EP4689942A1 - Masking element - Google Patents

Abstract

A display device (100) is disclosed, comprising: - at least one pattern illumination source (112) configured for emitting an infrared light pattern (116), - at least one flood illumination source (114) configured for emitting infrared flood light (118), - at least one image generation unit (150) configured for generating at least one pattern image while the pattern illumination source (112) is emitting the infrared light pattern (116) and configured for generating at least one flood image while the flood illumination source (114) is emitting infrared flood light (118), - at least one masking element (130) configured for covering at least one contiguous area around the flood illumination source (114) and/or the pattern illumination source (112), - at least one display (140) configured for displaying content, wherein the display (140) covers at least partially the pattern illumination source (112), the flood illumination source (114), the masking element (130) and/or the image generation unit (150).

Description

Masking element

Description

Field of the invention

The invention relates to a display device and a method for authenticating a user of a device. The present invention further relates to a computer program, a computer-readable storage medium and a non-transient computer-readable medium.

The devices, methods and uses according to the present invention specifically may be employed for example in various areas of daily life, security technology, gaming, traffic technology, production technology, photography such as digital photography or video photography for arts, documentation or technical purposes, safety technology, information technology, agriculture, crop protection, maintenance, cosmetics, medical technology or in the sciences. However, other applications are also possible.

WO 2023/025726 A1 discloses a method for determining a depth map of at least one. The method comprises the following steps: a) illuminating a scene comprising the object by using at least one flood light source, wherein the illumination from the flood light source has a predefined and/or predetermined light direction, imaging at least one pixelated flood image of the scene by using at least one camera; b) projecting at least one illumination pattern on the scene y using at least one projector and imaging at least one pixelated reflection image using the camera, wherein the reflection image comprises a plurality of reflection features generated by the scene in response to the illumination pattern, wherein each of the reflection features comprises a beam profile; c) evaluating the flood image by using at least one evaluation device thereby determining reflectance R(x) for each pixel position x of the flood image; d) evaluating the reflection image by using the evaluation device, wherein the evaluation comprises, for each reflection feature, determining depth information by analysis of its respective beam profile and determining at least one physical light property A(x) for the respective pixel position x of the reflection image; e) the evaluation device, assigning, for each reflection feature, the determined depth information and the determined physical light property A(x) to a corresponding pixel of the flood image and extrapolating the determined depth information and the determined physical light property A(x) to similar pixels of the flood image around said corresponding pixel; f) the evaluation device, determining the depth map by using a shape-from- shading technique considering the determined reflectance R(x), the determined depth information and the determined physical light property A(x).

US 2020/0082155 A1 discloses a facial recognition authentication process utilizing images of a user's face that are captured while the user is being illuminated using both flood infrared illumination and patterned illumination (e.g., speckle pattern illumination). As the user's face is illuminated by both flood infrared illumination and patterned illumination, the captured images may include both flood infrared illumination data and depth map image data. Flood infrared illumination data may be generated from the images to assess two-dimensional features of the user in the captured images. Depth map image data may be generated from the pattern data in the images to assess three-dimensional (depth) features of the user in the captured images. The flood infrared illumination data and the depth map image data may be used separately by facial recognition authentication process to attempt to authenticate the user in the captured images as an authorized user of the device.

Prior art

Available authentication systems in mobile devices such as in smartphones, tablets and the like, include cameras. Said mobile devices usually have a front display such as an organic lightemitting diode (OLED) area and/or a quantum-dot light emitting diode (QLED) area.

A typical light emitter, such as a light source like a light emitting diode and/or a laser, and a receiver, such as a camera and/or further light sensor, may be positioned behind a display. The emitter may, typically, emit light through the display and the receiver receives light through the display. In case the emitter, emits light at the same time the receiver measures the received light, cross talk may occur. That the emitter and the receiver are synchronized may usually be required, as the receiver may have to receive light generated by the emitter that got reflected from the scene in front of the display. The problem is that not all light travels the intended light path. This may result in unwanted light measured with the receiver that is not related to the signal, which may be associated with reflected light from the scene in front of the display. This effect is, typically, referred to as crosstalk and/or stray light. These effects may distort and/or changes the measured signal. In case a camera is used, the cross talk may even be visible in the image. Thereby, crosstalk may negatively influence the system performance, since signal- and/or image-processing steps for deriving a measurement result may not correctly function on the image may anymore. Further, the emitted light may influence the TFTs and, thereby, trigger light emission in the emission layer. This may even cause flickering effects being unpleasant and distracting for the user.

Problem addressed by the invention

It is therefore an object of the present invention to provide devices and methods facing the above-mentioned technical challenges of known devices and methods. Specifically, it is an object of the present invention to provide devices and methods, which allow preventing crosstalk and flickering effects, particularly for improving the repeatability and/or accuracy of an authentication process of a user.

Summary of the invention

This problem is solved by the invention with the features of the independent patent claims.

Advantageous developments of the invention, which can be realized individually or in combination, are presented in the dependent claims and/or in the following specification and detailed embodiments.

In a first aspect of the present invention, a display device is disclosed. The display device comprises: at least one pattern illumination source configured for emitting an infrared light pattern, at least one flood illumination source configured for emitting infrared flood light, at least one image generation unit configured for generating at least one pattern image while the pattern illumination source is emitting the infrared light pattern and configured for generating at least one flood image while the flood illumination source is emitting infrared flood light, at least one masking element configured for covering at least one contiguous area around the flood illumination source and/or the pattern illumination source, at least one display configured for displaying content, wherein the display covers at least partially the pattern illumination source, the flood illumination source, the masking element and/or the image generation unit.

The term “light” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to electromagnetic radiation in one or more of the infrared, the visible and the ultraviolet spectral range. Herein, the term “ultraviolet spectral range”, generally, refers to electromagnetic radiation having a wavelength of 1 nm to 380 nm, preferably of 100 nm to 380 nm. Further, in partial accordance with standard ISO- 21348 in a valid version at the date of this document, the term “visible spectral range”, generally, refers to a spectral range of 380 nm to 760 nm. The term “infrared spectral range” (IR) generally refers to electromagnetic radiation of 760 nm to 1000 pm, wherein the range of 760 nm to 1.5 pm is usually denominated as “near infrared spectral range” (NIR) while the range from 1 .5 p to 15 pm is denoted as “mid infrared spectral range” (MidlR) and the range from 15 pm to 1000 pm as “far infrared spectral range” (FIR). Preferably, light used for the typical purposes of the present invention is light in the infrared (IR) spectral range, more preferred, in the near infrared (NIR) and/or the mid infrared spectral range (MidlR), especially the light having a wavelength of 1 pm to 5 pm, preferably of 1 pm to 3 pm.

The term “illuminate”, as used herein, is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to the process of exposing at least one element to light. The term “illumination source” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary device configured for generating or providing light in the sense of the above-mentioned definition. The term “pattern illumination source” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary device configured for generating or providing at least one light pattern, in particular at least one infrared light pattern. The term “light pattern” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one arbitrary pattern comprising a plurality of light spots. The light spot may be at least partially spatially extended. At least one spot or any spot may have an arbitrary shape. In some cases a circular shape of at least one spot or any spot may be preferred. The spots may be arranged by considering a structure of a display comprised by a device that is further comprising the display device. Typically, an arrangement of an OLED-pixel-structure of the display may be considered. The term “infrared light pattern” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a light pattern comprising spots in the infrared spectral range. The infrared light pattern may be a near infrared light pattern.

The infrared light may be coherent. The infrared light pattern may be a coherent infrared light pattern. The pattern illumination source may be configured for emitting light at a single wavelength, e.g. in the near infrared region. In other embodiments, the pattern illumination source may be adapted to emit light with a plurality of wavelengths, e.g. for allowing additional measurements in other wavelengths channels.

The infrared light pattern may comprise at least one regular and/or constant and/or periodic pattern such as a triangular pattern, a rectangular pattern, a hexagonal pattern or a pattern comprising further convex tilings. For example, the infrared light pattern is a hexagonal pattern, preferably a hexagonal infrared light pattern, preferably a 2/5 hexagonal infrared light pattern. Using a periodical 2/5 hexagonal pattern can allow distinguishing between artefacts and usable signal.

The infrared light pattern may comprise at least one point pattern. The infrared light pattern has a low point density. The number of infrared light spots is below or equal 4000 spots. The infrared light pattern may comprise equal to or less than 3000 spots, preferably equal to or less than 2000 spots. The infrared light pattern may have a low point density, in particular in comparison with other structured light techniques having typically a point density of 10k - 30k in a field of view of 55x38°. Using such a low point density may allow compensating for the above- mentioned diffraction loss. By decreasing the number of spots projected onto an object and/or a user, a contrast in the pattern image may be increased. Increasing the number of points would decrease the irradiance per point. The decreased number of spots may lead to an increase in irradiance of a spot and thus, to an increase in contrast in the pattern image of the projection of the infrared light pattern. The infrared light pattern may have a periodic point pattern with a reduced number of spots, wherein each of the spots has a high irradiance. Such a light pattern can ensure improved authentication using illumination sources and image generation unit behind a display. Moreover, the low number of spots can ensure complying with eye safety requirements and stability requirements. The allowed dose may be divided between the spots of the light pattern.

At least one of the infrared light spots may be associated with a beam divergence of 0.2° to 0.5°, preferably 0.1 ° to 0.3°. The term “beam divergence” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one measure of an increase in at least one diameter and/or at least one diameter equivalent, such as a radius, with a distance from an optical aperture from which the beam emerges. The measure may be an angle or an angle equivalent. In the context of the present invention, typically, a beam divergence may be determined at 1/e².

