The present invention relates to lighting, and more specifically, to optical systems for solid state light sources.
Due to its size and structure, light emitted from a solid state light source often looks like it comes from a single point. A group of solid state light sources thus creates the effect of many points of light that might blend together, but are otherwise at least partially seen as distinct. This results in dim spots, dark spots, bright spots, and the like. Due to the typical uniformity of light created by conventional light sources, and the aesthetically pleasing qualities of that uniformity, it is desirable to have uniformity in light emitted by solid state light sources, too. Typically, this results when a batwing distribution is created, using known optical devices such as lenses and films.
Conventional techniques for creating a batwing distribution add cost and create their own issues, such as increased glare and/or sensitivity to the position of the solid state light source. In some applications and/or devices, adding a lens or a film is not practical, and thus specialized solid state light sources which include optics themselves must be used, potentially significantly increasing cost. Embodiments are designed to create a uniform distribution of light from solid state light sources, in two dimensions, while also reducing glare and cost.
Embodiments provide flexible optical systems, as well as combinations of such systems with various films including patterned microstructures, referred to through as hybrid optical systems. The design of these flexible optical systems and hybrid optical systems redirects incident light emitted from one or more solid state light sources located within cellular optical elements of each, cut off at particular angles by the cellular optical elements, so as to create a certain light distribution. In embodiments of the hybrid optical systems, one or more films are added to the cellular optical elements to further change the light distribution. In some embodiments, the hybrid optical systems use one or more lenses instead of one or more films. In some embodiments, a plurality of films are placed within the optical cellular elements. Films including patterned microstructures, in some embodiments, are on a flat film material, and in some embodiments, are on a flexible film material. Some embodiments include such microstructures on both sides of the film, in order to reduce and/or better control glare. The resultant light distribution is uniform and/or substantially uniform across a wide field.
In an embodiment, there is provided a hybrid optical system. The hybrid optical system includes: a cellular optical element, comprising a first opening, a second opening, and a space defined therebetween; and a light control film, comprising a single layer of light transparent material comprising a first side and a second side, and a plurality of first microstructures formed on the first side; wherein the light control film is located within the space of the cellular optical element.
In a related embodiment, the cellular optical element may include a pyramid shape. In another related embodiment, the cellular optical element may include a volcano-like shape. In still another related embodiment, the cellular optical element may include a frustum shape.
In yet another related embodiment, the cellular optical element may include a stepped pyramid shape. In a further related embodiment, the stepped pyramid shaped cellular optical element may include a base including the first opening and a plurality of steps from the base to the second opening. In a further related embodiment, the light control film may be placed across a step in the plurality of steps of the stepped pyramid shaped cellular optical element. In a further related embodiment, a second light control film may be placed across a second step in the plurality of steps of the stepped pyramid shaped cellular optical element. In another further related embodiment, the light control film may be coupled to the step. In yet another further related embodiment, the cellular optical element further may include an insert placed on the light control film, the insert may have a stepped pyramid shape, corresponding to the stepped pyramid shape of the cellular optical element and including a set of steps that extends from the light control film to the second opening. In a further related embodiment, the insert may be coupled to the cellular optical element so as to hold the light control film on the step within the cellular optical element.
In still another further related embodiment, the cellular optical element may include a lower section including the base and configured to receive an insert, and an insert including the second opening. In a further related embodiment, the lower section may include a first set of steps, and the insert may include a second set of steps. In a further related embodiment, the light control film may be placed in the lower section across a first step in the first set of the plurality of steps that is immediately above the base, such that the first set of steps of the lower section is equal to the second set of steps of the insert. In a further related embodiment, the light control film may be placed in the lower section at a number of steps above the first step, and the second set of steps of the insert is equal to the first set of steps less the number of steps.
In yet another further related embodiment, the stepped pyramid shape may include a single step. In a further related embodiment, the light control film may be placed across the single step of the stepped pyramid shape.
