projector

Abstract

A projector (100) is specified, said projector (100) comprising - an optoelectronic device (10) having a plurality of optoelectronic units (11), - a projection arrangement (20) for projecting the radiation emitted by the optoelectronic device (10) onto a surface (200), wherein - at least some of the optoelectronic units (11) are configured to emit radiation in a first operation state (S1) and to detect radiation in a second operation state (S2), - at least some of the optoelectronic units (11) are controllable independently from each other so that different images can be projected and the radiation is detectable with spatial resolution. The optoelectronic units may comprise µLEDs.

Description

[0001] PROJECTOR

[0002] A projector for projecting an image onto a surface is specified.

[0003] One object to be achieved is to provide an improved projector, for example a particularly compact projector.

[0004] According to at least one aspect, the projector for projecting an image onto a surface comprises an optoelectronic device. The optoelectronic device comprises a plurality of optoelectronic units. The optoelectronic device is, for example, configured to produce and emit visible light. Further, the optoelectronic device is, for example, configured to detect electromagnetic radiation, for example visible light or infrared radiation. By way of example, the optoelectronic device comprises at least four or at least 10 or at least 100 or at least 10000 or at least 1 million optoelectronic units. The optoelectronic units may also be called image points or pixels of the projector.

[0005] According to at least one aspect, the projector comprises a projection arrangement for projecting the radiation emitted by the optoelectronic device, for example, onto a surface. Particularly, the projection arrangement is configured to redirect and / or focus and / or disperse the radiation emitted by the optoelectronic device by means of reflection, refraction and / or diffraction.

[0006] The surface onto which the radiation may be projected may be a screen or a wall or a glass plate or a street. The projector may be used in a beamer or in a vehicle, like a car. The projector may be arranged in the vehicle and may be configured to project an image onto the street in front of the door when a passenger enters or exits the vehicle via said door. For example, the projector projects the brand of the vehicle onto the street. The projector could also be used in the interior of a vehicle and may project an image onto a surface in the interior of the vehicle. For example, the projector is then used for decorative or functional lighting. The projector may also be used to realize a head-up display. For example, the projector then projects an image onto the windshield of the vehicle.

[0007] According to at least one aspect, the optoelectronic units are each configured to emit radiation when operated. For example, the optoelectronic device comprises a radiation surface, via which the major part or all of the radiation emitted by the optoelectronic device is emitted. The optoelectronic units may be laterally arranged next to each other, wherein a lateral direction is a direction parallel to the radiation surface. The optoelectronic units may be arranged in a two-dimensional pattern. For example, each optoelectronic unit is assigned an area of the radiation surface on a one-to-one basis. Thus, when an optoelectronic unit emits radiation, radiation is emitted via the assigned area of the radiation surface.

[0008] An optoelectronic device comprising a plurality of optoelectronic units is herein understood to be a device that itself generates the radiation and emits the radiation via the optoelectronic units. Particularly, each optoelectronic unit is assigned a certain area of the optoelectronic device on a one-to-one basis , wherein radiation is generated within said area and / or emitted via said area .

[0009] According to at least one aspect of the proj ector, at least some of the optoelectronic units are configured to emit radiation in a first operation state and to detect radiation in a second operation state . It is possible that more than 50 % , more than 75 % or all optoelectronic units are configured to emit radiation in the first operation state and to detect radiation in the second operation state . Further, it is possible that only some of the optoelectronic units can be operated in both operation states and some of the optoelectronic units are configured to work only in one of the operation states , for example in the first operation state for emitting radiation like regular light-emitting diodes or in the second operation state for detecting radiation in the second operation state like regular photodiodes .

[0010] In the second operation state in which radiation is detected by the optoelectronic unit , the optoelectronic unit in particular detects radiation from outside the proj ector . For example , this radiation is radiation which is reflected by an obj ect like , for example , a human body or part of a human body .

[0011] Thereby it is also possible that all of the optoelectronic units are controllable independently from each other . In particular, the optoelectronic units which are configured to emit radiation in the first operation state and to detect radiation in the second operation state are controllable independently from each other . With this it is possible that di f ferent images can be proj ected . Further it is possible that the radiation is detectable with a spatial resolution . Further, it is possible that some of the optoelectronic units are operated in the first operation state and emit radiation at the same time , whereas some of the optoelectronic units are operated in the second operation state and detect radiation at the same time . In this way it is possible that an image can be proj ected and radiation can be detected at the same time .

[0012] According to one aspect of the proj ector, the proj ector comprises

[0013] - an optoelectronic device having a plurality of optoelectronic units ,

[0014] - a proj ection arrangement for proj ecting the radiation emitted by the optoelectronic device , wherein

[0015] - at least some of the optoelectronic units are configured to emit radiation in a first operation state and to detect radiation in a second operation state ,

[0016] - at least some of the optoelectronic units are controllable independently from each other .