The pattern illumination source may comprise at least one pattern projector configured for generating the infrared light pattern. The pattern illumination source, e.g. the pattern projector, may comprise at least one emitter, in particular a plurality of emitters. The term “emitter” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one arbitrary device configured for providing at least one light beam. The light beam may generate the infrared light pattern. The emitter may comprise at least one element selected from the group consisting of at least one laser source such as at least one semi-conductor laser, at least one double heterostructure laser, at least one external cavity laser, at least one separate confinement heterostructure laser, at least one quantum cascade laser, at least one distributed Bragg reflector laser, at least one polariton laser, at least one hybrid silicon laser, at least one extended cavity diode laser, at least one quantum dot laser, at least one volume Bragg grating laser, at least one Indium Arsenide laser, at least one Gallium Arsenide laser, at least one transistor laser, at least 50 one diode pumped laser, at least one distributed feedback lasers, at least one quantum well laser, at least one interband cascade laser, at least one semiconductor ring laser, at least one vertical cavity surface emitting laser (VCSEL); at least one non-laser light source such as at least one LED or at least one light bulb. For example, the pattern projector comprises at least one VCSEL, preferably a plurality of VCSELs. The plurality of VCSELs may be arranged in at least one array, e.g. comprising a matrix of VCSELs. The VCSELs may be arranged on the same substrate, or on different substrates. The term “vertical-cavity surface-emitting laser” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a semiconductor laser diode configured for laser beam emission perpendicular with respect to a top surface. Examples for VCSELs can be found e.g. in en.wikipedia.org/wiki/Verticalcavity_surface-emitting_laser. VCSELs are generally known to the skilled person such as from WO 2017/222618 A. Each of the VCSELs is configured for generating at least one light beam. The VCSEL or the plurality of VCSELs may be configured for generating the desired spot number equal or below or equal 4000 spots, preferably, equal or below 3000 spots, more preferably equal or below 2000 spots. The plurality of generated spots may be associated with the infrared light pattern. The VCSELs may be configured for emitting light beams at a wavelength range from 800 to 1000 nm. For example, the VCSELs may be configured for emitting light beams at 808 nm, 850 nm, 940 nm, and/or 980 nm. Preferably the VCSELs emit light at 940 nm, since terrestrial sun radiation has a local minimum in irradiance at this wavelength, e.g. as described in CIE 085-1989 „Solar spectral Irradiance”.

The pattern illumination source may comprise at least one optical element configured for increasing, e.g. duplicating, the number of spots, e.g. the spots generated by the pattern projector. The pattern illumination source, particularly the optical element, may comprises at least one diffractive optical element (DOE) and/or at least one metasurface element. The DOE and/or the metasurface element may be configured for generating multiple light beams from a single incoming light beam. For example, a VCSEL projecting up to 2000 spots and an optical element comprising a plurality of metasurface elements may be used to duplicate the number of spots. Further arrangements, particularly comprising a different number of projecting VCSEL and/or at least one different optical element configured for increasing the number of spots may be possible. Other multiplication factors are possible. For example, a VCSEL or a plurality of VCSELs may be used and the generated laser spots may be duplicated by using at least one DOE.

The pattern illumination source may comprise at least one transfer device. The term “transfer device”, also denoted as “transfer system”, as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to one or more optical elements which are adapted to modify the light beam, particularly the light beam used for generating at least a portion of the infrared light pattern, such as by modifying one or more of a beam parameter of the light beam, a width of the light beam or a direction of the light beam. The transfer device may comprise at least one imaging optical device .The transfer device specifically may comprise one or more of: at least one lens, for example at least one lens selected from the group consisting of at least one focus-tunable lens, at least one aspheric lens, at least one spherical lens, at least one Fresnel lens; at least one diffractive optical element; at least one concave mirror; at least one beam deflection element, preferably at least one mirror; at least one beam splitting element, preferably at least one of a beam splitting cube or a beam splitting mirror; at least one multi-lens system; at least one holographic optical element; at least one meta optical element. Specifically, the transfer device comprises at least one refractive optical lens stack. Thus, the transfer device may comprise a multi-lens system having refractive properties. The term “flood illumination source” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one arbitrary device configured for providing substantially continuous spatial illumination. The term “flood light” as used herein, is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to substantially continuous spatial illumination, in particular diffuse and/or uniform illumination. The flood light has a wavelength in the infrared range, in particular in the near infrared range. The flood illumination source may comprise at least one LED or at least one VCSEL, preferably a plurality of VCSELs. The plurality of VCSELs may overlap to a uniform area. The term “substantially continuous spatial illumination” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to uniform spatial illumination, wherein areas of non-uniform are possible. The area, e.g. covering a user, a portion of the user and/or a face of the user, illuminated from the flood illumination source, may be contiguous. Power may be spread over a whole field of illumination. In contrast, illumination provided by the light pattern may comprise at least two contiguous areas, in particular a plurality of contiguous areas, and/or power may be concentrated in small (compared to the whole field of illumination) areas of the field of illumination. The infrared flood illumination may be suitable for illuminating a contiguous area, in particular one contiguous area. The infrared pattern illumination may be suitable for illuminating at least two contiguous areas.

The flood illumination source may illuminate a measurement area, such as a user, a portion of the user and/or a face of the user, with a substantially constant illumination intensity. The term “constant” as used herein, is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a time aspect during an exposure time. Flood light may vary temporally and/or may be substantially constant over time. The term “substantially constant” as used herein, is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a completely constant illumination and embodiments in which deviations from a constant illumination of < ± 10 %, preferably < ± 5 %, more preferably < ± 2 % are possible.

The emitting of the infrared flood light and the illumination of the infrared light pattern may be performed subsequently or at at least partially overlapping times. For example, the infrared flood light and the infrared light pattern may be emitted at the same time. For example, one of the flood light or the infrared light pattern may be emitted with a lower intensity compared to the other one. The pattern illumination source and the flood illumination source may comprise at least one VCSEL, preferably a plurality of VCSELs. The pattern illumination source may comprise a plurality of first VCSELs mounted on a first platform. The flood illumination source may comprise a plurality of second VCSELs mounted on a second platform. The second platform may be beside the first platform. The display device may comprise a heat sink. Above the heat sink a first increment comprising the first platform may be attached. Above the heat sink a second increment comprising the second platform may be attached. The second increment may be different from the first increment. Thus, the first platform may be more distant to the optical element configured for increasing, e.g. duplicating, the number of spots. The second platform may be closer to the optical element. The beam emitted from the second VCSEL may be defocused and thus, form overlapping spots. This leads to a substantially continuous illumination and, thus, to flood illumination.

The term “image generation unit” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one unit of the display device configured for generating at least one image. The image may be generated via a hardware and/or a software interface, which may be considered as the image generation unit. The term “image generation” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to capturing and/or generating and/or determining and/or recording at least one image by using the image generation unit. The image generation may comprise imaging and/or recording the image. The image generation may comprise capturing a single image and/or a plurality of images such as a sequence of images. For generating an image via a hardware and/or a software interface, the capturing and/or generating and/or determining and/or recording of the image may be caused and/or initiated by the hardware and/or the software interface. For example, the image generation may comprise recording continuously a sequence of images such as a video or a movie. The image generation may be initiated by a user action or may automatically be initiated, e.g. once the presence of at least one object or user within a field of view and/or within a predetermined sector of the field of view of the image generation unit is automatically detected. The term “field of view” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an angular extent of the observable world and/or at least one scene that may be captured or viewed by an optical system, such as the image generation unit. The field of view may, typically, be expressed in degrees and/or radians, and, exemplarily, may represent the total angle spanned by the image and/or viewable area.

The image generation unit may comprise at least one optical sensor, in particular at least one pixelated optical sensor. The image generation unit may comprise at least one CMOS sensor or at least one CCD chip. For example, the image generation unit may comprise at least one CMOS sensor, which may be sensitive in the infrared spectral range. The term “image” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to data recorded by using the optical sensor, such as a plurality of electronic readings from the CMOS or CCD chip. The image may comprise raw image data or may be a pre-processed image. For example, the pre-processing may comprise applying at least one filter to the raw image data and/or at least one background correction and/or at least one background subtraction.

For example, the image generation unit may comprise one or more of at least one monochrome camera e.g. comprising monochrome pixels, at least one color (e.g. RGB) camera e.g. comprising color pixels, at least one IR camera. The camera may be a CMOS camera. The camera may comprise at least one monochrome camera chip, e.g. a CMOS chip. The camera may comprise at least one color camera chip, e.g. an RGB CMOS chip. The camera may comprise at least one IR camera chip, e.g. an IR CMOS chip. For example, the camera may comprise monochrome, e.g. black and white, pixels and color pixels. The color pixels and the monochrome pixels may be combined internally in the camera. The camera generally may comprise a one-dimensional or two-dimensional array of image sensors, such as pixels.

As outlined, above, the image generation unit may be at least one camera. For example, the camera may be an internal and/or external camera of a device comprising the display device. As described in the above, the internal and/or external camera of the device may be accessed via a hardware and/or a software interface comprised by the display device, which is used as the image generation unit. In case, the device is or comprises a smartphone the image generating unit may be a front camera, such as a selfie camera, and/or back camera of the smartphone.

The image generation unit may have a field of view between 10°x10° and 75°x75°, preferably 55°x65°. The image generation unit may have a resolution below 2 MP, preferably between 0.3 MP and 1.5 MP.

The image generation unit may comprise further elements, such as one or more optical elements, e.g. one or more lenses. As an example, the optical sensor may be a fix-focus camera, having at least one lens which is fixedly adjusted with respect to the camera. Alternatively, however, the camera may also comprise one or more variable lenses which may be adjusted, automatically or manually. The camera may comprise at least one optical filter, e.g. at least one bandpass filter. The bandpass filter may be matched to the spectrum of the light emitters. Other cameras, however, are feasible.

The term “pattern image” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an image generated by the image generation unit while illuminating with the infrared light pattern, e.g. on an object and/or a user. The pattern image may comprise an image showing a user, in particular at least parts of the face of the user, while the user is being illuminated with the infrared light pattern, particularly on a respective area of interest comprised by the image. The pattern image may be generated by imaging and/or recording light reflected by an object and/or user which is illuminated by the infrared light pattern. The pattern image showing the user may comprise at least a portion of the illuminated infrared light pattern on at least a portion the user. For example, the illumination by the pattern illumination source and the imaging by using the optical sensor may be synchronized, e.g. by using at least one control unit of the display device.

The term “flood image” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an image generated by the image generation unit while illumination source is emitting infrared flood light, e.g. on an object and/or a user. The flood image may comprise an image showing a user, in particular the face of the user, while the user is being illuminated with the flood light. The flood image may be generated by imaging and/or recording light reflected by an object and/or user which is illuminated by the flood light. The flood image showing the user may comprise at least a portion of the flood light on at least a portion the user. For example, the illumination by the flood illumination source and the imaging by using the optical sensor may be synchronized, e.g. by using at least one control unit of the display device.

