Projection assembly and method for illuminating a plurality of virtual pixels

Abstract

The invention relates to a projection assembly (1) for illuminating a plurality of virtual pixels (2) which produce a first individual image during a first time frame. The projection assembly (1) comprises a laser assembly (4) having a plurality of laser light sources (5a, 5b, 5c) which are designed to emit laser light (L1, L2, L3) of substantially the same wavelength via a plurality of emission points arranged at a defined distance to one another. The projection assembly (1) additionally comprises a deflecting module (6) which is designed to deflect laser light (L1, L2, L3) generated by the laser light sources (5a, 5b, 5c) onto the plurality of virtual pixels (2) one after the other and, within a first sub-time frame during the first time frame, laser light (L1) of a first laser light source (5a) onto a first pixel (2a) and laser light (L2) of a second laser light source (5b) onto a second pixel (2b). The projection assembly (1) also comprises a control element which is designed to actuate the plurality of laser light sources (5a, 5b, 5c) and / or the deflecting module (6) such that during the first time frame, a third pixel (2c) is illuminated with laser light (L2) of the second laser light source (5b) within a second sub-time frame and the third pixel (2c) is illuminated with laser light (L1) of the first laser light source (5s) within a later third sub-time frame.

Description

[0001]2023PF01221 - 1 - PROJECTION ARRANGEMENT AND METHOD FOR ILLUMINATION OF A PLURALITY OF VIRTUAL PIXELS The present application claims priority from German patent application No. 10 2023 133 019.5 of November 27, 2023, the disclosure content of which is hereby incorporated into the present application by reference. The present invention relates to a projection arrangement for illuminating a plurality of virtual pixels that produce a first individual image during a first time window, as well as to a method for illuminating a plurality of virtual pixels. BACKGROUND 5 LBS (Laser Beam Scanning) devices for NTE (Near-to-Eye) glasses, also called data glasses, are becoming increasingly popular and are therefore constantly being developed further. Compared to Liquid Crystal on Silicon (LCoS) LED systems and Digital Light Processing (DLP) LED systems, LBS0 systems have the advantage ofTo put it simply, only those pixels of a single frame that are illuminated (painted) within the time required to display the single image contribute to energy consumption. This statement is incomplete in that laser light sources in LBS systems also consume energy in their non-emitting state. However, compared to LCoS LED and DLP LED systems, where the entire image area must be constantly illuminated to display a single image, the energy consumption of an LBS system is lower. Furthermore, the luminance that a laser light source in an LBS system can deliver is a major advantage over LED systems. By adjusting the supply current applied to the laser light source and / or by adjusting the illumination time of a pixel, the luminance of the pixel can be increased almost indefinitely compared to LED systems.without having to enlarge the optical interface. The brightness dynamics of a laser light source are also high compared to an LED or an OLED. 2023PF01221 - 2 - However, to achieve high image resolution and image brightness, LBS systems are heavily dependent on the interaction between the laser power and a deflection module for scanning the pixels of an individual image. Currently, a limiting factor is the frequency of the deflection module, e.g., a MEMS mirror, by means of which the individual pixels of each individual image can be scanned and illuminated. Furthermore, it has been determined that, despite existing energy savings in an LBS system compared to other known systems, especially in the area of ​​compact data glasses, even further energy reductions are desirable.since the space available for accumulators to provide energy is very limited. 5 In summary, there is a need to provide a system, in particular a system for projecting at least one individual image, which is compact, provides high image brightness, provides a high dynamic range in image brightness, provides high image resolution, and at the same time has the lowest possible energy consumption. SUMMARY OF THE INVENTION 5 This need is met by the subject matter of the independent patent claims. Further developments and embodiments of the proposed principle are specified in the subclaims. In known LBS systems, each individual laser light source must cover the entire dynamic brightness range in order toto be able to image different brightness levels. This often leads to low wall-plug efficiency (WPE) when low brightness is required and to a lack of optical power when high brightness is required. Furthermore, the energy consumption of such laser light sources during standby mode is very high. This means that the laser light source is operated just below the laser threshold during pixel scanning if the emission of laser light and thus illumination of a pixel is to be suppressed, but a rapid ramp-up for illumination of a subsequent pixel is to be enabled. In simplified terms, the laser threshold is higher the higher the maximum optical power of a laser light source. The inventor now proposes a projection arrangement and a method for operating such a projection arrangement.The projection arrangement, in particular an LBS system, uses several laser light sources per wavelength or light color in combination with a deflection module designed to simultaneously illuminate several virtual pixels of an individual image on a projection surface with the light from the multiple laser light sources. This makes it possible to achieve an increased resolution of the individual image at a given raster frequency of the deflection module. Furthermore, the inventor proposes using smaller laser light sources or laser light sources with shorter laser ridges compared to known systems.which, at the expense of light output, but in favor of a lower required threshold current for use in an LBS system, exhibit a lower average power consumption. This is due to the fact that the current required to operate the laser light sources just below the laser threshold is significantly reduced, and the laser light sources thus consume significantly less energy in a so-called standby mode. In order to increase the image brightness, which is reduced due to the reduced light output, the inventor proposes illuminating the virtual pixels requiring increased brightness several times within a single image in order to suggest to the human eye a correspondingly high overall brightness of the pixel. Although this means that, at a given scanning frequency of the deflection module, a previously achieved increase in resolution must be partially reduced again,However, a situational decision can be made as to whether higher image brightness with reduced resolution or lower image brightness with increased resolution is desired. The core of the projection arrangement according to the invention lies in the use of an illumination scheme (painting scheme), in which a virtual pixel of an individual image can be illuminated several times during the duration of the display of the individual image. Theoretically, this can also be achieved by a higher scanning frequency of the deflection module, but since the scanning frequency of known deflection modules is currently a limiting factor in an LBS system,A multiple illumination of a virtual pixel within a single image requires a correspondingly designed deflection module in combination with more than one laser light source per wavelength / color. Using such a projection arrangement, at least some of the following advantages can be achieved: 0 ▪ compact form factor (e.g.: < 0.7mm³); ▪ high image brightness & high dynamic range (e.g.: indoor night mode = 300 nt – 500 nt, outdoor beach mode = 10,000 nt), where 1 nt = 1 cd / m²; ▪ low energy consumption (e.g.: 100 mW / eye of a user);5 ▪ high or appropriately high image resolution; ▪ the display of the single image is independent of the distance between the projection arrangement and the projection surface, so that even a non-flat projection surface (eye) can be illuminated. 