Method for operating data glasses and data glasses

Abstract

The invention relates to a method (100) for operating data glasses (50), wherein the method (100) comprises the following steps: - Providing data glasses (50) (110) operable in a projection mode and in a detection mode, comprising a projection device (24), a detection device (7), a pivotable optical deflection device (11), an optical deflection element (10) and a control unit (25); - operating the data glasses (50) in the detection mode to detect a relative eye position of the user wearing the data glasses (50) with respect to the data glasses (50) (120); and - Operating the data glasses (50) in the projection mode to display image information in the field of view of the user (130) wearing the data glasses (50). The invention further relates to data glasses (50).

Description

[0001] The invention relates to a method for operating data glasses. The invention also relates to data glasses. State of the art

[0002] Smart glasses and methods for their operation are known from the prior art. Smart glasses can be configured, for example, to project image information into the field of vision of a wearer of the smart glasses using a projection device. Depending on the design of the smart glasses, a projection area of ​​the smart glasses can be transparent, allowing the projected image content to be overlaid on the real environment visible in the wearer's field of vision. To adapt and optimize the displayed image information for the wearer, smart glasses can be equipped with a detection function for detecting the wearer's eye position or gaze direction.

[0003] WO 2021 / 049740 A1 describes a device and a method for determining an eye accommodation distance for a head-mounted display with adjustable focal length. The device comprises an interferometer for generating frequency-modulated laser beams and receiving interferometric signals, a signal processing unit for generating a signal spectrum based on the interferometric signals, and a coordinate determination unit for determining coordinates of reflective surfaces of an eye of a wearer of the display. The device further comprises a reconstruction unit for generating an intraocular structure model based on the determined coordinates and a unit for determining the eye accommodation distance based on the intraocular structure model. Disclosure of the invention

[0004] According to the features of independent claim 1, a method for operating data glasses is proposed, the method comprising the following steps: - Provision of data glasses operable in a projection mode and in a detection mode, comprising ◯ a projection device with a first light source for generating a visible light beam; ◯ a detection device with a second light source for generating an infrared light beam and with a light receiving unit for detecting reflected and / or scattered infrared light signals; ◯ a pivotable optical deflection device for deflecting the generated visible and infrared light rays onto a lens of the data glasses; ◯ an optical deflection element arranged on the lens for deflecting the deflected visible and infrared light rays onto an eye of a user wearing the data glasses; and ◯ a control unit for controlling and evaluating the signals of the projection device and the detection device; - Operating the data glasses in the detection mode to detect a relative eye position of the user wearing the data glasses in relation to the data glasses by ◯ generating an infrared light beam by means of the detection device and directing the infrared light beam onto the user's eye via the pivotable optical deflection device and the optical deflection element, wherein the pivotable optical deflection device is pivoted such that the infrared light beam is deflected at successively different deflection angles and a serial optical scanning of the eye takes place; ◯ detecting infrared light signals at the light receiving unit while the infrared light beam is deflected at successively different deflection angles; and ◯ Evaluating the infrared light signals detected at the light receiving unit to determine a distance of the eye to the optical deflection element or the detection device based on the evaluated infrared light signals; and - Operating the data glasses in projection mode to display image information in the field of vision of the user wearing the data glasses by ◯ Generating a visible light beam by means of the projection device and directing the visible light beam onto the user's eye via the pivotable optical deflection device and the optical deflection element.

[0005] The proposed method makes it possible to operate smart glasses with a compact design either in a projection mode for displaying image information or in a detection mode for detecting the user's relative eye position. Due to the shared use of optical components of the smart glasses, such as the pivotable optical deflection device and the optical deflection element, in both projection and detection modes, the structural complexity of the smart glasses can be significantly reduced compared to known smart glasses with projection and detection functions. The simplified design can result in corresponding cost, space, and weight savings, thus increasing the cost-effectiveness and wearing comfort of the smart glasses.Furthermore, in the detection mode of the smart glasses, components of the projection system, such as the pivoting optical deflection device, can be used to detect the eye position and thus be efficiently utilized, while other components of the projection system are being prepared for the projection, for example, or moved. The proposed method makes it possible to determine the user's eye position relative to the smart glasses, for example, prior to a projection or between projected images.

[0006] In this context, data glasses are defined as a wearable display device that is worn in front of a user's eyes and can display image information in the user's field of vision. The term can also include so-called smart glasses and complex headsets with additional functions, such as acoustic ones. The data glasses can be configured for cross-reality applications such as virtual reality, augmented reality, or mixed reality.

[0007] According to the proposed features, the data glasses have a projection device with a first light source for generating a visible light beam. The first light source can therefore generate light in a wavelength range perceivable by the human eye. The first light source can, in particular, be a laser light source. The first light source can, for example, be an RGB color laser module with which red, green, and blue laser light beams can be generated. For the sake of simplicity, the term light beam is understood here not only to mean individual light beams, but also light beam bundles and light beam fields, which can be generated, for example, by optical bundling or expansion using corresponding optical components. The projection device can be configured to generate at least one visible light beam for reproducing image information in the user's field of vision.For this purpose, the visible light beam can be directed sequentially into different areas of the user's field of vision to create the impression of a two-dimensional image projection. The visible light beam is deflected multiple times via the pivoting optical deflection device and the optical deflection element of the data glasses, directing it onto the user's eye in such a way that visually perceptible image information is generated in the user's field of vision.