The image generation unit may be configured for imaging and/or recording the pattern image and the flood image at the same time or at different times. The image generation unit may be configured for imaging and/or recording the pattern image and the flood image at at least partially overlapping measurement areas or equivalents of the measurement areas.

The term “masking element” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one physical component that is used to block and/or shape light in a predetermined manner. The masking element may have at least one hole, particularly for generating at least one aperture, where the pattern illumination source and/or the flood illumination source are located. The respective aperture may be aligned with the respective element in a manner to shape the respective radiation profile. The masking element may not prevent the emittance of the radiation of the respective light source, but rather, by being placed directly in front of the light source, restrict the angle distribution of the emitted light, particularly in a manner that higher angles in respect to a surface normal of the masking element, particularly exceeding a predetermined value, are suppressed and/or blocked, particularly compared to a scenario in which no masking element is present. Particularly in this manner, the masking element may restrict the spread of the respective light parallel to the display, particularly to prevent a fanning out of a respective light beam. As a result, the light passes through a narrower area of the display compared to setups without a masking element. Thereby, light that may be internally reflected in the glass of the display may be reduced so that cross talk is suppressed. The masking element may block a portion of the infrared light pattern and/or a portion of the infrared flood light and may comprise at least one aperture.

Further, the masking element may be in contact with the pattern illumination source and/or the flood illumination source. Further, the masking element may be in contact with at least a part of a display covering the pattern illumination source and/or the flood illumination source. The masking element may be associated with a transmittance, in particular a hemispherical transmittance, below 50 %, preferably below 25 %, most preferably below 5 %. The term associated with a transmittance" may refer to the masking element having a transmittance. The term “hemispherical transmittance” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a degree of light passing through an object, specifically by evaluating an angular distribution comprising all angles at which light could hit the object.

The masking element may be configured for shaping at least one of: a radiation profile of the infrared light pattern; a radiation profile of the infrared flood light; particularly by blocking a portion of the respective light. The term “radiation profile” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a distribution of radiation intensity as a function of position and/or distance from a light source. The radiation profile may be used to describe the spatial characteristics of a radiation field, such a radiation field of light, particularly by describing at least one of: a shape; a size; a direction of the radiation beam. The radiation profile may, further, provide at least one item of information on the intensity of the radiation at different points in space. The term “blocking” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to the process of preventing and/or limiting the transmission of light through a material or system, particularly the masking element. The light may, particularly, be blocked by at least one of: an absorption process, a reflection process and/or a scattering process.

The radiation profile of the infrared light pattern may be shaped by the masking element in a manner that an internal reflection of the infrared light pattern in the display, particularly in a glass, specifically a cover glass, comprised by the display, is at least decreased, particularly when compared to a display device not having a masking element. By shaping the infrared light pattern by the masking element, an area illuminated by the infrared light pattern on the display and/or an opening angle of the infrared light pattern incident on the display may be decreased, particularly when compared to a display device not having a masking element. The radiation profile of the infrared flood light is shaped by the masking element in a manner that an internal reflection of the infrared flood light in the display, particularly in a glass, specifically a cover glass, comprised by the display, may be decreased. The term “shaping a radiation profile” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a process of modifying the spatial distribution of radiation emitted from a source, such as the pattern illumination source and/or the flood illumination source.

By shaping the infrared flood light by the masking element, an area illuminated by the infrared flood light on the display and/or an opening angle of the infrared flood light incident on the display may be decreased, particularly when compared to a display device not having a masking element.

The internal reflection may be decreased by blocking light incident on the display, particularly generated by the pattern illumination source and/or the flood illumination source; wherein the light incident on the display may have an angle distribution showing less angles with a high value in respect to a normal to the surface of the display due to a blocking of these angles by the masking element, particularly compared to a display device not having a masking element.

The masking element, particularly for shaping the radiation profile of the infrared light pattern and/or the radiation profile of the infrared flood light, may be or may comprise at least one aperture. The term “aperture” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one opening and/or at least one hole through which light travels. The masking element may block at least a first portion of the infrared light pattern and/or the infrared flood light, particularly the portion of the light that is not incident on the aperture. A second portion of the respective light that is incident on the aperture may transfer through the masking element, particularly unhindered. Particularly thereby, the respective radiation profile may be shaped.

The masking element may comprise at least one of: silicone; a metal coating; a metal plate; a plastic plate and/or a plastic sheet; at least one composite material. The masking element may be and/or may comprise at least one material that absorbs light having at least one wavelength that may be detected by the image generation unit. A wavelength range detected by the image generation unit may be defined by at least one associated filter element, such as a bandpass filter. The masking element may be covered at least partially by the display. The masking element may be arranged between the display and at least one of the pattern illumination source, the image generation unit, the flood illumination source or a combination thereof. Particularly at least one, particularly exactly one, aperture may be arranged in line with the pattern illumination source and/or the image generation unit.

The display may comprise at least one of: a display panel, particularly comprising a plurality of pixels and/or a plurality of transistors; a glass, specifically a cover glass, particularly configured for covering the display panel.

The term “display” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to an arbitrary shaped device configured for displaying an item of information. The item of information may be arbitrary information such as at least one image, at least one diagram, at least one histogram, at least one graphic, text, numbers, at least one sign, an operating menu, and the like. The display may be or may comprise at least one display panel. The display may have an arbitrary shape, e.g. a rectangular shape. The display may be a front display of the device.

The display, specifically the display panel, may be or may comprise at least one organic lightemitting diode (OLED) display and/or at least one quantum-dot light emitting diode (QLED). As used herein, the term “organic light emitting diode” is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a lightemitting diode (LED) in which an emissive electroluminescent layer is a film of organic compound configured for emitting light in response to an electric current. The OLED display may be configured for emitting visible light. As used herein, the term “organic light emitting diode” is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a display technology that utilizes semiconductor particles called quantum dots in order to produce colors on a display. These quantum dots may emit a plurality of different colors of light depending on their size when excited by light. By using a combination of red, green and/or blue quantum dots, a QLED display may display a wide range of colors with high brightness and color accuracy.

The display may be at least partially transparent. The display may be at least partially transparent in at least one continuous areas covering the pattern illumination source, the flood illumination source and/or the image generation unit.

The display may be at least partially transparent in at least one continuous areas in a manner that at least one of:

- the infrared light pattern incident on the continuous areas traverses the display while being illuminated from the pattern illumination source;

- the infrared flood light incident on the continuous areas traverses the display while being illuminated from the flood illumination source; user light, generated by the infrared light pattern and/or the infrared flood light incident on a user, incident on the continuous areas traverses the display for impinging on the image generation unit.

The term “at least partially transparent” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a property of the display to allow light, in particular of a certain wavelength range, e.g. in the infrared spectral region, in particular in the near infrared spectral region, to pass at least partially through. For example, the display may be semitransparent in the near infrared region. For example, the display may have a transparency of 20 % to 50 % in the near infrared region. The display may have a different transparency for differing wavelength ranges. The present invention may propose an display device comprising the image generation unit and two illumination sources that can be placed behind the display of a device. The transparent area(s) of the display can allow for operation of the display device behind the display.

The display can be an at least partially transparent display, as described above. The partially transparent contiguous area of the display may be associated with a first pixel density value (Pixels per inch (PPI)), and a further area of the display may be associated with a second pixel density value. The first pixel density value may be lower than the second pixel density value. The transmission of light through the contiguous area may be higher compared to the transmission through the further area. The first pixel density value may be equal or below 450 PPI, preferably between 300 to 440 PPI, more preferably between 350 to 450 PPI. The first pixel density value may be constant over the entire contiguous area with a maximum deviation thereof of 20 %, or preferably 10 %. The second pixel density value may be between 400 to 500 PPI, preferably between 450 to 500 PPI.

The display device may be selected from the group consisting of: a television device; a game console; a personal computer; a mobile device, particularly a cell phone, and/or a smart phone, and/or, and/or a tablet computer, and/or a laptop, and/or a tablet, and/or a virtual reality device, and/or a wearable, such as a smart watch; or another type of portable computer.

The at least partially transparent continuous area of the display may comprise a first area and a second area. The first area may be associated with a first number of transistors configured for controlling at least one pixel and the second area may be associated with a second number of transistors configured for controlling at least one pixel, and wherein the first number of transistors may be smaller than the second number of transistors. The first number of transistors and/or the second number of transistors may refer to or be a density of the transistors.

The term “pixel” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a picture unit, particularly the smallest picture unit, that represents an addressable element. The entirety of the pixels may represent the display. A pixel may be manipulated by changing its color, brightness and/or contrast or the like. Particularly for manipulating the pixel, the pixel may be driven by at least one transistor, exemplarily a transistor the controls a current required for driving the pixel. Typically, a thin-film transistor may be used for driving the pixel. TFTs may preferably be used in a flat-panel display.

The masking element at least may attenuate at least one of:

- the infrared light pattern;

- the infrared flood light; incident on the second area, particularly by blocking the respective light. The first area may be an enclosed area, particularly a fully enclosed area, wherein the second area may be an enclosing area, particularly a fully enclosing area. The second area may be enclosing the first area. The second area may correspond to the outer area of the at least one partially transparent continuous area.

Thereby, a flickering of the display may be prevented. By arranging a transistor in the second area, the transistor may be shielded from light, particularly the infrared light pattern and/or the infrared flood light. Particularly as this light may influences the transistors and, exemplarily, trigger the light emission in the emission layer, false driving signal for a pixel associated with the transistor may be prevented.

The display device may be configured for authenticating a user of the display device to perform at least one operation on the device that requires authentication, wherein the display device may comprise at least one authentication unit configured for performing at least one authentication process of a user using the flood image and the pattern image. The authentication unit may be configured for using a facial recognition authentication process operating on the flood image, the pattern image and/or extracted material data, particularly derived from the pattern image.

The term “authenticating” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to verifying an identity of a user. Specifically, the authentication may comprise distinguishing between the user from other humans or objects, in particular between authorized access from non-authorized accesses. The authentication may comprise verifying identity of a respective user and/or assigning identity to a user. The authentication may comprise generating and/or providing identity information, e.g. to other devices or units such as to at least one authorization unit for authorization for providing access to the device. The identify information may be proofed by the authentication. For example, the identity information may be and/or may comprise at least one identity token. In case of successful authentication an image of a face recorded by the image generation unit may be verified to be an image of the user’s face and/or the identity of the user is verified. The authenticating may be performed using at least one authentication process. The authentication process may comprise a plurality of steps such as at least one face detection on the flood image and at least one identification step in which an identity is assigned to the detected face and/or at least one identity check and/or verifying an identity of the user is performed.