0 In addition, it is possibleto respond to different framework conditions depending on the situation with the projection arrangement according to the invention. For example, the projection arrangement can permanently switch between different operating modes and / or generate mixed operating modes in order to optimally adapt the projected image mode to the situation. Possible modes can be, for example: 2023PF01221 - 5 - (1) High-resolution mode. For example, all laser light sources are operated in parallel to display the individual image with as many illuminated virtual pixels as possible. In this mode, the number of illuminated pixels per individual image is maximized (resolution), while the brightness of the individual illuminated virtual pixels of the individual image is reduced. (2) High-brightness mode. For example, all laser light sources are operated in parallel to illuminate fewer virtual pixels of an individual image multiple times during the duration of displaying an individual image.i.e., to create a single image with a reduced resolution but an increased perceived brightness.5 In this mode, the image resolution (illuminated pixels / single image) is reduced, while either the absolute brightness of the single image is increased,and / or a high dynamic range in brightness can be realized. 0 (3) Low brightness mode The low brightness mode can be implemented with different resolutions depending on requirements. In low brightness mode, the laser light sources can be operated with low current or, in particular, the illuminated virtual pixels are not illuminated multiple times per individual image. With relatively small laser light sources, such a mode can be comparatively efficient and energy-saving. 0 (4) Dynamic image resolution The image resolution of each individual image can be adapted to the situation. For example, if the projection arrangement includes eye tracking of a user of the projection arrangement, it is possible to support foveated rendering, which can further reduce the overall energy consumption of the projection arrangement. Foveated rendering is, in particular, a rendering techniquein which an eye tracker integrated into virtual reality glasses is used to reduce the rendering effort by significantly reducing the image quality / resolution in the peripheral vision area (outside the area viewed by the fovea). 5 (5) Dynamic brightness control The brightness of each individual image can be adjusted depending on the situation. The overlap of augmented reality (AR) with the real world in an AR environment requires a high dynamic brightness range to avoid glare on the one hand and to make AR information visible even on bright surfaces on the other. Accordingly, it may be possible toto adjust the brightness of the individual image or the brightness of successive individual images depending on the situational brightness of the environment. According to a first aspect, a projection arrangement is provided for illuminating a plurality of virtual pixels. The plurality of illuminated pixels results in a first individual image during a first time window. The number of illuminated virtual pixels by means of which the individual image is displayed or which result in the individual image, together with the size of the displayed individual image, are a measure of the image resolution, also called resolution for short. An individual image displayed using more illuminated virtual pixels has a higher resolution than an individual image of the same size displayed with fewer illuminated virtual pixels. In order to achieve a higher resolution,A single image must be represented by a larger number of illuminated pixels or by means of a larger number of illuminated pixels while maintaining the same size. The term "frame" is to be understood as an image that is displayed for a defined period of time to represent the single image. This period is also referred to below as the time window during which the single image is displayed or generated. In the field of film and video technology, where several individual images are displayed one after the other to represent moving images, the period for displaying the single image is determined by the frame rate (more precisely, frame rate). 5 The frame rate refers in particular to the number of individual images that are recorded or reproduced per period of time and is usually expressed in fps (frames per second).less frequently FPS (frames per second) or Hz (Hertz). The human eye perceives successive images as a moving (but not necessarily smooth) scene at approximately 14 to 16 frames per second (individually different). Current frame rates, however, are 24 Hz (in many movies), 48 Hz (in elaborately produced new movies and in 3D cinema), 25i / 30i Hz (in television), and 60–390 Hz (in computer games). 5 To display a single image, the projection arrangement comprises a laser arrangement with a plurality of laser light sources designed to emit laser light with essentially the same wavelength. Each laser light source is assigned an emission window or emission point.via which the laser light sources emit laser light from the laser arrangement. The emission points are arranged at a defined distance from one another. 5 In particular, the laser arrangement can be a multi-channel laser, also called a multi-ridge laser, which comprises a plurality of laser ridges formed on a common semiconductor substrate. The laser light sources or their emission windows can be arranged at a defined distance from one another, in particular at a distance of less than 30 µm or less than 10 µm. To reduce power consumption, the laser light sources can be relatively small, in particular laser light sources with a reduced laser ridge length. 5 The laser ridges can be arranged parallel and / or stacked on a semiconductor substrate. However, it is also possiblethat the laser light sources are formed by individual laser light sources 2023PF01221 - 8 - that are arranged side by side or stacked. Combinations of the above-mentioned embodiments are also possible. However, the laser arrangement can be a photonic integrated circuit (PIC) coupled to a plurality of laser light sources. The emission points are combined to a small, defined distance from one another in the waveguides of the PIC, so that the emission points can be arranged at a distance from one another, for example, in the range between 3 µm and 5 µm0. Such a configuration has the advantage that the laser light sources themselves can be spaced further apart.in order to better dissipate heat individually during operation. Furthermore, electro-optical interactions between neighboring laser light sources can be better reduced. In order to be able to illuminate the individual image or the virtual pixels of the individual image with light of more than just one wavelength / color, the projection arrangement can comprise multiple laser arrangements, wherein the laser light sources of each laser arrangement are designed to emit light of a different wavelength / color. For example, the projection arrangement can comprise three laser arrangements, wherein the laser light sources of a first laser arrangement are designed to emit red light, the laser light sources of a second laser arrangement are designed to emit green light, and the laser light sources of a third laser arrangement are designed to emit blue light. This can result in a so-called RGB projection arrangement.by means of which the virtual pixels of an individual image can be illuminated with the colors red, green, and blue, from which colors any further desired color can be mixed. Furthermore, the projection arrangement comprises a deflection module designed to deflect laser light generated by the laser light sources successively onto the plurality of pixels to be illuminated. 