[0008] According to the proposed features, the data glasses have a detection device with a second light source for generating an infrared light beam and with a light receiving unit for detecting reflected and / or scattered infrared light signals. The second light source can therefore generate light in an infrared wavelength range that cannot be detected by the human eye. The second light source can, in particular, be a laser light source. The second light source can, for example, be an IR laser. By means of the infrared light beam and the infrared light signals of the infrared light beam reflected and / or scattered by the user's eye, it is possible to obtain information about the eye by optical scanning, in particular to determine a position of the eye, for example, an ocular surface, relative to the detection device.This makes it possible, for example, to measure eye distance or eye position. This makes it possible, for example, to determine the orientation of a data glasses' eyeglass coordinate system relative to the user's eye coordinate system. To obtain at least an approximate two-dimensional or spatial impression of the eye or an eye area, the infrared light beam can be directed sequentially to different eye regions. The infrared light beam is deflected multiple times via the pivoting optical deflection device and the optical deflection element of the data glasses, directing it onto the user's eye in such a way that optical scanning of the eye is possible using the infrared light beam.

[0009] Due to the sequential deflection of the visible and infrared light beams, the optical projection and detection processes described above can be viewed as serial projection and scanning, thus distinguishing them from simultaneous exposure by multiple light sources. This enables a simple and compact design and economical operation of the data glasses.

[0010] According to the proposed features, the data glasses have a pivotable optical deflection device for deflecting the generated visible and infrared light beams onto a lens of the data glasses. Such a pivotable optical deflection device can be an optical component movable about at least one pivot axis and configured to change the direction of a light beam, for example, a mechanically actuated mirror. Serial projection and scanning of the eye is possible by means of the pivotable optical deflection device, since the visible and infrared light beams can be deflected sequentially for further deflection into different areas of the optical deflection element.

[0011] According to the proposed features, the data glasses have an optical deflection element arranged on the lens for deflecting the deflected visible and infrared light rays onto an eye of a user wearing the data glasses. Such an optical deflection element can be an optical component designed to change the direction of a light beam. The optical component can be a simple optical deflection element, such as a mechanical mirror, or a complex optical deflection element, which can, for example, have different deflection functions along the optical deflection element and / or different deflection functions depending on the wavelength of the incident light beam. The optical deflection element can, for example, be a diffractive optical element that uses diffraction effects on an optical grating to deflect the light rays.According to an advantageous embodiment, the optical deflection element can be designed as a holographic optical element. Holographic optical elements can be used to implement very precise deflection functions that can be varied spatially or wavelength-related. At the same time, due to its transparent properties, a holographic optical element can be advantageously used as an optical deflection element in a translucent lens of data glasses.

[0012] The data glasses may also include additional optical components and / or optoelectronic components for generating, directing, and transforming visible and infrared light rays, which are not discussed in detail for reasons of clarity. The processor-based control unit of the data glasses, for example, for controlling and evaluating the signals from the projection device and the detection device, may be signal-connected to the projection device, the detection device, and other components of the data glasses, such as the pivotable optical deflection device and a 2D deflection unit (explained below), and may, for example, control the first and second light sources and detect and evaluate infrared light signals at the light receiving unit.

[0013] The data glasses can, in particular, be configured to be operated in a time-shifted manner either in the projection mode or in the detection mode, so that the generated visible and infrared light rays do not influence each other and the pivotable optical deflection device is pivoted accordingly either to scan the eye or to project image information. Accordingly, serial operation of the data glasses in projection and detection mode can be advantageous. This does not preclude, in particular, the data glasses being configured to switch between the projection mode and the detection mode in a very short time, so that, for example, short projection preparation times, such as a movement of optical components, can be used for optically scanning the eye in detection mode.A change between the projection mode and the acquisition mode can be carried out in terms of control technology based on predefined criteria, for example when the data glasses are put into operation or at predefined time intervals, and / or user-initiated.

[0014] According to one embodiment, the data glasses can further be operated in a tracking mode and the method can comprise the following further step: - Operating the data glasses in the tracking mode to detect a pupil position of the eye of the user wearing the data glasses by ◯ Generating an infrared tracking light beam and directing the infrared tracking light beam to the user's eye via the pivotable optical deflection device and the optical deflection element; ◯ detecting infrared tracking light signals at a tracking light receiving unit while the infrared tracking light beam is deflected at successively different deflection angles; and ◯ Evaluation of the infrared tracking light signals detected at the tracking light receiving unit to determine the pupil position of the eye of the user wearing the data glasses based on the evaluated infrared tracking light signals.

[0015] Such a tracking mode enables tracking of the visible light beam in projection mode to adapt the projection to the detected pupil position of the user's eye. In other words, when the user moves their eyes, the cone of visible light can be shifted such that colored light, and thus image content, continues to fall into the pupil, allowing an image to be written on the retina. In particular, the detection device can be configured to generate the infrared tracking light beam and to detect the infrared tracking light signals. For example, the second light source can be configured to generate the infrared tracking light beam, and the light receiving unit can correspond to the tracking light receiving unit. Furthermore, the control unit can be configured to evaluate the infrared tracking light signals and to determine the pupil position of the eye based thereon.The detection device and the control unit can be configured to selectively detect the pupil position of the eye of the user wearing the data glasses in tracking mode and / or to detect the relative eye position of the user with respect to the data glasses in detection mode. This enables combined detection of eye position and pupil position by means of the detection device, so that the detection device has a multiple function. Furthermore, the pivotable optical deflection device and the optical deflection element can be used for the projection mode, the detection mode, and the tracking mode and can therefore be used multiple times. Depending on the selected embodiment and correspondingly designed operating method, the data glasses can be operated in tracking mode, for example, simultaneously, with a temporal overlap, or with a temporal offset to the projection mode of the data glasses.In principle, for example, for simultaneous operation in projection and tracking mode according to alternative embodiments, it is not excluded that the data glasses have a tracking device separate from the projection device and the detection device with an associated third light source and an associated tracking light receiving unit in order to be able to implement the tracking function independently of the projection device and the detection device.

