Display device with coated reflective surface for displaying information

Abstract

The invention relates to a display device (1) for displaying information, comprising an optical body (30) and a main display element (10) which is designed to emit light for displaying information and to couple the light into the optical body (30) in a first plane (31), the optical body (30) is designed to reflect the coupled light on a reflecting surface (36) arranged in a third plane (33) in order to display information for an observer (B) and to deflect the coupled light to a second plane (32), the reflecting surface (36) of the optical body (30) being provided with at least one coating (38) for reflecting the light.

Description

[0001] The invention relates to a display device with a coated reflective surface for displaying information, in particular information in a motor vehicle.

[0002] A variety of display devices based on various functional principles are known from the prior art.

[0003] It is also known to couple the light generated by a display screen or a display element into an adjacent optical body, where it is deflected so that it can be viewed by an observer.

[0004] Since the light is deflected in the optical body, the observer no longer directly views the display screen, but only the optical body designed to be aesthetically appealing, through which the light is directed or reflected in a targeted manner.

[0005] However, there is a problem that when light is deflected or reflected in the optical body, light is scattered or light escapes from the optical body on an unintended surface, or light coupled for information display cannot be completely deflected in a predetermined direction.

[0006] It is also possible that at certain viewing angles, the observer sees not light deflected from the optical body, but light escaping from the optical body at an imaginary surface of the optical body that is not used for display. Furthermore, this light or the image generated by it is not deflected as expected in the optical body, so that the image seen by the observer through the light is distorted or mirror-inverted, and in any case has a negative impact on the readability of the display device.

[0007] The object of the present invention is therefore to overcome the above-mentioned disadvantages and to provide a display device in which an observer, when observing an optical body, perceives images or information substantially completely in the intended manner.

[0008] This object is achieved by the combination of features described in patent claim 1 .

[0009] Therefore, according to the present invention, a display device for displaying information, in particular for displaying information in a motor vehicle, is proposed. The display device has an optical body and a main display element, which can be a display with backlighting or other suitable coupling sources. Here, the display device is constructed to emit light for information display or generally for image generation, and couple the light into the optical body on a first plane of the optical body, in particular on a coupling surface in the first plane. In addition, the optical body is also constructed to reflect the coupled light for displaying information to an observer on a reflection surface arranged in a third plane, and deflect it, that is, in particular reflect it to a second plane, wherein the second plane is inclined corresponding to the first plane. As a result, the observer can capture the light coupled from the main display element to the first plane and read the information by observing the second plane or the display surface mentioned below. Here, according to the present invention, it is provided that at least one coating is provided on the reflection surface of the optical body for reflecting light.

[0010] It is generally established that in conventional arrangements, light coupled into the optical body on a first plane is reflected too little on the reflective surface, which means that the image generated on the second plane or display surface is usually dark or too dark. Furthermore, unreflected light may leak out of the optical body on a third plane, where the reflective surface is located, and thus be perceived by an observer in an undesirable manner.

[0011] The reason why the light is not completely reflected is usually that the reflecting surface or the second plane on which it is located is at an angle of about 40° to 50° to the incident light coupled to the first plane, and depending on the material selected for the optical body, complete total reflection cannot be achieved. However, such an angle is necessary or at least advantageous for information display.

[0012] According to the invention, it is therefore generally proposed to provide an additional coating or layer in order to improve the reflection properties of the reflective surface.

[0013] According to an advantageous further development, it is provided that the coating has at least one layer made of metal, in particular of aluminum or silver. If the coating has multiple layers, it is preferably provided that at least one layer is formed of metal.

[0014] Furthermore, the reflective surface of the optical body for reflecting light can be coated with multiple layers, in particular alternating layers, to form a coating to form an optical resonator. The alternating layers or the resonator formed thereby are configured to shift the phase of the reflected light relative to the incident light by λ / 2 or a multiple of λ / 2.