5 The deflection module can in particular be designed to deflect light from the laser light sources sequentially, for example, row by row and column by row, onto the virtual pixels of the individual image to be illuminated on the projection surface. For this purpose, the deflection module can, for example, be designed to be movable.For example, to redirect the light from the laser light sources to the virtual pixels of the individual image on the projection surface to be illuminated at periodic intervals within the time window for displaying the individual image. Such periodic redirection of the light from the laser light sources to the virtual pixels of the individual image on the projection surface can also be referred to as scanning the pixels or painting the pixels. For example, the redirection module can be designed to redirect a certain number of positions, also called theoretical pixels, at a defined frequency.on, for example, a projection surface or5 a projection plane. These positions or theoretical pixels can be arranged in particular in columns and rows and, in particular, equidistant from one another in the horizontal and vertical directions. The number of positions or theoretical pixels can be determined in particular by the maximum size of an image to be displayed, the maximum possible sampling frequency of the deflection module, the length of the time window for displaying an individual image, and optionally by a number of positions or theoretical pixels that the deflection module can simultaneously illuminate per scanning position. Accordingly, a theoretical pixel pitch can result because5 the deflection module scans per time window. In this regard, it should be noted that the number of illuminated pixels that result in an individual image can differ from the number of theoretical pixels. However, it is also possiblethat the number of illuminated pixels that result in a single image is identical to the number of theoretical pixels. Illumination of all theoretical pixels results in a single image with the maximum possible resolution, whereas illumination of only a portion of all theoretical pixels results in a single image with reduced resolution. 5 2023PF01221 - 10 - The time for scanning the pixels can, for example, result from the time window for displaying the single image and the number of theoretical pixels and can be referred to below in particular as a partial time window. For example, the time for scanning the pixels, i.e., a partial time window, can result from the time window for displaying the single image divided by the number of theoretical pixels. The time for scanning the pixels, i.e., a partial time window,can accordingly also result from the time window for displaying the individual image and the number of scanning positions of the deflection module, whereby the number of scanning positions can differ from the number of virtual pixels to be illuminated. For example, the time for scanning the pixels, i.e. a partial time window, can result from the time window for displaying the individual image divided by the number of scanning positions of the deflection module. The period of a partial time window is in particular a true sub-area of ​​a time window and is correspondingly shorter than the period of a time window. For example, the deflection module can comprise movable parts and be formed, for example, by one or more MEMS mirrors, which deflect the light from the laser light sources onto the virtual pixels of the individual image to be illuminated on the projection surface. For example, the deflection module can be formed by at least two mirrors arranged in series,in particular MEMS mirrors, which each move or oscillate about an axis. The mirrors can oscillate about two essentially perpendicular axes, so that one mirror scans, for example, the columns of a theoretical pixel array in sequence, and the other mirror scans the rows of the theoretical pixel array at a slower frequency. However, the reverse order is also possible. The deflection module can also be formed by one or more mirrors that oscillate simultaneously about two essentially perpendicular axes. Preferably, the mirror oscillates about both axes at a natural frequency (-> low energy consumption) so that the mirror(s) scan a pattern that deviates from a Cartesian pixel pitch, in particular so-called Lissajous figures. In both cases, a virtual pixel is then illuminated,if the geometric condition of the laser light source and mirror position allows it. Since the individual emission points of the laser array are spatially separated from one another, it is possible to illuminate a virtual pixel with light from different laser light sources. In this way, several laser light sources can be superimposed to illuminate a virtual pixel. However, it is also possible for the deflection module to be formed by or comprise one or more polygon mirrors. The polygon mirrors can rotate about two axes that are essentially perpendicular to one another, so that one polygon mirror scans, for example, the columns of a theoretical pixel array in sequence, and the other polygon mirror scans the rows of the theoretical pixel array at a slower frequency. However, it is also possible in the reverse order. It is also possiblethat the deflection module contains non-moving parts and yet still provides the desired functionality. For example, the deflection module can comprise one or more so-called optical phased arrays (OPAs). Phased array optics is a technology for controlling the phase and amplitude of light waves transmitted or reflected from a two-dimensional surface using adjustable surface elements. By dynamically controlling the optical properties of a surface at the microscopic level, it is possible to direct the direction of light rays without moving parts. This allows the production of diffractive optical elements such as dynamic virtual lenses.which, in addition to alignment, also serve for beam focusing or splitting. Real-time holograms can also be generated through dynamic phase variation. By means of such a deflection module, the light from the laser light sources can be deflected in the desired manner onto the virtual pixels of the individual image on the projection surface to be illuminated. According to the invention, the deflection module is designed to simultaneously deflect laser light from a first laser light source onto a first pixel and laser light from a second laser light source onto a second pixel during a first time window within a first partial time window, in particular during a scanning position of the movable 2023PF01221 - 12 - deflection module. During a partial time window, several virtual pixels can thus be illuminated simultaneously. In the case of a one-piece element or interconnected elements, the deflection module can be designed such thatthat at the time of a scanning position, it simultaneously deflects the light, for example, from two adjacent emission points and thus two laser light sources, to two different pixels. At a time of a subsequent scanning position, for example, after the deflection module has been moved, the deflection module can then simultaneously deflect the light from the adjacent laser light sources to two other pixels. Alternatively, in the case of several separate elements, the deflection module can be designed such thatthat at the time of a scanning position, a first element of the deflection module deflects light from a first laser light source