through the reducing layer and then through the image layer, or 2) for each point of the reducing layer the maximum luminance caused by the light emanating from that point of the reducing layer, having previously passed through the reducing layer and the image layer, when the light has first passed through the image layer and then through the reducing layer.In this embodiment, for example, the difference between the highest and lowest intensity of the first intensity distribution would be the difference between the highest and lowest maximum luminances produced at two corresponding points on the image layer by the light that has previously passed through the image layer. Here, the highest maximum luminance denotes the highest value of the first intensity distribution, and the lowest maximum luminance denotes the lowest value of the first intensity distribution. The adjective "maximum" thus refers to the fact that, in this embodiment, the first intensity distribution describes the maximum luminance for each point, with this value being lowest for one point on the image layer and highest for another.

[0026] As described above, the optical properties of the image layer and the reducing layer are generally spatially inhomogeneous. The individual layers of the layer system, in particular the image layer and the reducing layer, are designed and arranged such that a region of the reducing layer with defined optical properties can be assigned to a region of the image layer with defined optical properties, and vice versa. For example, the reducing layer and the image layer can be designed and arranged such that light falling on a region of the reducing layer and passing through it in that region subsequently falls predominantly on the corresponding region in the image layer and partially passes through it.The reduction layer and the image layer can also be designed and arranged such that light falling on and passing through an area of ​​the image layer subsequently falls predominantly on the corresponding area in the reduction layer and partially passes through it. The properties of the light passing through the reduction layer and the corresponding area of ​​the image layer therefore depend on the optical properties of both the reduction layer and the image layer in their respective areas. This allows the layer system to produce an even higher quality HDR image.

[0027] The interaction of the image layer and the reducing layer enables the creation of an image with a particularly large dynamic range, meaning a particularly large difference between the intensity of the light emanating from the brightest point of the layer system and the intensity of the light emanating from the darkest point of the layer system. The reducing layer generates a specific spectral and / or spatial intensity distribution of the light passing through it, primarily because light striking the reducing layer only partially passes through it. Similarly, the image layer generates a specific spectral and / or spatial intensity distribution of the light passing through it, primarily because light striking the image layer only partially passes through it. Thus, a reduction in the intensity of the light occurs as it passes through the reducing layer or the image layer.The dynamic range of an image produced when light passes through the reducing layer and the image layer is therefore particularly large if the reducing layer and the image layer are designed and arranged such that in one region of the layer system there is a very small reduction in the intensity of the light, while in another region there is a very large reduction in the intensity of the light. The image layer is designed such that the dynamic range achievable when light passes through it is smaller than the dynamic range of the image to be produced by the layer system. In one example, there could therefore be regions of the image layer where the intensity distribution produced when light passes through the image layer differs significantly from the intensity distribution of the corresponding region of the image to be produced by the layer system.Particularly dark areas of the image to be generated could therefore appear too dark or too bright overall, depending on the intensity of the light passing through the image layer, if the light passes only through the image layer. Furthermore, particularly dark areas of the image to be generated could appear too low in contrast if the light passes only through the image layer. In these very dark areas, the intensity of the light cannot be sufficiently reduced by the image layer alone to achieve the desired intensity distribution. In a preferred embodiment, the reducing layer is designed such that in areas where the image layer reduces the intensity of the light passing through it most significantly, the intensity of the light passing through the layer system is further reduced by the reducing layer.The reduction layer thus formed allows the intensity of light passing through the layer system to be sufficiently reduced to produce the desired intensity distribution even in very dark areas. In one embodiment, the reduction layer is identical to the image layer. In this embodiment, the reduction layer could also be described as a copy of the image layer. As described above, the layer system can comprise two or more layers, with the layer system including at least the image layer and the reduction layer. The layer system is designed such that the image to be displayed is generated when light passes through it.The image layer is further configured such that when light passes through it, the image is generated with a first intensity distribution, and the reduction layer is configured such that when light passes through both the reduction and image layers, the image is generated with a second intensity distribution. In particular, the image layer is thus configured to contain image information about the image to be displayed. In preferred embodiments, the reduction layer is also configured to contain image information about the image to be displayed. In addition to the image layer and the reduction layer, the layer system can comprise further layers that do not contain image information. These further layers can also influence the intensity distribution generated when light passes through the layer system, even if they are not part of the image layer or the reduction layer.For example, the reduction layer and the image layer can be attached to a mechanically stable frame layer, which provides greater mechanical stability to the layer system. Such a frame layer can be completely opaque to visible light and cover the edge regions of the image layer and / or the reduction layer. However, the frame layer is not part of the image layer or the reduction layer, so the first intensity distribution and the second intensity distribution are not affected by the frame layer, even though the overall intensity distribution produced when light passes through the layer system is affected by the frame layer, since no light can pass through the layer system at the edges. In another example, an artist might sign a layer system designed to represent one of their digitally created artworks in black ink.The signature might, for example, be applied to the image layer, but it is not part of the image layer itself. Therefore, the signature does not affect the first intensity distribution or the second intensity distribution, even though the overall intensity distribution generated when light passes through the layer system is influenced by the signature.

[0028] The image layer and the reduction layer can each be composed of several sublayers. In a preferred embodiment, the image layer comprises an image layer support layer. The image layer support layer can have a front and a back side. The image layer support layer can be configured such that its optical properties are homogeneous. For example, the image layer support layer can be configured such that light incident on the image layer support layer is predominantly transmitted uniformly, and only a small fraction of the light incident on the image layer support layer is reflected, scattered, or absorbed. The image layer support layer can further be configured to provide mechanical stability to the image layer.

[0029] In one embodiment, the image layer support layer comprises a plastic film. Preferably, the plastic film of the image layer support layer comprises a transparent polyethylene-based plastic film. It has been shown that a polyethylene-based plastic film is particularly suitable for providing the image layer with mechanical stability without significantly affecting its optical properties. With such an image layer, an HDR image of even higher quality can be generated when light passes through the layer system.

[0030] In a preferred embodiment, the image support layer comprises a layer of polymethyl methacrylate, also known as acrylic glass. Preferably, the polymethyl methacrylate layer is formed as a sheet. Polymethyl methacrylate sheets can be designed to exhibit very homogeneous optical properties. At the same time, polymethyl methacrylate sheets can be designed to provide advantageous mechanical stability. It has therefore been shown that a polymethyl methacrylate sheet is particularly well suited as an image support layer.

[0031] In a preferred embodiment, the image layer comprises one or more colorant layers. A colorant layer is a layer containing one or more colorants, the optical properties of which are determined by the optical properties of the colorants it contains. A colorant is a coloring substance. Colorants can be, for example, pigments or dyes. A colorant layer can, for example, contain pigments encapsulated by a binder. Depending on the required optical properties of the colorant layer, it may contain only one type of pigment or a mixture of different types of pigments. Furthermore, the pigments can be present in the colorant layer in varying concentrations. A colorant layer can contain a dye or a mixture of dyes.The dye or mixture of dyes can itself form the colorant layer or be embedded in a binder. Furthermore, the colorant layers can include other components, such as fillers, additives, or residual solvents. The optical properties of a colorant layer are determined by the interactions of light with the colorant layer. In particular, the colorant layer can partially or completely transmit, scatter, diffract, or absorb incident light. The extent of these interactions can also be wavelength-dependent. The colorant layer is therefore capable of altering the color and intensity of light passing through it and can thus determine the optical properties of the image layer. As light passes through the image layer, the colorant layer can create different color impressions for the viewer.For example, when white light strikes the pigment layer, some of the light may be absorbed, while the remaining portion is predominantly transmitted or diffusely scattered. In this case, the viewer's color perception is determined by the properties of the transmitted light and / or the properties of the diffusely scattered light. It should be understood that if the pigment layer is predominantly absorbed, the image layer can also appear black. Therefore, here and in the following, the term "pigment" can also refer to a black pigment.

[0032] The colorant layers of the image layer can be produced in different ways. In one embodiment, the colorant layers of the image layer were produced by applying colorants. This production can also include the application of other components of the colorant layer, for example, the application of mixtures that may include colorants, binders, solvents, additives, and fillers. In this embodiment, the image layer preferably comprises an image layer support layer, wherein the colorant layers of the image layer were produced by applying colorants to the image layer support layer. In particular, the application of colorants to produce the colorant layers of the image layer can be carried out using a digital printing process.Examples of suitable digital printing processes include electrophotography, toner printing, inkjet printing, and dye-sublimation. Dye-sublimation is particularly suitable for printing on transparent substrates, such as transparent image carrier layers. The application of colorants to create the image layer's colorant layers can also be achieved using screen printing. In one embodiment, the image layer's colorant layers are created by applying colorants using an inkjet printing process and UV-curing inks. Preferably, the inkjet printing process for applying colorants is carried out using a flatbed printer.Such an inkjet printing process using a flatbed printer is advantageous because the substrate to be printed does not need to be moved during the printing process, thus allowing, for example, the positioning of the substrate to be maintained with high accuracy during printing. The use of UV-curing ink is advantageous because the ink heats up only slightly during printing, resulting in minimal heat exposure to the substrate, while simultaneously achieving high pixel sharpness. Applying colorants to create the colorant layers of the image layer using one of the aforementioned printing processes is particularly advantageous when a polymethyl methacrylate plate is used as the image layer support. It has been shown that this further enhances the quality of the HDR image produced by the layer system.

[0033] In a preferred embodiment, the colorant layers of the image layer are produced by a photochemical process. Preferably, in this embodiment, the image layer comprises an image layer support layer, wherein the colorant layers of the image layer are produced by exposing one or more photosensitive layers applied to the image layer support layer and subsequently developing them. Corresponding photochemical processes are described in detail below. Producing the colorant layers of the image layer by a photochemical process offers several advantages. Firstly, photochemical processes enable the production of colorant layers of very high quality. Secondly, in the photochemical process, colorants are produced and / or incorporated into existing photosensitive layers without causing uneven changes in the thickness of the layers.In particular, this allows the amount of pigment in the photochemically produced pigment layers to be varied without changing the thickness of the pigment layers. The image layer can therefore have a uniform and only slightly structured surface. It has been shown that with such a well-designed image layer, an HDR image of even higher quality is produced when light passes through the layer system.

[0034] In a preferred embodiment, the image layer comprises a protective layer, wherein the colorant layers of the image layer are arranged between the image layer support layer and the protective layer. Arranging the colorant layers of the image layer between the image layer support layer and the protective layer offers the advantage of protecting the colorant layers from damage. Since the colorant layers determine the optical properties of the image layer, damage to these layers would impair the quality of the image produced by the layer system. Protecting the colorant layers also simplifies the handling of the layer system, as it reduces the likelihood of compromising the optical properties of the image layer. This allows the layer system to produce an HDR image with even less effort and in even higher quality.

[0035] The protective layer can be designed such that its optical properties are homogeneous. For example, the protective layer can be designed such that light incident on it is predominantly transmitted uniformly, and only a small fraction of the light incident on the protective layer is reflected, scattered, or absorbed. The protective layer can also be designed to provide mechanical stability to the image layer. Preferably, the protective layer comprises a plastic film.

[0036] In a preferred embodiment, the reduction layer comprises one or more colorant layers. The colorant layers of the reduction layer can be produced in various ways. In a preferred embodiment, the colorant layers of the reduction layer are produced by applying colorant to the image layer. This offers the advantage that the arrangement of the reduction layer relative to the image layer is very precise, and no gap remains between the reduction layer and the image layer. Furthermore, in this embodiment, the reduction layer and the image layer are firmly bonded together, so that the arrangement cannot be unintentionally altered after the layer system has been created. This allows the layer system to produce an even higher quality HDR image.

[0037] In one embodiment, position markers can assist in the correct alignment of the image layer and the reduction layer relative to each other during the fabrication of the layer system. These position markers could also be called registration marks or alignment marks. For example, an image layer, or a layer associated with the image layer, can be created using position markers. The position markers can then be read in subsequent steps to ensure the correct alignment of the image layer. In one example, a suitable cutting tool, such as a gantry milling machine, can read the position markers using an optical recognition system and then cut the image layer with high accuracy. A cut image layer can then be aligned against fixed stops for further steps, such as applying colorant to the image layer to create the reduction layer.

[0038] As described above, the creation of the colorant layers by applying colorants can also include the application of other components of the colorant layer, for example, the application of mixtures that may contain colorants, binders, solvents, additives, and fillers. The application of colorants to create the colorant layers of the reduction layer is preferably carried out using a digital printing process. Examples of suitable digital printing processes are electrophotography, toner printing, inkjet printing, and dye-sublimation. Dye-sublimation is particularly suitable for printing on transparent substrates, such as a transparent image carrier layer. The application of colorants to create the colorant layers of the reduction layer can also be carried out using screen printing.

[0039] Creating the colorant layers by applying colorants using the aforementioned digital printing processes is advantageous because these processes allow for the application of very black, i.e., highly light-absorbing, colorants. Furthermore, these processes offer precise control over the amount of colorant applied. This enables an even higher dynamic range and thus an even higher quality of the image produced by the layer system.

[0040] Preferably, the colorant layers of the reduction layer are produced by applying colorants using an inkjet printing process and UV-curing inks. The inkjet printing process for applying the colorants is preferably carried out using a flatbed printer. Such an inkjet printing process using a flatbed printer is advantageous because the substrate to be printed does not need to be moved during the printing process, thus allowing, for example, the positioning of the substrate to be maintained with high accuracy during printing. The use of UV-curing ink is advantageous because the ink heats up only slightly during printing, thus minimizing the heat impact on the substrate, while simultaneously achieving high dot sharpness.