In still yet another related embodiment, the cellular optical element may include a receiving portion and a corresponding insert, the light control film may be placed within the receiving portion and may be held in place by the corresponding insert. In a further related embodiment, the cellular optical element may include a lower section including a base including the first opening, the lower section may be configured to receive an insert, and an insert including the second opening. In a further related embodiment, the lower section and the insert together may include a plurality of steps, wherein at least one step of the lower section may overlap with at least one step of the insert. In another further related embodiment, the insert may be correspondingly shaped to the lower section.
In yet still another related embodiment, wherein the first opening may be configured to receive a light source and the second opening may be configured to emit light exiting the hybrid optical system. In a further related embodiment, the cellular optical element may extend in an outward direction from the first opening to the second opening.
In still yet another related embodiment, the second opening may be configured to receive a light source and the first opening may be configured to emit light exiting the hybrid optical system. In yet still another related embodiment, the cellular optical element may include a plurality of cellular optical elements, each including a first opening, a second opening, and a space defined therebetween. In a further related embodiment, the plurality of cellular optical elements may be interconnected so as to occupy a plane.
In yet another related embodiment, a vertical cross-section of the cellular optical element may include a portion of the first opening, a portion of the second opening, and two walls, each wall may have an acute angle relative to the first opening. In a further related embodiment, the acute angle of each wall may be chosen so as to achieve a particular light distribution from a light source located at the first opening of the cellular optical element, independent of any optical effects of the light control film.
In still another related embodiment, the cellular optical element may have a lower portion and an upper portion, the lower portion may include the first opening and the upper portion may include the second opening. In a further related embodiment, the first opening may be configured to receive a light source. In a further related embodiment, light emitted by a light source located at the first opening in the lower portion of the cellular optical element may exit the hybrid optical system by first passing through the light control film and then passing through the second opening in the upper portion of the cellular optical element. In another further related embodiment, the second opening may be configured to receive a light source. In a further related embodiment, light emitted by a light source located at the second opening in the upper portion of the cellular optical element may exit the hybrid optical system by first passing through the light control film and then passing through the first opening in the lower portion of the cellular optical element.
In another further related embodiment, each cellular optical element in the plurality of cellular optical elements may have a lower portion and an upper portion, the lower portions may be joined together to interconnect the plurality of cellular optical elements. In a further related embodiment, the lower portions may be joined together by a material, the material may be a same material used to construct the plurality of cellular optical elements, and the material may have a substantially planar shape where interconnecting the plurality of cellular optical elements.
In yet still another related embodiment, the hybrid optical system may further include a lens located within the space of the cellular optical element. In still another related embodiment, the light control film may be angled within the space of the cellular optical element.
In another further related embodiment, the light control film may be angled within the space so as to rest on at least two different steps of the stepped pyramid shape. In yet another further related embodiment, the plurality of interconnected cellular optical elements may include a flexible optical system, the flexible optical system may be capable of entering a set of states, the set of states may include a substantially flat state and a substantially flexed state.
In still yet another related embodiment, the light control film may include a lens. In yet another related embodiment, the cellular optical element may reflect light from a light source located at least partially within the cellular optical element. In a further related embodiment, the cellular optical element may reflect light from a light source located at least partially within the cellular optical element prior to the light passing through the light control film and after the light passes through the light control film.
In yet another related embodiment, the light control film may be configured to receive incident light on the first side and to produce an off-axis light distribution in a light field downstream of the second side, and the light control film may further include a plurality of second microstructures on the second side, the second microstructures configured to reduce glare in the off axis light distribution.
In another embodiment, there is provided a hybrid optical system. The hybrid optical system includes: a plurality of interconnected cellular optical elements, each comprising a first opening, a second opening, and a space defined therebetween; and a plurality of lenses, wherein each lens in the plurality of lens is located within the space of a corresponding cellular optical element in the plurality of interconnected cellular optical elements.
In another embodiment, there is provided a hybrid optical system. The hybrid optical system includes: a plurality of interconnected cellular optical elements, each including a first opening, a second opening, and a space defined therebetween; and a plurality of lenses, wherein each lens in the plurality of lens is located within the space of a corresponding cellular optical element in the plurality of interconnected cellular optical elements.