[0016] According to one embodiment, the detection device can be designed as a laser feedback interferometry sensor. A laser feedback interferometry sensor, also abbreviated to LFI sensor, is based on an interferometric measurement method using a laser. The laser emits light from a laser cavity, in particular infrared light, which strikes a surface with a reflectivity at an angle. The light is scattered back by the surface, so that it re-enters the laser cavity. In the laser cavity, the backscattered light interferes with the locally oscillating field of the laser. This leads to a modulation of the laser power, which can be detected either by a photodiode integrated into a back reflector of the laser cavity or by measuring the electrical voltage of the laser.If the detection device is designed as an LFI sensor, the second light source and the light receiving unit can advantageously be combined in a single structural unit, thus contributing to an even more compact design of the data glasses. Accordingly, the method steps of generating an infrared light beam using the detection device and detecting infrared light signals at the light receiving unit using the LFI sensor can be implemented. Furthermore, the LFI sensor can optionally also be used for a tracking mode of the data glasses to detect the pupil position of the eye of the user wearing the data glasses, allowing the LFI sensor to perform multiple functions and further increasing the functional density of the data glasses.

[0017] According to a further development, the LFI sensor can be operated in the detection mode of the data glasses using a modulation signal. This enables precise determination and differentiation of distances between partially transparent components of the data glasses and the user's eye relative to the detection device and / or relative to each other. For example, a triangular modulation signal can be used to cyclically shift the wavelength of the laser of the LFI sensor. The infrared light signals detected at the light receiving unit can be evaluated based on the modulation signal using a wavelength-dependent spectrum, which enables precise determination of distances between the partially transparent components of the data glasses and the eye.

[0018] The determination of the distance to the eye and its surface speed can be done, for example, with known laser parameters using a beat frequency f0 and a Doppler frequency f d take place: f0=2Lextλ2dλdIdIdt|Lext=const. fd=2vextcos(γ)λ|λ=const.

[0019] With known wavelength λ, wavelength shift dλ dt and cos(γ), the surface velocity and the distance to the eye can be determined.

[0020] According to one embodiment, first position coordinates along the optical deflection element can be determined based on the successively different deflection angles of the pivotable optical deflection device and distance coordinates can be determined based on the distance of the eye from the optical deflection element, determined by means of the detected infrared light signals, and assigned to the first position coordinates. This enables systematic scanning and enables simple further processing of the distance coordinates depending on the position coordinates.From the first position coordinates, which can, for example, represent simplified values ​​of an x-axis formed along the optical deflection element, and from the distance coordinates, which can, for example, represent simplified values ​​of a z-axis extending perpendicular to the optical deflection element as a distance measure, a two-dimensional point cloud can be derived for evaluation purposes, with which, for example, a line-shaped height profile of the eye region can be obtained.

[0021] According to one embodiment, the pivotable optical deflection device can be pivotable about at least two different pivot axes. The pivot axes can, for example, be two or more mutually perpendicular spatial axes. The pivot axes can, in particular, be actuated independently of one another. By pivoting the pivotable optical deflection device about at least two different pivot axes, a multidimensional deflection of visible and infrared light beams is possible. This allows, for example, spatially more complex scanning in acquisition mode or tracking mode and spatially more complex projections in projection mode to be realized.

[0022] According to a further development, two-dimensional first and second position coordinates along the optical deflection element can be determined based on the successively different deflection angles of the optical deflection device pivotable about at least two different pivot axes, and distance coordinates can be determined based on the distance of the eye from the optical deflection element, determined in each case using the detected infrared light signals, and assigned to the first and second position coordinates. This enables multi-dimensional scanning of the eye in detection mode and / or in tracking mode, thus achieving more precise eye detection. For example, the pivotable optical deflection device can be pivoted about one of the at least two different pivot axes during each pivoting process, such that the first position coordinate is maintained and the second position coordinate is varied, or vice versa.Accordingly, a two-dimensional scan of the eye is possible, which together with the assigned distance coordinates results in a three-dimensional point cloud, so that a planar height profile is available over the scanned two-dimensional plane.

[0023] According to one embodiment, a curved contour line can be determined using the first position coordinates and the distance coordinates, or a spherical contour surface can be determined using the first and second position coordinates and the distance coordinates. A reconstruction of the user's eye is achieved by fitting a circular shape to the curved contour line or by fitting a spherical shape to the spherical contour surface. Accordingly, depending on a one- or two-dimensional scan of the user's eye, which can be performed, for example, depending on the pivoting mobility of the pivotable optical deflection device about one or more pivot axes, an eye model can be generated by fitting a circular or spherical shape to the determined contour line or contour surface.Compared to conventional, often very complex and computationally intensive 3D eye models, the proposed embodiment provides a very simple method for obtaining relative distance and position information of the eye with respect to the smart glasses. Furthermore, the obtained reconstruction data can be used additionally for pupil detection in a tracking mode of the smart glasses.

[0024] According to one embodiment, a deviation of the detected eye position from a predetermined eye position can be determined depending on the detected relative eye position of the user wearing the data glasses with respect to the data glasses. A predetermined eye position can, for example, refer to an eye position optimized for the projection mode, which can be predetermined by control technology, for example by stored pattern coordinates or eye models that are comparable, for example, with the reconstruction of the eye in terms of geometric properties for deviations. By comparing the detected relative eye position with a predetermined eye position, it is possible, for example, to evaluate or classify the determined deviation, for example with regard to a small deviation or a large deviation.By evaluating or classifying the deviation according to predefined criteria, it can be easily processed further and, for example, depending on the classification result, different control processes can be triggered, such as an information output to the user or a computational compensation measure.

[0025] According to a further development, depending on the determined deviation, compensation for the deviation can be carried out when displaying image information in the field of view of the user wearing the data glasses in projection mode. In other words, the deviation can be compensated for by a computational adjustment of the control of the projection device and the pivoting optical deflection device. As a result, if the data glasses do not fit optimally, the user is not affected by the deviation of their actual eye position from a predetermined eye position, thus increasing user comfort. Compensation for the deviation can be carried out, for example, if the deviation can be classified as a minor deviation. As a result, the data glasses can, within certain limits, adapt the projected image information to the detected deviation, despite their compact design.