onto a first pixel, and simultaneously a second element of the deflection module deflects light from a second laser light source onto a second pixel. At a time of a subsequent scanning position, the elements of the deflection module can then, after the movement has taken place, deflect the light from the two laser light sources onto two other pixels. Furthermore, the projection arrangement comprises a control element that is designed to control the plurality of laser light sources and / or the deflection module in such a way thatthat during the first time window, a third pixel is illuminated with laser light from the second laser light source within a second partial time window, and within a later third partial time window, the third pixel is illuminated with laser light from the first laser light source. During the time window for displaying an individual image, one or more, or all, of the virtual pixels to be illuminated can be illuminated consecutively with light from several of the laser light sources. This can increase the perceived brightness of the illuminated pixels. However, with a given scanning frequency of the deflection module, this has the consequence that not all theoretical pixels can be illuminated, and thus the resolution of the individual image must be at least partially reduced by simultaneously illuminating several pixels. 2023PF01221 - 13 - However, a situation-dependent decision can be madewhether a higher image brightness with reduced resolution or a lower image brightness with increased resolution is desired. 5 For the purposes of the description, a "first" and "second", for example a "first" partial time window and a "second" partial time window or a "first" laser light source and a "second" laser light source, refer in particular to two different areas, elements, time periods, or objects. 0 The projection arrangement can in particular be designed to illuminate the virtual pixels on a projection surface or projection plane. A projection surface can in particular be understood as a surface onto which the image to be projected is projected.5 Examples of this can be, for example, a projector by means of which an image is projected onto a wall or a screen. In the case that an image is to be generated in the eye, for example by means of data glasses, a distinction can be made, however,that an image is to be generated on a projection plane or, alternatively, an image on a projection surface. There are basically two options for generating an image in the eye. (A) Systems that work with a waveguide. Here, an image is generated on a virtual intermediate plane / projection plane. The image is then replicated multiple times in two spatial directions in the waveguide. 5 This creates an eye box. The eye box is generally the area in which the viewer's eye can perceive an image. In the case of a waveguide system, this is, for example, an area in the lens of a spectacle from which a copy of the multiple replicated image of the virtual intermediate plane falls into the eye. 0 (B) In a retinal scan, location information of the virtual pixel to be illuminated in the image to be generated is converted into angular information. In order to generate an image in the eye (on the retina), a mirror is integrated into the lens of, for example, data glasses.For example, in the form of a holographic mirror invisible to the viewer,5 the projection plane / surface can accordingly also be located directly in the eye, on the viewer's retina. 2023PF01221 - 14 - In some aspects, the projection arrangement is designed to display a second individual image during a second time window after displaying a first individual image during a first time window. The first and second individual images can in particular differ from one another, so that moving images can be generated by means of the projection arrangement, at least as perceived by the human eye. In some aspects, the projection arrangement further comprises a light-shaping optic arranged between the laser arrangement and the deflection module. The light-shaping optic is designed in particular to collimate the laser light emitted by the laser arrangement.so that essentially collimated laser light impinges on the deflection module. Essentially collimated can be understood in particular to mean that the laser light is collimated as far as possible and has a tendency toward focusing rather than toward light scattering. The light-shaping optics can be designed such that the light spot of the laser light is very small in the area of ​​the virtual pixels to be illuminated. For example, if 100% collimation is not possible, the laser light can have a focal point between the deflection module and the virtual pixels to be illuminated. In some aspects, the control element is designed to operate the plurality of laser light sources in a pulsed manner. In particular, the laser light sources can be operated in a pulsed manner within a partial time window such that they are illuminated for a maximum of 60% of the time of a partial time window.In particular, no more than 40% of a sub-time window should be operated above their laser threshold. In continuous wave (CW) mode, there is a risk of the laser light sources rolling over even at low optical output power, as they are difficult to cool down. In an operating mode with a limited laser duty cycle (e.g., 10% - 20%) and short pulse modulation (e.g., 2 ns - 5 ns), cooling between the current pulses allows for a much higher drive current.without thermal rollover occurring. In particular, the maximum optical power of a laser or laser light source is limited by rollover. This is the thermal overload of the laser due to self-heating. Laser light sources with a shorter laser ridge have a smaller cooling cross-section and therefore tend to overheat sooner. Since the rollover point of a laser is strongly influenced by the power output (self-heating) and the cooling, excessive self-heating can be counteracted when using comparatively small laser light sources by operating the laser light sources in pulsed mode. In pulsed operation with long intervals between the current pulses, the rollover point shifts to higher optical powers,so that the laser light sources can be operated below this critical optical power without overheating. The use of small laser light sources, which are also operated in pulsed mode, therefore has the advantage that the laser light sources have a relatively low laser threshold, but can be operated efficiently above the laser threshold without overheating. As a result, the laser light sources operate with a high WPE, and due to the low laser threshold, the proportion of the required threshold current to the total current required can be reduced. Accordingly, the energy consumption of the projection arrangement can be reduced. The pulsed operation of the laser light sources during the partial time windows can also have the effect that the laser light sources are only activated for a very short period of a few nanoseconds. This means that, in the case of laser light sources comprising a laser ridge,the laser ridge does not settle cleanly within this short time (the modes cannot develop perfectly). This can result in a broadening of the emission spectrum emitted by the laser light sources of up to 2 nm in pulsed operation compared to continuous wave operation, for example. 