[0017] The here described proj ector inter alia relies on the idea that a proj ector in which at least some of the optoelectronic units are configured to emit radiation in the first operation state and to detect radiation in the second operation state can be built particularly small as no space has to be assigned, for example , for additional detector chips like photodiodes , but it is possible to use the same radiationemitting unit to detect radiation . With this , a very small proj ector, for example a pico-pro j ector , can be reali zed which proj ects images and is adapted to sense , for example , simple gestures by a user at the same time . This enables an interactive proj ection by the proj ector . In particular such a proj ector is very compact . Further, such a proj ector can be programmable to proj ect di f ferent images based on interactions with a user . Due to the reduced si ze , such a proj ector can be produced very cost-ef fectively, it is lightweight and has a lower power consumption than a proj ector which uses dedicated units for emitting and detecting radiation, respectively .

[0018] According to at least one aspect of the proj ector, the proj ector comprises

[0019] - an optoelectronic device having a plurality of optoelectronic units ,

[0020] - a proj ection arrangement for proj ecting the radiation emitted by the optoelectronic device for generating images , and

[0021] - a control device , wherein

[0022] - at least some of the optoelectronic units are configured to emit radiation in a first operation state and to detect reflected radiation in a second operation state ,

[0023] - at least some of the optoelectronic units are controllable independently from each other,

[0024] - the control device is configured to determine a gesture from the reflected radiation, and

[0025] - the generation of the images is controllable by the gesture .

[0026] According to at least one aspect of the proj ector, part of the radiation used to generate the images is detected as the reflected radiation and used to determine the gesture . Thus , a simple man-machine interface can be reali zed with the proj ector and the proj ected image can be used to communicate with the proj ector . In fact , there is no need for an additional light source to generate the radiation used to detect the gesture, but the same radiation which is used to generate the images, is used for determining a gesture and / or an object. According to this aspect, the projector is free of any additional light source, e.g. an infrared light source which is used for determining a gesture and / or an object and not for projecting an image.

[0027] According to one aspect of the projector, the optoelectronic units are operated with a forward bias in the first operation state and with a reverse bias in the second operation state. For this the optoelectronic units, for example, each comprise one or more light-emitting diodes. In the first operation state at least one of said light-emitting diodes, for example all of the light-emitting diodes, is operated with a forward bias. In the second operation state at least one or all light-emitting diodes are operated with a reverse bias. For this, each light-emitting unit may comprise a driver for operating its light-emitting diodes in the different operation states. Further, light-emitting units which are operable in the second operation state may comprise at least one amplifier for amplifying the detected signal.

[0028] The bias may be provided by means of a control circuit which may be part of a control device of the projector. The control circuit is electrically connected to optoelectronic units.

[0029] For example, the control circuit is configured to address the optoelectronic units individually. The control circuit provides a bias to the optoelectronic units by way of the electrical connections. Which bias is applied to the pixels is defined according to the state of operation of the optoelectronic units. Depending on the state of operation, optoelectronic units can be operated as light detector or emitter. For example, reverse biasing of an LED allows for ef ficient photo detection using the Stark Ef fect or Quantum- Confined Stark-Ef f ect . In this way, an optoelectronic unit can absorb and detect visible or IR light .

[0030] According to one aspect of the proj ector, at least some of the optoelectronic units are operated alternately in the first and the second operating states . For example , depending on the image which is proj ected by the proj ector, some of the optoelectronic units can be operated in the first operation state and other optoelectronic units can be operated in the second operation state . For example , a user interaction causes - detected by optoelectronic units in the second operation state - the proj ection of a di f ferent image for which some of the light-emitting units in the first operation state are switched to the second operation state and vice versa . Alternatively it is also possible that all lightemitting units are operated in the first operation state for certain times and all optoelectronic units are operated in the second operation state for second times . For example , this can be controlled by a pulse width modulation circuit which may be implemented in a control device of the proj ector . In this embodiment the optoelectronic units are switched from light-emitting to a sensing function for certain times during a duty cycle .

[0031] According to one aspect of the proj ector, the proj ector further comprises a control device which is configured to determine an obj ect and / or a gesture from the detected radiation . For example , the control device is configured to detect the proximity of an obj ect like , for example , a human . Further, the control device can be configured to detect a gesture , for example from this human . The gesture can, for example , be a simple gesture like a swiping gesture or a waving gesture. For example, the control device is configured to differentiate between swiping gestures in different directions. In this way, the user can, for example, choose an image from a number of pre-stored images which the projector projects during operation. Thereby, the swipe in a certain direction can initiate the generation of an image out of a group of pre-stored images.

[0032] Further, for example the control device can be configured to recognize a tapping gesture for switching the projector on and off.

[0033] In the case that the projector is switched off, none of the optoelectronic units is operated in the first operation state but at least some of the optoelectronic units can be operated in the second operation state to allow for the detection of another gesture which initiates the generation of an image and turns the projector in the on-state.