The term “authentication unit” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to at least one unit configured for performing at least one authentication process of a user. The authentication unit may be or may comprise at least one processor. The processor may be an arbitrary logic circuitry configured for performing basic operations of a computer or system, and/or, generally, to a device which is configured for performing calculations or logic operations. In particular, the processor may be configured for processing basic instructions that drive the computer or system. As an example, the processor may comprise at least one arithmetic logic unit (ALU), at least one floating-point unit (FPU), such as a math co-processor or a numeric co-processor, a plurality of registers, specifically registers configured for supplying operands to the ALU and storing results of operations, and a memory, such as an L1 and L2 cache memory. In particular, the processor may be a multi-core processor. Specifically, the processor may be or may comprise a central processing unit (CPU). Additionally or alternatively, the processor may be or may comprise a microprocessor, thus specifically the processor’s elements may be contained in one single integrated circuitry (IC) chip. Additionally or alternatively, the processor may be or may comprise one or more application-specific integrated circuits (ASICs) and/or one or more field-programmable gate arrays (FPGAs) and/or one or more tensor processing unit (TPU) and/or one or more chip, such as a dedicated machine learning optimized chip, or the like. The processor specifically may be configured, such as by software programming, for performing one or more evaluation operations. At least one or any component of a computer program configured for performing the authentication process may be executed by the processing device. Alternatively or in addition, the authentication unit may be or may comprise a connection interface. The connection interface may be configured to transfer data from the device to a remote device; or vice versa. At least one or any component of a computer program configured for performing the authentication process may be executed by the remote device.

For example, the authentication unit may perform at least one face detection using the flood image. The face detection may be performed locally on the device. Face identification, i.e. assigning an identity to the detected face, however, may be performed remotely, e.g. in the cloud, e.g. especially when identification needs to be done and not only verification. User templates can be stored at the remote device, e.g. in the cloud, and would not need to be stored locally. This can be an advantage in view of storage space and security. The authentication unit may be configured for identifying the user based on the flood image. Particularly therefore, the authentication unit may forward data to a remote device. Alternatively or in addition, the authentication unit may perform the identification of the user based on the flood image, particularly by running an appropriate computer program having a respective functionality. The term “identifying” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to assigning an identity to a detected face and/or at least one identity check and/or verifying an identity of the user.

The authentication process may comprise a plurality of steps. For example, the authentication process may comprise performing at least one face detection. The face detection step may comprise analyzing the flood image. In addition, for example, the authentication process may comprise identifying. The identifying may comprise assigning an identity to a detected face and/or at least one identity check and/or verifying an identity of the user. The identifying may comprise performing a face verification of the imaged face to be the user’s face. The identifying the user may comprise matching the flood image, e.g. showing a contour of parts of the user, in particular parts of the user’s face, with a template. The identifying of the user may comprise determining if the imaged face is the face of the user, in particular if the imaged face corresponds to at least one image of the user’s face stored in at least one memory, e.g. of the device.

The analyzing of the flood image may comprise one or more of the following: a filtering; a selection of at least one region of interest; a formation of a difference image between the flood image and at least one offset; an inversion of flood image; a background correction; a decomposition into color channels; a decomposition into hue; saturation; and brightness channels; a frequency decomposition; a singular value decomposition; applying a Canny edge detector; applying a Laplacian of Gaussian filter; applying a Difference of Gaussian filter; applying a Sobel operator; applying a Laplace operator; applying a Scharr operator; applying a Prewitt operator; applying a Roberts operator; applying a Kirsch operator; applying a high-pass filter; applying a low-pass filter; applying a Fourier transformation; applying a Radon- transformation; applying a Hough-transformation; applying a wavelet-transformation; a thresholding; creating a binary image. The region of interest may be determined manually by a user or may be determined automatically, such as by recognizing the user within the image. In particular, the analyzing of the flood image may comprise using at least one image recognition technique, in particular a face recognition technique. An image recognition technique comprises at least one process of identifying the user in an image. The image recognition may comprise using at least one technique selected from the technique consisting of: color-based image recognition, e.g. using features such as template matching; segmentation and/or blob analysis e.g. using size, or shape; machine learning and/or deep learning e.g. using at least one convolutional neural network. The analyzing of the flood image may comprise determining a plurality of facial features. The analyzing may comprise comparing, in particular matching, the determined facial features with template features. The template features may be features extracted from at least one template. The template may be or may comprise at least one image generated in an enrollment process, e.g. when initializing the device. Template may be an image of an authorized user. The template features and/or the facial feature may comprise a vector. Matching of the features may comprise determining a distance between the vectors. The identifying of the user may comprise comparing the distance of the vectors to a least one predefined limit, wherein the user is successfully identified in case the distance is < the predefined limit at least within tolerances. The user declining and/or rejected otherwise.

For example, the image recognition may comprise using at least one model, in particular a trained model comprising at least one face recognition model. The analyzing of the flood image may be performed by using a face recognition system, such as FaceNet, e.g. as described in Florian Schroff, Dmitry Kalenichenko, James Philbin, “FaceNet: A Unified Embedding for Face Recognition and Clustering”, arXiv: 1503.03832. The trained model may comprises at least one convolutional neural network. For example, the convolutional neural network may be designed as described in M. D. Zeiler and R. Fergus, “Visualizing and understanding convolutional networks”, CoRR, abs/1311.2901 , 2013, or C. Szegedy et al., “Going deeper with convolutions”, CoRR, abs/1409.4842, 2014. For more details with respect to convolutional neural network for the face recognition system reference is made to Florian Schroff, Dmitry Kalenichenko, James Philbin, “FaceNet: A Unified Embedding for Face Recognition and Clustering”, arXiv: 1503.03832. As training data labelled image data from an image database may be used. Specifically, labeled faces may be used from one or more of G. B. Huang, M. Ramesh, T. Berg, and E. Learned-Miller, “Labeled faces in the wild: A database for studying face recognition in unconstrained environments”, Technical Report 07-49, University of Massachusetts, Amherst, October 2007, the Youtube® Faces Database as described in L. Wolf, T. Hassner, and I. Maoz, “Face recognition in unconstrained videos with matched background similarity”, in IEEE Conf, on CVPR, 2011 , or Google® Facial Expression Comparison dataset. The training of the convolutional neural network may be performed as described in Florian Schroff, Dmitry Kalenichenko, James Philbin, “FaceNet: A Unified Embedding for Face Recognition and Clustering”, arXiv: 1503.03832.

The authentication unit may be further configured for extracting material data from the pattern image. Particularly therefore, the authentication unit may forward data to a remote device. Alternatively or in addition, the authentication unit may perform the material determination based on the pattern image, particularly by running an appropriate computer program having a respective functionality. Particularly by considering the material as a parameter for validating the authentication process, the authentication process may be robust against being outwitted by using a recorded image of the user. The authentication unit may be configured for extracting the material data from the pattern image by beam profile analysis of the light spots. With respect to beam profile analysis reference is made to WO 2018/091649 A1 , WO 2018/091638 A1 and WO 2018/091640 A1 , the full content of which is included by reference. * Beam profile analysis can allow for providing a reliable classification of scenes based on a few light spots. Each of the light spots of the pattern image may comprise a beam profile. As used herein, the term “beam profile” may generally refer to at least one intensity distribution of the light spot on the optical sensor as a function of the pixel. The beam profile may be selected from the group consisting of a trapezoid beam profile; a triangle beam profile; a conical beam profile and a linear combination of Gaussian beam profiles.

The authentication unit may be configured for outsourcing at least one step of the authentication process, such as the identifying of the user, and/or at least one step of the validation of the authentication process, such as the consideration of the material data, to a remote device, specifically a server and/or a cloud server. The device and the remote device may be part of a computer network, particularly the internet. Thereby, the device may be used as a field device that is used by the user for generating data required in the authentication process and/or its validation. The device may transmit the generated data and/or data associated to an intermediate step of the authentication process and/or its validation to the remote device. In such a scenario, the authentication unit may be and/or may comprise a connection interface configured for transmitting information to the remote device. Data generated by the remote device used in the authentication process and/or its validation may further be transmitted to the device. This data may be received by the connection interface comprised by the device. The connection interface may specifically be configured for transmitting or exchanging information. In particular, the connection interface may provide a data transfer connection. As an example, the connection interface may be or may comprise at least one port comprising one or more of a network or internet port, a USB-port, and a disk drive.

It is emphasized that data from the display device may be transmitted to a specific remote device depending on at least one circumstance, such as a date, a day, a load of the specific remote device, and so on. The specific remote device may not be selected by the field device. Rather a further device may select to which specific remote device the data may be transmitted. The authentication process and and/or the generation of validation data may involve a use of several different entities of the remote device. At least one entity may generate intermediate data and transmit the intermediate data to at least one further entity.

