Projection device for generating dynamic projections

Abstract

1. A projection device (100) for generating dynamic projections, comprising: a unit (101) of a plurality of spatially separated light sources (103-1, ..., 103-n); a collimation optical system (105) for generating parallel beam paths coming from the light sources (103-1, 103-n); and a microlens array unit (107) arranged in the beam path of the collimation optical system (105), in which the focal length of a lens (109-1) on the illumination side (111-1) within the material is greater than the spacing of the lens (109-1) relative to a slide plane (113).

Description

[Technical Field]

[0001] The present invention relates to a projection device for generating a dynamic projection and to a projection method for generating a dynamic projection. [Background technology]

[0002] There are ways to sequentially illuminate different areas of the projection geometry using different projectors that are connected in series. In this case, the projection directions of the projectors must be precisely aligned with each other to ensure a seamless transition of image content. Nevertheless, when graphics content continues, brightness artifacts often occur at the transitions between projections. Multiple projectors require more space and lead to increased costs.

[0003] The document DE 102009024894 A1 relates to a projection display having a light source and regularly arranged optical channels. The optical channels have field lenses, to which an object structure to be imaged and a projection lens are respectively assigned. The distance of the projection lens to the assigned object structure corresponds to the focal length of the projection lens, while the distance of the object structure to be imaged to the assigned field lens is selected to enable Köhler illumination of the assigned projection lens. In this case, the individual projections are superimposed on the overall image. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] German Patent Application Publication No. 102009024894 Summary of the Invention [Means for solving the problem]

[0005] The projection device for generating a dynamic projection according to the present invention, comprising a unit of spatially separated light sources, a collimation lens for generating parallel beam paths coming from the light sources, and a microlens array unit arranged in the beam path of the collimation lens, wherein the focal length of the lens on the illumination side within the material is greater than the spacing of the lenses relative to the slide plane, allows the technical advantage that the projector can use the microlens array to irradiate image information in a positionally variable manner, thereby achieving a dynamic projection that goes beyond simply changing the overall brightness.

[0006] In an advantageous embodiment of the projection device, the light sources are arranged in a line or in a matrix, which allows a high dynamics in one or two directions.

[0007] In another advantageous embodiment of the projection device, the lens is designed to be all-round, which makes it possible to avoid scattered light.

[0008] In another advantageous embodiment of the projection device, the lenses are arranged in a square, rectangular or hexagonal pattern, which allows for a further reduction of scattered light.

[0009] In another advantageous embodiment of the projection device, the focal length of the lens on the illumination side is greater than the focal length of the lens on the projection side, which allows a reduction of light entering adjacent channels.

[0010] In another advantageous embodiment of the projection device, the microlens array unit comprises a microlens array having a support and a matrix of lenses, which allows for a simplified production of the microlens array.

[0011] In another advantageous embodiment of the projection device, the support and the lenses are formed in one piece, which allows for an even simpler production of the microlens array.

[0012] In another advantageous embodiment of the projection device, the microlens array unit has a first microlens array on the illumination side and a second microlens array on the projection side, which allows for separate channels to be realized.

[0013] In another advantageous embodiment of the projection device, the focal length of the lens on the illumination side corresponds to the sum of the thickness of the microlens array on the illumination side and the thickness of the microlens array on the projection side, which allows a larger acceptance angle of the illumination optics to be realized.

[0014] The projection method according to the present invention, which comprises illuminating a microlens array unit with spatially separated light sources, in which the focal length of the lenses on the illumination side within the material is greater than the spacing of the lenses relative to the slide plane, is useful for generating dynamic projections, achieving the same technical advantages as those achieved by microlens arrays.

[0015] The embodiments of the present invention will be described in detail with reference to the following drawings. [Brief explanation of the drawings]

[0016] [Figure 1] 1 shows a schematic diagram of a projection device having a microlens array. [Figure 2] 2 shows another schematic diagram of a projection device with a microlens array. DETAILED DESCRIPTION OF THE INVENTION

[0017] FIG. 1 shows a schematic diagram of a projection device 100 having a microlens array unit 107. The microlens unit 107 has two transparent microlens arrays 115-1 and 115-2, with a slide plane 113 disposed between them. The slide plane 113 stores image information suitable for projection. The microlens arrays 115-1 and 115-2 each have a matrix of lenses 109-1 and 109-2 arranged on respective supports 117-1 and 117-2. The projection device 100 is configured such that the positions of the light sources 103-1, ..., 103-n are roughly projected in angular space using the collimation optics 105, and individual regions of the light entrance surface are extracted from this light by the lens 109-1 on the illumination side 111-1.

[0018] The illumination light is split into individual channels by the microlens array 115-1. Directly adjacent to the lens 109-1, in the individual channels, respective micro-images are present in the slide plane 113. Due to their proximity to the lens 109-1, the micro-images are uniformly illuminated, similar to the illumination light at the position of the lens 109-1. The individual micro-images are projected from the lens 109-2 on the projection side 111-2 onto a three-dimensionally arranged projection geometry 119, for example in the form of a flat surface or road surface.