[0034] According to at least one aspect, the projection arrangement comprises a plurality of projection channels. Each projection channel has at least one optical element for beam shaping. The optical element is, for example, a lens or an optical aperture or a mirror or a prism. Each projection channel having at least one optical element particularly means that different projection channels comprise different optical elements. For example, each projection channel has at least one optical element, like a lens, uniquely assigned to that projection channel. Optical elements of different projection channels may be separated, for example spaced, from each other. Alternatively, the optical elements of different projection channels may be connected and may even be formed in one piece. According to at least one aspect, each projection channel is configured to project radiation, particularly radiation from the optoelectronic device, incident on or into the projection channel, respectively, into a certain area of the surface and vice versa. That is to say, radiation which is to be detected by an optoelectronic unit operated in the second operation state is projected through a projection channel onto the optoelectronic unit.

[0035] Each projection channel may comprise two or more optical elements which are, for example, arranged one after the other along the optical path of the projection channel. The optical path of the projection channel is the path along which the radiation is guided within the projection channel. The projection channels may be arranged next to each other in a direction oblique or perpendicular to the optical paths.

[0036] The projection channels are, in particular, configured to project radiation onto different areas of the surface and to receive radiation from these areas. Thus, each projection channel may be uniquely assigned a certain area of the surface, wherein each two areas assigned to different projection channels do not overlap or at least do not completely overlap. This also allows for a spatial resolution of the detected radiation.

[0037] According to at least one aspect, at least some, for example all, optoelectronic units of the optoelectronic device are each uniquely assigned to a projection channel such that radiation from and to the optoelectronic unit is at least predominantly, for example solely, incident on or into the respective projection channel. The projection arrangement may comprise the same number of projection channels as the optoelectronic device comprises optoelectronic units.

[0038] With the optoelectronic units each being uniquely assigned to a projection channel, each optoelectronic unit may be uniquely assigned to an image point or pixel of the image projected onto the surface.

[0039] According to at least one aspect, at least some optoelectronic units are controllable independently of other optoelectronic units. Thus, different images can be projected onto the surface by changing the control of the optoelectronic units without changing the projection arrangement .

[0040] By controlling an optoelectronic unit, the optoelectronic unit is operated, i.e. generates and emits or detects radiation. Two optoelectronic units are controllable independently of each other, if one of the two optoelectronic units can be operated such that it emits radiation while, at the same time, the other optoelectronic unit is turned off, i.e. does not emit radiation and / or detect radiation.

[0041] Projectors may comprise a single light source, the light of which is incident on a projection arrangement. The projection arrangement may then comprise a mask with opaque and transparent areas and thereby defines the image which is projected onto a surface. In this case, the image is fixed and cannot be changed.

[0042] On the other hand, there are projectors which use one single light source, like an LED, and the radiation thereof is incident on a projection arrangement in the form of a DMD ( Digital Micromirror Device ) or in the form of an LCD ( Liquid Crystal Display) . The micro mirrors of the DMD are movable independently of each other . The beam of the light source is then split into several beams by the movable micromirrors and then reflected in order to proj ect an image onto a surface . This approach is expensive and requires a complicated mirror control .

[0043] The present invention is , inter alia, based on the recognition that by using an optoelectronic device or light source , respectively, which itsel f already comprises a plurality of optoelectronic units , the distance of the optoelectronic device to the proj ection arrangement can be reduced . Indeed, in proj ectors using a radiation source with only one optoelectronic unit , the radiation first has to be dispersed in order to get a suf ficiently large beam spot for a proj ection arrangement . Dispersing requires collimation optics arranged between the radiation source and the proj ection arrangements . Thus , additional space is required between the radiation source and the proj ection arrangement .

[0044] By using an optoelectronic device which already comprises a plurality of optoelectronic units , collimation optics can be dismissed so that the extensions of the proj ector can be reduced . This can be particularly beneficial when using such a proj ector in a vehicle , where space is limited .

[0045] According to at least one aspect , the proj ection arrangement comprises a lens array, e . g . a microlens array . At least some of the optoelectronic units have a lens of the lens array uniquely assigned thereto . A lens of the lens array being uniquely assigned to a radiation emitting unit means that at least a maj or part of the radiation emitted or detected by that optoelectronic unit goes through the respective lens .

[0046] The lens array may comprise as many lenses as the optoelectronic device comprises optoelectronic units .

[0047] The lenses of the lens array may be arranged in the proj ection channels . For example , at least some or all lenses of the lens array are each uniquely assigned to a proj ection channel . For example , the diameter of a proj ection channel is determined by the largest diameter of a lens uniquely assigned to that proj ection channel .