[0041] Although in some of the embodiments described above, the colorant layers of the image layer are preferably produced by a photochemical process, they can also be produced by digital printing processes, such as digital printing processes based on electrophotography, toner printing, inkjet printing, or thermal sublimation. Furthermore, the colorant layers of the image layer can be produced by screen printing. Although in the embodiments described above, the colorant layers of the reduction layer are preferably produced by digital printing processes, such as digital printing processes based on electrophotography, toner printing, inkjet printing, or thermal sublimation, they can also be produced by a photochemical process.In a preferred embodiment, the image layer support layer has a front and a back side, wherein the colorant layers of the image layer are arranged on the front side of the image layer support layer, and the colorant layers of the reduction layer are arranged on the back side of the image layer support layer. This has the advantage that the colorant layers of the image layer and the colorant layers of the reduction layer are separated from each other by the image layer support layer. This prevents unwanted interactions between the colorant layers of the image layer and the colorant layers of the reduction layer, which could potentially impair the quality of the colorant layers. Thus, an HDR image of even higher quality can be generated by the layer system.In another embodiment, the image layer support layer also has a front and a back, but the colorant layers of the image layer and the colorant layers of the reduction layer are arranged on the back of the image layer support layer. For example, the colorant layers of the image layer can be applied directly to the back of the image layer support layer, and the colorant layers of the reduction layer can be applied directly to the colorant layers of the image layer. Thus, the colorant layers of the image layer and the colorant layers of the reduction layer can be located close to each other or even directly on top of each other.Furthermore, the arrangement of the colorant layers of the image layer and the reduction layer on the same side of the image layer support layer offers the advantage that both the image layer and the reduction layer can be protected from unintentional damage by the image layer support layer on at least one side.

[0042] In one embodiment, the reduction layer comprises a reduction layer support layer, wherein the colorant layers of the reduction layer are produced by applying colorant to the reduction layer support layer. The reduction layer support layer is not part of the image layer. This embodiment offers the advantage that the reduction layer and the image layer can be produced separately, thus preventing any unwanted interference with one layer during the production of the other. In particular, highly suitable methods can be used for producing both the image layer and the reduction layer, without the choice of a method for producing the image layer significantly restricting the choice of a method for producing the reduction layer, or vice versa. Furthermore, the reduction layer support layer can be optimized for the production of the reduction layer.For example, the reducer layer carrier layer may be better suited for applying colorant to create the colorant layers of the reducer layer than other layers of the layer system, particularly the image layer. This can further improve the quality of an HDR image generated by the layer system. In the embodiment described here, the image layer and / or the reducer layer preferably include positioning markers. These positioning markers can assist in the correct alignment of the image layer and the reducer layer relative to each other during the fabrication of the layer system. This offers the advantage that the reducer layer and the image layer can be fabricated separately and only then aligned relative to each other, thus reducing the need for less precise arrangement of the corresponding colorant layers during the fabrication of the image layer and the reducer layer.

[0043] The reducing layer support layer can, for example, comprise a plastic film, in particular a transparent polyethylene-based plastic film. Alternatively or additionally, the reducing layer support layer can comprise a layer of polymethyl methacrylate. In particular, the reducing layer support layer can comprise a polymethyl methacrylate sheet.

[0044] In embodiments where the reduction layer has a reduction layer support layer, the image layer and the reduction layer can be bonded together. In particular, the image layer and the reduction layer can be bonded together over a surface area, for example, by adhesive bonding the two layers. For this surface bonding, a double-sided adhesive film, in particular a double-sided adhesive film comprising an acrylate layer or a pure acrylate layer, can be arranged between the image layer and the reduction layer. The surface bonding of the image layer and the reduction layer can also be achieved with an acrylate layer, in particular a pure acrylate layer, transparent silicone, or UV-curing adhesive. Especially when the image layer and the reduction layer are bonded together over a surface area, positioning markers can assist in the correct alignment of the image layer and the reduction layer relative to each other.In such embodiments, it can also be advantageous to bond the image layer and the reduction layer with a UV-curing adhesive that, after the image layer and the reduction layer are joined, allows for precise alignment of the position markers relative to each other before curing under UV light. A full-surface bond between the image layer and the reduction layer can also be achieved only in partial areas of the image layer and the reduction layer, for example, in an edge region or in the corners. Alternatively or additionally to a full-surface bond between the image layer and the reduction layer, the image layer and the reduction layer can also include perforations, for example, in the form of holes, through which pins or connecting bolts are inserted to ensure correct alignment of the image layer and the reduction layer relative to each other.An advantage of joining by means of punches and corresponding pins or connecting bolts is that the image layer and the reduction layer are detachably connected. When the image layer and the reduction layer are joined, the colorant layers of the reduction layer are preferably arranged between the reduction layer support layer and the image layer. However, the colorant layers of the reduction layer can also be arranged on the side of the reduction layer support layer that faces the image layer. If, in this embodiment, the image layer comprises an image layer support layer and colorant layers, the colorant layers of the image layer can be arranged between the reduction layer and the image layer support layer. However, the colorant layers of the image layer can also be arranged on the side of the image layer support layer that faces the reduction layer.

[0045] Although in some of the embodiments described above the reducing layer was created by applying colorants to the image layer, the image layer can also be created by applying colorants to the reducing layer. In one embodiment, the reducing layer comprises a reducing layer support layer, wherein the image layer comprises one or more colorant layers, the colorant layers of the image layer being created by applying colorants to the reducing layer. This offers the advantage that the arrangement of the image layer relative to the reducing layer is very precise and, moreover, no gap remains between the reducing layer and the image layer. Furthermore, in this embodiment, the reducing layer and the image layer are firmly bonded together, so that the arrangement cannot be unintentionally altered after the layer system has been created.For example, the colorant layers of the image layer can be printed onto the reduction layer using one of the printing processes mentioned above.

[0046] In one embodiment, the thickness of the colorant layers of the reducing layer is spatially inhomogeneous perpendicular to the plane formed by the reducing layer. For example, in an area where the intensity of light passing through the reducing layer is to be reduced more, the thickness of the colorant layers can be greater than in areas where the intensity of light passing through the reducing layer is to be reduced less. Particularly when the colorant layers are created by applying colorant, the thickness of the colorant layers can be spatially inhomogeneous. The desired thickness of the colorant layers can be achieved during application by the amount of colorant applied and / or by applying the colorant in multiple layers or steps.By simply increasing the thickness of the colorant layers of the reducing layer, the intensity of light passing through the reducing layer can be reduced almost arbitrarily. This offers the advantage that a layer system can be created with less effort, producing an HDR image with a large dynamic range when light passes through the layer system. In one embodiment, the reducing layer comprises a reducing layer support layer, wherein the colorant layers of the reducing layer were produced by a photochemical process. Preferably, in this embodiment, the reducing layer comprises a reducing layer support layer, wherein the colorant layers of the reducing layer were produced by exposing one or more photosensitive layers applied to the reducing layer support layer and subsequently developing them. Corresponding photochemical processes are described in detail below.

[0047] In a preferred embodiment, the colorant layers of the reducing layer comprise only one type of colorant composition. In this embodiment, the reducing layer could also be referred to as a monochrome reducing layer. The advantage of a monochrome reducing layer is that it can be produced with minimal effort. Preferably, in this embodiment, the colorant composition is configured such that the colorant layers of the reducing layer reduce the intensity of light passing through them to a good approximation, independent of the wavelength of the light. For example, the colorant layers of the reducing layer could comprise a black colorant composition and therefore appear in shades of gray under white light, depending on the amount of colorant applied.

[0048] In one embodiment, the colorant layers of the reducing layer comprise several types of colorant compositions. These colorant compositions can be configured, for example, such that the respective colorant layers of the reducing layer reduce the intensity of light passing through them to varying degrees, depending on the wavelength of the light. In this embodiment, the reducing layer could therefore also be referred to as a polychrome reducing layer. The advantage of a polychrome reducing layer is that the intensity distribution generated when light passes through the reducing layer and the image layer can correspond even more precisely to the intended intensity distribution of the image to be produced. The quality of the image produced by the layer system can therefore be further enhanced.

[0049] In one example, the intended intensity distribution in a region of the image to be generated might have a high proportion of red light with a wavelength in the range of 650 nm to 780 nm and a very low proportion of light with a wavelength of less than 650 nm. In this example, the image layer might be designed such that when the image layer is illuminated with white light, the intensity distribution produced as the light passes through the layer does not correspond to this intended intensity distribution, since the image layer alone cannot sufficiently reduce the intensity of light with a wavelength of less than 650 nm.However, the polychrome reducing layer could be designed in such a way that when the layer system is illuminated with white light, the intensity distribution generated when the light passes through the reducing layer and the image layer corresponds to a good approximation of the intended intensity distribution, since the polychrome reducing layer can sufficiently reduce the intensity of light with a wavelength of less than 650 nm.

[0050] In one embodiment, the image layer has a first spatial resolution, and the reduction layer has a second spatial resolution, the first spatial resolution being higher than the second. As described above, the image layer's primary function is to reproduce fine structures and details of the image to be generated by the layer system by varying the intensity of the light passing through it. It is therefore advantageous for the image layer to have the highest possible spatial resolution. However, areas or structures in a generated image that are close together, particularly in the reproduction of photographs, often exhibit similar brightness. In these cases, the brightness of the reproduced image can therefore be adjusted with a lower spatial resolution without noticeably reducing the image quality.The primary function of the reducing layer is to increase the dynamic range of the image produced by the layer system by adjusting the intensity of the light passing through it. Therefore, in many cases, the reducing layer can have a lower spatial resolution than the image layer without noticeably impairing the quality of the image produced by the layer system. A reducing layer with lower spatial resolution has the advantage that it does not need to be optimized for achieving the highest possible spatial resolution, but can instead be designed to achieve the largest possible dynamic range.

[0051] The layer system is preferably designed to display an HDR image, wherein the image layer can be configured such that when light passes through only the image layer, i.e., not through the reduction layer, the image is generated as an SDR image, and wherein the reduction layer is configured such that when light passes through both the image layer and the reduction layer, the image is generated as an HDR image. In one example, the reduction layer is based on a comparison factor image or a gain map as described below. In this case, too, the image layer can include an image layer support layer, wherein the image layer support layer comprises a sheet of polymethyl methacrylate, also known as acrylic glass.In one embodiment, the image layer support layer can be formed solely by a single sheet of polymethyl methacrylate, or it can additionally comprise one or more further layers, for example one or more layers that improve the adhesion of colorant layers to the polymethyl methacrylate sheet.

[0052] Furthermore, the above-mentioned task is solved by a display device for displaying images using a layer system, wherein the display device comprises:

[0053] A transmission unit configured to provide light and a holding unit configured to receive the layer system, wherein the transmission unit and the holding unit are configured and arranged such that the provided light passes through the reducing layer and the image layer of the layer system when the layer system is received by the holding unit. The layer system may, in particular, be one of the embodiments of a layer system described above.

[0054] The display device is designed to provide light and to arrange the layer system relative to the provided light in such a way that the provided light passes through the reducing layer and the image layer of the layer system. As described above, the image to be displayed is generated by the passage of light through the layer system. The display device therefore makes it possible to generate a high-resolution HDR image with a large dynamic range using a layer system designed as described above, with minimal effort and in high quality.

[0055] The X-ray unit of the display device is designed to provide light. The X-ray unit may, for example, be designed to generate light itself. However, the X-ray unit may also be designed to provide light generated by another light source.

[0056] In a preferred embodiment, the transmission unit comprises an active light source. In this embodiment, the provided light is generated by the active light source, which is part of the transmission unit. The advantages of this embodiment are that the light provided by the transmission unit can be optimized for generating an HDR image, and that an HDR image can be generated independently of the availability or quality of an external light source. The light provided by the transmission unit can strike the layer system directly, so that, for example, the provided light strikes the reducer layer and / or the image layer directly. However, the light provided by the transmission unit can also first strike another object before striking the reducer layer and / or the image layer.In particular, the light provided by the fluorescence unit can interact with another object and, in doing so, be scattered and / or partially transmitted. For example, the light provided by the fluorescence unit may first strike another part of the display device, be partially scattered and partially transmitted by that part, and then strike the layer system. The light provided by the fluorescence unit may also strike a layer of the layer system that is not the image layer or the reduction layer, if the layer system includes other layers besides the image layer and the reduction layer. The light provided by the fluorescence unit may also be scattered or otherwise deflected by the layer of the layer system that is not the image layer or the reduction layer before it strikes the reduction layer or the image layer.It should therefore be understood that the essential direction of propagation of the light initially provided by the transmission unit is not necessarily directed towards the reducing layer and / or image layer. The light initially provided by the display device can, for example, be deflected towards the reducing layer and / or image layer by an interaction with another object, in particular by scattering and / or reflection.

[0057] The holding unit of the display device is designed to accommodate the layer system. Preferably, the holding unit is designed such that the layer system can be secured in the display device by means of the holding unit. The holding unit can secure the layer system in the display device directly or indirectly. For example, the holding unit can be designed such that the layer system can be inserted into it and secured by a clamping device. If the clamping device exerts a clamping effect directly on the layer system, this would be an example of direct securing of the layer system by the holding unit. However, it is also conceivable that the holding unit does not act directly on the layer system to secure it in the display device.In one example, the layer system can be applied to a substrate, which can be secured by the holding unit, for instance, using a clamping device. If the clamping device of the holding unit exerts a clamping effect only or predominantly on the substrate, this would be an example of indirect fastening. In another example, the layer system can be arranged between further layers, which in turn are secured by the holding unit, without the holding unit acting directly on the layer system. This, too, would be an example of indirect fastening of the layer system by the holding unit. Indirect fastening by the holding unit offers the advantage that the layer system can be attached to a mechanically stable substrate or arranged between further mechanically stable layers, thereby reducing the risk of unintentional damage to the layer system.

[0058] Preferably, the transmission unit generates white light by means of an active light source. Here, white light refers to a mixture of light of different wavelengths, with light of almost all wavelengths within the visible portion of the electromagnetic spectrum being contained within the white light. The provided light therefore makes it possible to generate almost all color tones by attenuating the light passing through the layer system in a wavelength-dependent manner. The active light source of the transmission unit can be based on different principles for light generation. For example, the active light source can comprise a thermal radiator that emits light in the form of blackbody radiation, which also includes visible light. The active light source can also comprise a non-thermal radiator.In some types of non-thermal emitters, atoms or molecules are excited, for example by the input of energy in the form of an electric current or light, and emit light, particularly visible light, when transitioning to the unexcited state. The active light source of the transmission unit can comprise an incandescent lamp, a fluorescent lamp such as a fluorescent lamp or a neon tube, an LED-based light source, an OLED-based light source, or any combination and number of the aforementioned light sources. Preferably, the active light source of the transmission unit comprises one or more LEDs. More preferably, the active light source of the transmission unit comprises one or more white LEDs. It has been shown that the light from LEDs is particularly well suited for generating an HDR image.White LEDs also offer the advantage of emitting predominantly visible light and only small amounts of UV light and / or infrared radiation. High-intensity UV light and / or infrared radiation could impair the durability of the layer system. Preferably, the transmission unit comprises a plurality of active light sources, which may, for example, be arranged in a matrix. In particular, the transmission unit can comprise a plurality of active light sources, each of which may be one or more white LEDs arranged in a matrix.