[0026] According to a further development, depending on the detected deviation, a request can be issued to the user to correct the fit of the data glasses. This can offer active support in adjusting the fit of the data glasses without the need for separate measuring systems or trained specialists for fit correction. By actively changing the fit of the glasses by requesting a fit correction, the projection and display function of the data glasses can be optimized in a simple and convenient way. The request can, for example, be triggered via a control system and transmitted to a signal-connected end device, such as the user's smartphone. In headset combinations, an acoustic request is also conceivable. Visual information output via the projection function of the data glasses is also not excluded.The request can contain instructions with varying levels of detail, for example, in addition to a simple request to correct the seat position, it can also include specific direction or distance information to further detail the seat correction. A request to correct the seat position can be issued, for example, if the deviation of the detected eye position from a predetermined eye position can be classified as a significant deviation. This allows the deviation to be reduced or eliminated easily, particularly without significant control-related computational effort.

[0027] The invention also relates to data glasses comprising - a projection device with a first light source for generating a visible light beam; - a detection device with a second light source for generating an infrared light beam and with a light receiving unit for detecting reflected and / or scattered infrared light signals; - a pivotable optical deflection device for deflecting the generated visible and infrared light rays onto a lens of the data glasses; - an optical deflection element arranged on the lens for deflecting the deflected visible and infrared light rays onto an eye of a user wearing the data glasses; and - a control unit for controlling and signal evaluating the projection device and the detection device;wherein the data glasses are operable in a projection mode and in a detection mode and are configured to be operated according to the method described above.

[0028] The proposed smart glasses also achieve the aforementioned advantages of a compact design combined with a simple implementation of a projection mode for displaying image information and a detection mode for detecting the user's relative eye position. Due to the shared usability of the smart glasses' optical components, such as the pivoting optical deflection device and the optical deflection element, in both projection and detection modes, the structural complexity of the smart glasses can be significantly reduced compared to known smart glasses with projection and detection functions. The simplified design can result in corresponding cost, space, and weight savings, thus increasing the cost-effectiveness and comfort of the smart glasses.Furthermore, in the detection mode of the data glasses, components of the projection system such as the pivoting optical deflection device can also be used to detect the eye position and can therefore be utilized efficiently.

[0029] According to one embodiment, the data glasses can further be operated in a tracking mode. Such a tracking mode enables tracking of the visible light beam in projection mode to adapt the projection to the detected pupil position of the user's eye. In particular, the above-described detection device can be configured to generate an infrared tracking light beam and to detect infrared tracking light signals. Accordingly, the control unit can be configured to evaluate the infrared tracking light signals and, based thereon, to determine the pupil position of the eye. The detection device and the control unit can be configured to optionally detect the pupil position of the eye of the user wearing the data glasses in tracking mode and / or to detect the relative eye position of the user with respect to the data glasses in detection mode.This enables combined detection of eye position and pupil position using the detection device, thus giving the detection device a multifunctional function. Furthermore, the pivotable optical deflection device can be used for the projection mode, the detection mode, and the tracking mode. In principle, according to alternative embodiments, it is not excluded that the data glasses have a tracking device separate from the projection device and the detection device, with a third light source and / or with a separate tracking light receiving unit, in order to implement the tracking function with increased flexibility and independence.

[0030] According to one embodiment, the data glasses can have a laser feedback interferometry sensor. This allows the second light source and the light receiving unit to be advantageously combined in a single structural unit, so that this embodiment contributes to an even more compact design of the data glasses. The laser feedback interferometry sensor, abbreviated to LFI sensor, can optionally also be used for a tracking mode of the data glasses to detect a pupil position of the eye of the user wearing the data glasses, so that the LFI sensor can have multiple functions and the functional density of the data glasses is further increased. The detection device embodied as an LFI sensor can, for example, be arranged together with the projection device in a common structural unit, e.g., designed as a laser module.Alternatively, it is conceivable to provide the detection device, designed as an LFI sensor, separately from the projection device and, for example, to couple it upstream of the pivotable optical deflection device using a suitable coupling structure. According to alternative embodiments, it is also not excluded to use, for example, an IR laser as a second light source with a separate photodetector or another optical detection unit as the light receiving unit. For example, a photodetector such as a photodiode or a CCD element can be used as the light receiving unit and can be arranged, for example, in a spectacle lens or in a frame of the data glasses.

[0031] According to one embodiment, the optical deflection element can be designed as a diffractive optical element with different deflection functions for the visible light beam and the infrared light beam. For example, a deflection function of the optical deflection element for the visible light beam can be configured such that the visible light beam is deflected convergently, while a deflection function of the optical deflection element for the infrared light beam can be configured such that the infrared light beam is deflected less convergently, essentially parallel, or divergently. By specifically designing the deflection functions in this way depending on the wavelength range of the deflected light beam, it is possible to precisely match the deflection functions to the respective function of the light beam.For example, convergent deflection of the visible light beam can be associated with high projection quality and image sharpness, while less convergent to divergent illumination of the eye regions enables efficient optical scanning of the eye. According to a further development, the optical deflection element can be designed as a holographic optical element. Holographic optical elements can be used to implement very precise and spatially varying deflection functions. At the same time, due to its transparent properties, a holographic optical element can be advantageously used as an optical deflection element in a translucent lens of data glasses.