2023PF01221 - 16 - A possible difference of up to 2 nm in the laser light emitted by the laser light sources can correspondingly lead to a slightly shifted, broadened emission spectrum compared to the other laser light sources.so that a pixel illuminated multiple times by these laser light sources is illuminated with laser light with a spectral width of possibly 3 nm to 5 nm. Superimposing the light from the pulsed laser light sources can, with a minimal difference (offset) in the respective emitted laser light, lead to a spectral broadening of the total laser light emitted onto a virtual pixel, which can, for example, suppress optical artifacts in the projection arrangement. In some aspects, the plurality of laser light sources has a low threshold current limit. For example, the threshold current limit at an operating temperature of approximately 25°C for a green or red light-emitting laser light source can be less than 30 mA, in particular less than 25 mA, and less than 10 mA for a red light-emitting laser light source.in particular, at 0 is less than 6 mA. In particular, the laser light sources are designed or configured such that their threshold current is as low as possible. This is achieved, for example, by the use of comparatively short laser ridges. In this way, the required power consumption in the standby mode of the laser light sources can be reduced5 and the power consumption can be kept to a minimum. In some aspects, the control element is configured to operate laser light sources that are not intended to emit light within a partial time window below their laser threshold, in particular, however, with a current greater than 0 or just below the laser threshold. Such operation can in particular be referred to as standby mode of the laser light sources and can serve to enable the laser light source to be activated quickly,when a virtual pixel to be illuminated is to be illuminated by light from the laser light source when scanning the individual image and does not have to be fully powered up first. In addition, in standby mode, a distinction can be made as to whether the laser light sources are operated in a "standby mode" just below the laser threshold, for example, with a current of approximately 60% to 80% of the threshold current limit, or whether the laser light sources are operated in a "sleep mode" with a current of only approximately 10% to 30% of the threshold current limit. This can depend, in particular, on whether the laser light source needs to be activated in the foreseeable future to illuminate a virtual pixel or not. In particular, the control element can be designed to take into account the image information of the image to be projected, and laser light sources,which do not need to be activated for several partial time windows into a sleep mode, while shortly before laser light sources need to be activated, these laser light sources are put into standby mode so that they can be activated within the shortest possible time. This approach can also reduce the energy consumption of the projection arrangement. In some aspects, the control element and / or the deflection module is designed toDuring the first time window, a first subset of the theoretical pixels is to be illuminated multiple times with laser light from the plurality of laser light sources, and a second subset of the theoretical pixels is to be illuminated with laser light only from one of the plurality of laser light sources, or not at all. This allows, in particular, virtual pixels of an individual image to be illuminated to be more strongly illuminated than other areas, for example, to display different brightnesses of areas of the individual image during a single image. Furthermore, isolated symbols can be displayed in this way, with only pixelsthat represent the symbol can be illuminated or can be illuminated more brightly. 0 In some aspects, the plurality of virtual pixels to be illuminated are arranged in rows and columns and, in particular, are arranged equidistant from one another. In some aspects, the plurality of virtual pixels to be illuminated are arranged closer together in a first region than in an adjacent second region. In the latter case in particular, in a first region of the theoretical pixels, for example, some of the theoretical pixels can be unilluminated, whereas in a second region of the theoretical pixels, several or all of the theoretical pixels are illuminated. The illuminated virtual pixels are correspondingly further apart from one another in the first region, so that the resolution in this region is reduced, whereas in the second region they are closer together.thus, the resolution is increased. However, it is also possible that the theoretical pixels already have more densely packed regions and less densely packed regions due to the design of the deflection module, so that illumination of the theoretical pixels can lead to virtual pixels to be illuminated that are arranged at different densities to one another. In some aspects, the projection arrangement further comprises an ambient light sensor that is designed toto detect a brightness or a brightness level of the surroundings of the projection arrangement. The control element is further configured to illuminate a first subset of the theoretical pixels multiple times with laser light from the plurality of laser light sources during the first time window, depending on a sensor signal from the ambient light sensor, and to illuminate a second subset of the theoretical pixels with laser light from only one of the plurality of laser light sources. This allows, in particular, pixels of an individual image to be illuminated more strongly than other areas, for example, to display different brightnesses of areas of the individual image during an individual image. This can be advantageous, for example, in unfavorable light and shadow conditions.when areas of the projection arrangement are arranged in a brighter environment than other areas. In addition, the sensor signal of the ambient light sensor can be used to accommodate different brightness levels of the environment when switching between two individual images, so that, for example, a first individual image can be displayed brighter than a subsequent or later second individual image. 5 In some aspects, the control element and / or the deflection module is configured to illuminate each of the pixels of the theoretical pixels at most once with laser light from each of the plurality of laser light sources during a second time window. Accordingly, a dynamic resolution can be provided by means of the projection arrangement,in that more of the theoretical pixels can be illuminated for a second individual image than for the first individual image. 5 A further aspect relates to data glasses comprising a projection arrangement according to some of the aforementioned aspects. The projection arrangement is designed to project a plurality of virtual and illuminated pixels into at least one eye of a user of the data glasses. In particular, these can be AR glasses or VR glasses, for example. In some aspects, the data glasses also comprise a sensor for detecting the viewing direction of a user of the data glasses. In particular, the direction in which a user of the data glasses is looking can be checked essentially in real time. The control element and / or the deflection module can further be designed to, during the first time window and depending on a sensor signal from the sensor for detecting the viewing direction, pixels,that lie in a central area of ​​the user's line of sight multiple times with laser light from the plurality of laser light sources, and to illuminate pixels that lie in an edge area surrounding the central area with laser light from only one of the plurality of laser light sources. As a result, areas of the individual image that lie in the user's field of sight can be displayed brighter than areas of the individual image that lie in an edge area surrounding the field of sight. However, it is also possible to explicitly illuminate areas that are not in the user's direct field of sight much brighter, for example to direct the user's field of sight in this direction or to warn the user, for example. In some aspects, the control element and / or the deflection module is designed to, during the first time window and depending on a sensor signal from a sensor for detecting the line of sight, areas,that lie in a central area of ​​the user's line of sight with a higher resolution, i.e., in this area, for example, to illuminate the maximum possible theoretical pixels, and to illuminate areas that lie in an edge area surrounding the central area with a lower resolution, i.e., to illuminate a smaller number of pixels in this area than the possible theoretical ones. This allows areas of the individual image that lie in the user's field of vision to be displayed with a higher resolution than areas of the individual image that lie in an edge area surrounding the field of vision. 