[0059] In a preferred embodiment, the display device comprises a diffuser unit, wherein the diffuser unit is arranged such that light provided by the fluorescence unit first strikes the diffuser unit, and a portion of this light exiting the diffuser unit then strikes the layer system when the layer system is held by the holding unit, and wherein the diffuser unit is configured to scatter the provided light. In particular, the diffuser unit can be arranged between the fluorescence unit and the layer system. Since the diffuser unit is configured to scatter the light provided by the fluorescence unit, the diffuser unit makes it possible to modify the spatial intensity distribution of the provided light.This allows for more suitable illumination of the layer system for generating an HDR image, resulting in even higher quality of the generated HDR image. The diffuser unit can, for example, be designed as a partially transparent layer. This partially transparent layer can be configured to scatter light incident on the layer predominantly diffusely, i.e., non-directionally, at its surface and / or within its interior. Diffuse scattering of the supplied light at the diffuser unit makes it possible, in particular, to achieve a more uniform spatial intensity distribution in the light incident on the layer system than the originally supplied light.For example, it can be advantageous for generating a high-quality HDR image if the light emerging from the diffuser unit towards the layer system has the same intensity at every point of the diffuser unit and the direction of propagation of the light emerging from the diffuser unit is essentially omnidirectional. In a preferred embodiment, the diffuser unit is designed as a partially transparent layer that is arranged essentially parallel to the layer system when the layer system is held by the holding unit. Preferably, the width and height of the diffuser unit are not smaller than the width and height of the layer system. Preferably, the diffuser unit comprises a sheet of polymethyl methacrylate, also known as acrylic glass. Sheets of polymethyl methacrylate can be designed to exhibit very homogeneous and high scattering.At the same time, polymethyl methacrylate plates can be designed to exhibit advantageous mechanical stability. It has been shown that a polymethyl methacrylate plate is therefore particularly well suited to adapting the light provided by the transmission unit for the generation of an HDR image. In further embodiments, the diffuser unit can alternatively or additionally comprise a layer of opaque white glass, also known as frosted glass, and / or a glass decoration film, also known as frosted glass film, instead of a polymethyl methacrylate plate. In further embodiments, the diffuser unit can alternatively or additionally comprise a diffuser disc with microlenses.

[0060] In a preferred embodiment, the illuminance achieved by the light provided by the transmission unit and scattered by the diffuser unit is spatially uniform within the layer system. Here, the illuminance within the layer system is defined as spatially uniform if the minimum illuminance achieved within the layer system is not less than a predetermined fraction of the maximum illuminance achieved within the layer system. Preferably, the predetermined fraction is not less than 60%, more preferably not less than 80%, and even more preferably not less than 90%. If the illuminance within the layer system is uniform, no unwanted variations in brightness occur in the HDR image generated when light passes through the layer system.It has been shown that the aforementioned deviations between the minimum and maximum illuminance achieved within the layer system enable the generation of a high-quality HDR image. The display device and the layer system can be designed and arranged relative to each other in such a way that spatial variations in illuminance within the layer system are compensated by the reducing layer, so that the desired intensity distribution is generated when light passes through the reducing layer and the image layer. For example, the illuminance achieved by the light provided by the transmission unit could be lower at the edges of the layer system than in the center of the transmission unit.In this example, the reducing layer of the layer system can advantageously be designed such that the intensity of light passing through the reducing layer is reduced less in the corresponding edge regions of the layer system than in the center of the layer system. In another example, the illuminance achieved by the light provided by the transmission unit could be greater in edge regions of the layer system than in the center of the transmission unit. This can be the case, in particular, if the display device is designed to generate edge lighting. In this example, the reducing layer of the layer system can advantageously be designed such that the intensity of light passing through the reducing layer is reduced more in the edge regions of the layer system than in the center of the layer system.The luminance achieved by the display device in the area of ​​the layer system is preferably at least 1000 nits, more preferably 10000 nits, and even more preferably 20000 nits, where: 1 nit = 1 Cd / m. 2The luminance here preferably refers to the maximum luminance. It has been shown that with such a luminance, an HDR image with a large dynamic range can be generated, and this dynamic range can also be perceived by the human eye. Preferably, the display device includes a dimmer unit, wherein the dimmer unit is configured to control the luminance achieved by the display device in the area of ​​the layer system. Preferably, the dimmer unit is configured to control the luminance, in particular automatically, depending on the ambient light. This has the advantage that the large dynamic range of the displayed image can be perceived more easily. For example, the dimmer unit can be configured to reduce the luminance of the display device in a dark environment.In this example, a viewer adapted to low light conditions can perceive the displayed image without being dazzled. Furthermore, the display device consumes less power in this example. Alternatively or additionally, the dimmer unit can be configured to control the luminance based on manual input. For example, when using the display device in a room with consistent lighting conditions, users can set the luminance once without it needing to be changed again. It is also conceivable that the dimmer unit could be configured to vary the luminance only within a defined range.

[0061] In a preferred embodiment, the transmission unit and the holding unit are designed and arranged such that the supplied light first passes through the reducing layer and then through the image layer of the layer system when the layer system is held by the holding unit. It has been shown that the layer system transmitted in this sequence can produce an HDR image of particularly high quality. Furthermore, the advantage arises that the intensity of the light striking the image layer is already partially reduced during its passage through the reducing layer, thereby slowing the fading of the colorant layers of the image layer. The preferred embodiments of the transmission unit include an active light source. However, embodiments are also conceivable in which the transmission unit is configured to supply light generated by another light source.In such embodiments, the transmission unit is preferably further configured to modify the light generated by another light source. The light modified by the transmission unit is preferably better suited for generating an HDR image than the light originally generated by the light source. For example, the light modified by the transmission unit can have a different spectral or spatial intensity distribution than the light originally generated by the other light source. A suitable alternative light source could be, for example, the sun. Sunlight could be provided and modified by the transmission unit in such a way that it is suitable for illuminating the layer system and generating an HDR image. For this purpose, the transmission unit can, for example, include components such as mirrors, lenses, optical filters, etc.In particular, if the X-ray unit provides light from another light source, the display device preferably includes a diffuser unit.

[0062] Furthermore, the above-mentioned task is solved by a method for producing a layer system for displaying images, the method comprising the following steps:

[0063] Providing image data for the image layer,

[0064] Providing reduction data for the reduction layer,

[0065] Generating the image layer based on the provided image data, and generating the reduction layer based on the provided reduction data. The resulting layer system can, in particular, be one of the embodiments of a layer system described above.

[0066] Providing image data generally involves providing the information needed to generate the image layer. Specifically, the image data defines the image to be generated by the image layer when light passes through it. The image data can, for example, be contained in an image file. In particular, the image data can be structured to represent the corresponding image content for each region of the image to be generated by the image layer as a number or sequence of numbers. For example, the image data can represent the image to be generated by the image layer as a raster graphic divided into a multitude of pixels. In this case, the image data can represent the corresponding image content for each pixel of the image to be generated by the image layer as a number or sequence of numbers, where each number or sequence of numbers refers to a point in a color space.The numbers associated with a pixel in the image data could therefore also be called color values. The pixels associated with a color value could also be called pixels. Preferably, the image data defines the image to be produced by the image layer when light passes through it as a multitude of pixels. The pixels of the image data can, for example, refer to a point in a color space that defines a hue, a saturation, and a brightness.

[0067] Providing reduction data generally involves providing the information needed to generate the reduction layer. Specifically, the reduction data defines the image to be generated by the reduction layer when light passes through it. The reduction data can be contained, for example, in an image file. In particular, the reduction data can be structured to represent the corresponding image content as a number or sequence of numbers for each region of the image to be generated by the reduction layer. For example, the reduction data can represent the image to be generated by the reduction layer as a raster graphic divided into a multitude of pixels. The pixels of the reduction data can, for example, refer to a point in a color space that defines a hue, saturation, and brightness.In particular, if the reduction data is to be used to create a monochrome reduction layer, the pixels of the reduction data can also refer to a point in a reduced color space that defines only shades of gray.

[0068] The image data and the reduction data can each be contained in image files, where image files are files containing digital information about an image to be reproduced. Image files can be encoded in a variety of file formats. Preferably, the image data and / or reduction data are contained in image files encoded in one or more of the following file formats: JPEG, JPEG XL, AVIF, TIFF, HEIF, PNG. The image files can also be encoded in so-called raw data formats. Raw data formats refer to different encodings, often defined by camera manufacturers, and the corresponding files are often called RAW files. The image files can also be encoded in standardized raw data formats, such as the DNG format.

[0069] It should be understood that the image data and the reduction data can also be contained in the same image file. It should further be understood that the provided image data can include information that relates directly or indirectly to the reduction layer. Conversely, the provided reduction data can also include information that relates directly or indirectly to the image layer. For example, the provided image data and the provided reduction data can contain information about the arrangement of the image layer and the reduction layer relative to each other. For example, the provided image data and / or the provided reduction data can contain information about position markers to be generated, where the position markers may be designed to assist in the correct alignment of the image layer and the reduction layer relative to each other during the fabrication of the layer system.In one embodiment, the reduction data is identical to the image data. In this case, providing the image data and providing the reduction data can occur in the same step.

[0070] Since the image data defines the image to be generated by the image layer when light passes through it, the dynamic range representable by the image data can be smaller than the dynamic range of the image to be generated by the layer system. For example, the dynamic range representable by the image data can correspond to the dynamic range of SDR images. In a corresponding embodiment, the image data could therefore also be referred to as SDR image data.

[0071] In addition to image data and reduction data, high-contrast image data can also be provided for the layer system. This high-contrast image data defines the image to be generated by the layer system when light passes through it. The high-contrast image data can, for example, be contained in an image file. In particular, the high-contrast image data can be structured such that it represents the corresponding image content for each area of ​​the image to be generated by the layer system as a number or sequence of numbers. For example, the high-contrast image data can represent the image to be generated by the layer system as a raster graphic divided into a multitude of pixels. Preferably, the high-contrast image data defines the image to be generated by the layer system as a multitude of pixels.The pixels of the high-contrast image data can, for example, refer to a point in a color space that defines a hue, saturation, and brightness. The high-contrast image data is designed to represent a greater dynamic range than the image data, i.e., than the SDR image data. For example, the dynamic range representable by the high-contrast image data can correspond to the dynamic range of HDR images. In a corresponding embodiment, the high-contrast image data could therefore also be referred to as HDR image data. Preferably, the dynamic range representable by the high-contrast image data corresponds to the dynamic range of the image to be generated by the layer system. In a preferred embodiment of the method for producing a layer system for displaying images, the method comprises:

[0072] Providing high-contrast image data for the layer system,

[0073] providing reduction data for the reduction layer includes:

[0074] Generating reduction data based on a comparison of the provided image data and the provided high-contrast image data.

[0075] As described above, the image data defines the image to be generated by the image layer, while the high-contrast image data defines the image to be generated by the layer system. For the interaction of the image layer and the reduction layer to produce a high-quality HDR image, the reduction layer must adjust the brightness of the generated image to precisely the right degree. This can be achieved by generating the reduction data based on a comparison of the provided image data and the provided high-contrast image data. This has the advantage that the reduction data can be even better matched to the image data. The resulting layer system can therefore produce an HDR image of even higher quality.

[0076] A comparison of the image data and the high-contrast image data can, for example, involve comparing the brightness levels defined by the image data with those defined by the high-contrast image data. Such a comparison can be performed for each point of the image to be generated. If the image data and the high-contrast image data contain color information in addition to brightness, a comparison can also include a comparison of the color information. In one example, the image data and the high-contrast image data are each stored in an image file and contain color information encoded in color channels. In each color channel of the image data, a brightness level can be encoded for each point of the image defined by the image data. Similarly, in each color channel of the high-contrast image data, a brightness level can be encoded for each point of the image defined by the high-contrast image data.In this example, a comparison of the image data and the high-contrast image data can be a comparison of the brightness at each point of the image to be generated and for each color channel.

[0077] In a preferred embodiment, the image data and the high-contrast image data are each divided into a pixel grid, with coordinates (x,y) assigned to each pixel. In this embodiment, for the comparison of the image data and the high-contrast image data, a comparison factor G(x,y) or several comparison factors Gi(x,y) are preferably assigned to each pixel. In particular, if the image data and the high-contrast image data contain color information encoded in color channels, a comparison factor can, for example, be assigned to each color channel i for each pixel (x,y). For the comparison, the brightness Li(x,y) defined by the image data in each pixel and the brightness l_2(x,y) defined by the high-contrast image data in each pixel are preferably compared. The brightness in a pixel can, for example, refer to a brightness value "Y" of that pixel when using a linear CIE XYZ color space.In another example, the image data can include RGB data, specifically RGB data according to the ITU-R BT.2100-2 standard. If the image data includes RGB data, the brightness in a pixel can, for example, refer to a brightness value "YRGB," which is calculated as a linear combination of a red component R, a green component G, and a blue component B, for example, YRGB = (0.2126 R) + (0.7152 G) + (0.0722 B). If the image data and the high-contrast image data contain color information, the brightness values ​​Li(x,y) and L2,i(x,y) for each color channel i can be compared separately. In one example, the image data can include RGB data, and the brightness in a pixel and for a color channel can refer to a brightness value "YR" of the red component R, a brightness value "YG" of the green component G, or a brightness value "YB" of the blue component G. The comparison factors are preferably calculated as follows:

[0078]

[0079] <>

[0080] and

[0081]

[0082] The parameters A and A2 are small, positive numbers that ensure equations (1) and (2) are not undefined if one of the brightness values ​​is zero. The comparison factors calculated according to equations (1) or (2) are then preferably normalized, for example by mapping to the range [0,1], where, disregarding outliers, the minimum value of G or Gi is mapped to 0 and the maximum value to 1. The comparison factors normalized in this way can then be further mapped to normalized, corrected comparison factors G'(x,y) and Gi'(x,y) using a correction function. For example, the mapping to normalized, corrected comparison factors can be achieved with a gamma correction.The normalized, corrected comparison factors G'(x,y) and Gi'(x,y) are defined for each pixel (x,y) and can therefore be combined to form a comparison factor image, based on which the reduction data is generated. To generate the reduction data based on a comparison factor image, the image can be further processed, for example, by performing another gamma correction. Further processing of the comparison factor image can be particularly advantageous to account for characteristics of the manufacturing process, such as a printing process, and to reduce the distorting effects of the manufacturing process.