[0015] At least a portion of the layer forming the optical resonator may be made of indium tin oxide (ITO).

[0016] The coating or at least one layer forming the coating is particularly advantageously vapor-deposited, so that correspondingly low layer thicknesses can thereby be achieved.

[0017] The optical body is preferably an optical crystal, ie, rigid. It is thus possible that the optical body or the optical crystal only needs to be embedded in the carrier in the region of the first plane, while the other surfaces can be substantially unoccupied.

[0018] For example, if the display device is integrated into a steering handle of a motor vehicle, one side of the optical body forming the first plane can be embedded in the steering rim or grip section of the steering handle, so that the optical body protrudes from the steering rim or grip section. Of course, the optical body can also be covered by design elements or functional elements, such as foils or the like, wherein these elements have no supporting or load-bearing function for the optical body.

[0019] The optical body has a coupling surface in a first plane, and light is coupled into the optical body on the coupling surface. In addition, the optical body has a display surface in a second plane in addition or alternatively, and light is projected onto the display surface to display information. The display surface may also be additionally provided with an anti-glare coating and / or an anti-reflection coating to improve the quality or contrast of the image visible on the display surface, thereby improving the display effect or readability on the display surface. In addition or alternatively, the optical body also has a reflective surface in a third plane, and light from the first plane is deflected to the second plane on the reflective surface, and wherein the third plane is arranged at an angle of 20° to 70°, particularly 40° to 50°, and further particularly 45° relative to the incident light from the first plane, i.e., extending along the main direction toward the third plane.

[0020] Furthermore, the display device further comprises an auxiliary display element, which is preferably arranged adjacent to the third plane and is used for emitting light to realize information display and coupling the light into the optical body.

[0021] Here, the auxiliary display element can be configured to couple light into the optical body orthogonally to the second plane or display surface and in particular on the reflective surface. For this purpose, the coating provided on the reflective surface can be configured to be light-transmissive on one side.

[0022] Therefore, the display provided on the display surface can be provided jointly by a main display element and an auxiliary display element, wherein images and / or information generated by the first display element and the second display element by respectively coupled light for generating the display can be arranged adjacent to each other on the display surface and / or can at least partially overlap with each other.

[0023] Furthermore, it may be provided that a pointing element is connected upstream of the optical body, the pointing element being constructed to guide the light emitted by the main display element into a main direction before it is coupled into the optical body, thereby eliminating or reducing a scattered light component of the coupled light, or aligning the scattered light component into the main direction.

[0024] Here, the main direction is particularly understood to be a direction orthogonal to the first plane. Alternatively, the main direction can also be defined as a direction reflected orthogonally to the second plane on a third plane, and the third plane will be described in detail below.

[0025] By directing or aligning the light, the illumination angle in the main direction is limited so that the light propagating in the main direction can be deflected as desired onto the optical body. Thus, when an observer looks directly at the main display element, the light is not perceived or at least is perceived to be reduced.

[0026] Here, an advantageous further development provides that the pointing element is an at least single-layer film, in particular made of plastic. Furthermore, it can also be an at least single-layer film made of PMMA.

[0027] Furthermore, the pointing element is configured as an optical structure for collimating light, which limits the optical illumination angle of the light emitted by the main display element in a main direction.

[0028] Here, the optical structure is a linear lens and / or prism structure and / or a grating or a thin sheet generated by a laser in particular, which can absorb light outside the main direction and / or deflect the light in the main direction. Since the scattered light component in the light is deflected in the main direction, the brightness of the light in the main direction is also increased.

[0029] Furthermore, the directing element is multi-layered, wherein the layer with the optical structure is arranged between two transparent layers, which are in particular covered by a protective layer on the respective side facing away from the optical structure.

[0030] For example, the layer with the optical structure can be a laminated layer and thus have a grating. The lamellae or gratings can be formed in particular from acrylic resin and / or carbon black.

