Light emitting device with lens array

Abstract

A light emitting device (1) comprising: an array of light emitting elements (2) configured to emit light in operation in a main emission direction (M); and a lens array (3) arranged to cover at least a portion of the light emitting element array (2), where each lens of the lens array (3) is arranged to cover a light emitting element of the light emitting element array (2), where each lens of the lens array (3) is a free-form lens, and where the lens array (3) comprises a plurality of first lenses (31) and a plurality of second lenses (32), the plurality of first lenses (31) are configured to guide light emitted by the light emitting elements to a first direction (D1) different from the main emission direction (M), and the plurality of second lenses (32) are configured to guide light emitted by the light emitting elements to a second direction (D2) different from the main emission direction (M), the first direction (D1) being different from the second direction (D2).

Description

Technical Field

[0001] This invention relates to a light-emitting device comprising: an array of light-emitting elements configured to emit light in a main emission direction during operation; and a lens array arranged to cover at least a portion of the array of light-emitting elements, wherein each lens of the lens array is arranged to cover a light-emitting element of the array of light-emitting elements. The invention also relates to luminaires or lamps including such a light-emitting device.

[0002] As used here, the term "2D color gradient" is intended to refer to a color gradient that exists simultaneously in two different directions when viewed on a target surface. Background Technology

[0003] With the introduction of pixelated lighting fixtures (such as hue gradient signals), consumers are now able to display gradient light patterns, for example, on walls. However, these gradients are defined as 1D, meaning that only the gradient exists in the light pattern in one direction, i.e., in the same direction as the main orientation of the LED strip.

[0004] US2019 / 326350A1 discloses a source-sensitive optics device that uses a reconfigurable on-board (CoB) light-emitting diode (LED) array as a light source. The reconfigurable CoB LED array includes a predetermined number of LEDs, configurable for various lighting conditions. The reconfigurable CoB LED array can be multiple CoB LED arrays configured for use with the source-sensitive optics. The source-sensitive optics includes a surface shape responsive to the reconfigurable CoB LED array. The source-sensitive optics is configured to provide beam profile and radiation pattern differences based on the CoB LED array configuration configured by the reconfigurable CoB LEDs. Due to proximity and surface shape geometry, each configurable CoB LED array configuration radiates a different beam pattern through its surface shape.

[0005] In current pixelated LED strips, smooth color gradients are possible by altering the LED spectrum along the strip's main axis, such as... Figure 1 As shown. However, another color change or gradient cannot be made, for example, in a direction orthogonal to the smooth color gradient.

[0006] Therefore, it is desirable to provide a light-emitting device that can simultaneously generate different color gradients in at least two different directions when viewed on a target surface such as a wall or ceiling. Summary of the Invention

[0007] The purpose of this invention is to overcome this problem and to provide a light-emitting device that, when viewed on a target surface such as a wall or ceiling, can simultaneously generate different color gradients in at least two mutually different directions.

[0008] According to a first aspect of the invention, this and other objectives are achieved by a light-emitting device comprising: an array of light-emitting elements configured to emit light in a main emission direction during operation; and a lens array arranged to cover at least a portion of the array of light-emitting elements, wherein each lens of the lens array is arranged to cover the light-emitting elements of the array of light-emitting elements, and wherein each lens of the lens array is a freeform lens. Furthermore, the lens array includes a plurality of first lenses and a plurality of second lenses, the plurality of first lenses being configured to direct light emitted by the light-emitting elements in a first direction different from the main emission direction, and the plurality of second lenses being configured to direct light emitted by the light-emitting elements in a second direction different from the main emission direction, wherein the first direction is different from the second direction.

[0009] Thus, and particularly by providing a lens array comprising a plurality of first lenses and a plurality of second lenses, wherein the plurality of first lenses are configured such that light emitted by the light-emitting element is directed in a first direction different from the main emission direction, and the plurality of second lenses are configured such that light emitted by the light-emitting element is directed in a second direction different from the main emission direction, wherein the first direction is different from the second direction, a light-emitting device is provided that can simultaneously generate two different color gradients when viewed on a target surface such as a wall or ceiling.