[0083] In one example, the intention might be to create a monochrome reduction layer for a layer system used to display an image. Based on the image data and the high-contrast image data, the normalized, corrected comparison factors G'(x,y) can be calculated as described above and combined to form a comparison factor image. The reduction data in this example can correspond to the comparison factor image, so that the reduction layer created based on it essentially generates the comparison factor image when light passes through it. Such a reduction layer can be created, for example, by printing the comparison factor image onto a layer of the layer system, in particular the image layer or a reduction layer support layer. In this embodiment, colorant is preferably applied to a layer of the layer system during printing.In this example, large values ​​for G'(x,y) could be represented by a small application of colorant, and small values ​​of G'(x,y) by a large application of colorant.

[0084] In another example, the intention might be to create a polychrome reduction layer for a layer system to represent an image. Based on the image data and the high-contrast image data, the normalized, corrected comparison factors Gi'(x,y) for each color channel can be calculated as described above and combined to form a comparison factor image. The reduction data in this example can be designed such that the reduction layer created based on it essentially generates the comparison factor image as light passes through it. Such a designed reduction layer can be created, for example, by printing the comparison factor image onto a layer of the layer system, in particular the image layer or a reduction layer support layer.In this embodiment, during printing, several colorants, for example one colorant per color channel, are preferably applied to a layer of the layer system. Large values ​​for Gi'(x,y) could be represented in this example by a small amount of colorant applied, and small values ​​of Gi'(x,y) by a large amount of colorant applied. The comparison factors calculated as described above can be further adjusted. For example, new comparison factors Gi'(x,y) can be generated for each color channel i based on normalized, corrected comparison factors G'(x,y). For this purpose, the comparison factors G'(x,y) can be calculated pixel-wise using color value and saturation information from the image data or the high-contrast image data. The comparison of the image data and the high-contrast image data can also have already been performed during the generation of the image data and / or the high-contrast image data.In one example, the image data and the high-contrast image data are encoded in a single image file. It is possible that such an image file does not directly store both the image data and the high-contrast image data, but rather, for example, only the image data and additional conversion information. Based on the stored conversion information and the image data, the high-contrast image data can be calculated in this example. It is also possible that such a file directly stores only the high-contrast image data and additionally stores conversion information. Based on the stored conversion information and the high-contrast image data, the image data can be calculated in this example. Such conversion information can also be defined pixel-wise for a pixel grid. In particular, the conversion information can include comparison factors calculated according to equations (1) or (2).The comparison factors of the conversion information can also be normalized and / or corrected, as described above. The conversion information can also include a comparison factor image derived from the comparison factors. In this example, the reduction data can be generated based on the conversion information. For instance, the reduction data can be configured such that the reduction layer generated based on it essentially produces the comparison factor image of the conversion information when light passes through it.

[0085] The image layer can be generated in different ways. In one embodiment, the image layer comprises an image layer support layer and one or more colorant layers, wherein the generation of the image layer based on the provided image data includes:

[0086] Providing the image layer support layer and

[0087] Application of colorant to the provided image layer support layer. In this embodiment, the colorant layers of the image layer are created by applying colorant to the provided image layer support layer. Creating the colorant layers by applying colorant can also include applying other components of the colorant layer, for example, applying mixtures that may include colorants, binders, solvents, additives, and fillers. The application of colorant to create the colorant layers of the image layer is preferably carried out using a digital printing process. Examples of suitable digital printing processes are the printing processes already mentioned above, in particular electrophotographic processes, toner printing processes, inkjet printing processes, and thermal sublimation processes.The application of colorant to create the colorant layers of the reduction layer can also be carried out using screen printing. The provided image layer support layer can, for example, comprise a plastic film. In particular, the provided image layer support layer can comprise a polyethylene plastic film. However, it is also possible that the provided image layer support layer comprises a polymethyl methacrylate plate. For example, a polymethyl methacrylate plate can be provided as the image layer support layer.

[0088] Although in some of the embodiments described here the reduction layer is created after the image layer, the image layer can also be created after the reduction layer. In one embodiment, the image layer comprises one or more colorant layers, wherein the creation of the image layer based on the provided image data includes:

[0089] Applying colorant to the reduction layer to create the colorant layers of the image layer. In this embodiment, the colorant layers of the image layer are created by applying colorant to the previously prepared reduction layer.

[0090] In a preferred embodiment, the image layer comprises one or more colorant layers, wherein generating the image layer based on the provided image data includes:

[0091] Generating the colorant layers of the image layer using a photochemical process. More preferably, the image layer comprises an image layer support layer and one or more colorant layers, wherein generating the image layer based on the provided image data includes:

[0092] Providing the image layer support layer, wherein one or more photosensitive layers are applied to the provided image layer support layer, exposing the photosensitive layers and developing the exposed, photosensitive layers.

[0093] In this embodiment, the image layer support layer preferably comprises a plastic film. The image layer support layer can, for example, comprise a polyethylene plastic film. Further layers can be applied to the provided image layer support layer, and these further layers can be modified or removed during the image layer production process.

[0094] In the embodiment described here, one or more photosensitive layers are applied to the provided image-layer support layer. A photosensitive layer refers to a layer that interacts with light incident upon it in such a way that the chemical and / or physical properties of the photosensitive layer change. The photosensitive layers applied to the image-layer support layer can each comprise a photosensitive suspension. Preferably, the suspension contains a support medium and halide crystals, wherein the halide crystals are dispersed in the support medium. Preferably, the photosensitive layers each comprise a support medium and silver halide crystals, such as silver chloride crystals, silver bromide crystals, or silver iodide crystals. The support medium can, for example, be a gelatin-based support medium.The light-sensitive layers can also contain other components. In particular, they can contain components that increase or decrease their sensitivity to light of specific wavelengths. Furthermore, they can contain components designed to generate colorants. An example of such colorants are color couplers. Light-sensitive layers of this type are sometimes also referred to as photoemulsions.

[0095] During exposure of photosensitive layers, the photosensitive layers are exposed to light, which can generally include light of different wavelengths and intensities. The light used for exposure can include visible light, UV light, or infrared radiation. Exposure alters the chemical and / or physical properties of the photosensitive layers. The extent of these changes can depend on the wavelength range of the light used for exposure and / or its intensity within the photosensitive layer. In particular, if several photosensitive layers are applied to the image-sensitive substrate, each with a different wavelength dependency, exposure can be carried out with light from different light sources and / or in several steps.In general, during exposure, each point of the photosensitive layer(s) is exposed to light of a specific wavelength or within a specific wavelength range and intensity. Exposure thus allows the chemical and / or physical properties of the photosensitive layers to change according to the properties of the light used for exposure. The spatial distribution of the chemical and / or physical properties of the exposed photosensitive layers could also be described as a latent image. For example, the photosensitive layers could consist of silver halide crystals and be structured such that, upon exposure to light, the silver ions are partially reduced to silver, forming silver clusters.In this example, the photosensitive layers can contain components other than silver halide crystals, which determine the wavelength dependence of the reaction of silver ions to silver. Depending on the wavelength range and intensity of the light used for exposure in a region of the photosensitive layers, more or fewer silver clusters are formed in that region. The spatial distribution of the silver clusters could be described as a latent image in this example. In a preferred embodiment, the layers deposited on the image-bearing layer are exposed using a laser exposure unit.

[0096] During the development of exposed photosensitive layers, colorant layers are formed from the exposed photosensitive layers. For example, during development, the photosensitive layers can be exposed to chemicals that are formulated to produce colorants, particularly dyes, depending on the chemical and / or physical properties of the photosensitive layers. These chemicals could also be called developers. Development can be carried out in several steps. For example, development may include steps in which chemicals used in previous steps are removed from the photosensitive layers and / or in which the remaining photosensitive components of the photosensitive layers are removed.In one example, the photosensitive layers contain silver halide crystals, and upon exposure, silver clusters are formed depending on the wavelength range and intensity of the incident light. The chemicals used for development in this example can be designed such that colorant is formed in the region of the silver clusters during development. For example, the chemicals used for development can be designed to drastically enlarge the silver clusters formed during exposure. These enlarged silver clusters can absorb and / or scatter visible light, so that, in this example, areas of the exposed and developed photosensitive layers with a high concentration of enlarged silver clusters appear dark when light passes through the photosensitive layers.In this example, the enlarged silver clusters could also be described as colorants, and the exposed and developed photosensitive layer could be described as a colorant layer. In another example, the chemicals used for development are designed such that dyes are formed in the region of the silver clusters during development. For instance, the chemicals used for development and the color couplers contained in the photosensitive layers can be designed such that the chemicals used for development and the color couplers react with each other and / or with the silver contained in the photosensitive layers to form dyes.The dyes produced during development can absorb and / or scatter visible light depending on its wavelength. Therefore, in this example, areas of the exposed and developed photosensitive layers with a high concentration of dye appear colored when white light passes through them. Because they contain dye, these exposed and developed photosensitive layers could also be called colorant layers.

[0097] By combining several light-sensitive layers in which different dyes can be formed, multicolored image layers can be created. Preferably, three light-sensitive layers are applied to the provided image layer support layer, wherein the first layer is configured to form a colorant during development that appears in cyan under white light, wherein the second layer is configured to form a colorant during development that appears in magenta under white light, and wherein the third layer is configured to form a colorant during development that appears in yellow under white light.

[0098] Additional layers may be applied to the provided image carrier layer and / or to the photosensitive layers. For example, an adhesive layer may be placed between the image carrier layer and the photosensitive layers, which improves the adhesion of the photosensitive layers to the image carrier layer. Furthermore, separating layers may be applied between the photosensitive layers to prevent mixing or mutual interaction between the individual photosensitive layers. A protective layer may also be applied to the photosensitive layers, which protects them during the formation of the image layer. Preferably, the protective layer remains on the generated colorant layers, so that the colorant layers continue to be protected from unwanted damage after the image layer has been formed.An antihalation layer can also be applied to the image carrier layer, designed to absorb the light used for exposure. For example, the antihalation layer can be located between the photosensitive layers and the image carrier layer, or on the side of the image carrier layer opposite the photosensitive layers. The antihalation layer prevents unwanted additional exposure of the photosensitive layers by scattered or reflected light. Preferably, the antihalation layer is designed to become transparent or dissolve during the development of the photosensitive layers.

[0099] The generation of the reduction layer can be carried out in different ways. In one embodiment, the reduction layer comprises a reduction layer carrier layer and one or more colorant layers, wherein the generation of the reduction layer based on the provided reduction data includes:

[0100] Providing the reduction layer carrier layer and

[0101] Application of colorant to the reduction layer carrier layer.

[0102] In this embodiment, the colorant layers of the reduction layer are created by applying colorant to the provided reduction layer carrier layer.

[0103] As described above, the creation of the colorant layers by applying colorants can also include the application of other components of the colorant layer, such as mixtures containing colorants, binders, solvents, additives, and fillers. The application of colorants to create the colorant layers of the reduction layer is preferably carried out using a digital printing process. Examples of suitable digital printing processes include electrophotography, toner printing, inkjet printing, and dye sublimation. The application of colorants to create the colorant layers of the reduction layer can also be carried out using screen printing.

[0104] In some embodiments of the method, the image layer and the reduction layer are produced separately. In such embodiments, the method for producing a layer system preferably further comprises: bonding the produced reduction layer with the produced image layer.

[0105] Preferably, the reduction layer and the image layer are bonded together over their entire surface. For example, the reduction layer and the image layer can be glued together over their entire surface.

[0106] In a preferred embodiment of the method, the reduction layer comprises one or more colorant layers, wherein generating the reduction layer based on the provided reduction data comprises:

[0107] Application of colorant to the image layer to create the colorant layers of the reduction layer.

[0108] In this embodiment, the colorant layers of the reduction layer are created by applying colorant to the image layer.

[0109] As described above, the creation of the colorant layers by applying colorants can also include the application of other components of the colorant layer, such as mixtures containing colorants, binders, solvents, additives, and fillers. The application of colorants to create the colorant layers of the reduction layer on the image layer is preferably carried out using a digital printing process. Examples of suitable digital printing processes include electrophotography, toner printing, inkjet printing, and dye sublimation. The application of colorants to create the colorant layers of the reduction layer can also be carried out using screen printing.

[0110] Particularly when generating the reduction layer based on the provided reduction data involves applying colorant to the image layer to create the colorant layers of the reduction layer, ensuring accurate color reproduction of both the image layer and the reduction layer can be challenging. Therefore, in one embodiment of the method for producing a layer system for displaying images, the method further includes creating a color profile for generating the image layer and / or for generating the reduction layer. Creating a color profile could also be referred to as profiling. The created color profile can be, for example, an ICC profile or an ICC Device Link profile. Preferably, a first color profile is created for generating the image layer and a second color profile is created for generating the reduction layer.In one example, a first color profile for creating the image layer, i.e., for applying colorant layers to an image layer support layer, could be created using standard methods. In another example, a second color profile for creating the reduction layer could be created using standard methods. It would also be conceivable to create a single color profile for creating both the image layer and the reduction layer.

