Light guide device
By introducing symmetrically arranged sidewall reflectors and diffusers into the light guide device, the problem of insufficient light homogenization in a small space is solved, achieving efficient light homogenization and stability, reducing stray light, and improving the illumination uniformity of the emitting surface.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- MARQUARDT GMBH
- Filing Date
- 2025-03-10
- Publication Date
- 2026-07-17
AI Technical Summary
Existing light guide devices are insufficient in achieving uniform light and efficient coupling in small spaces, resulting in light spots and stray light on the light-emitting surface, which affects the lighting effect.
A light guide device is designed, comprising a light guide element and a sidewall reflector. By symmetrically arranging the surfaces of the sidewall reflectors in the longitudinal and height directions, stray light is redirected and uniformly distributed along a predetermined light path, thereby reducing stray light and forming a U-shaped accommodating space. The light guide element is then covered by a diffuser to achieve uniform illumination.
It achieves efficient light uniformity within a small installation space, reduces stray light, improves the uniform illumination effect of the light-emitting surface, and forms a shell structure on the sidewalls to stabilize the light guide device.
Smart Images
Figure CN122422701A_ABST
Abstract
Description
[0001] manual:
[0002] The present invention relates to a light guide device for uniform distribution of light or for uniformizing light that can be coupled in by a light source onto a light-emitting surface.
[0003] In principle, light guiding devices and light guiding devices for light homogenization are known in the prior art. However, it is advantageous to achieve light homogenization in the smallest possible space and homogenize as much coupled-in light as possible, so that the emitting surface can be illuminated as completely, uniformly and well as possible with as little coupled-in light as possible, and in particular, no individual light spot corresponding to the light source can be identified on the emitting surface.
[0004] For example, a trim element for a vehicle is known from DE 10 2023 127 543.7, wherein light coupled in from the rear is guided along a predetermined optical path from a rear light source to a light-emitting surface on the visible side via a light guide element having an inclined reflective surface, and is simultaneously homogenized along the optical path. The teachings of that document are incorporated herein by reference in their entirety.
[0005] However, this homogenization can be further optimized to achieve a smaller installation space required for homogenization and higher light output or higher homogenization efficiency.
[0006] Therefore, the present invention aims to overcome the above-mentioned disadvantages and provide a light guide device through which light coupled in by a light source can be efficiently homogenized in a small installation space to illuminate the light-emitting surface.
[0007] This task is solved by the combination of features described in claim 1 of the patent.
[0008] Therefore, according to the present invention, a light guide device is proposed for uniformly distributing light coupled in by a light source onto a light-emitting surface. This light guide device has a light guide element having a back coupling-in surface corresponding to the light source and a visible-side coupling-out surface corresponding to the light-emitting surface, the coupling-out surfaces being spaced apart relative to the coupling-in surface along a longitudinal axis in the longitudinal direction. The light guide element is preferably constructed identically to the light guide element according to DE 10 2023 127 543.7, wherein the light guide device proposed in this invention can be integrated into a decorative panel element proposed by DE 10 2023 127 543.7. The light guide element proposed in this invention is configured to guide light coupled into the light guide element along the coupling-in axis on the coupling-in surface in the longitudinal direction, and to couple out onto the light-emitting surface along a coupling-out axis offset from the coupling-in axis in the longitudinal direction on the coupling-out surface, such that the light from the coupling-in surface to the coupling-out surface follows a predetermined light path, along which the light is homogenized, i.e., distributed to uniformly illuminate the light-emitting surface. However, stray light may be generated during light incident or coupling, causing it to not immediately follow the optical path and to contribute little or no illumination to the emitting surface. To minimize stray light or redirect it onto the optical path, the light guide device is further provided with two sidewalls symmetrically positioned opposite each other with respect to the plane of symmetry separating the coupling-in surface and the coupling-out surface, defining a space between them along a transverse axis that restricts or encloses the light guide element in a width direction perpendicular to the longitudinal direction. Thus, the light guide element is restricted and abutted against these sidewalls in the width direction perpendicular to the longitudinal direction. For this purpose, a reflector surface or reflective surface is provided on each sidewall facing the plane of symmetry or towards the light guide element, specifically configured to reflect light or stray light incident from the light guide element. The sidewalls, on their respective inner surfaces towards the light guide element or towards the reflector surfaces enclosing the light guide element, follow a predetermined longitudinal orientation in the longitudinal direction; and a predetermined height orientation in the height direction perpendicular to both the longitudinal and width directions. Here, according to the present invention, the receiving space defined by the reflector surface begins longitudinally from the coupling-in surface or the end face of the light guide device belonging to the coupling-in surface, and widens symmetrically in the width direction, particularly towards the coupling-out surface or the end face of the opposite light guide device belonging to the coupling-out surface. Further, the receiving space defined by the reflector surface begins vertically from the back side of the light guide element, i.e., the base surface facing the back side, and widens symmetrically in the width direction, particularly towards the visible side of the light guide element, i.e., the top surface facing the visible side, particularly towards the visible side. Thus, the receiving space has a substantially U-shaped basic shape in both the cross-section perpendicular to the longitudinal direction and the longitudinal section perpendicular to the height direction.