[0010] In particular, this light-emitting device can use a 1D or 2D array of light-emitting elements to generate light output with a 2D color gradient. Typically, in use, the target surface is located within a distance of 0.5m to 1m from the light-emitting device.

[0011] Lenses in multiple first lenses and lenses in multiple second lenses can be arranged alternately in a lens array.

[0012] Therefore, a particularly well-defined color gradient can be obtained.

[0013] The lenses of multiple first lenses and multiple second lenses may have different surface profiles.

[0014] In addition to being able to generate different color gradients in a particularly simple way, these distinct surface profiles offer a particularly simple way to change or customize color gradients by selecting specific predefined surface profiles.

[0015] The plurality of first lenses may be freeform lenses configured to collimate the light emitted by the light-emitting element, and the plurality of second lenses may be freeform lenses configured to include a peanut shape.

[0016] It has been shown that providing such freeform lenses is particularly suitable for providing light output with well-defined 2D color gradients.

[0017] Multiple second lenses can be configured to guide the main portion of the light emitted by the light-emitting element at a beam angle between 40 and 65 degrees relative to the main emission direction.

[0018] Multiple first lenses can be configured to provide a first beam angle by light emitted from a light-emitting element, and multiple second lenses can be configured to provide a second beam angle by light emitted from a light-emitting element, wherein the first beam angle is smaller than the second beam angle.

[0019] The first beam angle may be at least 2×10 degrees smaller than the second beam angle, or at least 2×15 degrees, or at least 2×20 degrees.

[0020] The first beam angle can be 2×45 degrees, 2×50 degrees, or 2×55 degrees, and the second beam angle can be 2×60 degrees, 2×65 degrees, or 2×70 degrees.

[0021] The values ​​of these individual beam angles and / or the relationships between them have shown to be particularly suitable for producing light output with well-defined 2D color gradients in typical use cases, where the target surface is located within 0.5m to 1m of the light-emitting device.

[0022] The light emitted by the light-emitting elements of the light-emitting element array can include a variable color spectrum.

[0023] Therefore, the 2D color gradient of the light output can be controlled by changing the color spectrum of the light emitted by the light-emitting element. This can be done before, during, and after the manufacture of the light-emitting device, for example, at the end user's location and under installation conditions.

[0024] The light emitted by a light-emitting element covered by multiple first lenses may have a first color spectrum, and the light emitted by a light-emitting element covered by multiple second lenses may have a second color spectrum, and the first color spectrum is different from the second color spectrum.

[0025] The first chromatogram may differ from the second chromatogram, for example, in terms of color, brightness, or a combination thereof. The difference between the first and second chromatograms can be measured by the amount of change E or... It is a standard measurement that quantifies the difference between two colors appearing on a screen or target surface. The level is the difference between the displayed color of the input content and the original color standard. Lower... Indicates a smaller difference, while a higher difference indicates a larger difference. The horizontal line indicates a larger difference. Values ​​are represented on a scale from 0 (no difference) to 100 (representing exactly opposite colors, such as black and white or red and green). Therefore, in the current case, The difference between the first and second chromatograms is quantified as the difference that appears on the target surface.

[0026] This allows for the creation of clearly defined color gradients in two directions, for example... Figure 5 and Figure 7 As shown.

[0027] The light-emitting device may also include a controller configured to individually control the spectrum of light emitted by the light-emitting elements of the light-emitting element array.

[0028] Therefore, even after the light-emitting device has been manufactured, such as at the end user's location and under installation conditions, the 2D color gradient of the light output can be controlled.

[0029] The light-emitting element array and lens array can be arranged on the substrate.

[0030] An array of light-emitting elements can form an LED strip.

[0031] An array of light-emitting elements can be a two-dimensional array of light-emitting elements.

[0032] The light-emitting device may also include a diffuser plate arranged above the array of light-emitting elements.

[0033] The light-emitting device may also include a housing in which an array of light-emitting elements and an array of lenses are arranged.

[0034] Therefore, it effectively protects the light-emitting elements and lens array from external influences, such as dust.