[0032] According to one embodiment, the data glasses can have a 2D deflection unit arranged between the first light source and / or the second light source and the pivotable optical deflection device. In other words, the 2D deflection unit can be arranged in a beam path of the first and / or second light source in the direction of the pivotable optical deflection device. With such a 2D deflection unit, for example, it is possible to generate a light beam field from a single light beam or light beam bundle. In other words, the light emitted by the first and / or second light source can be expanded two-dimensionally by means of the 2D deflection unit. Such a two-dimensional expansion can advantageously be used to generate image information in projection mode and for surface scanning of the eye in the detection and / or tracking mode of the data glasses.The 2D deflection unit enables efficient operation of the data glasses with a compact design, providing advantageous optical coverage of the user's field of vision and eye region, as well as complex optical functions. The 2D deflection unit can be implemented, for example, by a two-dimensional microelectromechanical mirror, two one-dimensional microelectromechanical mirrors, a spatial light modulator, a rotating prism, a mechanically actuated mirror, or another optical component for implementing two-dimensional beam shaping and / or beam deflection.

[0033] According to one embodiment, a projection lens can be arranged between the pivotable optical deflection device and the optical deflection element. This allows the field of view of the projection to be increased and image errors to be corrected, particularly in the projection mode of the data glasses. The projection lens can advantageously be designed as a segmented lens.

[0034] In general, in the context of this application, the words "a / an," unless expressly defined otherwise, are not to be understood as a number, but as an indefinite article with the literal meaning of "at least one." In particular, it is not excluded, for example, that the data glasses are configured to project image information and to detect an eye position with respect to both eyes of the user. The above description can therefore be applied analogously to an application involving both eyes, wherein, in particular, at least one projection device, one detection device, one pivotable optical deflection device, and one optical deflection element can be provided for each eye.

[0035] The invention permits various embodiments and is explained in more detail below using an exemplary embodiment with the accompanying drawings. They show schematically: Fig. 1 - a schematic diagram of a projection device and a detection device of data glasses; Fig. 2 - a schematic diagram of a detection device designed as an LFI sensor; Fig. 3 - an exemplary spectral representation of infrared light signals detectable by means of a modulated LFI sensor for determining a relative eye position of a user of the data glasses; Fig. 4 - a schematic diagram of the detection device in a detection mode of the data glasses; Fig. 5 - an exemplary evaluation diagram with distance coordinates determined by means of the detection device, which are assigned to first position coordinates; Fig. 6 - a schematic flow diagram of a method for operating the data glasses; and Fig. 7 - a schematic diagram of the data glasses.

[0036] Fig. 1 shows schematically in a principle representation a projection device 24 and a detection device 7 of a Fig. 7. The data glasses 50 can be operated in a projection mode for displaying image information in the field of view of the user wearing the data glasses 50 and in a detection mode for detecting a relative eye position of the user wearing the data glasses 50 with respect to the data glasses 50. The projection device 24 has a first light source 2, 3, 4, which is designed as a color laser system arranged in a laser module 6 with a first laser 2 for generating visible light in a red wavelength range, with a second laser 3 for generating visible light in a green wavelength range, and with a third laser 4 for generating visible light in a blue wavelength range.According to the exemplary embodiment shown, the laser module 6 further contains an IR laser configured to generate an infrared light beam. It can optionally be used as a second light source 1 in combination with a separate light receiving unit 12, e.g., configured as a photodiode and integrated into a spectacle lens 51 or a spectacle frame of the data glasses 50, as a detection device for the data glasses 50, or it can be used to generate an infrared tracking light beam in combination with the light receiving unit 12 for a tracking mode of the data glasses 50, which will be explained below. Alternatively, the second light source 1 can also be configured as an LFI sensor and thus have an integrated light receiving unit 12.Depending on the application and embodiment, it is conceivable to combine the infrared light beam with the visible light beams of the first light source 2, 3, 4 to form an RGB / IR beam via a beam combining unit, which may, for example, comprise one or more prisms, waveguides, and / or light couplers. The projection device 24 is particularly configured to generate a visible light beam 18, 19 using the first light source 2, 3, 4.

[0037] In Fig. 1 further shows a detection device 7, which according to the embodiment shown is designed as an LFI sensor. In Fig. 2 schematically illustrates such a detection device 7 configured as an LFI sensor. The LFI sensor has a second light source 1 configured as an IR laser for generating an infrared light beam 22. The LFI sensor further comprises a light receiving unit 12 for detecting reflected and / or scattered infrared light signals 16, 17. In the laser cavity of the LFI sensor, the infrared light signals 16, 17 interfere with the locally oscillating field of the IR laser. This leads to a modulation of the laser power, which can be detected either by the photodiode shown as the light receiving unit 12 or by measuring the electrical voltage of the IR laser. By designing the detection device 7 as an LFI sensor, the second light source 1 and the light receiving unit 12 can be combined compactly in one optical unit. As shown in Fig. 1, the generated infrared light beam 22 of the detection device 7 is coupled into an optical path of the projection device 24 via a coupling structure 5. Furthermore, reflected and / or scattered infrared light signals 16, 17 can be coupled out of the optical path back to the detection device 7 via the coupling structure 5, so that the infrared light signals 16, 17 can be detected by the detection device 7.

[0038] The Fig. 1, it can further be seen that an optical deflection device 11, which can be pivoted in a pivoting direction 15, is arranged in the optical path of the visible light beams 18, 19 and the infrared light beams 22, 23. The pivotable optical deflection device 11 can, for example, be designed as a mechanically actuated mirror. By means of the pivotable optical deflection device 11, the visible light beams 18, 19 and the infrared light beams 22, 23 are directed to a Fig. 4 and Fig. 7 of the data glasses 50. An optical deflection element 10 is arranged on the spectacle lens 51, which serves to deflect the deflected visible light rays 18, 19 and the deflected infrared light rays 22, 23 onto an eye 14 of a user wearing the data glasses 50. The optical deflection element 10 can be designed in particular as a diffractive optical element, in particular as a holographic optical element, with different deflection functions for the visible light beam 18, 19 and the infrared light beam 22, 23. As the Fig. 1, for example, the visible light beam 18, 19 can be deflected convergently so that a light cone is formed which runs in the direction of the eye 14 and the visible light beams 18, 19 can collect in the pupil of the eye 14, while the infrared light beams 22, 23 are deflected essentially in parallel according to the embodiment shown and thus allow a wider illumination of the eye 14.