[0009] By means of the predetermined longitudinal direction and predetermined height direction of the inner sidewall or the reflective surface, stray light incident on it in the width direction can be redirected back to the optical path or coupled out of the axis and guided to the emitting surface in a predetermined manner, so that the stray light also contributes to the uniform illumination of the emitting surface.
[0010] However, another advantage is that the sidewalls also function as a housing, allowing them to form part of the housing surrounding the light guide element, which in turn stabilizes the light guide device and any products that may contain it.
[0011] It needs to be clarified that the vertical axis, horizontal axis, and height axis, as well as the corresponding longitudinal direction, width direction, and height direction, are orthogonal to each other and constitute a spatial Cartesian coordinate system.
[0012] An advantageous variation of the light guide device specifies that the plane of symmetry is stretched by the height and longitudinal directions and perpendicular to the width direction. The coupling in and coupling out surfaces can be axially or mirror-symmetrical with respect to the plane of symmetry. Furthermore, the light guide element can also be axially or mirror-symmetrical with respect to the plane of symmetry.
[0013] The coupling-in surface is preferably offset towards the top surface relative to the base surface in the height direction, so that the light guide element has a recessed portion, preferably at the end side relative to the base surface, where the coupling-in surface is disposed. Furthermore, the coupling-out surface may be offset away from the base surface relative to the top surface in the height direction, so that the light guide element has a protrusion at the top surface where the coupling-out surface is disposed.
[0014] The sidewalls extend from the base surface toward the top surface in the height direction, but do not necessarily reach the top surface.
[0015] Particularly advantageous here is a variant in which the height of the sidewall and / or the reflector surface of the sidewall from the base surface corresponds to 60% to 90%, particularly 70% to 80%, and even more particularly 75% of the height of the light guide element from the base surface to the top surface, thereby maintaining a light-transmitting gap in the width direction between the visible side end face of the sidewall or the visible side end edge of the reflector surface and the top surface, through which stray light can pass and / or couple out, so that the stray light does not cause adverse illumination of the emitting surface.
[0016] Preferably, the light guide element extends beyond the sidewall through a gap in the width direction, or is flush with the sidewall or the outer surface of the sidewall in the width direction.
[0017] Preferably, the height orientation of the reflector surface from the base surface of the light guide element to the top surface of the light guide element follows a (first) radius in the first region, which widens the receiving space in the width direction, and this radius transitions smoothly to the (first) straight line in the immediately following second region, which maintains the width of the receiving space. Therefore, the (first) straight line preferably extends parallel to the plane of symmetry and transitions to the (first) radius as a tangent to the circle that defines the (first) radius.
[0018] The height direction determined by the (first) radius preferably corresponds to one-quarter to one-sixth, particularly one-fifth, of a circle with a radius equal to the height of the sidewall. The (first) straight line extends the height direction to the visible side end face of the sidewall, wherein a chamfer or bevel may be provided at the end of the (first) straight line, through which a reflective surface or height direction transitions to the end face of the corresponding sidewall.