Extracting material data from the pattern image may comprise generating the material type and/or data derived from the material type. Preferably, extracting material data may be based on the pattern image. Material data may be extracted by using at least one model. Extracting material data may include providing the pattern image to a model and/or receiving material data from the model. Providing the image to a model may comprise and may be followed by receiving the pattern image at an input layer of the model or via a model loss function. The model may be a data-driven model. Data-driven model may comprise a convolutional neural network and/or an encoder decoder structure such as an autoencoder. Other examples for generating a representation may be FFT, wavelets, deep learning, like CNNs, energy models, normalizing flows, GANs, vision transformers, or transformers used for natural language processing, Autoregressive Image Modeling, Normalizing Flows, Deep Autoencoders, Deep Energy-Based Models. Supervised or unsupervised schemes may be applicable to generate a representation, also embedding in e.g. cosine or Euclidian metric in ML language. The data- driven model may be parametrized according to a training data set including at least one image and material data, preferably at least one pattern image and material data. In another embodiment, extracting material data may include providing the image to a model and/or receiving material data from the model. In another embodiment, the data-driven model may be trained according to a training data set including at least one image and material data. In another embodiment, the data-driven model may be parametrized according to a training data set including at least one image and material data. The data-driven model may be parametrized according to a training data set to receive the image and provide material data based on the received image. The data-driven model may be trained according to a training data set to receive the image and provide material data as output based on the received image. The training data set may comprise at least one image and material data, preferably material data associated with the at least one image. The image may comprise a representation of the image. The representation may be a lower dimensional representation of the image. The representation may comprise at least a part of the data or the information associated with the image. The representation of an image may comprise a feature vector. In an embodiment, determining a representation, in particular a lower-dimensional representation may be based on principal component analysis (PCA) mapping or radial basis function (RBF) mapping. Determining a representation may also be referred to as generating a representation. Generating a representation based on PCA mapping may include clustering based on features in the pattern image and/or partial image. Additionally or alternatively, generating a representation may be based on neural network structures suitable for reducing dimensionality. Neural network structures suitable for reducing dimensionality may comprise encoder and/or decoder. In an example, neural network structure may be an autoencoder. In an example, neural network structure may comprise a convolutional neural network (CNN). The CNN may comprise at least one convolutional layer and/or at least one pooling layer. CNNs may reduce the dimensionality of a partial image and/or an image by applying a convolution, e.g. based on a convolutional layer, and/or by pooling. Applying a convolution may be suitable for selecting feature related to material information of the pattern image.

A model may be suitable for determining an output based on an input. In particular, model may be suitable for determining material data based on an image as input. A model may be a deterministic model, a data-driven model or a hybrid model. The deterministic model, preferably, reflects physical phenomena in mathematical form, e.g., including first-principles models. A deterministic model may comprise a set of equations that describe an interaction between the material and the patterned electromagnetic radiation thereby resulting in a condition measure, a vital sign measure or the like. A data-driven model may be a classification model. A hybrid model may be a classification model comprising at least one machine-learning architecture with deterministic or statistical adaptations and model parameters. Statistical or deterministic adaptations may be introduced to improve the quality of the results since those provide a systematic relation between empiricism and theory. In an embodiment, the data-driven model may be a classification model. The classification model may comprise at least one machinelearning architecture and model parameters. For example, the machine-learning architecture may be or may comprise one or more of: linear regression, logistic regression, random forest, piecewise linear, nonlinear classifiers, support vector machines, naive Bayes classifications, nearest neighbors, neural networks, convolutional neural networks, generative adversarial networks, support vector machines, or gradient boosting algorithms or the like. In the case of a neural network, the model can be a multi-scale neural network or a recurrent neural network (RNN) such as, but not limited to, a gated recurrent unit (GRU) recurrent neural network or a long short-term memory (LSTM) recurrent neural network. The data-driven model may be parametrized according to a training data set. The data-driven model may be trained based on the training data set. Training the model may include parametrizing the model. The term training may also be denoted as learning. The term specifically may refer, without limitation, to a process of building the classification model, in particular determining and/or updating parameters of the classification model. Updating parameters of the classification model may also be referred to as retraining. Retraining may be included when referring to training herein. In an embodiment, the training data set may include at least one image and material information.

Extracting material data from the image with a data-driven model may comprise providing the image to a data-driven model. Additionally or alternatively, extracting material data from the image with a data-driven model may comprise may comprise generating an embedding associated with the image based on the data-driven model. An embedding may refer to a lower dimensional representation associated with the image such as a feature vector. Feature vector may be suitable for suppressing the background while maintaining the material signature indicating the material data. In this context, background may refer to information independent of the material signature and/or the material data. Further, background may refer to information related to biometric features such as facial features. Material data may be determined with the data-driven model based on the embedding associated with the image. Additionally or alternatively, extracting material data from the image by providing the image to a data-driven model may comprise transforming the image into material data, in particular a material feature vector indicating the material data. Hence, material data may comprise further the material feature vector and/or material feature vector may be used for determining material data.

The authentication process may be validated based on the extracted material data. In an embodiment, the validating based on the extracted material data may comprise determining if the extracted material data corresponds a desired material data. Determining if extracted material data matches the desired material data may be referred to as validating. Allowing or declining the user and/or object to perform at least one operation on the device that requires authentication based on the material data may comprise validating the authentication or authentication process. Validating may be based on material data and/or image. Determining if the extracted material data corresponds a desired material data may comprise determining a similarity of the extracted material data and the desired material data. Determining a similarity of the extracted material data and the desired material data may comprise comparing the extracted material data with the desired material data. Desired material data may refer to predetermined material data. In an example, desired material data may be skin. It may be determined if material data may correspond to the desired material data. In the example, material data may be non-skin material or silicon. Determining if material data corresponds to a desired material data may comprise comparing material data with desired material data. A comparison of material data with desired material data may result in a allowing and/or declining the user and/or object to perform at least one operation that requires authentication. In the example, skin as desired material data may be compared with non-skin material or silicon as material data and the result may be declination since silicon or non-skin material may be different from skin.

The authentication process or its validation may include generating at least one feature vector from the material data and matching the material feature vector with associate reference template vector for material.

The authentication unit may be configured for authenticating the user in case the user can be identified and/or if the material data matches the desired material data. The device may comprise at least one authorization unit configured for allowing the user to perform at least one operation on the device, e.g. unlocking the device, in case of successful authentication of the user or declining the user to perform at least one operation on the device in case of nonsuccessful authentication. Thereby, the user may become aware of the result of the authentication.

In a further aspect, a method for authenticating a user of a display device to perform at least one operation on the display device that requires authentication is disclosed.

The method comprises the following steps: a. generating at least one pattern image by using at least one image generation unit of the display device, wherein the pattern image shows the user while the user is being illuminated with at least one infrared light pattern generated by at least one pattern illumination source of the display device, b. generating at least one flood image by using the image generation unit of the display device, wherein the flood image shows the user while the user is being illuminated with infrared flood light generated by at least one pattern illumination source of the display device, c. providing an item of identification information on the user based on the flood image, particularly by using at least one authentication unit of the device, d. providing an item of material information based on the at least one pattern image, particularly by using the authentication unit; and e. allowing the user to perform at least one operation on the display device that requires authentication based on the item of identification information and item of material information.

The method steps may be performed in the given order or may be performed in a different order. Further, one or more additional method steps may be present which are not listed. Further, one, more than one or even all of the method steps may be performed repeatedly. For details, options and definitions, reference may be made to the display device and the device as discussed above. Thus, specifically, the method may comprise using the device according to the present invention, such as according the above or given in further detail below. Reference may, therefore, be made to any further aspect of the present disclosure.

For providing the item of identification information, the method may comprise using a facial recognition authentication process operating on the flood image, the pattern image and/or extracted material data.

The pattern image and/or the image showing the user while the user is being illuminated with the infrared flood light may be showing at least a portion of a face of the user. Providing an item of identification information may comprise matching the flood image with a template.

All described method steps may be performed by using the device. Therefore, the single processing device may be configured to exclusively perform at least one computer program, in particular at least one line of computer program code configured to execute at least one algorithm, as used in at least one of the embodiments of the method according to the present invention. Herein, the computer program as executed on the single processing device may comprise all instructions causing the computer to carry out the method. Alternatively, or in addition, at least one method step may be performed by using at least one remote device, especially selected from at least one of a server or a cloud server, particularly when the device and the remote device may be part of a computer network. In this case, the computer program may comprise at least one remote component to be executed by the at least one remote processing device to carry out the at least one method step. The remote component may have the functionality of performing the identifying of the user and/or the extraction of the material data. Further, the computer program may comprise at least one interface configured to forward to and/or receive data from the at least one remote component of the computer program.

The method may comprise allowing or declining the user to perform at least one operation on the device. In an embodiment, allowing or declining the user to perform at least one operation on the device that requires authentication based on the material data may include allowing the user to perform at least one operation on the device that requires authentication if the material data matches desired material data and/or authentication may be successful. Desired material data may be predetermined material data. Authentication may be successful if the user can be identified and/or if the material data matches desired material data. Further, allowing or declining the object to perform at least one operation on the device that requires authentication based on the material data may include declining to perform at least one operation on the device that requires authentication if the material data does not match desired material data and/or authentication may be unsuccessful. Authentication may be unsuccessful if the pattern image cannot be matched with an image template and/or if the material data does not match the desired material data.

At least one operation on the device that requires authentication may be access to the device, e.g. unlocking the device, and/or access to an application, preferably associated with the device and/or access to a part of an application, preferably associated with the device. In an embodiment, allowing the user to access a resource may include allowing the user to perform at least one operation with a device and/or system. The resource may be a device, a system, a function of a device, a function of a system and/or an entity. Additionally and/or alternatively, allowing the user to access a resource may include allowing the user to access an entity. The entity may be physical entity and/or virtual entity. The virtual entity may be a database for example. The physical entity may be an area with restricted access. The area with restricted access may be one of the following: security areas, rooms, apartments, vehicles, parts of the before mentioned examples, or the like. Device and/or system may be locked. The device and/or the system may only be unlocked by authorized user.

The term “user” as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a person intended to and/or using the device.

The method may be computer-implemented. The term "computer implemented " as used herein is a broad term and is to be given its ordinary and customary meaning to a person of ordinary skill in the art and is not to be limited to a special or customized meaning. The term specifically may refer, without limitation, to a method involving at least one computer and/or at least one computer network. The computer and/or computer network may comprise at least one processor which is con-figured for performing at least one of the method steps of the method according to the present invention. Specifically, each of the method steps is performed by the computer and/or computer network. The method may be performed completely automatically, specifically without user interaction.

In a further aspect, a computer program is disclosed, which comprises instructions which, when the program is executed by the display device, cause the display device to perform the method according to any one of the preceding embodiments referring to a method. Specifically, the computer program may be stored on a computer-readable data carrier and/or on a computer- readable storage medium. The computer program may be executed on at least one processor comprised by the display device and/or the device. The computer program may generate input data by accessing and/or controlling at least one unit of the display device and/or the device, such as the pattern illumination source and/or the flood illumination source and/or the image generation unit. The computer program may generate outcome data based on the input data, particularly by using the authentication unit.

As used herein, the terms “computer-readable data carrier” and “computer-readable storage medium” specifically may refer to non-transitory data storage means, such as a hardware storage medium having stored thereon computer-executable instructions. The stored computerexecutable instruction may be associate with the computer program. The computer-readable data carrier or storage medium specifically may be or may comprise a storage medium such as a random-access memory (RAM) and/or a read-only memory (ROM).