[0048] A lens array is a structure comprising a plurality of lenses mechanically connected and fixed to each other . The lenses of the lens array are arranged, for example , in a two- dimensional pattern constituting a layer of lenses . The lens axes of the lenses are each orientated obliquely or perpendicularly to the layer, for example . A microlens is herein understood as a lens having a diameter of at most 1 mm or at most 100 pm or at most 50 pm . The lenses of the lens array may be focusing lenses or dispersing lenses . For example , the lenses of the lens array are arranged on a common substrate . The substrate is , in particular, transparent for the radiation of the optoelectronic device .

[0049] According to at least one aspect , the proj ection arrangement comprises two or more lens arrays , particularly microlens arrays , which are arranged one after the other . "One after the other" particularly means one after the other in a direction along the optical paths of the proj ection channels . All features disclosed so far and in the following for one lens array are also disclosed for the other lens arrays . Two lens arrays , namely the lenses thereof , may be arranged on opposite sides of a common substrate . According to at least one aspect, at least some projection channels, for example all projection channels, each have at least two lenses of different lens arrays uniquely assigned thereto. Both lenses may be microlenses. The lenses assigned to a projection channel are, for example, arranged one after the other in a direction parallel to the optical path of the respective projection channels. Thus, radiation incident on the radiation channel first hits one of the at least two lenses and, afterwards, hits the other one of the at least two lenses.

[0050] For example, at least some or all of the projection channels each comprise at least one focusing lens and at least one dispersing lens.

[0051] According to at least one aspect, the projection arrangement comprises several optical apertures. An optical aperture is herein particularly understood to be an opening in an opaque element, wherein radiation can pass through the opening.

[0052] According to at least one aspect, at least some of the projection channels, for example all projection channels, each have an optical aperture uniquely assigned thereto.

[0053] At least some optical apertures may be formed in a common opaque element of the projection arrangement. For example, the projection arrangement comprises a contiguous, opaque layer which is interrupted by a plurality of openings, wherein each opening constitutes an optical aperture. The opaque layer may be formed of chrome, for example. The opaque layer may be formed on or in the common substrate, on which the lenses of at least one lens array are arranged. By way of example , the optical apertures assigned to the di f ferent proj ection channels are in each case arranged between the at least two lenses of the respective proj ection channel in a direction along the optical path of the respective proj ection channel .

[0054] According to at least one aspect , the optoelectronic device comprises a plurality of LEDs . Each LED is or comprises a LED-chip or optoelectronic semiconductor chip, respectively . Semiconductor bodies of di f ferent LEDs are separated and spaced from each other . For example , the LEDs are mounted on a common carrier . The LEDs may also be electrically connected to the common carrier .

[0055] Further, it is possible that the optoelectronic device comprises at least one photodiode .

[0056] According to at least one aspect , each LED is uniquely assigned to an optoelectronic unit . Thus , the radiation emitted or detected by an optoelectronic unit is at least partially produced or absorbed by the assigned LED .

[0057] According to at least one aspect , at least two LEDs are uniquely assigned to each optoelectronic unit . Thus , the radiation emitted or detected by such an optoelectronic unit is at least partially produced or absorbed by one or both assigned LEDs . Thereby it is also possible , that at least one LED and at least one photodiode are assigned to each optoelectronic unit .

[0058] According to at least one aspect , the at least two LEDs are configured to emit or detect di f ferent types of radiation, i.e. radiation of different wavelengths. For example, each optoelectronic unit is assigned a first LED configured to emit or detect radiation of a first color, like blue light, and a second LED configured to emit or detect radiation of a second color, like green light or red light. Each optoelectronic unit may also be assigned a third LED configured to emit or detect radiation of a third color, like green light. Particularly, each optoelectronic unit may be assigned at least three LEDs which are configured to emit or to detect different types of radiation, for example blue light, green light and red light.

[0059] Thus, the different optoelectronic units of the optoelectronic device may each be realized by at least one or at least two, for example by three, different LEDs. Alternatively, the optoelectronic device may be realized by one single, pixelated LED having one contiguous semiconductor body. The different optoelectronic units may each be uniquely assigned a region of the semiconductor body.

[0060] According to at least one aspect, each LED is a pLED, also called "micro-LED". A micro-LED is a light emitting diode (LED) , particularly not a laser, with a particularly small size. A growth substrate for the semiconductor layer sequence of the micro-LED is removed from the micro-LED so that a height / thickness of a micro-LED is in the range of 1.5 pm to 10 pm, for example. In principle, a micro-LED could, but does not necessarily have to, have a rectangular radiation emission surface. For example, a micro-LED has a radiation emission surface in which, in plan view of the layers of the layer stack, any lateral extent of the radiation emission surface is less than or equal to 100 pm or less than or equal to 70 pm. For example, in the case of a rectangular micro- LED, an edge length - especially in plan view of the layers of the layer stack - may be smaller than or equal to 70 pm or smaller than or equal to 50 pm.

[0061] According to at least one aspect, each LED is a mini LED. Mini-LEDs, in contrast to pLEDs, still have the growth substrate adhering to them, resulting in a thickness of 50 - 100 pm.