[0019] The light guide element is preferably enclosed in the longitudinal direction by two end faces that are opposite to each other, preferably parallel to each other, and inclined to the coupling axis. These two end faces may also be referred to as reflective surfaces or reflector surfaces. The first end face is configured to guide light coupled in along the coupling axis onto a predetermined optical path along the longitudinal axis. The second end face is further configured to guide light from the predetermined optical path onto the coupling axis.
[0020] Furthermore, equally preferably, the longitudinal orientation of the reflector surface follows a (second) radius from one end face of the light guide element on the coupling-in surface, i.e., the first end face, to one end face of the light guide element on the coupling-out surface, i.e., the second end face, in the first region. This radius widens the receiving space in the width direction, and transitions without corners to the (second) straight line, which extends the width of the receiving space in the immediately following second region. It also applies to the (second) straight line that preferably extends parallel to the plane of symmetry and transitions to the (second) radius as a tangent to the circle defining the (second) radius.
[0021] The longitudinal direction determined by the (second) radius preferably corresponds to one-quarter to one-sixth, particularly one-fifth, of a circle with a radius equal to the length of the sidewall. The (second) straight line here extends the length direction to the second end face of the light guide element.
[0022] Preferably, the length of the sidewall and / or the reflector surface of the sidewall from the first end face corresponds to 60% to 90%, particularly 70% to 80%, and even more particularly 75% of the total length of the light guide element from the terminating edge of the first end face to the terminating edge of the second end face.
[0023] Furthermore, according to an advantageous improvement, the light guide device also has a closed wall portion that, together with the sidewalls, completely covers the light guide element while exposing the coupling-in surface and the coupling-out surface, and accordingly forms a housing around the light guide element with the sidewalls, wherein the coupling-in surface and the coupling-out surface remain exposed so that light can be coupled into the coupling-in surface and coupled out of the coupling-out surface.
[0024] Additionally, the light guide device preferably has a diffuser that covers the light guide element from the visible side and is disposed adjacent to the coupling surface, and preferably forms a light-emitting surface on its visible side, such that the light guide element is invisible through the diffuser.
[0025] Additionally or alternatively, the light guide device may also have a light source, which is disposed at the coupling surface when an air gap is formed, so that light can be coupled into the coupling surface through the air gap via the light source.
[0026] Provided it is technically feasible and not contradictory, the features disclosed above can be combined as needed.
[0027] Other advantageous embodiments of the invention are described in the dependent claims, or are described in more detail below together with the description of preferred embodiments of the invention, with reference to the accompanying drawings.
[0028] Figure 1 A perspective view of a decorative component with an integrated light guide device is shown;
[0029] Figure 2 A longitudinal perspective cross-sectional view of the optical guide device along the plane of symmetry is shown.
[0030] Figure 3 This shows a longitudinal cross-sectional view of the optical guide device along the plane of symmetry;
[0031] Figure 4 A cross-sectional view of the optical guide device perpendicular to the longitudinal axis is shown;
[0032] Figure 5 A longitudinal cross-sectional view of the optical guide device perpendicular to the high axis is shown.
[0033] The accompanying drawings are exemplary and schematic, illustrating various views of one embodiment variation, and thus the same reference numerals in each drawing denote the same functional and / or structural features. However, different drawings may also show views of different embodiment variations, and thus they may be considered independently of each other.
[0034] exist Figure 1The illustration shows a decorative panel element or functional component having an integrated light guide device 1, through which the space-constrained luminescent surface 3 on the visible side (shown in the illustration) should be illuminated. For this purpose, a light guide element 10 and sidewalls 20 are housed within the decorative component or functional element, both of which are covered by a diffuser 4 on the visible side.
[0035] Although only one light guide device 1 is shown here, multiple such light guide devices 1 can be arranged adjacently in the width direction B or along the corresponding transverse axis, and can also be connected to each other through their light guide elements 10. The directly adjacent sidewalls 20 of the light guide devices 1 arranged directly adjacently can also be integrally formed with each other. This is also true for the diffusers and enclosed walls of such light guide devices 1.