[0035] The present invention also relates to a lamp comprising at least one light-emitting device according to any one of the preceding claims.

[0036] It should be noted that the present invention relates to all possible combinations of the features described in the claims. Attached Figure Description

[0037] This and other aspects of the invention will now be described in more detail with reference to the accompanying drawings, which illustrate embodiments of the invention.

[0038] Figure 1 The image shows the light pattern of a prior art light-emitting device as seen on the target surface.

[0039] Figure 2 A perspective view of the light-emitting device according to the present invention is shown.

[0040] Figure 3 It shows that according to Figure 2 A perspective view of an enlarged cross-section of a light-emitting device.

[0041] Figure 4 It shows in Figure 3 According to the plane IV shown Figure 2 A cross-sectional view of the light-emitting device.

[0042] Figure 5 The light pattern of the light-emitting device according to the invention as seen on the target surface is shown.

[0043] Figure 6 The diagram shows a simulation of the illuminance and color of light emitted by the light-emitting device according to the invention, as seen on a target surface, and demonstrates that a uniform color band can be produced using the light-emitting device according to the invention.

[0044] Figure 7 The diagram illustrates the illuminance and color of light emitted by the light-emitting device according to the invention as seen on a target surface, demonstrating that multiple vertical and horizontal gradients can be created using the light-emitting device according to the invention.

[0045] Figure 8 A schematic cross-sectional view of a lamp including a light-emitting device according to the present invention is shown.

[0046] As shown in the figures, the dimensions of layers and regions are exaggerated for illustrative purposes; therefore, these dimensions are provided to illustrate the general structure of embodiments of the invention. The same reference numerals consistently denote the same elements. Detailed Implementation

[0047] The invention will now be described more fully below with reference to the accompanying drawings, in which presently preferred embodiments of the invention are illustrated. However, the invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided for thoroughness and completeness and to fully convey the scope of the invention to those skilled in the art.

[0048] refer to Figures 2 to 4 An embodiment of the light-emitting device 1 according to the present invention will now be described. The light-emitting device 1 generally includes an array of light-emitting elements 2 and a lens array 3.

[0049] The light-emitting element array 2 is configured to emit light in the main emission direction M during operation, see [reference]. Figure 4 The light-emitting elements 21 and 22 of the light-emitting element array 2 can be configured to emit light with a variable color spectrum. The light-emitting element array 2 can be as follows: Figure 1The diagram shows a one-dimensional (1D) array. Alternatively, the light-emitting element array 2 can be a two-dimensional (2D) array. In the former case, the light-emitting element array 2 can form an LED strip. In the latter case, any size of the array is feasible in principle.

[0050] The light-emitting device 1 is configured to provide light output during operation. The light output of the light-emitting device 1 is a combination of the light emitted by all the light-emitting elements of the light-emitting element array 2.

[0051] The lens array 3 is arranged to cover at least a portion of the light-emitting element array 2. Each lens of the lens array 3 is arranged to cover the light-emitting elements of the light-emitting element array 2. Each lens of the lens array 3 is a freeform surface lens.

[0052] Lens array 3 includes a plurality of first lenses 31, which are configured to direct light emitted by the light-emitting element 2 covered by the lenses 31 in a first direction D1. See [link to related document]. Figure 3 and Figure 4 The first direction D1 is different from the main emission direction M. The lenses of the plurality of first lenses 31 include a first surface profile 33, see [link to documentation]. Figure 4 The plurality of first lenses 31 may be freeform lenses, configured to collimate the light emitted by the light-emitting element 2 covered by the lenses among the plurality of first lenses 31. The plurality of first lenses 31 are configured to provide a first beam angle A1 for the light emitted by the light-emitting element, see [reference needed]. Figure 4 The first beam angle A1 can be 2×45 degrees, 2×50 degrees, or 2×55 degrees.

[0053] Some of the light-emitting elements 21 in the light-emitting element array 2 are covered by lenses in a plurality of first lenses 31. The light emitted by the light-emitting elements 21 covered by the plurality of first lenses 31 can have a first color spectrum.