Thus, specifically, one, more than one or even all of method steps a. to e. as indicated above may be performed by using a computer or a computer network, preferably by using a computer program.

Further disclosed and proposed herein is a computer program product having program code means, in order to perform the method according to the present invention in one or more of the embodiments enclosed herein when the program is executed on a computer or computer network. Specifically, the program code means may be stored on a computer-readable data carrier and/or on a computer-readable storage medium.

Further disclosed and proposed herein is a data carrier having a data structure stored thereon, which, after loading into a computer or computer network, such as into a working memory or main memory of the computer or computer network, may execute the method according to one or more of the embodiments disclosed herein.

Further disclosed and proposed herein is a computer program product with program code means stored on a machine-readable carrier, in order to perform the method according to one or more of the embodiments disclosed herein, when the program is executed on a computer or computer network. As used herein, a computer program product refers to the program as a tradable product. The product may generally exist in an arbitrary format, such as in a paper format, or on a computer-readable data carrier and/or on a computer-readable storage medium. Specifically, the computer program product may be distributed over a data network.

Further disclosed and proposed herein is a non-transient computer-readable medium including instructions that, when executed by one or more processors, cause the one or more processors to perform the method according to one or more of the embodiments disclosed herein. Finally, disclosed and proposed herein is a modulated data signal which contains instructions readable by a computer system or computer network, for performing the method according to one or more of the embodiments disclosed herein.

Referring to the computer-implemented aspects of the invention, one or more of the method steps or even all of the method steps of the method according to one or more of the embodiments disclosed herein may be performed by using a computer or computer network. Thus, generally, any of the method steps including provision and/or manipulation of data may be per-formed by using a computer or computer network. Generally, these method steps may include any of the method steps, typically except for method steps requiring manual work, such as providing the samples and/or certain aspects of performing the actual measurements.

Specifically, further disclosed herein are: a computer or computer network comprising at least one processor, wherein the processor is adapted to perform the method according to one of the embodiments described in this description, a computer loadable data structure that is adapted to perform the method according to one of the embodiments described in this description while the data structure is being executed on a computer, a computer program, wherein the computer program is adapted to perform the method according to one of the embodiments described in this description while the program is being executed on a computer, a computer program comprising program means for performing the method according to one of the embodiments described in this description while the computer program is being executed on a computer or on a computer network, a computer program comprising program means according to the preceding embodiment, wherein the program means are stored on a storage medium readable to a computer, a storage medium, wherein a data structure is stored on the storage medium and wherein the data structure is adapted to perform the method according to one of the embodiments described in this description after having been loaded into a main and/or working storage of a computer or of a computer network, and a computer program product having program code means, wherein the program code means can be stored or are stored on a storage medium, for performing the method ac-cording to one of the embodiments described in this description, if the program code means are executed on a computer or on a computer network.

As used herein, the terms “have”, “comprise” or “include” or any arbitrary grammatical variations thereof are used in a non-exclusive way. Thus, these terms may both refer to a situation in which, besides the feature introduced by these terms, no further features are present in the entity described in this context and to a situation in which one or more further features are present. As an example, the expressions “A has B”, “A comprises B” and “A includes B” may both refer to a situation in which, besides B, no other element is present in A (i.e. a situation in which A solely and exclusively consists of B) and to a situation in which, besides B, one or more further elements are present in entity A, such as element C, elements C and D or even further elements.

Further, it shall be noted that the terms “at least one”, “one or more” or similar expressions indicating that a feature or element may be present once or more than once typically are used only once when introducing the respective feature or element. In most cases, when referring to the respective feature or element, the expressions “at least one” or “one or more” are not repeated, nonwithstanding the fact that the respective feature or element may be present once or more than once.

Further, as used herein, the terms "preferably", "more preferably", "particularly", "more particularly", "specifically", "more specifically" or similar terms are used in conjunction with optional features, without restricting alternative possibilities. Thus, features introduced by these terms are optional features and are not intended to restrict the scope of the claims in any way. The invention may, as the skilled person will recognize, be performed by using alternative features. Similarly, features introduced by "in an embodiment of the invention" or similar expressions are intended to be optional features, without any restriction regarding alternative embodiments of the invention, without any restrictions regarding the scope of the invention and without any restriction regarding the possibility of combining the features introduced in such way with other optional or non-optional features of the invention.

The present disclosure exhibits several advantages, discussed in the following.

By limiting an angular emission profile of at least one of the disclosed light sources or any of the disclosed light sources, large angles to the surface normal of the display may be suppressed, which, typically, may allow a large amount of the light to be reflected internally in the display (e.g. described by the Fresnel equations) and, thereby, travel further distances, particularly even to the image generation unit. The angle profile may, typically advantageously, be limited as narrow as possible, specifically to reduce cross talk, which may be generated by the internally reflected light.

A mechanical aperture may be placed in front of at least one or any of the light sources in a manner that the large angles of the radiation profile may be cut off, particularly as described above. Thereby, the emitted power at these cut-off angles may significantly be reduced. The presented solution may be used to suppress cross-talk

By placing the transistors of the display, particularly the TFTs, on an outer perimeter of the semi-transparent area of the display, the masking element may block the light incident on the transistors from at least one of the light sources or any of the light source mentioned herein. Particularly thereby, the transistors may be shielded, which may prevent flickering. Overall, in the context of the present invention, the following embodiments are regarded as preferred:

In an embodiment, a display device is disclosed, the display device may comprise: at least one pattern illumination source configured for emitting an infrared light pattern, at least one flood illumination source configured for emitting infrared flood light, at least one image generation unit configured for generating at least one pattern image while the pattern illumination source is emitting the infrared light pattern and configured for generating at least one flood image while the flood illumination source is emitting infrared flood light, at least one masking element configured for covering at least one contiguous area around the flood illumination source and/or the pattern illumination source, at least one display configured for displaying content, wherein the display covers at least partially the pattern illumination source, the flood illumination source, the masking element and/or the image generation unit.

In an embodiment, the masking element may be in contact with the pattern illumination source and/or the flood illumination source.

In an embodiment, the masking element may be in contact with at least a part of a display covering the pattern illumination source and/or the flood illumination source.

In an embodiment, the masking element may be associated with a transmittance, in particular a hemispherical transmittance, below 50 %, preferably below 25 %, most preferably below 5 %.

In an embodiment, the masking element may block a portion of the infrared light pattern and/or a portion of the infrared flood light and comprises at least one aperture.

In an embodiment, the masking element may be configured for shaping at least one of: a radiation profile of the infrared light pattern; a radiation profile of the infrared flood light; particularly by blocking a portion of the respective light.

In an embodiment, the radiation profile of the infrared light pattern may be shaped by the masking element in a manner that an internal reflection of the infrared light pattern in the display, particularly in a glass, specifically a cover glass, comprised by the display, is decreased.

In an embodiment, by shaping the infrared light pattern by the masking element, an area illuminated by the infrared light pattern on the display and/or an opening angle of the infrared light pattern incident on the display may be decreased, particularly when compared to a display device not having a masking element.

In an embodiment, the radiation profile of the infrared flood light may be shaped by the masking element in a manner that an internal reflection of the infrared flood light in the display, particularly in a glass, specifically a cover glass, comprised by the display, is decreased.

In an embodiment, by shaping the infrared flood light by the masking element, an area illuminated by the infrared flood light on the display and/or an opening angle of the infrared flood light incident on the display may be decreased, particularly when compared to a display device not having a masking element.

In an embodiment, the internal reflection may be decreased by blocking light incident on the display, particularly generated by the pattern illumination source and/or the flood illumination source; wherein light incident on the display has an angle distribution showing less angles with a high value in respect to a normal to the surface of the display due to a blocking of these angles by the masking element, particularly compared to a display device not having a masking element.

In an embodiment, the masking element, particularly for shaping the radiation profile of the infrared light pattern and/or the radiation profile of the infrared flood light, may be or may comprise at least one aperture.

In an embodiment, the masking element may comprise at least one of:

- silicone; a metal coating; a metal plate; a plastic plate and/or a plastic sheet; at least one composite material.

In an embodiment, the masking element may be covered at least partially by the display.

In an embodiment, the masking element may be arranged between the display and at least one of the pattern illumination source, the image generation unit, the flood illumination source or a combination thereof.

In an embodiment, the display may be at least partially transparent in at least one continuous areas covering the pattern illumination source, the flood illumination source and/or the image generation unit.

In an embodiment, the display may be at least partially transparent in at least one continuous areas in a manner that at least one of: - the infrared light pattern incident on the continuous areas traverses the display while being illuminated from the pattern illumination source;

- the infrared flood light incident on the continuous areas traverses the display while being illuminated from the flood illumination source; user light, generated by the infrared light pattern and/or the infrared flood light incident on a user, incident on the continuous areas traverses the display for impinging on the image generation unit.

In an embodiment, the at least partially transparent continuous area of the display may comprise a first area and a second area.

In an embodiment, the first area may be associated with a first number of transistors configured for controlling at least one pixel and the second area is associated with a second number of transistors configured for controlling at least one pixel, and wherein the first number of transistors is smaller than the second number of transistors.

In an embodiment, the first number of transistors and/or the second number of transistors may refer to a density of the transistors.

In an embodiment, the masking element may attenuate at least one of:

- the infrared light pattern;

- the infrared flood light; incident on the second area, particularly by blocking the respective light.

In an embodiment, the first area may be an enclosed area, particularly a fully enclosed area, wherein the second area is an enclosing area, particularly a fully enclosing area, particularly wherein the second area is enclosing the first area, more particularly wherein the second area corresponds to the outer area of the at least one partially transparent continuous area.

In an embodiment, the contiguous area of the display may be associated with a first pixel density value, particularly corresponding to the at least one partially transparent continuous area, and a further area of the display is associated with a second pixel density value, wherein the first pixel density value is lower than the second pixel density value, particularly wherein the transmission of light through the contiguous area is higher compared to the transmission through the further area.

In an embodiment, the first pixel density value may be equal or below 450 PPI, preferably between 300 to 440 PPI, more preferably between 350 to 450 PPI.