[0111] In one embodiment, the image data and / or the reduction data include information about position markers to be generated. The position markers are preferably designed to assist in the correct alignment of the image layer and the reduction layer relative to each other during the fabrication of the layer system. In a preferred embodiment, the image data includes information about position markers to be generated, wherein generating the image layer based on the provided image data comprises:

[0112] Generating colorant layers of the image layer based on the provided image data, wherein the colorant layers of the image layer include the position markers to be generated. In this embodiment, the position markers can be generated as part of the generated colorant layers of the image layer. The alignment of the position markers relative to other structures of the image layer can therefore be very precise. Preferably, in this embodiment, generating the reduction layer based on the provided reduction data includes:

[0113] Reading the position markers of the image layer,

[0114] Aligning the image layer based on the read position markers and generating color medium layers of the reduction layer on the aligned image layer. Reading the position markers and aligning the image layer based on these markers has the advantage that the color medium layers of the reduction layer can be generated on the image layer in such a way that the alignment of the image layer and the reduction layer relative to each other is very precise. The layer system thus created can therefore produce an HDR image of even higher quality. For example, an image layer can first be created that includes position markers as part of the generated color medium layers. These color medium layers can be generated, for example, using one of the methods described above, in particular a photochemical process.For generating the colorant layers of the image layer, a first tool or group of tools can be used. Particularly if the image layer thus generated needs to be moved before generating the reduction layer—for example, because a second tool or group of tools is used to generate the reduction layer, or because the colorant layers of the reduction layer are not positioned on the same side of the image layer as the colorant layers of the image layer—position markers of the image layer can be read in, and the image layer can be aligned based on these markers before generating the colorant layers of the reduction layer. This alignment of the image layer based on the read position markers can, for example, be performed directly within a tool for generating the colorant layers of the reduction layer.However, it is also conceivable that the position markers are read in a cutting unit, for example, a gantry milling machine, and the image layer is cut based on the read position markers, particularly with high precision. The image layer cut in this way can then be aligned against stops, especially against stops of a tool for generating the colorant layers of the reduction layer on the image layer. For example, an image layer cut with high precision based on the read position markers can be aligned against stops of a flatbed printer, the flatbed printer being designed to apply colorants for generating the colorant layers of the reduction layer.

[0115] In one embodiment of the method, the creation of the image layer comprises:

[0116] Providing a layer for forming an image layer support layer, generating colorant layers on the layer for forming an image layer support layer, wherein the colorant layers in a first region of the layer for forming an image layer support layer correspond to the colorant layers of the image layer and in a second region of the layer for forming an image layer support layer comprise position markers,

[0117] Reading the position markers on the layer to form an image layer support layer, and

[0118] The layer for forming an image layer support layer is cut to the first area of ​​the layer for forming an image layer support layer. Preferably, the layer for forming an image layer support layer is cut based on the read position markers. Preferably, the first area of ​​the layer for forming an image layer support layer is different from the second area of ​​the layer for forming an image layer support layer, so that the generated image layer no longer includes position markers after cutting. An image layer generated in this way can be cut with high accuracy. This has the advantage that for subsequent steps, for example, for applying colorants to the image layer to generate the reduction layer, the image layer can be aligned with high accuracy, for example, against stops. At the same time, the position markers are no longer part of the generated image layer in this embodiment.

[0119] Although in some of the embodiments described above the image layer includes position markers, the reduction layer can alternatively or additionally include position markers. This is particularly advantageous in embodiments in which the reduction layer is created before the image layer. The above descriptions regarding the creation and use of the position markers can then apply accordingly, with the roles of the reduction layer and the image layer being reversed.

[0120] Furthermore, the above-mentioned task is solved by a reduction layer for use with an image layer, wherein the image layer is designed such that when light passes through the image layer, an image with a first intensity distribution is generated.

[0121] the reducing layer is partially transparent to light,

[0122] wherein the reducing layer is configured to reduce the intensity of light passing through the reducing layer such that when light passes through the reducing layer and the image layer, the image is produced with a second intensity distribution, wherein a difference between the greatest intensity of the first intensity distribution and the smallest intensity of the first intensity distribution is smaller than the difference between the greatest intensity of the second intensity distribution and the smallest intensity of the second intensity distribution.

[0123] In particular, the reduction layer can be configured to interact with an image layer in such a way that one of the embodiments of the layer system described above is created.

[0124] According to a further aspect of the invention, a layer system for displaying images, in particular for displaying high-contrast images, is provided, wherein the layer system is configured such that an image is generated when light passes through the layer system, wherein the layer system comprises: an image layer, wherein the image layer is configured such that when light passes through the image layer, the image is generated with a first intensity distribution,

[0125] a reducing layer, wherein the reducing layer is configured to reduce the intensity of light passing through the reducing layer in such a way that when light passes through the reducing layer and the image layer, the image is produced with a second intensity distribution.

[0126] In this layer system, the image layer and / or the reduction layer can also be configured as described above. In particular, the difference between the highest intensity and the lowest intensity of the first intensity distribution can be smaller than the difference between the highest intensity and the lowest intensity of the second intensity distribution.

[0127] It should be understood that the described layer systems, the presentation device, the method for producing a layer system and the reduction layer itself may have similar or identical embodiments, as defined in particular in the dependent claims.

[0128] In the following, embodiments of the invention are described with reference to the following figures, wherein

[0129] Fig. 1 schematically and exemplarily shows a display device for displaying images using a layer system for displaying images with a corresponding layer system,

[0130] Fig. 2a schematically and exemplarily shows a layer system for displaying images,

[0131] Fig. 2b schematically and exemplarily shows an enlarged section of the layer system shown in Fig. 2a,

[0132] Fig. 3 schematically and exemplarily shows a section through another embodiment of a layer system for displaying images,

[0133] Fig. 4 schematically and by way of example shows a section through another embodiment of a layer system for displaying images, Fig. 5 schematically and by way of example shows another embodiment of a display device for displaying images by means of a layer system,

[0134] Fig. 6 shows a flowchart for a process for producing a layer system for displaying images,

[0135] Fig. 7 shows a flowchart for an embodiment of a method for producing a layer system for displaying images,

[0136] Fig. 8a schematically and exemplarily shows an embodiment of an image layer support layer with photosensitive layers for producing colorant layers,

[0137] Fig. 8b schematically and exemplarily shows the image layer support layer shown in Fig. 8a with the colorant layers produced by exposure and development,

[0138] Fig. 9 schematically and exemplarily shows another embodiment of a display device for displaying images using a layer system,

[0139] Fig. 10 schematically and exemplarily shows the display device from Fig. 9 in the open state,

[0140] Fig. 11 schematically and exemplarily shows a sectional view of the display device from Figures 9 and 10,

[0141] Fig. 12a schematically and by way of example shows another embodiment of a display device for displaying images by means of a layer system for displaying images with a corresponding layer system, Fig. 12b schematically and by way of example shows a sectional view of the display device of the layer system from Fig. 12a,

[0142] Fig. 12c schematically and exemplarily shows an enlarged section of the sectional view shown in Fig. 12b,

[0143] Fig. 13 schematically and exemplarily shows a section through another embodiment of a layer system for displaying images, and Fig. 14 schematically and exemplarily shows a section through another embodiment of a layer system for displaying images.

[0144] Fig. 1 shows schematically and by way of example a display device 1 for displaying images by means of a layer system for displaying images together with a corresponding layer system 2.

[0145] The display device 1 comprises a transmission unit 3, a diffuser unit 6, and a holding unit 4. The transmission unit 3 is configured to provide light 5. In the embodiment shown here, the transmission unit includes an active light source for this purpose. The holding unit 4 is configured to receive the layer system and, in the exemplary embodiment shown here, comprises two clamping rails 41, 42 that receive the layer system 2 and hold it by their clamping action. In this embodiment, the holding unit 4 is thus designed for the direct attachment of the layer system. The transmission unit 3, the diffuser unit 6, and the holding unit 4 are configured and arranged such that the provided light 5 passes through the diffuser unit 6 and the layers of the layer system 2 when the layer system 2 is received by the holding unit 4.

[0146] The layer system 2 is designed such that an image is generated when light 5 passes through it. The layer system 2 is therefore not completely transparent, but rather modifies the intensity distribution of the supplied light 5 in such a way that the light 5' passing through the layer system 2 produces the image to be generated. A viewer 7 looking at the display device 1 and the layer system 2 can perceive the image thus generated. In the exemplary embodiment shown here, the generated image reproduces a photograph, the photograph showing a tree in a meadow, a section of the sky, and the sun.

[0147] The generated image can exhibit high brightness because the active light source may be designed to provide light 5 at high intensity. Regions of layer system 2 may be designed such that the portion of the provided light that has passed through layer system 2 still exhibits high intensity. For example, the region of layer system 2 representing the sun and the portion of the sky may be designed to absorb only a small amount of the provided light 5. This region therefore appears very bright to the viewer 7. The region of layer system 2 representing the tree and the meadow may be designed to absorb the provided light 5 strongly. This region appears-M -

[0148] Therefore, 7 appears dark to the viewer. The greater the difference between the highest and lowest brightness of the image, the greater the dynamic range of the image.

[0149] To produce an image with the largest possible dynamic range perceptible to humans, it is advantageous for the bright areas of the image to appear very bright, which can be achieved with a suitably designed transmission unit 3. However, it is also necessary that the layer system 2 be able to reduce the intensity of the light passing through the layer system 2 as much as possible in the dark areas of the image. Figures 2a and 2b show the suitably designed layer system 2 in more detail. The layer system 2 comprises two layers: an image layer 21 and a reduction layer 22.

[0150] The image layer 21 is configured such that when light passes through it, an image with a first intensity distribution would be generated. The reduction layer 22 is configured to reduce the intensity of light passing through it such that when light passes through both the reduction layer 22 and the image layer 21, an image with a second intensity distribution is generated. Furthermore, the image layer 21 and the reduction layer 22 are configured such that the difference between the highest and lowest intensities of the first intensity distribution is smaller than the difference between the highest and lowest intensities of the second intensity distribution.The maximum achievable brightness differences that can be reached when light passes through the image layer 21 alone are therefore smaller than the maximum achievable brightness differences that can be reached when light passes through the reducing layer 22 and the image layer 21. The dynamic range of the image produced when light passes through the reducing layer 22 and the image layer 21 is therefore greater than the dynamic range that could be achieved when light passes through the image layer 21 alone.

[0151] The increased dynamic range is achieved by the reducing layer 22, which is specifically designed to absorb light very strongly in some areas and very little in others. The image to be generated by layer system 2 shows a tree in a meadow against a section of the sky and the sun. In the area 29 of layer system 2 that represents the meadow, the reducing layer 22 is configured to strongly reduce the intensity of the light striking the layer system. In the area 28 of layer system 2 that represents the sun, the reducing layer 22 is configured to only weakly reduce the intensity of the light striking the layer system. This results in a large difference in brightness between area 28 and area 29. In particular, the difference in brightness between area 28 and area 29 would be significantly smaller without the reducing layer 22.

[0152] The image layer 21 and the reduction layer 22 can each be composed of several sub-layers. Fig. 2b schematically shows an enlarged section of the layer system 2, so that individual layers can be seen more clearly.

[0153] In the exemplary embodiment shown here, the image layer 21 comprises an image layer support layer 211 made of polyethylene. In this embodiment, the image layer support layer 211 could also be referred to as a plastic film. The image layer support layer 211 has little influence on the optical properties of the image layer 21, as it predominantly transmits light incident on the image layer support layer 211 and reflects, scatters, or absorbs only a small portion of the light. The image layer support layer 211 is designed to provide mechanical stability to the image layer. Alternatively, the image layer 21 could also comprise an image layer support layer made of polymethyl methacrylate. For example, the image layer support layer could be designed as a polymethyl methacrylate sheet.

[0154] The image layer support layer 211 has a front and a back. Colorant layers 212 of the image layer 21 are arranged on the front of the image layer support layer 211. The colorant layers 212 contain colorants that determine the optical properties of the colorant layers 212. In particular, the colorant layers are designed to transmit, scatter, or absorb light depending on the wavelength. In the embodiment shown here, the colorant layers 212 comprise three individual layers, the individual layers differing in particular in the type and concentration of the colorants they contain. The first layer contains a colorant that appears cyan under white light, the second layer contains a colorant that appears magenta under white light, and the third layer contains a colorant that appears yellow under white light.The concentration of the colorants in the individual layers of the colorant layers 212 varies spatially, so that a multicolored image is produced when light passes through the image layer 21. In Fig. 2b, the three colorant layers 212 are not shown separately. In the embodiment shown here, the image layer further comprises a protective layer 213, which is a plastic film. The protective layer protects the colorant layers 212 from unintentional damage and thus facilitates handling of the layer system.

[0155] In the embodiment shown here, the colorant layers 212 are arranged between the image carrier layer and the protective layer and were produced using a photochemical process. To produce the colorant layers, three photosensitive layers arranged between the image carrier layer and the protective layer were first exposed and then developed. During development, the colorants were formed, so that in the photochemical process the photosensitive layers were converted into the colorant layers 212. The protective layer was already present before exposure and development. One could therefore say that the colorant layers in this embodiment were produced within the image carrier layer.

[0156] In the exemplary embodiment shown here, the reduction layer 22 comprises only one colorant layer 222. In this embodiment, the colorant layer was created by applying colorant to the reverse side of the image carrier layer 211. To create the colorant layer 222, black ink was printed onto the image carrier layer 211 using a digital printing process. In the embodiment described here, the colorant layer 222 comprises only one type of colorant composition, i.e., only one type of ink. However, the amount of ink applied varies spatially, so that areas where a large amount of black ink was applied appear darker than areas where little black ink was applied. For example, a large amount of black ink was applied to area 29, and little black ink was applied to area 28. The reduction layer 22 could therefore also be described as a monochrome reduction layer.