[0062] According to at least one aspect, each optoelectronic unit is independently controllable of the other optoelectronic units. Thus, each optoelectronic unit can emit or detect radiation independently of the other optoelectronic units. For example, each optoelectronic unit is uniquely assigned a switch, like a thin-film transistor, TFT for short. The switches may be arranged in or on the common carrier or are part of the optoelectronic unit. With the help of the switches, the different optoelectronic units can be controlled, e.g. turned on or off and the operation state can be selected.

[0063] For example, the projector is programmable so that various and arbitrary images can be produced with the optoelectronic device. Alternatively, a limited number of images can be predefined so that only these images can be produced by the optoelectronic device.

[0064] According to at least one aspect, the projection arrangement is static. This means that, during operation, the properties of the projection arrangement, particularly the properties, positions, orientations and / or relative arrangements of the optical elements of the projection arrangement, are not changed. A variation of the projected image is, for example, achieved or achievable, particularly solely achieved or achievable, by a variation of the control of the optoelectronic units.

[0065] According to at least one aspect, the projection arrangement comprises a plurality of primary lenses. A primary lens is herein understood to be a first lens of the projection arrangement onto which radiation emitted by the optoelectronic device hits. For example, no optical element, or at least no lens, is arranged between a primary lens and the assigned optoelectronic device.

[0066] According to at least one aspect, each primary lens is assigned an optoelectronic unit, e.g. on a one-to-one basis. The primary lenses may be part of a lens array. The primary lenses may be microlenses and, accordingly, the lens array may be a microlens array.

[0067] According to at least one aspect, the primary lenses are arranged immediately downstream of the assigned optoelectronic units. "Downstream" here means downstream in a direction of the main emission direction of the optoelectronic units. "Immediately downstream" means, for example, that the primary lenses are arranged on and in mechanical contact with the optoelectronic units.

[0068] According to at least one aspect, the LEDs are at least partially embedded in the primary lenses. For example, the LEDs are form-f ittingly surrounded by the primary lenses. Particularly, the primary lenses are formed around the LEDs assigned thereto. With this, a higher coupling efficiency can be achieved and stray light can be eliminated. According to at least one aspect, at least some optical elements of the projection arrangement are embedded in a cover layer so that the cover layer form-f ittingly surrounds the optical elements at least in places. For example, all lenses of a lens array, particularly primary lenses, are embedded in the cover layer. The cover layer may be a contiguous layer. The cover layer is, in particular, a transparent layer.

[0069] According to at least one aspect, the cover layer and the optical elements embedded therein are formed of a polymer, particularly of a photopolymer. For example, the optical elements and the cover layer are both based on polymers having the same basic structure. For example, the polymers of the optical elements and of the cover layer are different from each other only by one monomer of the polymer. The cover layer and the optical elements embedded therein are, for example, formed in one piece, from a common layer of a starting material.

[0070] According to at least one aspect, the cover layer and the optical elements embedded therein have different refractive indices. Particularly, the optical elements have a higher reflective index than the cover layer. The refractive index of the optical elements may deviate from the refractive index of the cover layer by at least 0.01 or at least 0.015. The refractive index hereby means the refractive index for the radiation of the optoelectronic device and / or for radiation in the visible range, for example at 500 nm wavelength.

[0071] According to at least one aspect, at least some of the projection channels, for example all projection channels, are each assigned at least two optoelectronic units of the optoelectronic device such that radiation from the at least two assigned optoelectronic units is at least predominantly, e.g. completely, incident on or into the respective projection channel. Thus, with the help of the projection arrangement, radiation from two different optoelectronic units is projected into the same area of the surface, i.e. together they form one pixel of the image.

[0072] Using a projector in which the projection channels are each assigned two or more optoelectronic units can help to increase the brightness of the projected image.

[0073] Hereinafter, the projector will be explained in more detail with reference to the drawings on the basis of exemplary embodiments. The accompanying figures are included to provide a further understanding. In the figures, elements of the same structure and / or functionality may be referenced by the same reference signs. It is to be understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale. In so far as elements or components correspond to one another in terms of their function in different figures, the description thereof is not repeated for each of the following figures. For the sake of clarity, elements might not appear with corresponding reference symbols in all figures.

[0074] Figure 1 shows exemplary embodiments of the projector,

[0075] Figure 2A shows an exemplary embodiment of an optoelectronic device for an embodiment of a here described projector in plan view, Figure 2B shows an exemplary embodiment of an optoelectronic unit for an embodiment of a here described proj ector,

[0076] Figure 2C shows an exemplary embodiment of an optoelectronic unit for an embodiment of a here described proj ector,

[0077] Figure 3 shows an exemplary embodiment of the proj ector,

[0078] Figure 4 shows an exemplary embodiment of the use of an embodiment of a here described proj ector .

[0079] Figure 5 shows an exemplary embodiment of the function of an embodiment of a here described proj ector .