[0054] The lens array 3 also includes a plurality of second lenses 32, which are configured to direct light emitted by the light-emitting element 2 covered by the lenses 32 in a second direction D2. See [link to related documentation]. Figure 3 and Figure 4 The second direction D2 differs from the main emission direction M. Furthermore, the second direction D2 differs from the first direction D1. The lenses of the plurality of second lenses 32 include a second surface profile 34, see [link to documentation]. Figure 4 The second surface profile 34 differs from the first surface profile 33. The plurality of second lenses 32 may be freeform lenses configured to include a peanut shape. The plurality of second lenses are configured to guide the main portion of the light emitted by the light-emitting element at a second beam angle A2, see [reference needed]. Figure 4 The second beam angle A2 relative to the main emission direction M can be between 40 degrees and 65 degrees. The second beam angle A2 can be 2×60 degrees, 2×65 degrees, or 2×70 degrees.

[0055] Some of the light-emitting elements 22 in the light-emitting element array 2 are covered by lenses in a plurality of second lenses 32. The light emitted by the light-emitting elements 22 covered by the plurality of second lenses 32 can have a second color spectrum. The second color spectrum is different from the first color spectrum.

[0056] The second beam angle A2 is greater than the first beam angle A1. In other words, the first beam angle A1 is smaller than the second beam angle A2. For example, the first beam angle A1 is at least 2 × 10 degrees, or at least 2 × 15 degrees, or at least 2 × 20 degrees smaller than the second beam angle A2.

[0057] The lenses of multiple first lenses 31 and multiple second lenses 32, such as Figure 3 The lenses are arranged alternately in lens array 3 as shown.

[0058] For details, please refer to the following: Figure 2 The light-emitting device 1 may optionally include a controller 7. The controller 7 is configured to individually control the light-emitting elements of the light-emitting element array 2, and in particular to individually control the spectrum of light emitted by the light-emitting elements of the light-emitting element array 2.

[0059] For details, please refer to the following: Figure 3 and Figure 4 The light-emitting element array 2 and lens array 3 may optionally be arranged on the substrate 4. The substrate 4 may be, for example, a printed circuit board. The substrate 4 may include wires configured to supply power to the light-emitting element 2. The substrate 4 may also include connecting elements configured to connect the wires to an electrical energy source such as mains power.

[0060] For details, please refer to the following: Figure 3 and Figure 4 The light-emitting device 1 may optionally include a diffuser plate 6. The diffuser plate 6 is disposed above the light-emitting element array 2. The diffuser plate 6 may be disposed at the light-emitting surface of the light-emitting device 1 or form the light-emitting surface of the light-emitting device 1. The diffuser plate 6 may include one or more of a light-emission coupling structure and a diffraction structure.

[0061] For details, please refer to the following: Figure 2 and Figure 3 The light-emitting device 1 may optionally include a housing 5, in which an array of light-emitting elements 2 and a lens array 3 are arranged. For example... Figure 2 As shown, the housing 5 may include a bottom surface 51, a top surface 52, and a circumferential sidewall 53 connecting the bottom surface 51 and the top surface 52. The inner surface 54 of the circumferential sidewall 53 facing the light-emitting element array 2 (see...) Figure 3The substrate 4 may be provided with a reflective layer or coating or made of a reflective material. In this configuration, the substrate 4 may also be arranged within the housing 5. Alternatively, the substrate 4 may form the bottom surface 51 of the housing 5. In this configuration, the diffuser plate 6 may be arranged at or form the upper surface 52 of the housing 5.

[0062] Now go to Figure 5 The diagram illustrates the light pattern of the light-emitting device 1 according to the invention as seen on a target surface such as a wall or ceiling. In this example, the first type of lens 31 of the lens array 3 is a freeform lens that collimates the light from the light-emitting element 21 in a straight direction to obtain a beam angle A1 of 2 × 50 degrees. The second type of lens 32 of the lens array 3 is a freeform lens with a peanut shape, which is configured to collimate the light from the light-emitting element 22 in an outward direction to obtain a beam angle A2 of 2 × 65 degrees, wherein most of the light is guided within a beam angle A2 of 40 to 65 degrees. By placing these lenses 31 and 32 in an alternating order on the light-emitting elements of the light-emitting element array 2, and by changing the color spectrum of the light emitted by the light-emitting elements 21 and 22 respectively, such as... Figure 5 As shown, 2D color gradients, namely color gradients G1 and G2, can be generated in two different, orthogonal directions.