In yet another embodiment, there is provided a lighting device. The lighting device includes one or more solid state light sources; a hybrid optical system, including: a plurality of interconnected cellular optical elements, each cellular optical element comprising a first opening, a second opening, and a space defined therebetween, wherein a corresponding one of the solid state light sources is located within either the first opening or the second opening of each cellular optical element; and one or more light control films, each including a single layer of light transparent material comprising a first side and a second side, and a plurality of first microstructures formed on the first side; wherein the one or more light control films are located within the space of the plurality of interconnected cellular optical elements; wherein the one or more solid state light sources are coupled to the hybrid optical system so as to form the lighting device.
In a related embodiment, the lighting device may include a luminaire. In another related embodiment, the lighting device may be located within a space. In a further related embodiment, the space may be defined by a ceiling tile. In still another related embodiment,
The foregoing and other objects, features and advantages disclosed herein will be apparent from the following description of particular embodiments disclosed herein, as illustrated in the accompanying drawings in which like reference characters refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles disclosed herein.
Embodiments provide thermal formed sheets of polymer, such as but not limited to PET, which are able to achieve desired cut-off angles by being shaped into one or more cellular optical elements. When one or more cellular optical elements are combined with one or more microstructures-based light control films, such as but not limited to a plurality of pyramid-shaped microstructures, a hybrid optical system is created.
The one or more light control films 104 are made of, for example but not limited to, a single layer of light transparent material including a first side 104A and a second side 104B, and a plurality of microstructures 104C formed on the first side 104A (and not easily visible in the figures due to their small size). The light control film 104 is located within the space 108 of the cellular optical element 102, as shown in
In some embodiments, the plurality of microstructures 104C are any known shapes, including combinations thereof. Thus, in some embodiments, the light control film 104 includes one or more pyramid-shaped microstructures, which include but are not limited to different shapes of pyramid (e.g. a four sided pyramid, five sided pyramid, six sided pyramid, seven sided pyramid, eight sided pyramid, and so on). In some embodiments, the plurality of microstructures 104C are different shapes altogether (for example but not limited to cone shape), any and all of different sizes. When the microstructures 104C face toward the light sources 110, a particular light distribution, such as but not limited to a batwing distribution, results. When the microstructures 104C face away from the light sources 110, the light distribution changes (e.g., the light focuses). In some embodiments, the light control film includes a plurality of second microstructures 104D (and not visible in the figures due to their small size) on the second side 104B of the light control film 104. In some embodiments, the light control film 104 is configured to receive incident light on the first side 104A and to produce an off-axis light distribution in a light field downstream of the second side 104B. In some embodiments, the second microstructures 104D are configured to create a different distribution or effect than the first microstructures 104C, such as but not limited to reducing glare, reducing glare in an off axis light distribution, and so on. Depending on the application, any type of light control film may be used, such as but not limited to a diffuser film, which may or may not include microstructures. Such light control films are described in greater detail in co-pending application entitled “LIGHT CONTROL FILMS AND LIGHTING DEVICES INCLUDING SAME” and filed on the same day as the current application.