[0039] In Fig. 1 further shows that the data glasses 50 have a 2D deflection unit 8, which is arranged between the laser module 6 and the coupling structure 5 and the pivotable optical deflection unit 11. The 2D deflection unit 8 enables two-dimensional deflection to generate a light beam field from the incident visible and infrared light beams 18, 19, 22, 23. The 2D deflection unit 8 can be implemented, for example, by a two-dimensional microelectromechanical mirror. The two-dimensional beam field is then deflected by the pivotable optical deflection device 11, as described above, at successively different deflection angles in the direction of the optical deflection element 10. As shown in the exemplary embodiment shown, a projection lens 9, in particular designed as a segment lens, can be arranged between the pivotable optical deflection unit 11 and the optical deflection element 10.This allows the field of view of the projection to be increased and image errors to be corrected, especially in projection mode. As is also the case with the . Fig. 7, the data glasses 50 also have a control unit 25 for controlling and signal evaluation of the projection device 24 and the detection device 7 as well as other components of the data glasses 50 such as the pivotable optical deflection device 11.

[0040] If the data glasses 50 are operated in the detection mode for detecting a relative eye position of the user wearing the data glasses 50 in relation to the data glasses 50, the detection device 7 designed as an LFI sensor is used as shown in Fig. 1, an infrared light beam 22, 23 is generated and directed onto the user's eye 14 via the pivotable optical deflection device 11 and the optical deflection element 10. The infrared light beam 22 is reflected and / or scattered at the user's eye 14, so that infrared light signals 16, 17 are generated, which can be detected, for example, by an additional photodiode as the light receiving unit 12 and / or by the light receiving unit 12 of the LFI sensor. During the generation of the infrared light beam 22, 23, the pivotable optical deflection device 11 is pivoted, so that the infrared light beam is deflected at successively different deflection angles and, as shown in Fig. 1, impinges on different regions of the eye 14, so that a serial optical scanning of the eye 14 is enabled by means of the pivotable optical deflection device 11. The infrared light signals 16, 17 which can be detected in this way are evaluated by the control unit 25 and used to determine, for example, a Fig. 2 and Fig. 3 schematically shown distance d between the LFI sensor and the eye 14 is used.

[0041] If the data glasses 50 are operated in projection mode to display image information in the field of view of the user wearing the data glasses 50, a visible light beam 18, 19 is generated by the projection device 24, and the visible light beam 18, 19 is directed onto the user's eye 14 via the pivotable optical deflection device 11 and the optical deflection element 10. In particular, the pivotable optical deflection device 11 is pivoted during the projection process, so that the visible light beam 18, 19 is guided over the eye 14 according to the image information to be displayed and, if applicable, depending on a pupil position 20, 21.

[0042] By jointly using the pivotable optical deflection device 11 and the optical deflection element 10 for the detection and projection mode with serial scanning and projection steps, the functions of projection and detection of the eye position can be efficiently implemented with a compact design of the data glasses 50.

[0043] Again Fig. 1, the data glasses 50 according to the embodiment shown can be operated in a tracking mode for detecting a pupil position 20, 21 of the eye 14. For this purpose, the detection device 7 designed as an LFI sensor can also be used as a tracking device. Alternatively, for example, the IR laser arranged in the laser module 6 can be used as a second light source 1 in combination with a separate light receiving unit 12 that can be used as a tracking light receiving unit. If the data glasses 50 are operated in the tracking mode, which can take place, for example, when using the IR laser with the separate light receiving unit 12, even during an active projection mode or offset in time to the projection mode by means of the detection device 7 designed as an LFI sensor, the Fig. 1 can also be used as tracking light beams. The resulting infrared light signals 16, 17 can be detected as tracking light signals by the light receiving unit 12 or the detection device 7 and used to determine a current pupil position 20, 21 of the eye 14. By detecting the current pupil position 20, 21 of the eye 14, tracking of the visible light beam 18, 19 is possible to adapt the projection to the detected pupil position 20, 21. Fig. 1 illustrates such an adaptation by detecting the differing pupil positions 20, 21 using the infrared light beams 22, 23 directed onto the eye 14 at different deflection angles of the pivotable optical deflection device 11 and the correspondingly differently backscattered infrared light signals 16, 17, as well as a corresponding adjustment of the deflection angles for the visible light beams 18, 19 to adapt the projection region to the detected pupil position 20, 21. In particular, the same deflection angle at which the pupil position 20, 21 of the eye 14 is detected in the detection mode can be set for the deflection of the visible light beam 18, 19 in the projection mode.

[0044] Fig. 3 shows an exemplary spectral representation of infrared light signals 16, 17 that can be detected by means of a modulated LFI sensor for determining a relative eye position of a user of the data glasses 50. The Fig. The arrangement shown in Figure 2, schematically simplified without the coupling structure 5, the pivotable optical deflection device 11, and the optical deflection element 10, can be operated using, for example, a triangular modulation signal on the LFI sensor, so that a cyclic shift of the wavelength of the IR laser is achievable. The infrared light signals 16, 17 that can be detected in this way can be assigned to different distances d and correspondingly to the different partially transparent components of the optical path that backscatter the infrared light beams 22, 23. Thus, the points marked in the upper part of the spectral representation can, for example, be assigned to the following components and objects: Fig. 1 lens system (not shown in detail) (1), 2D deflection unit 8 (2), pivotable optical deflection unit 11 (3), optical deflection element 10 (4) and eye 14 (5). The partial reflection of the eye 14 can therefore be the furthest distance d from which the infrared light is scattered back, so that the distance d between the optical deflection element 10, the pivotable optical deflection unit 11 and the eye 14 can be determined. The thus determined distance d to the eye 14 of the user can, as will be explained in more detail below with reference to the Fig. 4 and Fig. 5, for different positions along an x-axis of the deflection element 10 and assigned to the respective x-position, so that a two-dimensional point cloud is obtained.