[0063] Figure 6 The diagram illustrates a simulation of the illuminance and color of light emitted by the light-emitting device 1 according to the present invention, as shown above in conjunction with... Figure 5 As described, as seen on the surface of the target. Figure 6 A uniform color band can be produced using the light-emitting device 1 according to the invention. For example, color gradients are introduced into the light emitted by light-emitting elements 21 and 22 under two different types of lenses, such as green to red for light emitted by light-emitting element 22 under a second type of lens 32, and blue to green for light emitted by light-emitting element 21 under a first type of lens 31. In this way, a 2D color variation can be obtained. Thus, a light-emitting device 1 for use as a uniform color band is provided.

[0064] Figure 7 The diagram illustrates a simulation of the illuminance and color of light emitted by the light-emitting device 1 according to the present invention, as shown above in conjunction with... Figure 5 As described, as seen on the surface of the target. Figure 7 It is shown that multiple vertical and horizontal gradients can also be obtained using the light-emitting device 1 according to the invention (see Figure 5 (G1 and G2 in the original text). Therefore, we obtain 2D color gradients, that is, color gradients G1 and G2 in two different, orthogonal directions respectively.

[0065] It should be noted that Figure 6 and Figure 7 It is a black-and-white reproduction of the actual panchromatic result. For example, in Figure 7 In reality, the color gradient from top to bottom is from green through cyan to blue.

[0066] at last, Figure 8 An exemplary luminaire or lamp 12 including a light-emitting device 1 according to any embodiment of the invention is shown. In the illustrated embodiment, the light-emitting device 1 may be configured or formed as a substantially straight LED filament. In other embodiments, the light-emitting device 1 of such a lamp may be an LED filament having other shapes, such as, but not limited to, spiral, helical, zigzag, twisted, flat, and combinations thereof. In this embodiment, the light-emitting device 1 does not include any housing 5 or diffuser plate 6.

[0067] The lamp 12 also includes a driver or controller 17 configured to control the light-emitting element array 2 of the light-emitting device 1. The controller 17 is configured to supply power to the light-emitting element array 2 via the circuitry of the light-emitting device 1. The controller 17 can also be configured to control at least one of the CCT (Central Transmission Coefficient) and CRI (Central Resonance Coefficient) of the light emitted by the light-emitting device. The controller 17 can also be configured to control other parameters related to the light-emitting element array 2 and the light emitted by the light-emitting device.

[0068] The lamp 12 also includes a housing 13 that at least partially encloses at least one light-emitting device 1. The lamp 12 also includes a cap 14. (As...) Figure 8 As shown, the controller 17 is arranged within the housing 13. When the cap 14 is included, the controller 17 can also be arranged inside the cap 14, making it visually concealed. The lamp 12 also includes threads 15 for connecting to a socket and terminals 16 for connecting to an electrical source.

[0069] The cover 13 of the lamp 12 may also, and optionally, be provided with a coating 18 covering at least a portion of the cover 13, such as a reflective coating or a diffuse coating.

[0070] Notice, Figure 8 The luminaire or lamp 12 shown is merely one example of a luminaire according to the invention. Any suitable type of luminaire is conceivable, such as, but not limited to, luminaires shaped as light strips or square luminaires. In the former case, the light-emitting device 1 may include an array 2 of light-emitting elements, which may be configured or formed as a one-dimensional array of light-emitting elements 2. In the latter case, the light-emitting device 1 may include an array 2 of light-emitting elements, which may be configured or formed as a two-dimensional array 2 of light-emitting elements.

[0071] Hanging lamps, floor lamps, wall-mounted lamps, ceiling lamps, chandeliers, reading lamps, outdoor lamps, and clock lamps are also feasible.