[0080] Figure 1 shows a first exemplary embodiment of the proj ector 100 . The proj ector 100 comprises an optoelectronic device 10 and a proj ection arrangement 20 .

[0081] The optoelectronic device 10 comprises a carrier 12 on top of which a plurality of LEDs 15 is arranged . Each LED 15 is , for example , configured to emit visible light , for example white light . Each LED 15 constitutes an optoelectronic unit 11 of the optoelectronic device 10 . For example , the LEDs 15 and, hence , the optoelectronic units 11 are individually and independently controllable so that each LED 15 or optoelectronic unit 11 , respectively, can emit or detect radiation independently of the other LEDs 15 or optoelectronic units 10 . For this purpose , the carrier 12 may comprise a plurality of switches , wherein each switch is assigned to a LED 15 and each switch is configured to turn the respective LED 15 on or of f or select the operation state - also see figures 2B and 2C . The switches may be thin- film- transistors . For example , the proj ector is completely programmable so that it is configured to produce various and arbitrary images by varying the control of the optoelectronic units 11.

[0082] The projection arrangement 20 is configured to project the radiation emitted by the optoelectronic device 10 onto a surface 200. By way of example, the projector 100 is installed in a car, and, when a door of the car is opened, the projector 100 projects the image generated by the optoelectronic device 10 onto the street directly adjacent to the car.

[0083] The projection arrangement 20 comprises a plurality of projection channels 21, wherein each projection channel 21 is uniquely assigned an optoelectronic unit 11 or LED 15, respectively. The radiation 43 emitted by the respective optoelectronic unit 11 is predominantly or completely incident on the projection arrangement 20 in the area of the assigned projection channel 21. The projection channels 21 each guide the incident radiation and project the radiation onto a predefined area on the surface 200. In figure 1, the virtual border between each two adjacent projection channels 21 is indicated by a dashed line.

[0084] By changing the control of the optoelectronic units, different images can be projected onto the surface 200. This may be done without changing the projection arrangement 20 itself. The projection arrangement 20 is, in particular, static .

[0085] Figure 1 shows that some of the optoelectronic units 11 are configured to emit radiation 43 in a first operation state SI and to detect radiation 42 in a second operation state S2. For this , for example , radiation 42 which is reflected from an obj ect 40 is led back to one of the optoelectronic units 11 which is operated in the second operation state and therefore detects the reflected radiation 42 . Thereby it is , for example , possible to detect the direction 41 in which the obj ect 40 is moving by using more than one optoelectronic unit 11 which is operated in the second operation state . The control device 16 is configured to determine the obj ect 40 , for example the movement of the obj ect 40 in this direction 41 . Thereby, the proj ector can sense the proximity of an obj ect 40 . Further, it is possible that the control device 16 is configured to determine a gesture 50 from the detected radiation 42 which is reflected from the obj ect 40 .

[0086] In the exemplary embodiment of figure 1 , the proj ection arrangement 20 comprises three microlens arrays MLA comprising a plurality of microlenses 22 , 23 , 24 . In each microlens array MLA, the respective microlenses are connected to each other . A first microlens array MLA comprises primary lenses 22 , a second microlens array MLA comprises second microlenses 23 and a third microlens array comprises third microlenses 24 . The microlens arrays are arranged one after the other .

[0087] Each proj ection channel 21 has a primary lens 22 , a second lens 23 and a third lens 24 of the three microlens arrays MLA assigned thereto . Moreover, each proj ection channel 21 has an optical aperture 25 assigned thereto . The primary lenses 22 are arranged on a substrate . The substrate and the primary lenses 22 are made from a transparent material , like glass or plastic . The second lenses 23 and the third lenses 24 are arranged on di f ferent sides of a further substrate . Also the second lenses 23 and third lenses 24 as well as the further substrate are made of a transparent material , like glass or plastic . Furthermore , an opaque layer, e . g . of chrome , is formed on the further substrate . A plurality of openings is formed in the opaque layer and each opening constitutes an optical aperture 25 .

[0088] For an optoelectronic unit 11 in the first operation state S I , the primary lenses 22 focus the radiation of the optoelectronic units 11 onto the second lenses 23 . The second lenses 23 further focus the radiation onto the apertures 25 . The radiation passing through the apertures 25 is then directed to the predefined certain area on the surface 200 with the help of the third lenses 24 . The path of di f ferent rays of the uppermost optoelectronic unit 11 is indicated in figure 1 .

[0089] Alternatively, each proj ection channel 21 can be assigned to two or more radiation-emitting units . As a consequence , radiation from these radiation-emitting units 11 is proj ected onto the same predefined area on the surface 200 . Therefore , the brightness is increased . However, this decreases the image resolution in the first operation state S2 and the spatial resolution in the second operation state S2 .