As seen in
As shown throughout the figures, the cellular optical elements of hybrid optical systems according to embodiments may take many shapes, including but not limited to conical shapes, volcano-like shapes, pyramid shapes, flat top pyramid shapes, apex pyramid shapes, stepped pyramid shapes, frustum shapes, multiple-sided (i.e., three side, four sided, five sided, six sided, seven sided, eight sided and so forth) pyramid shapes, hemispherical shapes, dome shapes, spheroid shapes, and so on. Singular examples of some of these shapes 400, 409, 410 are shown in
As shown more easily in
As shown in
Of course, in some embodiments, all of the cellular optical elements 102A are the same within a given hybrid optical system 100A, as shown in
Referring to
In some embodiments, such as shown in
Some embodiments of the hybrid optical system use a different optical element than a light control film. For example, embodiments shown in
In some embodiments, the light source 110 is not necessarily at normal incidence. For example, a stronger batwing distribution at a higher angle can be achieved, or an asymmetrical beam distribution can be obtained, if the optical element (i.e., the light control film and/or the lens) is tilted at an angle, as shown in
Further, in some embodiments, such as shown in
Table 1 shows a summary of results. For bare Lambertion distributed solid state light sources, such as but not limited to LEDs, the spacing criteria is only 1.3. The spacing criteria is increased to 1.84 with just a light control film film. However, the glare is worse as more light will be in the zones of sixty to eighty degrees and eighty to ninety degrees. The efficiency of the light control film is eighty-seven percent. If a pyramid-shaped flexible optical system is placed around the LEDs, the spacing criteria is dropped to 1.26 and the efficiency is dropped by five percent compared to the LED only case. A hybrid optical system will bring the spacing criteria to 1.54 while maintaining the cut-off angle of fifty degrees. The efficiency is six percent less compared to the light control film only case. Because the light control film will redistribute more light to higher angles, the efficiency drops six percent for the hybrid optical system vs. the light control film only, compared to five percent for the flexible optical system only vs. the LED only. Tradeoffs exist between spacing criteria, glare, and efficiency. Specifically, a design with larger spacing criteria and less glare will result in a lower optical efficiency.
As described above, in some embodiments, to achieve a higher optical efficiency, it is desired that the substrate on which the light sources are placed itself has a high reflectivity. This is achieved, in some embodiments, through the use of, for example but not limited to, white polymer film, such as but not limited to white PET film, which may be and in some embodiments is flexible, though this is not required.
Further, in some embodiments, the light control film is not placed within the cellular optical element(s), but rather is placed on top of the cellular optical elements, such that it is not located in a spaced defined by the cellular optical element but rather is outside of the opening through which light passes when exiting the cellular optical element.
In some embodiments, the one or more light control films 104K/104L of
Unless otherwise stated, use of the word “substantially” may be construed to include a precise relationship, condition, arrangement, orientation, and/or other characteristic, and deviations thereof as understood by one of ordinary skill in the art, to the extent that such deviations do not materially affect the disclosed methods and systems.
Throughout the entirety of the present disclosure, use of the articles “a” and/or “an” and/or “the” to modify a noun may be understood to be used for convenience and to include one, or more than one, of the modified noun, unless otherwise specifically stated. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
Elements, components, modules, and/or parts thereof that are described and/or otherwise portrayed through the figures to communicate with, be associated with, and/or be based on, something else, may be understood to so communicate, be associated with, and or be based on in a direct and/or indirect manner, unless otherwise stipulated herein.
Although the methods and systems have been described relative to a specific embodiment thereof, they are not so limited. Obviously many modifications and variations may become apparent in light of the above teachings. Many additional changes in the details, materials, and arrangement of parts, herein described and illustrated, may be made by those skilled in the art.
The present application is an international application of, and claims priority to, U.S. Provisional Application No. 62/005,963, entitled “HYBRID OPTICS” and filed May 30, 2014, U.S. Provisional Application No. 62/005,946, entitled “OPTICAL FILM WITH MICROSTRUCTURES ON OPPOSING SIDES” and filed May 30, 2014, U.S. Provisional Application No. 62/142,779, entitled “OPTICAL FILM AND CHIP PACKAGE WITH ENGINEERED MICROSTRUCTURES” and filed Apr. 3, 2015, and U.S. Provisional Application No. 62/005,972, entitled “INTEGRATED OPTICS AND INTEGRATED LIGHT ENGINES” and filed May 30, 2014, the entire contents of all of which are hereby incorporated by reference.
Filing Document | Filing Date | Country | Kind |
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PCT/US2015/033605 | 6/1/2015 | WO | 00 |
Number | Date | Country | |
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62005963 | May 2014 | US | |
62005946 | May 2014 | US | |
62142779 | Apr 2015 | US |