[0019] Because the projection device 100 has individual channels that project onto the projection geometry 119 from equivalent viewpoints, the respective microimages in the slide plane 113 have a strong similarity to one another. Generally, this involves a small displacement of the position of a microimage within the channel dimension compared to that within adjacent channels. The degree of difference in image information in the individual channels results from a typical spacing between individual channels on the order of about 1000 μm and a typical projection distance of 10 cm to 10 m.

[0020] According to the optical principles of integral photography, projected images overlap not only in the light field but also on the projection geometry. This allows for sharpness of projected details that resolve finer details than is possible with projection using a single channel. Furthermore, through the superposition of the integral equations of the individual channels, a geometry of maximum image sharpness can be constructed that precisely corresponds to the projection geometry 119. Similarly, the sum of the positions of maximum image sharpness of the integral photos at the observation of lens 109-1 is located on the geometry of the object arranged in three dimensions. In this regard, the three-dimensional position of the projection geometry 119 relative to the microlens array unit 107 is stored as part of the image construction.

[0021] The individual light sources 103-1, ..., 103-n positioned at different positions are projected by the collimation optics 105 from one or more lenses into different angular regions to illuminate the microlens array 115-1. In the microlens array 115-1, the lens 109-1 has a spacing to the slide plane 113 that corresponds at most to the focal length of the lens 109-1. By operating the individual light sources 103-1, ..., 103-n, the image information of the slide plane 113 is illuminated at different positions and projected onto the projection geometry 119.

[0022] Part of the light from one channel in the lens 109-2 on the projection side 111-2 can penetrate into another channel, resulting in so-called ghost images (inter-channel crosstalk). Therefore, it is advantageous to select the focal length of the lens 109 on the illumination side 111-1 to be somewhat larger than the thickness of the microlens array 115-1 on the illumination side 111-1. This minimizes light penetration into adjacent channels. The further the imaging plane of the light sources 103-1, ..., 103-n is from the slide plane 113, the less localized the illumination becomes. This allows for a soft-focus effect. The soft-focus effect, on the one hand, makes gaps between the light sources 103-1, ..., 103-n less visible in the image when they are spaced apart from one another, and, on the other hand, allows for less abrupt or continuous changes in the illumination of the image content when the light sources 103-1, ..., 103-n are dynamically switched.

[0023] The light sources 103-1, ..., 103-n may be formed by six light-emitting diodes, each rectangularly shaped and arranged in a straight line next to one another. Using collimation optics 105, the light-emitting diodes are imaged in angular space. By means of lens 109-1, the image of the light-emitting diodes appears in the slide plane 113.

[0024] In this example, the values ​​for the thickness of the microlens array 115-1 on the illumination side 111-1 and the focal length of the lens 109-1 on the illumination side 111-1 are the same as the thickness of the microlens array 115-2 on the projection side 111-2 and the focal length of the lens 109-2 on the projection side 111-2. The thickness of the microlens array 115-2 on the projection side 111-2 refers to the distance between the lens 109-2 on the projection side 111-2 and the slide plane 113. The thickness of the microlens array 115-1 on the illumination side 111-1 refers to the distance between the lens 109-1 on the illumination side 111-1 and the slide plane 113.

[0025] However, it may be advantageous to select the focal length of the lens 109-1 on the illumination side 111-1 to be greater than the focal length of the lens 109-2 on the projection side 111-2. When the focal length of the lens 109-2 on the projection side 111-2 substantially corresponds to the thickness of the microlens array 115-2 on the projection side 111-2, the focal length of the lens 109-1 on the illumination side 111-1 is greater than the thickness of the microlens array 115-2 on the projection side 111-2. In this way, less light reaches the adjacent channel. The closer the focal length of the lens 109-1 on the illumination side 111-1 is to the sum of the thickness of the microlens array 115-1 on the illumination side 111-1 and the thickness of the microlens array 115-2 on the projection side 111-2, the higher the acceptance angle of the illumination optical system and the less ghost images occur. The light sources 103-1, ..., 103-n are imaged into lens 109-2 on the projection side 111-2. The stronger the focus on the slide plane 113, the smaller the angular image of the light sources 103-1, ..., 103-n is used. This can be achieved by a larger collimation optics 105 or by smaller light sources 103-1, ..., 103-n.

[0026] By imaging the illumination light onto the slide plane 113, the light sources 103-1, ..., 103-n are not imaged as points, but rather are imaged to regions of microimages within the slide plane 113. However, because the microimages are slightly shifted relative to one another within the individual channels, their illumination is also slightly shifted relative to the image content. In this way, the illumination is blurred at the same position at other points of the image content on the projection geometry. In this case, every individual light source 103-1, ..., 103-n illuminates its assigned region within the microimage and therefore indirectly illuminates its appropriately assigned region on the projection geometry.

[0027] With projection device 100, projection is made possible by a microlens array unit 107 that can illuminate the projected image information differently from the slide plane in response to activated light sources 103-1, ..., 103-n. In this way, a dynamic projection can be achieved that goes beyond simply changing the overall brightness of the projection. This dynamic illumination can be achieved, for example, as a kind of illumination of different areas of a projected sequential turn signal in an automobile, but many other possible types are also possible.