[0157] In the embodiment of the layer system just described, the image layer 21 was first produced, and then the reduction layer 22 was applied to the image layer 21. The reduction layer 22 and the image layer 21 are therefore bonded together due to the manufacturing process. However, it is also possible for the image layer and the reduction layer of the layer system to be produced separately and then bonded together. Fig. 3 shows a schematic and exemplary cross-section through another embodiment of the layer system. In this embodiment, the layer system 3 comprises an image layer 31 and a reduction layer 32, which were first produced separately and then bonded together over their entire surface, forming an adhesive layer 33. In this embodiment, the reduction layer 32 comprises a reduction layer carrier layer 321 and a colorant layer 322.In this embodiment, the colorant layer 322 was produced by applying colorant to one side of the reduction layer carrier layer 321. To produce the colorant layer 322, several layers with different colorant compositions were printed onto the reduction layer carrier layer 321 using a digital printing process. The colorant layer 322 of the reduction layer 32 therefore appears multicolored, and the reduction layer 32 could also be described as a polychrome reduction layer.For example, four different types of colorant compositions can be used to create such a polychrome reducing layer, wherein a first colorant composition appears cyan under white light, a second colorant composition appears magenta under white light, a third colorant composition appears yellow under white light, and a fourth colorant composition appears black under white light. In this embodiment as well, the amount of applied colorant varies spatially, so that the reducing layer 32 reduces the intensity of the light passing through it to different degrees in different areas and depending on the wavelength of the light.

[0158] In the embodiment described here, the image layer 31 comprises an image layer support layer 311 and a colorant layer 312. In this embodiment, the colorant layer 312 was created by applying colorant to one side of the image layer support layer 311. To create the colorant layer 312, several layers with different colorant compositions were printed onto the image layer support layer 311 using a digital printing process. The colorant layer 312 of the image layer 31 therefore appears multicolored. For example, four different types of colorant compositions can be used to create such an image layer, which appear in the colors cyan, magenta, or yellow, or appear black, under white light.The amount of applied colorant varies spatially, so that the image layer 31 reduces the intensity of the light passing through it to different degrees in different areas and depending on the wavelength of the light.

[0159] Separately produced image and reduction layers can also be joined together in such a way that the colorant layer of the reduction layer is arranged within the layer system. Such an arrangement can be advantageous, for example, if the layer system is to be presented in a display device and the reduction layer is to rest on a diffuser unit. In such a situation, the arrangement of the colorant layer of the reduction layer within the layer system prevents the colorant layer from coming into contact with the diffuser unit and transferring color to it. Fig. 4 shows a schematic and exemplary cross-section through such a layer system. In this embodiment, the layer system 4 comprises an image layer 41 and a reduction layer 42, which were initially produced separately and then joined together over their entire surface by forming an adhesive layer 43.

[0160] In this embodiment, the reducing layer 42 comprises a reducing layer support layer 421 and a colorant layer 422. In this embodiment, the colorant layer 422 was produced by applying colorant to one side of the reducing layer support layer 421. In the embodiment described here, the image layer 41 comprises an image layer support layer 411, a colorant layer 412, and a protective layer 413. In this embodiment, the colorant layer 412 was produced by a photochemical process.

[0161] In the embodiments described with reference to Figures 3 and 4, the colorant layers 322, 422 of the reduction layers 32, 42 were produced by applying colorant to the respective reduction layer support layers 321, 421. However, particularly in embodiments in which the colorant layer of the reduction layer is to be arranged on a reduction layer support layer, the colorant layers of the reduction layer can also be produced using a photochemical process.

[0162] The following describes in more detail an exemplary embodiment of a display device for displaying images using a layer system for displaying images.

[0163] Fig. 5 shows schematically and by way of example a display device 50 for displaying images by means of a layer system, for example one of the embodiments of a layer system described above.

[0164] The display device 50 comprises a fluoroscopy unit 53, a diffuser unit 55 and a holding unit 54. The fluoroscopy unit 53 comprises two active light sources 531, 531', a control unit 56 and a housing 57.

[0165] In this embodiment, the two active light sources 531, 531' can be configured as fluorescent lamps or LED strips. The active light sources 531, 531' produce white light, i.e., light of virtually all wavelengths within the visible range of the electromagnetic spectrum. The transmission unit 53 further comprises a control unit 56, the control unit 56 being configured to control the active light sources 531, 531'. For example, the control unit 56 can be configured to supply current to the active light sources 531, 531'. The control unit 56 can therefore be configured to control whether the active light sources are to be switched on or off. The control unit 56 can also be configured to control the brightness of the active light sources 531, 531'. The control unit 56 can include an input device and / or a communication unit for receiving control commands from a user of the display device 50.The display device 50 further comprises a diffuser unit 55. The diffuser unit 55 is designed to diffuse a large proportion of the light incident on the diffuser unit 55 at its surface and / or within its interior, i.e., in an undirected manner. In this embodiment, the diffuser unit 55 can, for example, be designed as an acrylic glass plate. The light emerging from the diffuser unit 55 exhibits a more uniform spatial intensity distribution than the light originally generated by the active light sources 531, 531' in the region of the diffuser unit 55. In addition, the direction of propagation of the light emerging from the diffuser unit 55 is essentially undirected. The light emerging from the diffuser unit 55 is therefore particularly well suited for illuminating a layer system arranged in front of the diffuser unit 55 in one of the embodiments described above.The transmission unit of the display device 50 further comprises a box-shaped housing 57. The housing 57 is configured to connect the active light sources 531, 531', the diffuser unit 55, and the holding unit 54. The housing 57 comprises five opaque side walls. The sixth side wall is absent, and the housing 57 is closed on this side by the diffuser unit 55. Therefore, the light generated by the active light sources 531, 531' can only exit the housing 57 through the diffuser unit 55. The holding unit 54 is configured to accommodate a layer system for displaying images such that the light provided by the active light sources 531, 531' and the diffuser unit 55 passes through the layer system when the layer system is held by the holding unit 54.The holding unit 54 comprises two clamping strips 541, 541', which exert a clamping effect on the upper and lower regions of the layer system. This clamping effect presses the layer system against the diffuser unit 55 and thus holds it in front of the diffuser unit 55 when the layer system is received by the holding unit. In this exemplary embodiment, the holding unit 54 is therefore designed for the direct attachment of the layer system.

[0166] The display device 50 is configured to accommodate a layer system for displaying images in different orientations. For example, the layer system, comprising an image layer and a reduction layer, can be accommodated by the display device 50 such that the light provided by the display device 50 first strikes the reduction layer, and subsequently the light passing through the reduction layer strikes the image layer. In this case, for example, the reduction layer could lie flat on the diffuser unit. However, the layer system can also be accommodated by the display device 50 such that the light provided by the display device 50 first strikes the image layer, and subsequently the light passing through the image layer strikes the reduction layer. In this case, for example, the image layer could lie flat on the diffuser unit.The orientation that should ultimately be chosen may depend in particular on the details of the embodiment of the layer system. Preferably, the layer system is designed according to one of the embodiments described with reference to Figures 2a, 2b, 3 and 4 and is arranged in the display device 50 such that the light provided by the display device 50 first strikes the reducing layer and subsequently the light passing through the reducing layer strikes the image layer.

[0167] In the embodiment of the display device 50 described here, the layer system is pressed against the diffuser unit 55 by the clamping strips 541, 541' of the holding unit 54 when the layer system is received by the holding unit 54. In alternative embodiments, however, the clamping strips of the holding unit can also be configured to hold the layer system at a certain distance from the diffuser unit. Such a distance can be advantageous if direct contact between the layer system and the diffuser unit is problematic. This can be the case if the layer system could release colorant onto the diffuser unit.

[0168] An embodiment of a method for producing layer systems is described below with reference to a flowchart shown in Fig. 6. Method 600 produces layer systems for displaying images, in particular layer systems for displaying images according to one of the embodiments of a layer system described above.

[0169] In step 601 of procedure 600, image data for an image layer is provided. The image data includes information required for generating the image layer. In particular, the image data defines the image to be generated by the image layer when light passes through it. The image data can, for example, be contained in an image file.

[0170] In step 602 of procedure 600, reduction data for a reduction layer are provided. The reduction data includes information required for generating the reduction layer. In particular, the reduction data defines the image to be produced by the reduction layer when light passes through it. The reduction data can, for example, be contained in an image file.

[0171] In step 603 of method 600, the image layer of the layer system is generated based on the image data. Preferably, the image layer of the layer system is generated by creating colorant layers of the image layer on an image layer support layer. In one embodiment of method 600, the colorant layers of the image layer are printed onto the image layer support layer using a digital printing process. In a preferred embodiment of method 600, which is described in more detail below, the colorant layers of the image layer are created using a photochemical process.

[0172] In step 604 of method 600, the reduction layer of the layer system is generated based on the reduction data. In preferred embodiments of method 600, the reduction layer is generated by creating colorant layers of the reduction layer on the image layer. For example, in one embodiment, the colorant layers of the reduction layer are printed onto the image layer using a digital printing process. In other embodiments of method 600, the reduction layer is generated by creating colorant layers on a reduction layer support layer. The colorant layers can, for example, be applied to the reduction layer support layer using a digital printing process or created on the reduction layer support layer using a photochemical process.

[0173] In particular, if the image layer and the reduction layer are initially produced separately, method 600 can include an optional step 605 in which the produced reduction layer and the produced image layer are joined together. In some embodiments of method 600, the produced reduction layer and the produced image layer are bonded together over a surface area, forming an adhesive layer.

[0174] It should be understood that, although the flowchart in Fig. 6 shows a specific sequence of steps in process 600, the individual steps of process 600 can also be performed in a different order and / or partially in parallel. For example, step 602 can be performed before step 601. It is also possible for step 604 to be performed before step 603.

[0175] Fig. 7 shows a flowchart with details of a preferred embodiment of method 600. In this embodiment, image data for the image layer is provided in step 601. Additionally, high-contrast image data is provided in step 606. The high-contrast image data defines the image to be generated by the layer system when light passes through it. The high-contrast image data can, for example, be contained in an image file.

[0176] In this embodiment, step 602, i.e., the provision of reduction data, comprises sub-steps 6021, 6022, and 6023. In step 6021, the image data and the high-contrast image data are compared. In step 6022, the reduction data is generated based on this comparison. In step 6023, the generated reduction data is provided. Steps 603 and 604 relate to the generation of the image layer and the reduction layer, respectively.

[0177] In the embodiment described here as an example, the high-contrast image data defines an HDR image, and the image data defines an SDR image. The HDR image could, for example, be a photograph taken by an HDR-capable digital camera. The SDR image could, for example, have been generated by reducing the dynamic range of the HDR image. Such a step could also be referred to as dynamic range compression. The SDR image could, for example, also be a photograph from an exposure series taken by a digital camera that is not HDR-capable. In this example, the HDR image could have been calculated from the individual photographs of the exposure series. In general, step 601 can also include generating the image data. Step 606 can also generally include generating the high-contrast image data. In step 6021 of the embodiment described here as an example, the image data and the high-contrast image data are compared.The image data and high-contrast image data are each divided into a pixel grid, with coordinates (x,y) assigned to each pixel. Preferably, the image data contains a brightness value Li(x,y) for each point (x,y), which defines the brightness of the image to be generated by the image layer at that point. Preferably, the high-contrast image data contains a brightness value L2(x,y) for each point (x,y), which defines the brightness of the image to be generated by the layer system at that point. Preferably, comparison factors G(x,y) are calculated according to equation (1) for each point (x,y) based on the brightness values ​​Li(x,y) and L2(x,y), and then normalized and corrected to obtain normalized, corrected comparison factors G'(x,y). If the image data and the high-contrast image data contain color information, the brightnesses Li,i(x,y) and L2,i(x,y) can be compared separately for each color channel i for the comparison in step 6021.Preferably, in this case, comparison factors Gi(x,y) are calculated according to equation (2) for each point (x,y) based on the brightness values ​​Li,i(x,y) and L2,i(x,y), and then normalized and corrected to obtain normalized, corrected comparison factors Gi'(x,y). A comparison of the brightnesses for each of several color channels can be performed, in particular, if the image data and the high-contrast image data are encoded in the same color system and / or color space.

[0178] Based on these normalized, corrected comparison factors G'(x,y) or Gi'(x,y), the reduction data are generated in step 6022. For example, the normalized, corrected comparison factors G'(x,y) or Gi'(x,y) can be combined to form a comparison factor image from which the reduction data are generated. Preferably, the reduction data correspond to the comparison factor image. Based on these reduction data, the reduction layer can be produced in a later step of process 600 using a digital printing process and / or a photochemical process.

[0179] Although in the embodiment of the method described with reference to Fig. 7 the image data and the high-contrast image data are first provided, and the reduction data is generated based on a comparison of the image data and the high-contrast image data, in other embodiments of the method 600 such a comparison can already be carried out during the creation of the image information. In one exemplary embodiment, the image data and the high-contrast image data are encoded in a common image file, wherein this image file does not directly store both the image data and the high-contrast image data, but only the high-contrast image data and additionally a conversion information. Based on the stored conversion information and the high-contrast image data, however, the image data can be calculated. In this example, the conversion information comprises a comparison factor image formed from comparison factors.The reduction data are therefore generated based on the conversion information and are designed in such a way that the reduction layer generated on this basis essentially produces the comparison factor image of the conversion information when light passes through it.

[0180] In another example, the high-contrast image data defines an HDR image captured with an HDR-capable recording device. This device has already calculated and stored the SDR image data, the HDR image data, and the conversion information in a single file. In this example, the conversion information is a so-called "gain map," which is automatically generated by many HDR-capable recording devices, especially HDR-capable smartphones or digital cameras, when capturing HDR images. Such a gain map is typically defined for each area of ​​an image and allows the conversion of SDR image data to HDR image data and vice versa. For example, the gain map can be defined for each pixel of an image. The gain map defined for each pixel could also be summarized as a comparison factor image. The gain map can also be stored in a compressed form, for example, to reduce storage requirements.In this case, the compressed gain map can be processed using common resampling techniques to obtain an uncompressed gain map defined in each pixel of an image. This uncompressed gain map, defined in each pixel, could also be aggregated as a comparison factor image. Specifically, when the gain map can be aggregated as a comparison factor image, the reduction data can be generated based on the provided conversion information, i.e., the provided gain map. For example, the comparison factor image generated from the gain map could be used directly as reduction data. The reduction data could also be proportional to the gain map, allowing the structure of this gain map to be printed onto the image layer or a reduction layer support layer to create the reduction layer.