[0072] Those skilled in the art will recognize that the present invention is by no means limited to the preferred embodiments described above. Rather, many modifications and variations are possible within the scope of the appended claims.

[0073] Furthermore, by studying the accompanying drawings, the disclosure, and the appended claims, those skilled in the art can understand and implement variations of the disclosed embodiments in practicing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. The fact that certain measures are recited in mutually different dependent claims does not imply that combinations of these measures cannot be advantageously used.

Claims

1. A light-emitting device (1), comprising: An array of light-emitting elements (2) is configured to emit light in the main emission direction (M) during operation, and Lens array (3) is arranged to cover at least a portion of the light-emitting element array, wherein Each lens of the lens array (3) is arranged to cover the light-emitting elements of the light-emitting element array, wherein Each lens in the lens array (3) is a freeform lens, and in which The lens array (3) includes a plurality of first lenses (31) and a plurality of second lenses (32), the plurality of first lenses (31) being configured to guide the light emitted by the light-emitting element in a first direction (D1) different from the main emission direction (M), and the plurality of second lenses (32) being configured to guide the light emitted by the light-emitting element in a second direction (D2) different from the main emission direction (M), wherein the first direction (D1) is different from the second direction (D2). The lenses of the plurality of first lenses (31) and the lenses of the plurality of second lenses (32) are alternately arranged in the lens array, and The plurality of first lenses (31) therein are freeform lenses configured to collimate the light emitted by the light-emitting element.

2. The light-emitting device according to claim 1, wherein the lenses of the plurality of first lenses (31) and the lenses of the plurality of second lenses (32) include mutually different surface profiles (33; 34).

3. The light-emitting device according to any one of the preceding claims, wherein the plurality of second lenses (32) are configured to include freeform lenses in the shape of peanuts.

4. The light-emitting device according to any one of the preceding claims, wherein the plurality of second lenses (32) are configured to guide the main portion of the light emitted by the light-emitting element at a beam angle (A2) between 40 degrees and 65 degrees relative to the main emission direction (M).

5. The light-emitting device according to any one of the preceding claims, wherein the plurality of first lenses (31) are configured to provide a first beam angle (A1) for light emitted by the light-emitting element, wherein the plurality of second lenses (32) are configured to provide a second beam angle (A2) for light emitted by the light-emitting element, and wherein the first beam angle (A1) is smaller than the second beam angle (A2).

6. The light-emitting device according to claim 5, wherein the first beam angle (A1) is at least 2 × 10 degrees, or at least 2 × 15 degrees, or at least 2 × 20 degrees smaller than the second beam angle (A2).

7. The light-emitting device according to claim 5 or 6, wherein the first beam angle (A1) is 2×45 degrees or 2×50 degrees or 2×55 degrees, and wherein the second beam angle (A2) is 2×60 degrees or 2×65 degrees or 2×70 degrees.

8. The light-emitting device according to any one of the preceding claims, wherein the light emitted by the light-emitting elements of the light-emitting element array (2) comprises a variable color spectrum.

9. The light-emitting device according to any one of the preceding claims, wherein the light emitted by the light-emitting element (21) covered by the plurality of first lenses (31) has a first color spectrum, wherein the light emitted by the light-emitting element (22) covered by the plurality of second lenses (32) has a second color spectrum, and wherein, according to the variation E ( The first chromatogram is different from the second chromatogram, as quantified by ) 10. The light-emitting device according to any one of the preceding claims further includes a controller (7) configured to individually control the spectrum of light emitted by the light-emitting elements of the light-emitting element array (2).

11. The light-emitting device according to any one of the preceding claims, wherein the light-emitting element array (2) and the lens array (3) are arranged on a substrate (4).

12. The light-emitting device according to any one of the preceding claims, wherein the light-emitting element array (2) forms an LED strip, The light-emitting element array (2) is a two-dimensional array of light-emitting elements.

13. The light-emitting device according to any one of the preceding claims, further comprising one or more of the following: A diffuser plate (6) is arranged above the array of light-emitting elements, and The housing (5) contains the light-emitting element array and the lens array.

14. A luminaire comprising at least one light-emitting device (1) according to any one of the preceding claims.

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