In an embodiment, the first pixel density value may be constant over the entire contiguous area with a maximum deviation thereof of 20 %, or preferably 10 %. In an embodiment, the second pixel density value may be between 400 to 500 PPI, preferably between 450 to 500 PPI.

In an embodiment, the display may comprise at least one of: a display panel, particularly comprising a plurality of pixels and/or a plurality of transistors; a glass, specifically a cover glass, particularly configured for covering the display panel.

In an embodiment, the display panel may be or may comprise at least one organic light-emitting diode (OLED) display and/or at least one quantum-dot light emitting diode (QLED) display.

In an embodiment, the pattern illumination source may comprise at least one pattern projector configured for generating the infrared light pattern.

In an embodiment, the pattern illumination source, such as the pattern projector, may comprise at least one least one vertical cavity surface-emitting laser (VCSEL), preferably a plurality of VCSELs.

In an embodiment, the pattern illumination source may comprise at least one optical element configured for increasing a number of spots, wherein the at least one optical element comprises at least one diffractive optical element (DOE) and/or at least one metasurface element.

In an embodiment, the flood illumination source may comprise at least one light emitting diode (LED) and/or at least one VCSEL, preferably a plurality of VCSELs.

In an embodiment, the display device may be configured for authenticating a user of the display device to perform at least one operation on the device that requires authentication, wherein the display device comprises at least one authentication unit configured for performing at least one authentication process of a user using the flood image and the pattern image.

In an embodiment, the authentication unit may be configured for using a facial recognition authentication process operating on the flood image, the pattern image and/or extracted material data, particularly derived from the pattern image.

In an embodiment, a method for authenticating a user of a display device according to any one of the preceding device Embodiments to perform at least one operation on the display device that requires authentication is disclosed, the method may comprise: a. generating at least one pattern image by using at least one image generation unit of the display device, wherein the pattern image shows the user while the user is being illuminated with at least one infrared light pattern generated by at least one pattern illumination source of the display device, b. generating at least one flood image by using the image generation unit of the display device, wherein the flood image shows the user while the user is being illuminated with infrared flood light generated by at least one pattern illumination source of the display device, c. providing an item of identification information on the user based on the flood image, particularly by using at least one authentication unit of the device, d. providing an item of material information based on the at least one pattern image, particularly by using the authentication unit; and e. allowing the user to perform at least one operation on the device that requires authentication based on the item of identification information and item of material information.

In an embodiment, for providing the item of identification information, the method may comprise using a facial recognition authentication process operating on the flood image, the pattern image and/or extracted material data.

In an embodiment, providing an item of identification information may comprise matching the flood image with a template.

In an embodiment, the method may be computer-implemented.

In an embodiment, a computer program is disclosed comprising instructions which, when the program is executed by the display device according to any one of the preceding Embodiments referring to a device, may cause the display device to perform the method according to any one of the preceding embodiments referring to a method.

In an embodiment, a computer-readable storage medium is disclosed comprising instructions which, when the instructions are executed by the display device according to any one of the preceding Embodiments referring to a display device, may cause the display device to perform the method according to any one of the preceding embodiments referring to a method.

In an embodiment, a non-transient computer-readable medium including instructions is disclosed that, when executed by one or more processors, may cause the one or more processors to perform the method according to any one of the preceding embodiments referring to a method.

Brief description of the figures

Further optional details and features of the invention are evident from the description of preferred exemplary embodiments which follows in conjunction with the dependent claims. In this context, the particular features may be implemented in an isolated fashion or in combination with other features. The invention is not restricted to the exemplary embodiments. The exemplary embodiments are shown schematically in the figures. Identical reference numerals in the individual figures refer to identical elements or elements with identical function, or elements which correspond to one another with regard to their functions.

Specifically, in the figures:

Figure 1 shows an exemplary display device according to the present invention; and

Figure 2 shows an exemplary display device not comprising a masking element;

Figure 3a shows an exemplary radiation profile of the infrared light pattern shaped by the masking element;

Figure 3b shows an exemplary radiation profile of the infrared flood light shaped by the masking element;

Figure 4 shows an exemplary masking element; and

Figure 5 shows an exemplary method for authenticating a user of the display device.

Detailed description of the embodiments:

Figure 1 shows an exemplary display device 100 that is comprising at least one pattern illumination source 112 configured for emitting an infrared light pattern 116 and at least one flood illumination source 114 configured for emitting infrared flood light 118. The flood illumination source 114 is not depicted in Figure 1 since it may be arranged behind the pattern illumination source 112 in the paper plane.

The pattern illumination source 112 may comprise at least one pattern projector configured for generating the infrared light pattern 116. The pattern illumination source 112, such as the pattern projector, may comprise at least one least one vertical cavity surface-emitting laser (VCSEL), preferably a plurality of VCSELs. The pattern illumination source 112 may comprise at least one optical element configured for increasing a number of spots, wherein the at least one optical element comprises at least one diffractive optical element (DOE) and/or at least one metasurface element. The flood illumination source 114 may comprise at least one light emitting diode (LED) and/or at least one VCSEL, preferably a plurality of VCSELs, particularly for emitting infrared flood light 118.

The exemplary display device 100 is further comprising at least one image generation unit 150 configured for generating at least one pattern image while the pattern illumination source 112 is emitting the infrared light pattern 116 and configured for generating at least one flood image while the flood illumination source 114 is emitting infrared flood light 118. The exemplary display device 100 is further comprising at least one masking element 130 configured for covering at least one contiguous area 141 around the flood illumination source 114 and/or the pattern illumination source 112. The masking element 130 may be covered at least partially by a display 140 comprised by the exemplary display device 100. The masking element 130 may be arranged between the display 140 and at least one of the pattern illumination source 112, the image generation unit 150, the flood illumination source 114 or a combination thereof. The masking element 130 may block a portion of the infrared light pattern 116 and/or a portion of the infrared flood light 118 and may comprise at least one aperture 132 (depicted exemplarily in Figure 4).

The masking element 130 may be in contact with at least one of: the pattern illumination source 112 and/or the flood illumination source 114. The masking element 130 may be in contact with at least a part of a display covering at least one of: the pattern illumination source 112 and/or the flood illumination source 114. The masking element 130 may be associated with a transmittance, in particular a hemispherical transmittance, below 50 %, preferably below 25 %, most preferably below 5 %.

As discussed above, the exemplary display device 100 is further comprising at least one display

140 configured for displaying content, wherein the display 140 covers at least partially the pattern illumination source 112, the flood illumination source 114, the masking element 130 and/or the image generation unit 150.

The display 140 may comprise a display panel 142, particularly comprising a plurality of pixels 164 and/or a plurality of transistors 166 (exemplarily depicted in Figure 3a). Alternatively or in addition, the display 140 may comprise a glass 144, specifically a cover glass, particularly configured for covering the display panel 142.

The display 140 may be at least partially transparent in at least one continuous area 141 covering the pattern illumination source 112, the flood illumination source 114 and/or the image generation unit 150. Consequently, the infrared light pattern 116 incident on the continuous area

141 may traverse the display while being illuminated from the pattern illumination source 112; and/or the infrared flood light 118 incident on the continuous areas 141 may traverse the display 140 while being illuminated from the flood illumination source 114; and/or user light, generated by the infrared light pattern 116 and/or the infrared flood light 118 incident on a user, incident on the continuous area 141 traverses the display 140 for impinging on the image generation unit 150.

The contiguous area 141 of the display 140 may be associated with a first pixel density value, particularly corresponding to the at least one partially transparent continuous area 141 , and a further area 143 of the display may be associated with a second pixel density value, wherein the first pixel density value may be lower than the second pixel density value, particularly wherein the transmission of light through the contiguous area is higher compared to the transmission through the further area 143. The first pixel density value may be equal or below 450 PPI, preferably between 300 to 440 PPI, more preferably between 350 to 450 PPI. The first pixel density value may be constant over the entire contiguous area 141 with a maximum deviation thereof of 20 %, or preferably 10 %. The second pixel density value may be between 400 to 500 PPI, preferably between 450 to 500 PPI.

The display panel may be or may comprise at least one organic light-emitting diode (OLED) display and/or at least one quantum-dot light emitting diode (QLED) display.

The display device 100 may be configured for authenticating a user of the display device 100 to perform at least one operation on the device that requires authentication. Particularly for this purpose, the display device 100 may comprise at least one authentication unit 160 configured for performing at least one authentication process of a user using the flood image and the pattern image. The authentication unit 160 may be configured for using a facial recognition authentication process operating on the flood image and/or the pattern image, particularly received from the image generation unit 150 by a data connection 163, and/or extracted material data, particularly derived from the pattern image.

Figure 2 illustrates a display 140, a pattern illumination source 112 and an image generation unit 150 in a typical arrangement of a display device 100 not comprising a masking element 130. As may be derived from Figure 2, a portion of light of the infrared light pattern 116 (indicated by the arrows) is internally reflected in a glass 144, specifically a cover glass, of the display device 100.

As may be derived from Figure 3a, the radiation profile of the infrared light pattern 116 may be shaped by the masking element 130 in a manner that an internal reflection of the infrared light pattern 116 in the display 140, particularly in a glass 144, specifically a cover glass, comprised by the display 140, may be decreased. The infrared light pattern 116 may be indicated by the dash-dotted line. The masking element 130 blocks a portion of the infrared light pattern 116, whereby the radiation profile of the infrared light pattern 116 may be shaped. Only a portion of the infrared light pattern 116 may be allowed to pass the masking element 130 through an aperture 132 of the masking element 130, which traverses the masking element 130. The traversing portion of the infrared light pattern 116 is indicated by the solid line. By shaping the infrared light pattern 116 by the masking element, an area 146 illuminated by the infrared light pattern 116 on the display 140 may be decreased, particularly when compared to a display device 100 not having a masking element 130. Alternatively or in addition, by shaping the infrared light pattern by the masking element 130, an opening angle 117 of the shaped infrared light pattern 116 incident on the display 140 may be decreased, particularly when compared to a display device 110 not having a masking element 130. Alternatively, or in addition, as may be derived from Figure 3b, the radiation profile of the infrared flood light 118 may be shaped by the masking element 130 in a manner that an internal reflection of the infrared flood light 118 in the display 140, particularly in a glass 144, specifically a cover glass, comprised by the display 140, may be decreased. The infrared flood light 118 is indicated by the dash-dotted line. The masking element 130 blocks a portion of the infrared flood light 118, whereby the radiation profile of the infrared flood light 118 may be shaped. Only a portion of the infrared flood light 118 may be allowed to pass the masking element 130 through an aperture 132 of the masking element 130, which traverses the masking element 130. The traversing portion of the infrared flood light 118 is indicated by the solid line. By shaping the infrared flood light 118 by the masking element 130, an area 147 illuminated by the infrared flood light 118 on the display may be decreased, particularly when compared to a display device 100 not having a masking element 130. Alternatively or in addition, by shaping the infrared flood light 118 by the masking element 130, an opening angle 119 of the shaped infrared flood light 118 incident on the display 140 may be decreased, particularly when compared to a display device 100 not having a masking element.