[0181] As described above, in step 603 of a preferred embodiment of the method 600, the colorant layers of the image layer are produced using a photochemical process. In this embodiment, an image layer support layer is first provided, onto which several photosensitive layers are applied. Optionally, further layers, such as one or more release layers, one or more adhesive layers, a protective layer, or an antihalation layer, can be applied to the image layer support layer and / or the photosensitive layers. Fig. 8a schematically shows an exemplary embodiment of a provided image layer support layer 810, onto which further layers for the production of colorant layers of the image layer are applied using a photochemical process. The image layer support layer 810 is preferably a polyethylene plastic film.The further layers comprise an adhesive layer 820, a first photosensitive layer 830, a first separating layer 840, a second photosensitive layer 850, a second separating layer 860, a third photosensitive layer 870, a protective layer 880, and an antihalation layer 890. The first photosensitive layer 830 contains silver halide crystals 831, schematically represented as triangles, and a colorless yellow color coupler 832, schematically represented as open circles. The second photosensitive layer 850 contains silver halide crystals 851, schematically represented as triangles, and a colorless magenta color coupler 852, schematically represented as open circles. The third photosensitive layer 870 contains silver halide crystals 871, schematically represented as triangles, and a colorless cyan color coupler 872, schematically represented as open circles.The photosensitive layers 830, 850, and 870 also contain components that increase or decrease their sensitivity to light of specific wavelengths. Layers 810, 820, 830, 840, 850, 860, 870, 880, and 890 could also be described as precursor layers 800 for the image layer.

[0182] To form the spatially inhomogeneous colorant layers of the image layer, the precursor layer 800 is exposed to light of different wavelengths in a subsequent step. Preferably, a laser exposure unit is used, which exposes the precursor layer 800 with laser light of different wavelengths. When light strikes the photosensitive layers 830, 850, and 870, the silver ions are partially reduced to silver and form silver clusters. The efficiency of the conversion of silver ions to silver upon light exposure is wavelength-dependent and occurs in the first photosensitive layer 830 primarily when light of a first wavelength strikes it.In the second photosensitive layer 850, the conversion of silver ions to silver occurs primarily when light of a second wavelength strikes the layer, while in the third photosensitive layer 870, the conversion occurs primarily when light of a third wavelength strikes the layer. Depending on the respective intensities of light of the first, second, or third wavelength, a different number of silver clusters are formed. The spatial distribution of the silver clusters in this example could be described as a latent image.

[0183] In a further step, the exposed, photosensitive layers 830, 850, and 870 are developed. During development, the precursor layer 800 is exposed to chemicals that could also be called developers. In the area of ​​the silver clusters, the developers react with the color couplers 832, 852, and 872, and with a portion of the silver contained in the photosensitive layers, to form dyes. Furthermore, during development, the remaining silver halide crystals 831, 851, and 871 are removed, so that the layers, which were photosensitive before development, are no longer photosensitive after development. During development, the previously strongly light-absorbing antihalation layer 890 also becomes transparent.

[0184] Fig. 8b schematically shows the layer sequence after development, which was designated as precursor layer 800 before development. After development, the layer sequence could also be designated as image layer 800'. In addition to the image layer support layer 810, the adhesion layer 820, the release layers 840 and 860, the protective layer 880, and the now transparent antihalation layer 890', the image layer 800' now also includes the colorant layer 830', which contains a dye 833 formed during development that appears yellow under white light; the colorant layer 850', which contains a dye 853 formed during development that appears magenta under white light; and the colorant layer 870', which contains a dye 873 formed during development that appears cyan under white light.

[0185] In the following, another exemplary embodiment of a display device for displaying images using a layer system is presented with reference to Figures 9, 10 and 11.

[0186] Fig. 9 schematically and by way of example shows a display device 950 for displaying images using a layer system, for example, a layer system according to one of the embodiments described above. The display device 950 comprises an anti-reflective glass plate 915, a diffuser unit 955 arranged below the glass plate in the form of an acrylic glass sheet, and a holding unit 954, which here is designed as a surrounding frame, for example, in the form of an aluminum profile. The diffuser unit 955 is designed to diffuse a large proportion of the light incident on the diffuser unit 955 diffusely, i.e., in an undirected manner, on its surface and / or within its interior. In addition, the direction of propagation of the light emerging from the diffuser unit 955 is essentially undirected. In Fig. 9, no layer system is inserted into the display device 950.A layer system for displaying images would be arranged between the diffuser unit 955 and the anti-reflective glass plate 915 when using the display device 950. In Fig. 9, further elements of the display device 950 are concealed by the diffuser unit 955 and the holding unit 954. Fig. 10 shows a schematic and exemplary representation of the display device 950 after the holding unit 954, the glass plate 915, and the diffuser unit 955 have been removed. The diffuser unit 950 comprises a housing 957, which here is designed as a sheet steel tray. The housing 957 comprises several supports 9571, 9571', 9571" and 9571 on which the diffuser unit 955 rests when the display device 950 is assembled as shown in Fig. 9. The display device 950 further comprises a fluoroscopy unit 953.In this embodiment, the transmission unit 953 comprises a plurality of active light sources 9531, which are configured here as white LEDs. The light sources 9531 are arranged in a matrix, for example, in a matrix of 24x36 light sources 9531. During operation, the light sources 9531 form a matrix of corresponding light points. The transmission unit 953 further comprises a control unit 956, wherein the control unit 956 is configured to control the active light sources 9531. For example, the control unit 956 can be configured to supply current to the active light sources 9531. The control unit 956 can therefore be configured to control whether the active light sources are to be switched on or off. The control unit 956 can further be configured to control the brightness of the active light sources 9531.The control unit 956 can include an input device and / or a communication unit for receiving control commands from a user of the display device 950. In this embodiment, the control unit 956 can further be configured to automatically control the brightness of the active light sources 9531 depending on the brightness of the ambient light. For this purpose, the control unit 956 can, for example, include a dimmer unit. Fig. 11 shows a schematic and exemplary section through the display device 950, in which the holding unit 954 is mounted on the housing 957 and a layer system 960 for displaying high-contrast images is inserted into the display device. The layer system 960 is arranged between the diffuser unit 955 and the anti-reflective glass plate 915. The holding unit 954 holds the anti-reflective glass plate 915, and thus also the layer system 960 and the diffuser unit 955, in the display device 950.The holding unit 954 described here as an example is therefore designed for the indirect fastening of the layer system. In order to detachably connect the holding unit 954 and the housing 957, the holding unit 954 comprises several magnetic strips 910, 910', 910",", 910'", wherein the housing 957 and the magnetic strips 910, 910', 910",", 910'" are designed such that they attract each other. The magnetic strips 910, 910', 910", 910'" are further arranged on foam strips 911, 911', 911", 911 to enable the most form-fitting possible interlocking of the holding unit 954 and the housing 957, without the holding unit 954 tilting when it is detached from the housing 957. The X-ray unit 953 with a plurality of active light sources 9531 is also shown in Fig. 11.The distance between the active light sources 9531 and the diffuser unit 955 is selected such that the light emerging from the diffuser unit 955 has a uniform spatial intensity distribution and is therefore particularly well suited for illuminating the layer system 960 arranged in front of the diffuser unit 955. The housing 957 also includes hangers 922 with which the display device 950 can be suspended in suitable wall brackets, for example, wall hooks. Felt discs 921 prevent the display device 950 from damaging the wall. For the embodiment of the display device 950 described here, exemplary dimensions are given below with reference to Fig. 11. It should be understood that Fig. 11 is not a scale drawing. It should also be understood that the basic shape of the display device 950 is a rectangle and the one shown in Fig.The section shown in Figure 11 runs parallel to the longer side of the rectangle. Length measurements relating to the dimension parallel to the longer side of the rectangle are also referred to as height in the following. In the embodiment shown here, the glass dimension 901, i.e., the height of the glass plate 915, is, for example, 500.00 mm and corresponds essentially to the height of the layer system 960 and the diffuser unit 955. The internal dimension 906 of the housing 957 is 500.50 mm and is therefore slightly larger than the glass dimension 901, which makes inserting the diffuser unit 955, the layer system 960, and the glass plate 915 into the housing 957 particularly easy. In this example, the outer dimension 905 of the housing 957 is 502.50 mm, the depth 918 of the housing 957 is 47.5 mm, the projection 916 is 3.50 mm, and the thickness 919 of the steel sheet of the housing 957 is 0.80 mm. The felt disc 921 can, for example, have a diameter of 18 mm and a thickness of 4.5 mm.In the embodiment shown here, the distance 923 between the active light sources 9531 of the transmission unit 953 and the diffuser unit 955 is approximately 35 mm, with the thickness 924 of the diffuser unit 955 being 3 mm. The thickness 925 of the coating system 960 is less than 1 mm in this embodiment, and the thickness 926 of the anti-reflective glass plate 926 is 3 mm. In the embodiment described here, the holding unit 954 can have the following dimensions: an outer dimension 902 of 515.50 mm, a profile height 908 of 14.15 mm, a total profile depth 909 of 52.50 mm, a partial profile depth 9092 of 4.5 mm, a profile clearance 9093 of 2.35 mm, and an allowance 912 of 6.50 mm. The magnetic tapes 910, 910', 910", 910'" can have a thickness of 1.00 mm and the corresponding foam tapes 911, 911', 911", 91T" can have a thickness of 3.00 mm. With these dimensions, a profile projection 9071 of approximately 1.00 mm and a distance 9072 to the wall of approximately 3.50 mm result.The overall depth 907 of the display device with the felt disc 921 is approximately 55.80 mm in this embodiment. Furthermore, these dimensions result in an overlap 904 of 6.40 mm and thus a visible dimension 903 of 487.20 mm. As mentioned above, the basic shape of the display device 950 in the embodiment described here is a rectangle, with the short side and the long side of the rectangle having an aspect ratio of approximately 2:3. Length measurements that refer to the dimension parallel to the shorter side of the rectangle could also be called widths. In the embodiment shown here, the width of the anti-reflective glass plate 915 is approximately 2 / 3 of the glass dimension 901. The respective widths of the other elements are adjusted accordingly. In further embodiments of the display device 950, the height and width of the display device may deviate from the values ​​given here as examples.However, some of the dimensions in these further embodiments may also correspond to the dimensions mentioned above as examples. This may be the case in particular for some or all of the following dimensions: the thicknesses of the diffuser unit, the layer system, and the anti-reflective glass plate; the thicknesses of the magnetic strips, the foam strips, and the sheet steel of the housing; the dimensions of the felt discs; but also the profile height, the total profile depth, the partial profile depth, the profile clearance depth, and the allowance, as well as the overlap, the profile overhang, and the distance to the wall. Fig. 12a shows schematically and by way of example another embodiment of a display device for displaying images by means of a layer system with a corresponding layer system for displaying images.In this exemplary embodiment, the display device 1201 comprises a light-emitting frame 1254, which combines the functions of a transmission unit and a holding unit. The display device 1201 further comprises a diffuser unit 1255, which is covered by the layer system 1202 in Fig. 12a. The display device 1201 is configured to provide the light passing through the layer system 1202 to generate the image by means of edge illumination of the diffuser unit 1255, as will be explained below.

[0187] Fig. 12b shows a schematic and exemplary sectional view of the display device 1201 along the dashed line 1210 in Fig. 12a. The light frame 1254 accommodates the edge areas of the diffuser unit 1255 and the layer system 1202. Furthermore, the display device 1201 includes hangers 1230 with which the display device 1201 can be suspended in suitable wall brackets, for example, wall hooks.

[0188] Fig. 12c schematically and by way of example shows an enlarged section of the sectional view shown in Fig. 12b. The light frame 1254 comprises two partial profiles 1254a and 1254b, which can be detachably connected to one another. Furthermore, the light frame 1254 comprises foam strips 1254c, 1254d, which are designed such that the diffuser unit 1255 and the layer system 1202 are securely held between the two partial profiles 1254a, 1254b when the diffuser unit 1255 and the layer system 1202 are inserted into the light frame 1254 and the two partial profiles 1254a, 1254b are connected to one another. The light frame 1254 may also include fasteners designed to detachably connect the two partial profiles 1254a, 1254b to one another. Examples of suitable fasteners include screws, clamps, or magnetic elements. The two partial profiles 1254a and 1254b are specifically designed to fasten the diffuser unit 1255.Preferably, in the embodiment shown here, the layer system 1202 is connected to the diffuser unit 1255, wherein the diffuser unit 1255 is mechanically more stable than the layer system 1202. In this example, the layer system 1202 is therefore primarily secured in the display device 1201 by the fact that the diffuser unit 1255 is attached to the display device 1201. In this case, the holding unit is designed in the form of the partial profiles 1254a, 1254b to accommodate and indirectly secure the layer system.

[0189] The light frame 1254 further comprises a backlighting unit 1252, which includes an active light source in the form of a circumferential LED strip 1253. The LED strip 1253 is designed and arranged such that the light generated by the LED strip 1253 predominantly strikes the edge 1255a of the diffuser unit 1255. In the embodiment described here, the diffuser unit 1255 is designed to diffuse the light entering via the edge 1255a predominantly within the diffuser unit 1255, so that a portion of the light generated by the LED strip 1253 passes through the layer system 1202. The diffuser unit 1255 can, for example, be made of partially transparent acrylic glass.