[0045] In Fig. Figure 4 shows a further schematic diagram of the detection device 7 in a detection mode of the data glasses 50. The detection device 7 generates infrared light beams 22, 23, which are deflected by the pivotable optical deflection device 11 at different deflection angles onto the optical deflection element 10 and from there redirected to the eye 14.

[0046] Due to the different deflection angles, the infrared light beams 22, 23 strike the surface of the optical deflection element 10 at different positions along an x-axis and then travel different distances corresponding to a distance d between the optical deflection element 10 and the curved surface of the eye 14. The positions along the x-axis of the optical deflection element 10 can be recorded as first position coordinates x. The distance d of the eye 14 determined at the first position coordinates x using the infrared light signals 16, 17 can be recorded as distance coordinates z along a z-axis running perpendicular to the x-axis in the direction of the eye 14 and assigned to the respective first position coordinates x.This enables systematic scanning and, by assigning the distance coordinates z to the position coordinates x, a two-dimensional point cloud can be derived, which can be used, for example, as in . Fig. 5 a linear height profile of at least one eye region R1, R2 of the eye 14 can be obtained.

[0047] In Fig. 5, distance coordinates z are plotted against first position coordinates x. This allows, for example, curved contour lines K to be identified in a first eye region R1 and in a second eye region R2, in which the infrared light strikes the sclera of the eye 14. By fitting a circular shape into the curved contour line, a reconstruction of the user's eye 14 can be performed. The data points can be used, for example, to calculate the general circle equation x2+z2=−a2−b2+2ax+2bz−r2 according to a, b and r and thus to determine the diameter and the position of the circular section of the sclera for the linear height profile. According to a further development, it is conceivable to transfer the contour detection described here two-dimensionally into a higher dimensional plane by a pivoting mobility of the pivotable optical deflection device 11 about at least two pivot axes in order to enable a multi-dimensional scanning of the eye 14 with a planar height profile and a spherical contour surface for a corresponding fitting of a spherical shape for the spatial reconstruction of the eye 14. For example, in a planar scanning of the eye 14, the sphere can be defined using the equation ax2+by2+cz2=r2 be fitted with respect to the parameters a, b, c and r, for example by a least-square method.

[0048] What is not illustrated in detail is that, depending on the detected relative eye position of the user, a deviation of the detected eye position from a predetermined eye position can be determined. Based on the detected deviation, for example, a computational compensation of the deviation can be performed in a projection mode of the data glasses 50 when generating image information and deflecting the visible light rays 18, 19, or the user can be prompted to correct their sitting position.

[0049] Fig. 6 shows a schematic, simplified flow diagram of a method 100 for operating the data glasses 50. In step 110, a pair of data glasses 50 operable in a projection mode and in a detection mode is provided. In step 120, the data glasses 50 are operated in the detection mode to detect a relative eye position of the user wearing the data glasses 50 with respect to the data glasses 50. In step 130, the data glasses 50 are operated in the projection mode to display image information in the field of view of the user wearing the data glasses 50. The order of steps 120 and 130 is not fixed to the specified order, so that operation of the data glasses 50 in the projection mode can also be followed by operation of the data glasses 50 in the detection mode.In particular, the projection mode and the detection mode can be repeated one after the other, so that during operation of the data glasses 50, a projection and a detection of the user's eye position are alternately possible. Optionally, the data glasses 50 can also be configured in a . Fig. 6 tracking mode not shown in detail.

[0050] In Fig.Figure 7 shows a simplified schematic representation of a pair of data glasses 50. The data glasses 50 have a lens 51 and a temple 52. According to the illustrated embodiment, the projection device 24, the detection device 7, the pivotable optical deflection device 11, and the control unit 25 of the data glasses 50 are arranged in the temple, by means of which a projection and detection of the eye position, as well as optionally a tracking of the pupil position 20, 21 of the user, can be enabled.Furthermore, the optical deflection element 10 is arranged in the spectacle lens 51. This element is implemented, for example, as a diffractive optical element, in particular as a holographic optical element, and serves to deflect the visible light rays 18, 19 and the infrared light rays 22, 23 generated by the projection device 24 and the detection device 7, which are variably deflected onto the deflection element 10 by means of the pivotable optical deflection device 11, onto the user's eye 14. With the data glasses 50, a simple implementation of the projection mode and the detection mode is possible with a compact design, while efficiently reusing the optical components of the data glasses 50. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] WO 2021 / 049740 A1

[0003]