[0036] The basic structure of the optical guide device 1 is as follows: Figure 2 As can be seen, it shows a cross section through the light guide device 1 along the plane of symmetry S, which will be further explained below. Light can be coupled from the light source 2, such as an LED, into the light guide element 10 along the coupling axis E at the coupling surface 11. The light is deflected at the first inclined reflective surface or end face 15 of the light guide element 10 onto a predetermined light path P, along which the light is selectively scattered in the light guide element 10 for homogenization, and guided to the opposite second reflective surface or end face 16 in the longitudinal direction L, where the light is guided along the coupling axis A to the coupling surface 12, such that the light is coupled into the diffuser 4 at the coupling surface 12 and uniformly illuminates a spatially defined luminous surface 3, for example, 20 mm x 3 mm.
[0037] For this purpose, the light guide element 10 and the light source 2 are also separated by an air gap 5 with a height of H7 and a width of W5, wherein the height H7 and the width W5 are preferably selected such that the light emitted from the light source 2 is substantially completely distributed on the coupling surface 11.
[0038] It is further specified that the coupling-in surface 11 is offset in the height direction relative to the base surface 13 facing the back side of the light guide element 10 towards the top surface 14 facing the visible side, thereby forming a recess at the first end face 15. The coupling-out surface 12 is provided at the protrusion opposite to the top surface 14, and is correspondingly offset in the height direction H relative to the top surface 14. The recess and the protrusion, or their respective height offsets, are used to reduce stray light and improve efficiency, because more light can be coupled in at the coupling-in surface 11, and stray light portions can be shielded or filtered at the coupling-out surface 12.
[0039] exist Figure 2It can also be advantageously seen that the light guide element 10 is not only surrounded by the sidewall 20, but also surrounded on the back side by the closed wall portion 6 (having a thickness or height H4) configured as a substrate, surrounded on the visible side by the closed wall portion 43 extending in the gap defined by the protrusion, and surrounded on the end face by the respective closed wall portions 41, 42, wherein the sidewall 20 is integrally formed with the closed wall portions 41, 42, 43, and can be manufactured together, for example, by injection molding.
[0040] Similar to the sidewall 20, reflective surfaces toward the light guide element 10 can also be formed or provided through the closed wall portions 6, 41, 42, 43, and these reflective surfaces are formed as reflector surfaces 21 on the sidewall 20.
[0041] As shown in the figure, the sidewall 20 and the reflector surface 21 disposed or formed thereon and facing the light guide element 10 are axially or mirror-symmetrically opposite each other with respect to the plane of symmetry S, and define a receiving space between them that encloses the light guide element 10 in the width direction B perpendicular to the longitudinal direction L.
[0042] The reflector surface 21 follows a predetermined longitudinal orientation in the longitudinal direction L, which is axially or mirror-symmetric with respect to the plane of symmetry S, and follows a predetermined height orientation in the height direction H perpendicular to the longitudinal direction L and the width direction B, which is axially or mirror-symmetric with respect to the plane of symmetry S.
[0043] Through this longitudinal orientation, the accommodating space widens in the width direction B from the coupling in surface 11 or the corresponding first end face 15 along the longitudinal direction L to the coupling out surface 12 or the corresponding second end face 16, such as... Figure 5 It is particularly visible in the middle.
[0044] Through this height orientation, the accommodating space widens in the width direction B from the back base surface 13 of the light guide element 10 along the height direction H to the visible side top surface 14 of the light guide element 10, such as... Figure 4 It is particularly visible in the middle.
[0045] like Figure 4 and Figure 5 As shown, what is particularly advantageous for both the longitudinal and vertical orientations is that they each have two regions, where each orientation in the first region is formed by an arc defined by radii R1 and R2. Through this arc, the accommodating space widens in the width direction B, and this arc transitions to straight lines 31 and 32 tangent to the arc, which extend parallel to the plane of symmetry S while maintaining their width. Regarding the tangent 32 in the longitudinal orientation, as... Figure 5 As shown, it exemplarily has a length L9 and a width W2, through which light incident on the inclined end face 16 can be homogenized and uniformly guided onto the light-emitting surface 3.