[0190] The layer system 1202 comprises a reducing layer 1221 and an image layer 1222, wherein, as shown in Fig. 12c, the reducing layer 1221 preferably faces the diffuser unit 1255. However, it is also conceivable that the image layer 1222 faces the diffuser unit 1255, so that the light exiting the diffuser unit 1255 in the direction of the layer system 1202 first passes through the image layer 1222 and then through the reducing layer 1221. In the embodiment shown here, the layer system 1202 is preferably connected to the diffuser unit 1255. For example, the layer system 1202 can be bonded to the diffuser unit 1255 over its entire surface or in partial areas. However, it is also conceivable that the layer system 1202 is produced directly on the diffuser unit 1255. For example, the reduction layer and / or the image layer can be created by directly applying colorant to the diffuser unit 1255.It is also conceivable that only one of the layers of the layer system 1202 is produced directly on the diffuser unit. For example, the reduction layer 1221 can be produced by directly printing colorant layers onto the diffuser unit 1255. An image layer 1202, initially produced separately and comprising an image layer support layer and one or more colorant layers, can then be combined with the diffuser unit 1255 and the reduction layer 1201. In the embodiment shown here, the edge illumination of the diffuser unit 1255 can cause the intensity of the light emitted from the diffuser unit 1255 to vary spatially. In particular, the intensity of the light emitted from the diffuser unit 1255 can decrease with increasing distance from the illuminated edge 1255a.The reducing layer 1221 is therefore preferably configured to partially or completely compensate for the spatial variation in the intensity of the light emerging from the diffuser unit 1255. In particular, the reducing layer 1221 can be configured to reduce the intensity of the light passing through it less sharply with increasing distance from the illuminated edge 1255a. A reducing layer 1221 configured in this way can ensure that the displayed image has a spatially uniform brightness.

[0191] Further examples of layer systems are described below with reference to Figures 13 and 14.

[0192] Fig. 13 schematically and exemplarily shows a section through another embodiment of the layer system. In this embodiment, the layer system 13 comprises an image layer 131 and a reduction layer 132. The layer system 13 is designed such that when light passes through the image layer 131 and the reduction layer 132, an HDR image, i.e., an image with a particularly high dynamic range, can be generated.

[0193] In the embodiment described here, the image layer 131 comprises an image layer support layer 1311 and colorant layers 1312. The image layer support layer 1311 can, in particular, be a sheet made of polymethyl methacrylate, also known as acrylic glass. In this embodiment, the colorant layers 1312 were produced by applying colorant to one side of the image layer support layer 1311. To produce the colorant layers 1312, several layers with different colorant compositions were printed onto the image layer support layer 1311 using a digital printing process. The colorant layers 1312 of the image layer 131 therefore appear multicolored. For example, four different types of colorant compositions can be used to produce such an image layer, which appear in the colors cyan, magenta, or yellow, or appear black, under white light.The amount of applied colorant varies spatially, so that the image layer 131 reduces the intensity of the light passing through it to different degrees in different areas and depending on the wavelength of the light. In this embodiment, the colorant layers 1312 of the image layer 131 are designed such that when light passes through the image layer, a corresponding SDR image, i.e., an image with a smaller dynamic range than the HDR image, is generated.

[0194] Furthermore, in this embodiment, the reduction layer 132 comprises colorant layers 1322. In this embodiment, the colorant layers 1322 were created by applying colorant directly to the colorant layers 1312 of the image layer. To create the colorant layers 1322, one or more layers of the same colorant composition were printed onto the reduction layer carrier layer 1321 using a digital printing process. The colorant layers 1322 of the reduction layer 132 therefore appear monochromatic, and the reduction layer 132 could also be referred to as a monochrome reduction layer. In a modified embodiment, however, the colorant layers can also comprise several colorant compositions, so that the corresponding reduction layer could be referred to as a polychromatic reduction layer.In this embodiment, the reduction layer 132 is preferably based on a comparison factor image generated by comparing SDR image data and HDR high-contrast image data. In particular, the reduction layer 132 can be configured such that when light passes through it, an image corresponding to the comparison factor image is generated. In this example, the comparison factor image can, in particular, correspond to or be based on a gain map. Therefore, in this case, one could also say that the reduction layer 132 corresponds to or is based on the gain map, or that the gain map is printed onto the image layer 131 to generate the reduction layer 132.

[0195] The image layer 131 can be designed to generate the SDR image in particularly high quality. High quality can be achieved, in particular, by using high spatial resolution, particularly fine color gradations, and high color fidelity. The reduction layer 132 can be designed to generate a particularly large dynamic range when light passes through it. A particularly large dynamic range can be achieved, in particular, by using highly absorbing and / or highly scattering colorants. Alternatively or additionally, in those areas of the reduction layer 132 that are intended to appear very dark when light passes through, the colorants of the reduction layer can be applied in multiple layers.By combining the image layer 131 and the reduction layer 132, an HDR image with a particularly high dynamic range and exceptionally high quality can be generated. Fig. 14 schematically and exemplarily shows a cross-section through another embodiment of the layer system. In this embodiment, the layer system 14 comprises an image layer 141 and a reduction layer 142. The layer system 14 is designed such that when light passes through the image layer 141 and the reduction layer 142, an HDR image, i.e., an image with a particularly high dynamic range, can be generated.

[0196] In the embodiment described here, the image layer 141 comprises an image layer support layer 1411 and colorant layers 1412. As in the previously described embodiment, the image layer support layer 1411 can, in particular, be a sheet made of polymethyl methacrylate. In this embodiment, the colorant layers 1412 were produced by applying colorant to the front surface of the image layer support layer 1411. Furthermore, in this embodiment, the reduction layer 142 comprises colorant layers 1422. In this embodiment, the colorant layers 1422 were produced by applying colorant to the back surface of the image layer support layer 1411. The reduction layer 142 can be configured as a polychromatic reduction layer or as a monochrome reduction layer.

[0197] The color medium layers 1412 of the image layer 141 are designed such that when light passes through the image layer, an SDR image with a smaller dynamic range than the HDR image is generated. As in the embodiment described with reference to Fig. 13, the reduction layer 142 is preferably based on a comparison factor image, more preferably on a gain map.

[0198] In the embodiments shown by way of example in Figures 13 and 14, the colorant layers of the respective image layer were produced first, followed by the colorant layers of the respective reduction layer. However, in variations of these embodiments, the colorant layers of the reduction layer can also be produced first. In this case, the layer onto which colorant is applied—such as a polymethyl methacrylate plate—could also be referred to as the reduction layer support layer. Thus, the reduction layer could be produced first, and then the image layer created by applying colorant to the reduction layer. Similar to the embodiment shown in Fig.In the embodiment shown in Fig. 13, for example, the colorant layers of the reduction layer can first be printed onto a polymethyl methacrylate plate, and then the colorant layers of the image layer can be printed onto the colorant layers of the reduction layer. Similarly, as in the embodiment shown in Fig. 14, the colorant layers of the reduction layer can first be printed onto the front side of a polymethyl methacrylate plate, and then the colorant layers of the image layer can be printed onto the back side of the plate. In the claims, the words "have" and "comprise" do not exclude other elements or steps, and the indefinite article "a" does not exclude a plurality.

[0199] A single unit or device can perform the functions of several elements listed in the claims. The fact that individual functions and elements are listed in different dependent claims does not preclude the possibility of advantageously using a combination of these functions or elements.

[0200] The display device described above includes, in preferred embodiments, an active light source. Particularly when the active light source is electrically operated, the display device may also include a control unit, for example, for the active light source. In one example, the control unit is a mechanical switch. However, the control unit of the display device may also include a computer unit, which may, for example, comprise a processor, a memory unit, a control unit for switching functions of the display device on and off in a controlled manner, and / or a communication unit for connecting the computer unit to other computers, networks, and / or remote controls.

[0201] The control, for example of the active light source of the display device, can be implemented as program code of a computer program or several computer programs and / or as corresponding hardware.

[0202] A computer program, or parts of a computer program such as the aforementioned control system, can be stored and / or distributed on a suitable medium, such as an optical storage medium or a solid-state storage medium, which is sold together with or as part of other hardware. However, the computer program can also be distributed in other forms, for example via the internet or other telecommunications systems.

[0203] The reference numerals in the claims are not to be understood as limiting the subject matter and scope of protection of the claims by these reference numerals.

Claims

- 68 - Claims 1. A layer system for displaying images, in particular for displaying high-contrast images, wherein the layer system (2; 3; 4) is configured such that an image is generated when light (5, 5') passes through the layer system (2; 3; 4), wherein the layer system (2; 3; 4) comprises: an image layer (21 ; 31 ; 41; 800'), wherein the image layer (21 ; 31 ; 41 ; 800') is designed such that when light (5, 5') passes through the image layer (21 ; 31 ; 41 ; 800') the image is generated with a first intensity distribution, a reducing layer (22; 32; 42), wherein the reducing layer (22; 32; 42) is configured to reduce the intensity of light (5, 5') passing through the reducing layer (22; 32; 42) such that when light (5, 5') passes through the reducing layer (22; 32; 42) and the image layer (21; 31; 41; 800') the image is produced with a second intensity distribution, where the difference between the greatest intensity of the first intensity distribution and the smallest intensity of the first intensity distribution is smaller than the difference between the greatest intensity of the second intensity distribution and the smallest intensity of the second intensity distribution.

2. Layer system according to claim 1, characterized in that the image layer (21 ; 31 ; 41 ; 800') comprises an image layer support layer (211 ; 311 ; 411 ; 810).

3. Layer system according to claim 2, characterized in that the image layer support layer comprises a plate made of polymethyl methacrylate.

4. Layer system according to one of the preceding claims, characterized in that the image layer (21 ; 31 ; 41 ; 800') comprises one or more colorant layers (212; 312; 412; 830', 850', 870') and / or that the reduction layer (22; 32; 42) comprises one or more colorant layers (222; 322; 422).

5. Layer system according to claim 4, characterized in that the one or more colorant layers (222) of the reduction layer (22) were produced by applying colorant to the image layer (21).- 69 - 6. Layer system according to claim 4, characterized in that the reducing layer (32; 42) has a reducing layer carrier layer (321; 421), wherein the one or more colorant layers (322; 422) of the reducing layer (32; 42) were produced by applying colorant to the reducing layer carrier layer (321; 421).

7. Layer system according to one of claims 4 to 6, characterized in that the colorant layers (222; 422) of the reduction layer (22; 42) comprise only one type of colorant composition or several types of colorant compositions.

8. Layer system according to one of the preceding claims, wherein the layer system is configured to display an HDR image, wherein the image layer is configured such that when light passes through the image layer and not through the reduction layer, the image is generated as an SDR image, and wherein the reduction layer is configured such that when light passes through the image layer and the reduction layer, the image is generated as an HDR image.

9. Display device for displaying images using a layer system (2; 960; 1202) according to one of claims 1 to 8, wherein the display device (1; 50; 950; 1201) comprises: a fluoroscopy unit (3; 53; 953; 1252) designed to provide light (5) and a holding unit (4; 54; 954; 1254) designed to accommodate the shift system (2; 960; 1202), wherein the transmission unit (3; 53; 953; 1252) and the holding unit (4; 54; 954; 1254) are designed and arranged such that the provided light (5) passes through the reducing layer (22; 1221) and the imaging layer (21; 1222) of the layer system (2; 960; 1202) when the layer system (2; 960; 1202) is held by the holding unit (4; 54; 954; 1254).

10. Display device according to claim 9, characterized in that the X-ray unit (3; 53; 953; 1252) comprises an active light source (3; 531 , 531 '; 9531 ; 1253).

11. Display device according to one of claims 9 and 10, characterized in that the display device (1; 50; 950; 1201) comprises a diffuser unit (6; 55; 955; 1255), wherein the diffuser unit (6; 55; 955; 1255) is arranged between the fluoroscopy unit (3; 53; 953; 1252) and the layer system (2; 960; 1202) when the- 70 - The layer system (2; 960; 1202) is received by the holding unit (4; 54; 954; 1254) and the diffuser unit (6; 55; 955; 1255) is configured to scatter the provided light (5).

12. Display device according to one of claims 9 to 11, characterized in that the transmission unit (3; 53; 953; 1252) and the holding unit (4; 54; 954; 1254) are designed and arranged such that the provided light (5) first passes through the reduction layer (22; 1221) and then through the image layer (21; 1222) of the layer system (2; 960; 1202) when the layer system (2; 960; 1202) is received by the holding unit (4; 54; 954; 1254).

13. Method for producing a layer system (2; 3; 4; 960; 1202) for displaying images according to any one of claims 1 to 8, wherein the method (600) comprises the following steps: Providing image data (601) for the image layer, Providing reduction data (602) for the reduction layer, Generating the image layer (603) based on the provided image data, and generating the reduction layer (604) based on the provided reduction data.

14. The method of claim 13, characterized in that the method (600) comprises: Providing high-contrast image data (606) for the layer system (2; 3; 4, 960; 1202), where providing reduction data (602) for the reduction layer includes: Generating reduction data (6022) based on a comparison (6021) of the provided image data and the provided high-contrast image data.

15. Method according to one of claims 13 and 14, characterized in that the image layer comprises an image layer support layer and one or more colorant layers, wherein generating the image layer (603) based on the provided image data comprises: - 71 - Providing the image layer support, wherein one or more photosensitive layers are applied to the provided image layer support, exposing the photosensitive layers and Developing the exposed, light-sensitive layers.

16. Method according to any one of claims 13 to 15, characterized in that the reduction layer comprises a reduction layer carrier layer and one or more colorant layers, wherein generating the reduction layer (604) based on the provided reduction data comprises: Providing the reduction layer carrier layer and Application of colorant to the reduction layer carrier layer.

17. Method according to any one of claims 13 to 15, characterized in that the reduction layer comprises one or more colorant layers, wherein generating the reduction layer (604) based on the provided reduction data comprises: Application of colorant to the image layer to create the colorant layers of the reduction layer.

18. Reducing layer for use with an image layer, wherein the image layer (21; 31; 41; 800') is configured such that when light passes through the image layer (21; 31; 41; 800') an image with a first intensity distribution is produced, wherein the reducing layer (22; 32; 42) is partially transparent to light, wherein the reducing layer (22; 32; 42) is configured to reduce the intensity of light (5) passing through the reducing layer (22; 32; 42) such that when light (5) passes through the reducing layer (22; 32; 42) and the image layer (21; 31; 41; 800') the image with a second intensity distribution is produced, wherein the difference between the highest intensity of the first intensity distribution and the lowest intensity of the first intensity distribution is smaller is defined as the difference between the highest intensity of the second intensity distribution and the lowest intensity of the second intensity distribution.

Images