Claims

[1] Method (100) for operating data glasses (50), the method (100) comprising the following steps: - Providing a pair of data glasses (50) (110) operable in a projection mode and in a detection mode, comprising ◯ a projection device (24) with a first light source (2, 3, 4) for generating a visible light beam (18, 19); ◯ a detection device (7) with a second light source (1) for generating an infrared light beam (22, 23) and with a light receiving unit (12) for detecting reflected and / or scattered infrared light signals (16, 17); ◯ a pivotable optical deflection device (11) for deflecting the generated visible and infrared light rays (18, 19, 22, 23) onto a spectacle lens (51) of the data glasses (50); ◯ an optical deflection element (10) arranged on the spectacle lens (51) for deflecting the deflected visible and infrared light rays (18, 19, 22, 23) onto an eye (14) of a user wearing the data glasses (50); and ◯ a control unit (25) for controlling and signal evaluation of the projection device (24) and the detection device (7); - Operating the data glasses (50) in the detection mode to detect a relative eye position of the user wearing the data glasses (50) with respect to the data glasses (50) (120) by ◯ generating an infrared light beam (22, 23) by means of the detection device (7) and directing the infrared light beam (22, 23) onto the eye (14) of the user via the pivotable optical deflection device (11) and the optical deflection element (10), wherein the pivotable optical deflection device (11) is pivoted such that the infrared light beam (22, 23) is deflected at successively different deflection angles and a serial optical scanning of the eye (14) takes place; ◯ detecting infrared light signals (16, 17) at the light receiving unit (12) while the infrared light beam (22, 23) is deflected at the successively different deflection angles; and ◯ Evaluating the infrared light signals (16, 17) detected at the light receiving unit (12) to determine a distance (d) of the eye (14) to the optical deflection element (10) or the detection device (7) on the basis of the evaluated infrared light signals (16, 17); and - Operating the data glasses (50) in the projection mode to display image information in the field of view of the user (130) wearing the data glasses (50) by ◯ Generating a visible light beam (18, 19) by means of the projection device (24) and directing the visible light beam (18, 19) onto the eye (14) of the user via the pivotable optical deflection device (11) and the optical deflection element (10). [2] The method (100) according to claim 1, wherein the data glasses (50) are further operable in a tracking mode and wherein the method (100) comprises the further step of: - Operating the data glasses (50) in the tracking mode to detect a pupil position (20, 21) of the eye (14) of the user wearing the data glasses (50) by ◯ generating an infrared tracking light beam (22, 23) and directing the infrared tracking light beam (22, 23) onto the eye (14) of the user via the pivotable optical deflection device (11) and the optical deflection element (10); ◯ detecting infrared tracking light signals (16, 17) at a tracking light receiving unit (12) while the infrared tracking light beam (22, 23) is deflected at successively different deflection angles; and ◯ Evaluating the infrared tracking light signals (16, 17) detected at the tracking light receiving unit (12) to determine the pupil position (20, 21) of the eye (14) of the user wearing the data glasses (50) based on the evaluated infrared tracking light signals (16, 17). [3] Method (100) according to claim 1 or 2, wherein the detection device (7) is designed as a laser feedback interferometry sensor. [4] The method (100) of claim 3, wherein the LFI sensor is operated in the detection mode of the data glasses (50) using a modulation signal. [5] Method (100) according to one of the preceding claims, wherein first position coordinates (x) along the optical deflection element (10) are determined on the basis of the successively different deflection angles of the pivotable optical deflection device (11) and distance coordinates (z) are determined on the basis of the distance (d) of the eye (14) to the optical deflection element (10) determined in each case by means of the detected infrared light signals (16, 17) and are assigned to the first position coordinates (x). [6] Method (100) according to one of the preceding claims, wherein the pivotable optical deflection device (11) is pivotable about at least two different pivot axes. [7] Method (100) according to claim 6, wherein two-dimensional first and second position coordinates along the optical deflection element (10) are determined on the basis of the successively different deflection angles of the optical deflection device (11) pivotable about at least two different pivot axes, and distance coordinates are determined on the basis of the distance (d) of the eye (14) to the optical deflection element (10), which distance coordinates are assigned to the first and second position coordinates, respectively, by means of the detected infrared light signals (16, 17). [8] Method (100) according to one of claims 5 to 7, wherein a curved contour line (K) is determined by means of the first position coordinates (x) and the distance coordinates (z) or a spherical contour surface is determined by means of the first and second position coordinates and the distance coordinates, wherein a reconstruction of the eye (14) of the user is carried out by fitting a circular shape into the curved contour line or by fitting a spherical shape into the spherical contour surface. [9] Method (100) according to one of the preceding claims, wherein a deviation of the detected eye position from a predetermined eye position is determined as a function of the detected relative eye position of the user wearing the data glasses (50) with respect to the data glasses (50). [10] Method (100) according to claim 9, wherein, depending on the determined deviation, a compensation of the deviation is carried out in the display of image information in the field of view of the user wearing the data glasses (50) in the projection mode of the data glasses (50). [11] Method (100) according to claim 9 or 10, wherein, depending on the determined deviation, a request is issued to the user to carry out a seat correction of the data glasses (50). [12] Data glasses (50) having - a projection device (24) with a first light source (2, 3, 4) for generating a visible light beam (18, 19); - a detection device (7) with a second light source (1) for generating an infrared light beam (22, 23) and with a light receiving unit (12) for detecting reflected and / or scattered infrared light signals (16, 17); - a pivotable optical deflection device (11) for deflecting the generated visible and infrared light rays (18, 19, 22, 23) onto a spectacle lens (51) of the data glasses (50); - an optical deflection element (10) arranged on the spectacle lens (51) for deflecting the deflected visible and infrared light rays (18, 19, 22, 23) onto an eye (14) of a user wearing the data glasses (50); and - a control unit (25) for controlling and signal evaluating the projection device (24) and the detection device (7); wherein the data glasses (50) are operable in a projection mode and in a detection mode and are configured to be operated according to the method (100) according to one of claims 1 to 11. [13] Data glasses (50) according to claim 12, wherein the data glasses (50) are further operable in a tracking mode. [14] Data glasses (50) according to claim 12 or 13, wherein the data glasses (50) comprise a laser feedback interferometry sensor. [15] Data glasses (50) according to one of claims 12 to 14, wherein the optical deflection element (10) is designed as a diffractive optical element with different deflection functions for the visible light beam (18, 19) and the infrared light beam (22, 23). [16] Data glasses (50) according to one of claims 12 to 15, wherein the data glasses (50) have a 2D deflection unit (8) arranged between the first light source (2, 3, 4) and / or the second light source (1) and the pivotable optical deflection device (11). [17] Data glasses (50) according to one of claims 12 to 16, wherein a projection lens (9) is arranged between the pivotable optical deflection device (11) and the optical deflection element (10).

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