According to Figures 3a and 3b, the internal reflection may be decreased by blocking light 116, 118, particularly generated by the pattern illumination source 112 and/or the flood illumination source 114; wherein the light 116, 118 incident on the display 140 has an angle distribution showing less angles 120 with a high value in respect to a normal 148 to the surface of the display 140 due to a blocking of these angles by the masking element 130, particularly compared to a display device not having a masking element.

As may be derived from Figure 3a and/or Figure 3b, the at least partially transparent continuous area 141 of the display may comprise a first area 161 and a second area 162. The first area 161 may be associated with a first number of transistors 166 configured for controlling at least one pixel 164 and the second area 162 may be associated with a second number of transistors 166 configured for controlling at least one pixel 164, and wherein the first number of transistors 166 may be smaller than the second number of transistors 166. The transistors 166 may be driving the pixels 164. Particularly therefore, the transistors 166 may electrically connected to the pixels 164. The first number of transistors 166 and/or the second number of transistors 166 may refer to a density of the transistors. The masking element 130 may decrease at least one of: the infrared light patternl 16; the infrared flood light 118; incident on the second area 162, particularly by blocking the respective light 116, 118. The first area 161 may be an enclosed area, particularly a fully enclosed area, wherein the second area 162 may be an enclosing area, particularly a fully enclosing area, particularly wherein the second area 162 may be enclosing the first area 161 , more particularly wherein the second area 162 may corresponds to the outer area of the at least one partially transparent continuous area 141 .

According to Fig. 4, which illustrates a top view on an exemplary masking element 130, the masking element 130 may comprise a plurality of apertures 132, particularly two apertures 132. Each aperture 132 of the plurality of apertures 132 may be associated with the pattern illumination source 112, and/or the flood illumination source 114. The pattern illumination source 112, the flood illumination source 114 are arranged behind the masking element 130 in the paper plane of Figure 4. The masking element 130 may be at least one of: silicone; a metal coating; a metal plate.

Figure 5 illustrates an exemplary method 200 for authenticating a user of a display device 100 to perform at least one operation on the display device 100 that requires authentication. The method 200 is comprising: a. in step 202, generating at least one pattern image by using at least one image generation unit 150 of the display device 100, wherein the pattern image shows the user while the user is being illuminated with at least one infrared light pattern 116 generated by at least one pattern illumination source 112 of the display device 100, b. in step 204, generating at least one flood image by using the image generation unit 150 of the display device 100, wherein the flood image shows the user while the user is being illuminated with infrared flood light 118 generated by at least one pattern illumination source 112 of the display device 100, c. in step 206, providing an item of identification information on the user based on the flood image, particularly by using at least one authentication unit 160 of the device, d. in step 208, providing an item of material information based on the at least one pattern image, particularly by using the authentication unit 160; and e. in step 210, allowing the user to perform at least one operation on the display device 100 that requires authentication based on the item of identification information and item of material information.

For providing the item of identification information, particularly in step 206, the method 200 may comprises using a facial recognition authentication process operating on the flood image, the pattern image and/or extracted material data. Providing an item of identification information, particularly in step 206, may comprise matching the flood image with a template. The method 200 may be computer-implemented.

List of reference numbers

100 display device

112 pattern illumination source

114 flood illumination source

116 infrared light pattern

117 opening angle

118 infrared flood light

119 opening angle

120 angle in respect to a normal of the display

130 masking element

132 aperture

140 display

141 continuous area

142 display panel

143 further area

144 glass

146 area illuminated by the infrared light pattern on the display

147 area illuminated by the infrared flood light on the display

148 normal to the surface of the display

150 image generation unit

152 field of view

154 area viewed by the image generation unit on the display

156 opening angle

160 authentication unit

161 first area of the continuous area

162 second area of the continuous area

163 data connection

164 pixel

166 transistor

200 method for authenticating a user of a display device

202 generating at least one pattern image

204 generating at least one flood image

206 providing an item of identification information

208 providing an item of material information

210 allowing the user to perform at least one operation

Claims

Claims

1 . A display device (100) comprising: at least one pattern illumination source (112) configured for emitting an infrared light pattern (116), at least one flood illumination source (114) configured for emitting infrared flood light (118), at least one image generation unit (150) configured for generating at least one pattern image while the pattern illumination source (112) is emitting the infrared light pattern (116) and configured for generating at least one flood image while the flood illumination source (114) is emitting infrared flood light (118), at least one masking element (130) configured for covering at least one contiguous area around the flood illumination source (114) and/or the pattern illumination source (112), at least one display (140) configured for displaying content, wherein the display (140) covers at least partially the pattern illumination source (112), the flood illumination source (114), the masking element (130) and/or the image generation unit (150).

2. The display device (100) according to the preceding claim, wherein the masking element (130) is in contact with at least one of: the pattern illumination source (112), the flood illumination source (114).

3. The display device (100) according to any one of the preceding claims, wherein the masking element (130) is in contact with at least a part of a display covering at least one of: the pattern illumination source (112), the flood illumination source (114).

4. The display device (100) according to any one of the preceding claims, the masking element (130) is associated with a transmittance, in particular a hemispherical transmittance, below 50 %, preferably below 25 %, most preferably below 5 %.

5. The display device (100) according to any one of the preceding claims, wherein the masking element (130) blocks a portion of the infrared light pattern (116) and/or a portion of the infrared flood light (118) and comprises at least one aperture (132).

6. The display device (100) according to any one of the preceding claims, wherein a radiation profile of the infrared light pattern (116) is shaped by the masking element (130) in a manner that an internal reflection of the infrared light pattern (116) in the display (140) is decreased.

7. The display device (100) according to the preceding claim, wherein, by shaping the infrared light pattern (116) by the masking element (130), an area (146) illuminated by the infrared light pattern (116) on the display (140) and/or an opening angle (117) of the infrared light pattern (116) incident on the display (140) is decreased when compared to a display device (100) not having a masking element (130).

8. The display device (100) according to any one of two preceding claims, wherein the internal reflection is decreased by blocking light incident on the display (140) generated by the pattern illumination source (112); wherein light incident on the display (140) has an angle distribution showing less angles with a high value in respect to a normal to the surface of the display (140) due to a blocking by the masking element (130) compared to a display device (100) not having a masking element (130).

9. The display device (100) according to any one of the preceding claims, wherein a radiation profile of the infrared flood light (118) is shaped by the masking element (130) in a manner that an internal reflection of the infrared flood light (118) in the display (140) is decreased.

10. The display device (100) according to any the preceding claim, wherein, by shaping the infrared flood light (118) by the masking element (130), an area (147) illuminated by the infrared flood light (118) on the display (140) and/or an opening angle (119) of the infrared flood light (118) incident on the display (140) is decreased when compared to a display device (100) not having a masking element (130).

11 . The display device (100) according to any one of two preceding claims, wherein the internal reflection is decreased by blocking light incident on the display (140) generated by the flood illumination source (114); wherein the light incident on the display (140) has an angle distribution showing less angles with a high value in respect to a normal to the surface of the display (140) due to a blocking by the masking element (130) compared to a display device (100) not having a masking element (130).

12. The device according to any one of the preceding claims, wherein the display (140) is at least partially transparent in at least one continuous area (141) covering the pattern illumination source (112), the flood illumination source (114) and/or the image generation unit (150), wherein the at least partially transparent continuous area (141) comprises a first area (161) and a second area (162), wherein the first area (161) is associated with a first density of transistors (166) configured for controlling at least one pixel (164) and the second area (162) is associated with a second density of transistors (166) configured for controlling at least one pixel (164), and wherein the first density of transistors (166) is smaller than the second density of transistors (166).

13. The display device (100) according to any one of the preceding claims, wherein the display device (100) is configured for authenticating a user of the display device (100) to perform at least one operation on the display device (110) that requires authentication, wherein the display device (100) comprises at least one authentication unit (160) configured for performing at least one authentication process of the user using the flood image and the pattern image.

14. A method for authenticating a user of a display device (100) according to any one of the preceding device claims to perform at least one operation on the display device (100) that requires authentication, the method comprising: a. generating at least one pattern image by using at least one image generation unit (150) of the display (140) device (100), wherein the pattern image shows the user while the user is being illuminated with at least one infrared light pattern (116) generated by at least one pattern illumination source (112) of the display (140) device (100), b. generating at least one flood image by using the image generation unit (150) of the display (140) device (100), wherein the flood image shows the user while the user is being illuminated with infrared flood light (118) generated by at least one pattern illumination source (112) of the display (140) device (100), c. providing an item of identification information on the user based on the flood image, particularly by using at least one authentication unit of the device, d. providing an item of material information based on the at least one pattern image, particularly by using the authentication unit; and e. allowing the user to perform at least one operation on the display device (100) that requires authentication based on the item of identification information and item of material information.

15. The method according to the preceding claim, wherein, for providing the item of identification information, the method comprises using a facial recognition authentication process operating on the flood image, the pattern image and/or extracted material data.

16. A computer program comprising instructions which, when the program is executed by the display device (100) according to any one of the preceding claims referring to a device, cause the display device (100) to perform the method according to any one of the preceding claims referring to a method.

17. A computer-readable storage medium comprising instructions which, when the instructions are executed by the display device (100) according to any one of the preceding claims referring to a display (140) device (100), cause the display device (100) to perform the method according to any one of the preceding claims referring to a method.

18. A non-transient computer-readable medium including instructions that, when executed by one or more processors, cause the one or more processors to perform the method according to any one of the preceding claims referring to a method.