[0046] exist Figure 4 Another particularly advantageous feature can also be seen in this variation. The variant shown specifies that the sidewall 20 extends from the base surface 13 toward the top surface 14, but its height H6 corresponds only to 75% of the height H2 of the light guide element 10 between the base surface 13 and the top surface 14. This creates gaps 23 between the end face 22 of the sidewall 20 and the top surface 14, allowing unusable stray light to couple out from the receiving space or the light guide element 10 through each gap, thus preventing incorrect illumination of the light-emitting surface 3, i.e., uneven illumination.
[0047] Especially Figure 5 The maximum longitudinal extension L10 of the light guide element 10 is also shown, wherein the light guide element 10 is widened from the initial width W4 at the inclined end face 15 to the width W2 by a radius R2 on the side facing the diffuser 4.
[0048] In addition, especially through Figures 3 to 5 This illustrates other advantageous height, width, and length ratios, which can be achieved through a single variation or different implementations. Therefore, it is preferable to specify:
[0049] • The height H6 of the sidewall 20 should be 75% of the height H2 of the light guide element 10 between the base surface 13 and the top surface 14.
[0050] • The gap between the end face 22 of the sidewall 20 and the top face 14, determined by the difference between height H2 and height H6, is chosen to allow light to pass through the gap in the width direction.
[0051] • The first radius R1 should be 1 / 5 of the full circle, where the midpoint of the height H2 of the sidewall 20 can be considered.
[0052] • Line 31 extends the direction of the first radius R1 to the end face 22 of the corresponding sidewall 20.
[0053] • The light source 2 is positioned between the coupling surface 11 and the base surface 13 with its side facing the light guide element 10, and thus offset, for example, by a height H3, into the housing formed at least partially by the sidewall 20.
[0054] • The length L6 of the sidewall 20 should be 75% of the length L7 of the optical guide device 1 in the longitudinal direction.
[0055] • The total height, i.e., the sum of the height H5 of the diffuser 4 and the height H1 from the base surface 13 to the visible side surface of the adjacent closed wall portion 43 in the height direction, is preferably a maximum of 10 mm.
[0056] • Angles A1 and A2 are preferably equal, and more preferably 135°.
[0057] • The closed wall portion 43, which preferably completely covers the visible side of the top surface 14, is configured to maximize the light distribution in the light guide element 10 and has a length L5 that is preferably 60% of the total length L7, wherein the gap formed due to the height offset of the coupling surface 12 relative to the top surface 14 is configured to allow the injection of material to manufacture the closed wall portion 43.
[0058] • The second radius R2 is preferably referenced to the length L11 and width W1 assigned to the coupled surface 11.
Claims
1. A light guide device (1) for uniformly distributing light coupled in from a light source (2) onto a light-emitting surface (3). It has a light guide element (10) having a back-side coupling-in surface (11) corresponding to the light source (2) and a visible-side coupling-out surface (12) corresponding to the light-emitting surface (3), the coupling-out surface being spaced apart from the coupling-in surface (11) in the longitudinal direction (L). in, The light guide element (10) is configured to guide light coupled into the light guide element (10) at the coupling-in surface (11) along the coupling-in axis (E) in the longitudinal direction (L), and to couple it out at the coupling-out surface (12) along the coupling-out axis (A) which deviates from the coupling-in axis (E) in the longitudinal direction (L) towards the light-emitting surface (3). The light guide device (1) also has two sidewalls (20) that are symmetrically opposite each other with respect to the plane of symmetry (S) that separates the coupling-in surface (11) and the coupling-out surface (12), and that define therebetween a receiving space for the light guide element (10) in a width direction (B) perpendicular to the longitudinal direction (L). The sidewalls (20) of the light guide element (10) each follow a predetermined longitudinal orientation in the longitudinal direction (L) relative to the respective reflector surfaces (21) that enclose the light guide element (10). Through this longitudinal orientation, the receiving space widens in the width direction (B) from the coupling-in surface (11) along the longitudinal direction (L) towards the coupling-out surface (12). Each reflector surface (21) follows a predetermined height direction in the height direction (H) perpendicular to the longitudinal direction (L) and the width direction (B). Through the height direction, the accommodating space widens from the back base surface (13) of the light guide element (10) along the height direction (H) to the visible side top surface (14) of the light guide element (10) in the width direction (B).