0 According to a further aspect, a method for illuminating a plurality of virtual pixels is proposed,wherein the plurality of pixels produce a first individual image during a first time window. The method can be carried out in particular with a projection arrangement according to some of the above aspects, so that the aspects described for the projection arrangement can also apply equally to the method. The method comprises the steps of: operating a laser arrangement with a plurality of laser light sources configured to emit light with substantially the same wavelength via a plurality of emission points arranged at a defined distance from one another, such that the laser light sources emit laser light in the direction of a deflection module; deflecting the laser light emitted onto the deflection module successively onto the plurality of virtual pixels to be illuminated, wherein the deflection module is configured such thatthat during a first time window within a first sub-time window, laser light from a first laser light source is simultaneously deflected onto a first pixel, laser light from a second laser light source onto a second pixel, and laser light from a third laser light source onto a third pixel; and controlling the plurality of laser light sources and / or the deflection module such that during the first time window, the third pixel is illuminated with laser light from the second laser light source within a second sub-time window, and within a later third sub-time window, the third pixel is illuminated with laser light from the first laser light source. In some aspects, the step of operating the plurality of laser light sources comprises pulsed operation of the plurality of laser light sources, in particular such that the laser light sources are illuminated for a maximum of 60% of the time of a sub-time window within a sub-time window.in particular, at most 40% of the time of a partial time window, above their laser threshold. 0 In some aspects, the step of operating the plurality of laser light sources comprises operating laser light sources that are not intended to emit light within a partial time window below their laser threshold. 5 In some aspects, the step of controlling the plurality of laser light sources and / or the deflection module comprises that, during the first time window, a first subset of the plurality of pixels is illuminated multiple times with laser light from the plurality of laser light sources and0 a second subset of the plurality of virtual pixels is illuminated with laser light from at most one of the plurality of laser light sources. In some aspects, the step of controlling the plurality of laser light sources and / or the deflection module comprises,5 that the plurality of virtual pixels are projected, for example, onto a projection surface or a projection plane in rows and columns, wherein the pixels are arranged in particular equidistant from one another; or that the plurality of virtual pixels are projected, for example, onto a projection surface or a projection plane in a first region with a closer distance to one another than in an adjacent second region. In some aspects, the step of controlling the plurality5 of laser light sources and / or the deflection module comprises, during a second time window, each pixel of the plurality of virtual pixels, 2023PF01221 - 22 - which result in a second individual image,is illuminated at most once with laser light from each of the plurality of laser light sources. BRIEF DESCRIPTION OF THE DRAWINGS 5 Further aspects and embodiments according to the proposed principle will become apparent with reference to the various embodiments and examples, which are described in detail in conjunction with the accompanying drawings. 0 Figure 1 shows a projection arrangement, as well as a step of a method according to the proposed principle; Figure 2 shows a projection arrangement, as well as a further 5 step of a method according to the proposed principle; Figure 3 shows a projection arrangement,and a further step of a method according to the proposed principle; Figure 4 schematically shows the illumination of a virtual pixel by means of a projection arrangement according to the proposed principle; Figure 5 schematically shows the illumination of several virtual pixels5 within a first time window by means of a projection arrangement according to the proposed principle. DETAILED DESCRIPTION The following embodiments and examples show various aspects and their combinations according to the proposed principle. The embodiments and examples are not always to scale. Likewise, various elements may be shown enlarged or reduced in size to emphasize individual aspects. It goes without saying5 that the individual aspects and features of the embodiments and examples shown in the figures can be easily combined with one another.without thereby impairing the inventive principle. Some aspects have a regular structure or shape. It should be noted that in practice, slight deviations from the ideal shape may occur without, however, contradicting the inventive idea. 5 Furthermore, the individual figures, features, and aspects are not necessarily shown in the correct size, and the proportions between the individual elements do not necessarily have to be fundamentally correct. Some aspects and features are emphasized by being shown enlarged. However, terms such as "top", "above", "bottom", "below", "larger", "smaller", and the like are correctly represented with respect to the elements in the figures. This makes it possibleto derive such relationships between the elements from the illustrations. 5 Figures 1 to 3 show a projection arrangement 1 for illuminating a plurality of virtual pixels 2 on a projection surface 3. On the projection surface 3, the illuminated virtual pixels result in a single image, which is displayed or generated, in particular, during a first time window. By way of example, only the actual virtual pixels to be illuminated are shown in the figures, and the number of theoretical pixels that could be projected by means of the arrangement 1 can also be larger. 5 In the case shown, the virtual pixels 2 are shown exemplarily on a flat projection surface 3. The pixels, however, can also lie in a virtual projection plane or intermediate plane, as can be the case, for example,when the individual image is to be projected into the eye of a user of the projection arrangement. 0 The projection arrangement 1 comprises a laser arrangement 4 with a plurality of laser light sources 5a, 5b, 5c, which are arranged at a defined distance from one another and are designed to emit laser light L1, L2, L3 with essentially the same wavelength. 5 In the illustrated case, the laser arrangement 1 is exemplarily formed by a multi-laser comprising three laser ridges 5a, 5b, 5c, each with a light exit window 2023PF01221 - 24 - located at one end of the laser ridge. The laser ridges are formed on a common semiconductor substrate and have a lateral distance of less than 10 µm from one another. 