[0031] The two transparent layers, between which the layer with the optical structure is arranged, can be formed, for example, from polycarbonate.

[0032] The protective layer covering the transparent layer can be matte or glossy and have or be formed with abrasion protection.

[0033] In particular, the thickness of the transparent layer is between 100µm (micrometers) and 150µm, and preferably 125µm. Further preferably, the thickness of the laminating layer is between 100µm and 300µm, and in particular 200µm.

[0034] The distance between the individual lamellae or gratings extending parallel to one another in the laminate layer is preferably between 50 and 100 μm, in particular 72 μm, wherein the thickness of the lamellae themselves is, for example, less than 5 μm and further in particular 1 μm.

[0035] The thickness of other layers, such as the connecting layer between the lamination layer and the transparent layer and the protective layer, can be very small and can therefore be neglected.

[0036] The total thickness of the pointing element, ie the extension in the main direction, is preferably less than 1 mm (millimetre) and in particular lies in the range of 0.4 to 0.7 mm, in particular 0.53 mm.

[0037] The pointing element can be arranged between the main display element and the optical body. Alternatively, the main display element can have a backlight, ie a background light, and also have a display screen and a pointing element, wherein the pointing element is arranged behind the backlight, before or behind the display screen.

[0038] As long as it is technically feasible and not contradictory, the features disclosed above can be combined as needed.

[0039] Further advantageous embodiments of the invention are described in the dependent claims or are explained in more detail below together with the description of the preferred embodiments of the invention with reference to the accompanying drawings.

[0040] Figure 1 A steering handle of a motor vehicle is shown with two integrated display devices;

[0041] Figure 2 A conventional display device is shown;

[0042] Figure 3 A variant of the display device according to the invention is shown;

[0043] Figure 4 A second variant of the display device according to the invention is shown.

[0044] The accompanying drawings are schematic examples. The same reference numerals in the accompanying drawings represent the same functions and / or structural features.

[0045] For clarity, Figure 1 A steering handle 2 of a motor vehicle is depicted, in which two display devices 1 are integrated. Figure 2 , Figure 3 and Figure 4 The described construction has the main display element 10 embedded in a circumferential steering rim 50 of the steering handle 2 , wherein the optical body 30 projects radially inwards from the steering rim and is substantially free of further supporting elements.

[0046] To illustrate this problem, Figure 2 A display device 1 is shown without a coating 38 according to the invention. The main display element 10 couples light or an image generated therefrom on a first plane 31 of an optical body or optical crystal 30 into the optical body or optical crystal, wherein the first light L1 coupled in along the main direction A is only partially reflected on the reflection surface 36 in the third plane 33. Due to the absence of total reflection at the third plane 33, another part of the coupled light escapes from the optical crystal 30 as second light L2, which can be perceived by the observer B in an unspecified manner.

[0047] Since the second light L2 may not be reflected or guided or may be reflected or guided incorrectly in the optical crystal 30 and emerge from the optical body 30 in an unspecified plane, the observer B may see the second light L2 at certain positions, thereby perceiving a distorted and unintended image.

[0048] Since the light L1 for information display is reflected exactly once in the optical crystal 30, especially on the third plane, a reflection is generated, for example Figure 2The image captured by observer B is upside down.

[0049] To avoid such erroneous images, Figure 3 As shown, a coating 38 of the optical body 30 or the optical crystal 30 is provided on the third plane 33. In this example, the coating 38 is formed of a vaporized metal, thereby improving the reflection of the light L1 incident on the reflection surface 36 from the main direction A and substantially completely reflecting it. This not only prevents the light from escaping on a surface or plane not specified therefor, but also improves the brightness of the light irradiated on the second plane 32 or the display surface 35.