2. The light guide device according to claim 1, in, The plane of symmetry (S) is spanned by the height direction (H) and the longitudinal direction (L) and is perpendicular to the width direction (B), and / or Wherein, the coupling-in surface (11) and the coupling-out surface (12) are axially symmetric with respect to the symmetry plane (S), and / or The light guide element (10) is axially symmetrical with respect to the plane of symmetry (S).
3. The light guide device according to claim 1 or 2, in, The coupling surface (11) is offset in the height direction (H) relative to the base surface (13) toward the top surface (14), and / or The coupling surface (12) is offset in the height direction (H) relative to the top surface (14) in a direction away from the base surface (13).
4. The light guide device according to any one of the preceding claims, in, The sidewall (20) extends in the height direction (H) from the base surface (13) toward the top surface (14).
5. The light guide device according to any one of the preceding claims, in, The height (H6) of the sidewall (20) and / or the reflector surface (21) of the sidewall (20) from the base surface (13) corresponds to 60% to 90%, particularly 70% to 80%, and even more particularly 75% of the height (H2) of the light guide element (10) from the base surface (13) to the top surface (14), thereby maintaining a light-transmitting gap (23) in the width direction (B) between the visible side end face (22) of the sidewall (20) and the top surface (14).
6. The light guide device according to the preceding claim, in, The light guide element (10) extends beyond the sidewall (20) through the slit (23) in the width direction (B), or is flush with the sidewall (20) in the width direction (B).
7. The light guide device according to any one of the preceding claims, in, The height orientation of the reflector surface (21) from the base surface (13) of the light guide element (10) to the top surface (14) of the light guide element (10) follows a radius (R1) in the first region that widens the receiving space in the width direction (B), the radius transitioning to a straight line (31) without corners, the straight line extending the width of the receiving space in the immediately following second region.
8. The light guide device according to the preceding claim, in, The height direction determined by the radius (R1) corresponds to one-quarter to one-sixth, and especially one-fifth, of a circle whose radius is equal to the height (H6) of the sidewall (20). Furthermore, the straight line (31) extends the height direction to the visible side end face (22) of the sidewall (20).
9. The light guide device according to any one of the preceding claims, in, The light guide element (10) is closed in the longitudinal direction (L) by two opposing end faces (15, 16) that are inclined relative to the coupling axis (E). The first end face (15) is configured to guide light coupled in along the coupling axis (E) onto a predetermined optical path (P) along the longitudinal axis (L). Furthermore, the second end face (16) is configured to guide the light from the predetermined optical path (P) to the coupling axis (A).
10. The light guide device according to any one of the preceding claims, in, The longitudinal orientation of the reflector surface (21) from the first end face (15) of the light guide element (20) at the coupling in surface (11) to the second end face (16) of the light guide element (20) at the coupling out surface (11) follows a radius (R2) in the first region that widens the receiving space in the width direction (B), the radius transitioning without corners to a straight line (32), the straight line extending in the width of the receiving space in the immediately following second region.
11. The light guide device according to the preceding claim, in, The longitudinal orientation determined by the radius (R2) corresponds to one-quarter to one-sixth, particularly one-fifth, of a circle whose radius is equal to the length (L6) of the sidewall (20). Furthermore, the straight line (32) extends the length direction to the second end face (16) of the light guide element (10).
12. The light guide device according to any one of the preceding two claims, in, The length of the sidewall (20) and / or the reflector surface (21) of the sidewall (20) from the first end face corresponds to 60% to 90%, particularly 70% to 80%, and even more particularly 75% of the total length (L10) of the light guide element (10) from the terminating edge of the first end face (15) to the terminating edge of the second end face (16).
13. The light guide device according to any one of the preceding claims, It also has closed wall portions (6, 41, 42, 43), which, together with the sidewall (20), completely cover the light guide element (10) while exposing the coupling in surface (11) and the coupling out surface (12).
14. The light guide device according to any one of the preceding claims, It also has a diffuser (4), which is disposed adjacent to the coupling surface (12) and covers the light guide element (10) from the visible side. And / or also having the light source (2), which is disposed at the coupling surface (11) in such a way as to form an air gap (5) so that light can be coupled into the coupling surface (11) via the air gap (5) through the light source (2).