5 The projection arrangement 1 further comprises a light-shaping optics 7,which is arranged between the laser arrangement 4 and a deflection module 6 in the beam path of the laser arrangement 4. The light-shaping optics 7 is designed to shape the laser light L1, L2, L3 emitted by the laser arrangement 4 and, in particular, to substantially collimate it. The deflection module 6 is designed to deflect a laser light L1, L2, L3 generated by the laser light sources 5a, 5b, 5c successively onto the plurality of virtual pixels 2. For this purpose, the deflection module 5 is designed such that it is movable, in particular rotatable, about at least one axis, in the illustrated case about at least two axes. This is indicated in the figures by the two axes shown in dashed lines, one horizontal and one vertical, as well as by the arrows at the end of the axes. Furthermore, the deflection module 6 is designed, as shown in Figure 1,During a first time window and within a first sub-time window, simultaneously redirect laser light L1 from a first laser light source 5a to a first pixel 2a of the plurality of virtual pixels 52, laser light L2 from a second laser light source 5b to a second pixel 2b of the plurality of virtual pixels 2, and laser light L3 from a third laser light source 5c to a third pixel 2c of the plurality of virtual pixels 2, without substantially moving. In the illustrated case, this is exemplified for three laser light sources, whose light can be redirected simultaneously by the redirection module to three different pixels. However, it should be understood that this can also be done in a similar manner with more or fewer laser light sources, or that the light from all or a subset of the laser light sources can also be redirected simultaneously to the same pixel 5. Furthermore, it should be understood thatthat combinations of the aforementioned options are possible. 2023PF01221 - 25 - Furthermore, the projection arrangement 1 comprises a control element (not shown) designed to control the plurality of laser light sources 5a, 5b, 5c and / or the deflection module 6 such that, as shown in Figure 2, during the first time window, the third pixel 2c of the plurality of virtual pixels 2 is illuminated with laser light L2 from the second laser light source within a second sub-time window, and within a later third sub-time window, as shown in Figure 3, the third pixel 2c is illuminated with laser light L1 from the first laser light source 5a. Accordingly, during the first time window, the virtual pixels to be illuminated can be illuminated not only by laser light from one laser light source, but also by laser light from several laser light sources.so that the perceived brightness of these multiply illuminated virtual pixels is increased. This is particularly advantageous when using laser light sources that have lower optical power than laser light sources from known LBS systems. This allows virtual pixels to be efficiently illuminated with low luminance, for example, only with light from one laser light source, depending on requirements, while simultaneously illuminating virtual pixels with high luminance by illuminating the virtual pixel using laser light from multiple laser light sources, so that the perceived overall brightness is still high. This is summarized and illustrated by way of example in the form of graphs in Figure 4 for an exemplary pixel. In addition, Figure 4 shows the characteristic curve of the individual laser light sources.to explain the advantage of smaller laser light sources, especially when standby mode is required. 0 The laser characteristic curve has the shape of a hockey stick. From zero to the threshold value, a current I flows without any significant light emission P. Only at currents I above the threshold value does the laser ridge begin to lase (stimulated emission) and deliver up to a connected current I. f a high luminance P optAlthough the time from zero to the operating range of a laser is only a few nanoseconds, the laser must be operated just below the threshold if an instantaneous turn-on characteristic is required (NTE, frequency 0.2 GHz). This causes permanent energy consumption. In general, it can be said that the higher the maximum optical power of a laser, the higher the laser threshold. Therefore, one idea of ​​the invention is to reduce the laser threshold by reducing the size of the laser light sources and to compensate for the lost light power due to the reduced size by multiple illumination of the pixels to be illuminated. Although this does not reduce the energy consumption required to illuminate the pixel to be illuminated with the same brightness, it can significantly reduce the current consumed during standby times between pixel illuminations.The graphs on the left show the individual laser characteristics for the laser light sources shown in Figures 1 to 3. Each of these can be activated within a partial time window and redirected to a virtual pixel to illuminate it. Above the threshold value, the laser light sources can be adjusted along the laser characteristic curve up to an optimal luminance P. opt with a connected current I f Depending on the connected current, the emitted luminance can be adjusted for each laser light source above the laser threshold. The graph on the right, however, shows a sequence of the individual laser characteristics for one pixel as an example. This is intended to illustrate that a comparable optical luminance P can also be achieved using several smaller laser light sources. optas can be achieved using a larger laser light source. Figure 5 also shows, by way of example for a time window, that different pixels 2a, 2b, 2c can be illuminated with different brightness. This can be achieved, on the one hand, by adjusting the emitted luminance of a laser light source (compare L1 pixel 2a and L2 pixel 2b) and / or by increasing the luminance of a pixel by illuminating a pixel with light from multiple laser light sources (L1 + L2 + L3) during the time window, so that the perceived overall brightness of the pixel is increased. 2023PF01221 - 27 - LIST OF REFERENCE SYMBOLS 1 Projection arrangement 5 2, 2a, 2b, 2c, Pixel 2d, 2e 3 Projection surface, projection plane 4 Laser arrangement 5a, 5b, 5c Laser light source 0 6 Deflection module 7 Light-shaping optics L1, L2, L3 Laser light T1, T2 Time window 5 T1, t2, t3 Partial time window 0

Claims

2023PF01221 - 28 - PATENT CLAIMS 1. Projection arrangement (1) for illuminating a plurality of virtual pixels (2, 2a, 2b, 2c), wherein the plurality of virtual pixels (2, 2a, 2b, 2c) produce a first individual image during a first time window (T1), comprising: a laser arrangement (4) with a plurality of laser light sources (5a, 5b, 5c) which are designed to emit laser light (L1, L2, L3) with substantially the same wavelength via a plurality of emission points arranged at a defined distance from one another;a deflection module (6) which is designed to deflect laser light (L1, L2, L3) emitted by the emission points one after the other onto the plurality of virtual pixels (2, 2a, 2b, 2c), and which is designed to deflect laser light (L1) from a first laser light source (5a) onto a first pixel (2a) of the plurality of virtual pixels, laser light (L2) from a second laser light source (5b) onto a second pixel (2b) of the plurality of virtual pixels, and laser light (L3) from a third laser light source (5c) onto a third pixel (2c) of the plurality of virtual pixels during the first time window (T1) within a first partial time window (t1);and a control element which is designed to control the plurality of laser light sources (5a, 5b, 5c) and / or the deflection module (6) in such a way that during the first time window (T1) the third pixel (2c) of the plurality of virtual pixels is illuminated with laser light (L2) from the second laser light source (5b) within a second partial time window (t2) and within a later third partial time window (t3) the third pixel (2c) is illuminated with laser light (L1) from the first laser light source (5a).