[0090] Figure 2A shows a plan view of an exemplary embodiment of an optoelectronic device 10 , e . g . of the optoelectronic device 10 of figure 1 . The optoelectronic units 11 are arranged in a two-dimensional pattern on the carrier 12 . The lenses of the di f ferent microlens arrays may be arranged in a corresponding two-dimensional pattern . Figure 2A further shows that the control device 16 is connected with the optoelectronic device 10 in order to determine an obj ect 40 and / or a gesture 50 from radiation 42 detected by those of the optoelectronic units 11 which are operated in the second operation state S2 . Further, the control device 16 can be configured to operate the optoelectronic units in their di f ferent operation states . That is to say, the control device 16 can also be configured to control the optoelectronic units 11 in order to be operated in one of the operation states S I , S2 .

[0091] For example , it is then possible that at least some of the optoelectronic units 11 are operated alternately in the first and in the second operation states S I , S2 .

[0092] Figure 2B shows an optoelectronic unit 11 with, for example , a single LED 15 in the first operation state S I in which a driver 17 of the optoelectronic unit 11 is configured to drive the LED 15 with a forward bias and radiation 43 is emitted .

[0093] Figure 2C shows a schematic figure of an optoelectronic unit 11 which is operated in the second operation state S2 in which the LED 15 is operated with a reverse bias in order to detect reflected radiation 42 . As can be seen from Figure 2C, it is possible that the driver 17 comprises an ampli fier which ampli fies the detected signal in order to facilitate , for example , the recognition of gestures by the control device 16 .

[0094] Figure 3 shows a second exemplary embodiment of the proj ector 100 . The proj ector 100 of figure 3 is similar to that of figure 1 . In contrast to the first exemplary embodiment , however, each optoelectronic unit 11 is here reali zed by three LEDs 15 . The three di f ferent LEDs 15 of each optoelectronic unit 11 are configured to emit radiation of di f ferent colors . For example , one LED is , in each case , configured to emit blue light, one LED 15 is, in each case, configured to emit green light and one LED 15 is, in each case, configured to emit red light. The different LEDs 15 of each optoelectronic unit 11 may be independently controllable so that the color of the light emitted by each optoelectronic unit 11 can be controlled.

[0095] For the embodiment of Figure 3, it is, for example, possible that each of the three different LEDs 15 is operated in the second operation state S2 when the associated optoelectronic unit 11 is operated in this operation state. With this it is possible to enhance the spatial resolution of the detection, for example of gestures 50, and it is possible that more complicated gestures like, for example, the numbers of fingers shown by a hand, are recognized by the control device 16.

[0096] Figure 4 shows an exemplary embodiment of the use of an embodiment of a here described projector. For example, the projector has three pre-stored images which can be chosen by a swiping gesture 50 along a lateral direction. With this, for example, a decorative lighting can be realized indoors or outdoors. The user can then choose between different images of this lighting in an easy manner.

[0097] Figure 5 shows an exemplary embodiment of the function of an embodiment of a here described projector. In this embodiment of the projector 100 some of the optoelectronic units 11 are operated in the first operation state SI and an image, for example, of a switch is projected onto the surface 200.

[0098] Others of the optoelectronic units 11 are operated in the second operation state S2 and detect reflected light 42. Therefore, in a first step Al, the image is projected. In a second step A2, a user interaction takes place. For example, the user interaction is a tapping gesture 50 in the region of the projected image. Accordingly in step A3, reflected radiation 42 is detected by the optoelectronic units 11 which are operated in the second operation state S2 and in the step A4 feedback is given to the projector 100. With this, a simple human machine interface can be realized with the projector 100 and the projected image can be used to communicate with the projector 100. For example, the image projection can be switched off by the tapping gesture 50.

[0099] A here described projector can be used for interior and exterior decorative and functional lighting, for dynamic signalling, for head-up displays and for Augmented Reality (AR) and Virtual Reality (VR) applications. Other applications of the projectors described here include domestic appliances such as white goods, e.g. projection from a dishwasher or refrigerator, e.g. of the operating mode. Other applications include projection in medical equipment, e.g. projection of a warning from a monitoring device. Applications can also include alarm systems, e.g. a fire alarm system projecting alarms onto a floor. Other applications may include industrial robots projecting their path onto the floor to help people avoid colliding with them.

[0100] In particular a here described projector can also be used for backlighting of a display, for example for backlighting of an LCD display. With this it is possible to have emission of radiation and detection of radiation integrated in the display without the need for dedicated sensors for detecting the radiation. The invention described herein is not limited by the description in conj unction with the exemplary embodiments . Rather, the invention comprises any new feature as well as any combination of features , particularly including any combination of features in the patent claims , even i f said feature or said combination per se is not explicitly stated in the patent claims or exemplary embodiments .

[0101] This patent application claims the priority of German patent application 102023123332 . 7 , the disclosure content of which is hereby incorporated by reference .