[0050] The light or the image generated thereby is correspondingly coupled into the optical crystal 30 by the main display element 10 on the first plane 31 or on the coupling surface 34 arranged on the first plane 31, is substantially completely reflected on the third plane 33 or on the reflection surface 36 arranged at the third plane, and is thereby deflected toward the second plane 32 or is deflected onto the display surface 35 arranged at the second plane, so that the observer B can correctly read and perceive the image generated by the light L1 or the information generated by the light L1.

[0051] In addition, a covering portion 51 may be provided that covers the optical crystal 30 starting from the main display element 10, so that the edge of the optical crystal 30 formed at the intersection of the first plane 31 and the second plane 32, and preferably also the main display element 10, will not be seen by the observer B.

[0052] exist Figure 4 Shown in Figure 3 A variant in which an additional coating 37 is provided on the second plane 32 and a directing element 40 connected upstream of the first plane 31, by which light originally coupled into the optical body 30 outside the main direction A or obliquely to the main direction A is deflected or absorbed in the main direction A. Here, an anti-glare and / or anti-reflection coating, in particular completely covering the display surface 35, can also be provided as coating 37 in order to improve the quality or contrast of the image.

[0053] In order to supplement the display, auxiliary display elements 20, 21 can also be provided, which can be arranged alternately or together on the side of the optical crystal 30 opposite to the second plane 32. They can couple light L3, L4 orthogonal to the main direction or the second plane 32 into the optical crystal 30, thereby generating an image on the display surface 35, which is superimposed on the image generated by the main display element 10 on the display surface 35 and / or supplements it.

[0054] Therefore, the light L4 coupled from the auxiliary display element 20 is arranged to expand the image generated by the main display element 10, making the image generated for the observer B larger.

[0055] On the other hand, the light L3 coupled to the auxiliary display element 21 is arranged to be superimposed on the image generated by the main display element 10, so that the superimposed images together form an information display for the observer.

Claims

1. A display device (1) for displaying information, comprising an optical body (30) and a main display element (10), wherein the main display element is configured to emit light for displaying information and couple light into the optical body (30) in a first plane (31), wherein: The optical body (30) is configured to reflect the coupled light on a reflection surface (36) arranged in a third plane (33) so as to display information for an observer (B), and to deflect the coupled light to a second plane (32). It is characterized in that The reflective surface (36) of the optical body (30) is provided with at least one coating (38) for reflecting the light.

2. The display device according to claim 1, in, The coating (38) is or includes at least one metal layer.

3. The display device according to claim 1 or 2, The reflective surface (36) of the optical body (30) is coated with a plurality of layers for reflecting the light and forming the coating (38), wherein the plurality of layers form an optical resonator configured to shift the phase of the reflected light relative to the incident light by λ / 2 or a multiple of λ / 2.

4. Display device according to the preceding claim, wherein At least a portion of the layer forming the optical resonator is formed of indium tin oxide.

5. A display device according to any one of the preceding claims, wherein: The coating (38) is vapor-deposited.

6. A display device according to any one of the preceding claims, wherein: The optical body (30) is an optical crystal.

7. A display device according to any one of the preceding claims, in, The optical body (30) has a coupling surface (34) in the first plane (31), the light is coupled into the optical body (30) on the coupling surface, and / or wherein: The optical body (30) has a display surface (35) in the second plane (32), the light is projected onto the display surface to display information, and / or wherein light from the first plane (31) is deflected on the third plane (33) to the second plane (32), and wherein the third plane (33) is arranged at an angle of 20° to 70° relative to the incident light from the first plane (31).

8. The display device according to any of the preceding claims, further comprising an auxiliary display element (20, 21) which is designed to emit light for information display and couple it into the optical body (30).

9. Display device according to the two preceding claims, wherein: The auxiliary display elements (20, 21) are configured to couple light into the optical body (30) in a manner orthogonal to the display surface (35).

10. A display device according to any one of the preceding claims, wherein: A pointing element (40) is connected upstream of the optical body (30), the pointing element being configured to guide light emitted from the main display element (10) into a main direction (A) before the light is coupled into the optical body (30).

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