2. Projection arrangement according to claim 1, wherein the control element is designed to operate the plurality of laser light sources (5a, 5b, 5c) in a pulsed manner, in particular in such a way that the laser light sources (5a, 5b, 5c) are illuminated within a 2023PF01221 - 29 - partial time window (t1, t2, t3) are operated above their laser threshold for a maximum of 60% of the time, in particular for a maximum of 40% of the time. 5 3. Projection arrangement according to claim 1 or 2, wherein the control element is designed to operate laser light sources (5a, 5b, 5c), which are not intended to emit light within a partial time window (t1, t2, t3), below their laser threshold. 0 4. Projection arrangement according to one of claims 1 to 3, further comprising a light-shaping optics (7) which is arranged between the laser arrangement (4) and the deflection module (6), and which is designed in particular to collimate the laser light (L1, L2, L3) emitted by the laser arrangement (4). 5.Projection arrangement according to one of claims 1 to 4, wherein the control element and / or the deflection module (6) is designed to illuminate a first subset of the plurality of virtual pixels (2, 2a, 2b, 2c) repeatedly with laser light from the plurality of laser light sources (5a, 5b, 5c) during the first time window (T1) and to illuminate a second subset of the plurality of virtual pixels (2, 2a, 2b, 2c) with laser light from one of the plurality of laser light sources (5a, 5b, 5c). 5 6. Projection arrangement according to one of claims 1 to 5, wherein the plurality of virtual pixels (2, 2a, 2b, 2c) are arranged in rows and columns and are in particular arranged equidistant from one another. 0 7. Projection arrangement according to one of claims 1 to 5, wherein the plurality of virtual pixels (2, 2a, 2b, 2c) are arranged closer to one another in a first region than in an adjacent second region. 5 8. Projection arrangement according to one of claims 1 to 7,. 2023PF01221 - 30 - further comprising an ambient light sensor, wherein the control element is designed to illuminate a first subset of the plurality of virtual pixels (2, 2a, 2b, 2c) 5 repeatedly with laser light from the plurality of laser light sources (5a, 5b, 5c) during the first time window (T1) as a function of a sensor signal from the ambient light sensor and to illuminate a second subset of the plurality of virtual pixels (2, 2a, 2b, 2c) with laser light from one of the plurality of laser light sources (5a, 5b, 5c). 0 9. Projection arrangement according to one of claims 1 to 8, wherein the control element and / or the deflection module (6) is designed to illuminate each pixel of the plurality of virtual pixels at most once with laser light (L1, L2, L3) from each of the plurality of laser light sources (5a, 5b, 5c) during a second time window (T2).Data glasses (10) comprising a projection arrangement (1) according to one of claims 1 to 9, wherein the projection arrangement (1) is designed to project the plurality of virtual pixels (2, 2a, 2b, 2c) into at least one eye of a user of the data glasses.

11. Data glasses according to claim 10, further comprising a sensor for detecting the viewing direction of a user of the data glasses, wherein the control element and / or the deflection module (6) is designed to repeatedly illuminate virtual pixels located in a central region of the user's viewing direction with laser light from the plurality of laser light sources (5a, 5b, 5c) during the first time window (T1) and as a function of a sensor signal from the sensor, and to illuminate virtual pixels located in an edge region surrounding the central region with laser light from at most one of the plurality of laser light sources (5a, 5b, 5c). 5 12.Method for illuminating a plurality of virtual pixels (2, 2a, 2b, 2c), wherein the plurality of virtual pixels (2, 2a,. 2023PF01221 - 31 - 2b, 2c) during a first time window (T1) result in a first individual image, comprising the steps of: operating a laser arrangement (4) with a plurality of laser light sources (5a, 5b, 5c) which are designed to emit light 5 with substantially the same wavelength via a plurality of emission points arranged at a defined distance from one another, such that the laser light sources (5a, 5b, 5c) emit laser light (L1, L2, L3) in the direction of a deflection module (6);0 Deflecting the laser light (L1, L2, L3) emitted onto the deflection module (6) successively onto the plurality of virtual pixels (2, 2a, 2b, 2c), wherein the deflection module (6) is designed such that during the first time window (T1) within a first partial time window (t1) laser light (L1) from a first laser light source (5a) is deflected onto a first pixel (2a) of the plurality of virtual pixels, laser light (L2) from a second laser light source (5b) is deflected onto a second pixel (2b) of the plurality of virtual pixels and laser light (L3) from a third laser light source (5c) is deflected onto a third pixel (2c) of the plurality of virtual pixels;0 and controlling the plurality of laser light sources (5a, 5b, 5c) and / or the deflection module (6) such that during the first time window (T1) the third pixel (2c) of the plurality of virtual pixels is illuminated with laser light (L2) from the second laser light source (5b) within a second partial time window (t2) and within a later third partial time window (t3) the third pixel (2c) is illuminated with laser light (L1) from the first laser light source (5a). 0 13. The method according to claim 12, wherein the step of operating the plurality of laser light sources (5a, 5b, 5c) comprises a pulsed operation of the plurality of laser light sources (5a, 5b, 5c), in particular such that the laser light sources (5a, 5b, 5c) are operated above their laser threshold for at most 60% of the time, in particular for at most 40% of the time, within a partial time window 5 (t1, t2, t3); 2023PF01221 - 32 - 14. The method according to claim 12 or 13, wherein the step of operating the plurality of laser light sources (5a, 5b, 5c) comprises operating laser light sources (5a, 5b, 5c) which are provided not to emit light within a partial time window (t1, t2, t3) below their laser threshold.

15. The method according to any one of claims 12 to 14, wherein the step of controlling the plurality of laser light sources (5a, 5b, 5c) and / or the deflection module (6) comprises illuminating a first subset of the plurality of virtual pixels (2, 2a, 2b, 2c) multiple times with laser light from the plurality of laser light sources (5a, 5b, 5c) during the first time window (T1), and illuminating a second subset of the plurality of virtual pixels (2, 2a, 2b, 2c) with laser light from at most one of the plurality of laser light sources (5a, 5b, 5c).Method according to one of claims 12 to 15, wherein the step of controlling the plurality of laser light sources (5a, 5b, 5c) and / or the deflection module (6) comprises projecting the plurality of virtual pixels (2, 2a, 2b, 2c), in particular, onto a projection surface (3) or a projection plane in rows and columns, wherein the virtual pixels are arranged in particular equidistant from one another; or projecting the plurality of virtual pixels (2, 2a, 2b, 2c), in particular, onto a projection surface (3) or a projection plane in a first region with a closer distance to one another than in an adjacent second region.Method according to one of claims 12 to 16, wherein the step of controlling the plurality of laser light sources (5a, 5b, 5c) and / or the deflection module (6) comprises that during a second time window (T2) each pixel of the plurality of virtual pixels is illuminated at most once with laser light (L1, L2, L3) of each individual one of the plurality of laser light sources (5a, 5b, 5c).

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