[0102] References

[0103] 10 optoelectronic device

[0104] 11 optoelectronic unit

[0105] 12 carrier

[0106] 15 LED

[0107] 16 control device

[0108] 17 driver

[0109] 20 proj ection arrangement

[0110] 21 proj ection channel

[0111] 22 primary lenses

[0112] 23 second lens

[0113] 24 third lens

[0114] 25 optical aperture

[0115] 40 obj ect

[0116] 41 direction

[0117] 42 reflected radiation

[0118] 43 emitted radiation

[0119] 50 gesture

[0120] 100 proj ector

[0121] 200 surface

[0122] MLA microlens array

[0123] Al . . A4 steps

Claims

Claims1. A projector (100) comprising- an optoelectronic device (10) having a plurality of optoelectronic units (11) ,- a projection arrangement (20) for projecting the radiation emitted by the optoelectronic device (10) for generating images, and- a control device (16) , wherein- at least some of the optoelectronic units (11) are configured to emit radiation in a first operation state (SI) and to detect reflected radiation in a second operation state (S2) ,- at least some of the optoelectronic units (11) are controllable independently from each other,- the control device (16) is configured to determine a gesture (50) from the reflected radiation (42) , and- the generation of the images is controllable by the gesture (50) .

2. Projector (100) according to the previous claim, wherein the optoelectronic units (11) are operated with a forward bias in the first operation state (SI) and with a reverse bias in the second operation state (S2) .

3. Projector (100) according to at least one of the previous claims, wherein at least some of the optoelectronic units (11) are operated alternately in the first and second operating states.

4. Projector (100) according to at least one of the previous claims, wherein the control device (16) is configured to determine an object (40) .

5. Projector (100) according to at least one of the previous claims, wherein- the projection arrangement (20) comprises a plurality of projection channels (21) , each projection channel (21) having at least one optical element (22 to 25) for beam shaping,- each projection channel (21) is configured to project radiation incident on the projection channel (21) into a certain area of the surface (200) or from a certain area of the surface (200) ,- at least some optoelectronic units (11) of the optoelectronic device (10) are each uniquely assigned to a projection channel (21) such that radiation from the assigned optoelectronic unit (11) is at least predominantly incident on the respective projection channel (21) .

6. Projector (100) according to at least one of the previous claims, wherein the different images can be projected onto the surface (200) by changing the control of the optoelectronic units (10) without changing the projection arrangement (20) .

7. Projector (100) according to least one of the previous claims, wherein- the projection arrangement (20) comprises a microlens array (MLA) ,- at least some of the radiation channels (21) each have a microlens (22, 23, 24) of the microlens array (MLA) uniquely assigned thereto.

8. Projector (100) according to the previous claim, wherein- the projection arrangement (20) comprises at least two microlens arrays (MLA) arranged one after the other,at least some projection channels (21) each have at least two microlenses (22, 23, 24) of different microlens arrays (MLA) uniquely assigned thereto and arranged one after the other .

9. Projector (100) according to at least one of the previous claims, wherein- the projection arrangement (20) comprises several optical apertures (25) ,- at least some of the projection channels (21) each have an optical aperture (25) uniquely assigned thereto.

10. Projector (100) according to at least one of the previous claims, wherein- the optoelectronic device (10) comprises a plurality of LEDs (15) ,- each LED (15) is uniquely assigned to an optoelectronic unit (11) .

11. Projector (100) according to the previous claim, wherein- the LEDs (15) are pLEDs or mini LEDs.

12. Projector (100) according to one of the two previous claims, wherein- at least two LEDs (15) are uniquely assigned to each optoelectronic unit (11) ,- the at least two LEDs (15) are configured to emit different types of radiation.

13. Projector (100) according to at least one of the previous claims, wherein- each optoelectronic unit (11) is independently controllable of the other optoelectronic units (11) so that it can emitand detect radiation independently from the other optoelectronic units (11) .

14. Projector (100) according to at least one of the previous claims, wherein- the projection arrangement (20) is static and a variation of the projected image is achieved by a variation of the control of the optoelectronic units (11) .

15. Projector (100) according to at least one of the previous claims ,- wherein the projection arrangement (20) comprises a plurality of primary lenses (22) ,- each primary lens (22) is assigned an optoelectronic unit (11) ,- the primary lenses (23) are arranged immediately downstream of the assigned optoelectronic units (11) .

16. The projector (100) according to at least one of the previous claims,- wherein the LEDs (15) are at least partially embedded in the primary lenses (23) .

17. Projector (100) according to at least one of the previous claims, wherein- at least some optical elements (22) are embedded in a cover layer ( 31 ) ,- the cover layer (31) and the optical elements (22) embedded therein are formed of a polymer,- the cover layer (31) and the optical elements (22) embedded therein have different refractive indices.

18. Projector (100) according to at least one of the previous claims , wherein- at least some of the projection channels (21) are each assigned two different optoelectronic units (11) such that radiation from the at least two assigned optoelectronic units (11) is at least predominantly incident on the respective projection channel (21) .

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