[0028] It is advantageous to configure the lenses 109-1 of the illumination side 111-1 in a completely arranged, for example, square, rectangular or hexagonal configuration, to avoid scattered light that may occur with circular lenses 109-1 when light is incident on the microlens array 115-1 at various angles in the areas between the individual lenses 109-1, illuminating a microimage slightly more locally than the image of the light sources 103-1, ..., 103-n.

[0029] Furthermore, it is advantageous to configure the lenses 109-2 of the projection side 111-1 in a completely arranged, for example, square, rectangular or hexagonal configuration, to avoid scattered light that would otherwise exit between the lenses 109-2 and result in insufficient focusing on the projection geometry, which could lead to inter-channel crosstalk. The units of light sources 103-1, ..., 103-n may be provided, for example, by five light-emitting diodes positioned next to each other in one direction, or by a matrix of 10 x 10 light-emitting diodes.

[0030] 2 shows an exemplary unit of 3x6 light-emitting diodes 103-1, ... 103-n as light sources, rectangularly shaped and arranged in a matrix. The emitting light sources 103-1, ... 103-n are shown hatched not only in the plane of the light-emitting diodes but also in the plane of the projected image on the projection geometry. The image content of the microimage coming from the slide plane 113 is not shown. The soft focus effect due to defocusing of the light-emitting diodes on the microimage is also not shown.

[0031] These are imaged in angular space using the collimation optics 105. Through the lens 109-1, the image of the light-emitting diode appears near the slide plane 113 together with the micro-image. In this example, the thickness value of the micro-lens array 115-2 on the projection side 111-2 coincides with the focal length of the lens 109-2.

[0032] The thickness of the microlens array 115-1 on the illumination side 111-1 is greater than the thickness of the microlens array 115-2 on the projection side 111-2. The focal length of the lens 109-1 on the illumination side 111-1 is greater than the thickness of the microlens array 115-1 on the illumination side 111-1.

[0033] The present invention allows for variable projection in the form of locally variable illumination of image content on projection geometry 119, while at the same time reducing the further effort compared to conventional projectors with microlens arrays. This is achieved by selecting the thickness of microlens array 115-1 to be smaller than the focal length of lens 109-1 and by using multiple light sources 103-1, ..., 103-n.

[0034] The projection device 100 can realize dynamic welcome scenarios or security-related projections, for example, by switching on and off the projected zebra strips one after the other from one side to the other. Due to its dimensions, the projection device 100 is particularly suitable as a lighting fixture for light carpets in the automotive sector, as a projection display, as dynamic symbol projection in hotels or airplanes, as effect lighting, as guidance projection, or as danger zone projection in buildings.

[0035] All features described and illustrated in connection with individual embodiments of the invention may be provided in the subject matter according to the invention in various combinations, so that the advantageous effects of the various combinations are simultaneously realized.

[0036] All method steps may be performed by apparatus suitable for performing the respective method step. All functions performed by the embodied features may be method steps of the method.

Claims

1. a unit (101) of spatially separated light sources (103-1, ..., 103-n); a collimation optical system (105) for generating parallel beam paths coming from the light sources (103-1, 103-n); a microlens array unit (107) disposed in the beam path of the collimation lens (105), wherein the focal length of the lens (109-1) on the illumination side (111-1) within the material is greater than the distance of the lens (109-1) from the slide plane (113); A projection device (100) for generating dynamic projections, comprising:

2. 2. The projection device (100) of claim 1, wherein the light sources (103-1, . . . , 103-n) are arranged in a line or in a matrix.

3. The projection device (100) according to claim 1 or 2, wherein the lens (109-1) is configured as a full surface.

4. 4. The projection device (100) of claim 3, wherein the lenses (109-1) are arranged in a square, rectangular or hexagonal pattern.

5. Projection device (100) according to any one of claims 1 to 4, wherein the focal length of the lens (109-1) on the illumination side (111-1) is greater than the focal length of the lens (109-2) on the projection side (111-2).

6. 6. The projection device (100) according to claim 1, wherein the microlens array unit (107) comprises a microlens array (115-1) comprising a support (117-1) and a matrix of lenses (109-1, 109-2).

7. 7. The projection device (100) according to claim 6, wherein the support (117-1) and the lenses (109-1, 109-2) are integrally formed.

8. 8. The projection device (100) of claim 1, wherein the microlens array unit (107) has a first microlens array (115-1) on the illumination side (111-1) and a second microlens array (115-1) on the projection side (111-2).

9. 9. The projection device (100) according to claim 1, wherein the focal length of the lens (107-1) on the illumination side (111-1) corresponds to the sum of the thickness of the microlens array (115-1) on the illumination side (111-1) and the thickness of the microlens array (115-2) on the projection side (111-2).

10. illuminating, by a plurality of light sources (103-1, ..., 103-n), microlens array units in the spatially separated material, the focal lengths of the lenses (109-1) on the illumination side (111-1) of the microlens array units being greater than the spacing of the lenses (109-1) relative to the slide plane (113); A projection method for generating a dynamic projection having:

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