US20170114983A1

US20170114983A1 - Hybrid optical systems including flexible optical systems and light control films

Info

Publication number: US20170114983A1
Application number: US15/315,074
Authority: US
Inventors: Zhuo Wang; Bruce Radl; Douglas Harriott
Original assignee: Osram Sylvania Inc
Current assignee: Acuity Brands Lighting Inc
Priority date: 2014-05-30
Filing date: 2015-06-01
Publication date: 2017-04-27
Also published as: US20170097448A1; US10260711B2; WO2015184456A1; EP3149395A1

Abstract

A hybrid optical system, and lighting devices including the same, are provided. The hybrid optical system includes a cellular optical element a light control film. The cellular optical element includes a first opening, a second opening, and a space defined therebetween. The light control film includes a single layer of light transparent material having a first side and a second side, and a plurality of first microstructures formed on the first side. The light control film is located within the space of the cellular optical element. The light control film may include a plurality of second microstructures formed on the second side to reduce glare. The hybrid optical system may include a plurality of interconnected cellular optical elements.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

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.

TECHNICAL FIELD

The present invention relates to lighting, and more specifically, to optical systems for solid state light sources.

BACKGROUND

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.

SUMMARY

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,

BRIEF DESCRIPTION OF THE DRAWINGS

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.

FIG. 1 shows a hybrid optical system, including a cut away of a portion of the hybrid optical system, including cellular optical elements and light control films, according to embodiments disclosed herein.

FIG. 2 shows a light distribution for a hybrid optical system, according to embodiments disclosed herein.

FIGS. 3A-3B show a hybrid optical system having conical volcano-like shapes, according to embodiments disclosed herein.

FIG. 3C shows a close-up of a portion of the hybrid optical system of FIGS. 3A-3B.

FIGS. 4A-4C show respective examples of individual cellular optical elements for use in hybrid optical systems, according to embodiments disclosed herein.

FIG. 5 shows a hybrid optical system having stepped pyramid shapes, according to embodiments disclosed herein.

FIG. 6 shows a hybrid optical system having linear pyramid shapes, according to embodiments disclosed herein.

FIGS. 7A-7D show hybrid optical systems with various linear shapes, according to embodiments disclosed herein.

FIGS. 8A-8B show hybrid optical systems including inserts, according to embodiments disclosed herein.

FIGS. 9A-9D show vertical cross sections of the hybrid optical system of FIG. 5 according to embodiments disclosed herein.

FIGS. 10A-10C show vertical cross sections of hybrid optical systems including a lens, according to embodiments disclosed herein.

FIG. 11 shows a vertical cross section of a hybrid optical system including two or more optical elements, according to embodiments disclosed herein.

FIG. 12 shows various distributions for an LED, a LED with a light control film, an LED with a flexible optical system, and an LED with a hybrid optical system, according to embodiments disclosed herein.

FIGS. 13A-13B show a luminaire and a ceiling tile, respectively, including a hybrid optical system, according to embodiments disclosed herein.

DETAILED DESCRIPTION

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.
FIG. 1 shows a hybrid optical system 100 that combines, as shown more clearly in the cut out, one or more cellular optical elements 102 with one or more light control films 104. The one or more cellular optical elements 102, which in some embodiments are a flexible optical system, include a first opening 105, a second opening 106, and a space 108 defined therebetween. In some embodiments, as shown in FIG. 1, the one or more cellular optical elements 102 are a plurality of shapes made from thermally formed polymer, such as but not limited to PET, which sit on top of a substrate (not shown in FIG. 1 due to being obscured by the one or more cellular optical elements 102) including a plurality of solid state light sources 110. In some embodiments, such as shown in FIG. 1, the cellular optical elements 102 have a pyramid shape, though of course other shapes are possible and are used in some embodiments, as described in greater detail below (for example, see FIGS. 3A-3C). In some embodiments, each cellular optical element 102 in the plurality of cellular optical elements 102 has a single solid state light source 110 within. In some embodiments, each cellular optical element 102 in the plurality of cellular optical elements 102 has more than one solid state light source within that reflector. In some embodiments, the number of solid state light sources within a single cellular optical element 102 varies. In some embodiments, there is at least one cellular optical element that does not include a solid state light source (see, for example, FIG. 7A). In some embodiments, as shown in FIG. 1, the second opening 106 is configured to receive the light source 110 and the first opening 105 is configured to emit light exiting the hybrid optical system 100. As described in greater detail below, in some embodiments, the cellular optical elements 102 are interconnected so as to occupy a plane 150.
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 FIG. 1. More specifically, in some embodiments, a larger light control film is cut into small pieces, and at least one piece is placed over the one or more solid state light sources 110 within each cellular optical element 102. In some embodiments, each individual solid state light source 110 receives its own distinct piece of light control film 104; in some embodiments, where there are more than one solid state light source 110 within a cellular optical element 102, the solid state light sources 110 may share a piece of light control film 104. The film may be mounted in any known way, as described in greater detail herein.
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.
FIG. 2 shows a vertical cross-section of an embodiment of the hybrid optical system 100 of FIG. 1 overlaid on a light distribution 200 thereof. In FIG. 2, the light control film 104 is placed above the light source 110 within a thermal formed polymer-based cellular optical element 102. The cellular optical element 102 reflects light emitted by the light source 110 at a higher angle above, for example, fifty degrees, and in combination with the light control film 104, also reduces the glare from the light source 110. In some embodiments, the cellular optical element 102 is Lambertion (e.g., white), and in some embodiments, the cellular optical element 102 is specular, and in some embodiments the cellular optical element 102 is a combination of both. As a result, the hybrid optical system 100 shows a mild batwing distribution 200 with a cut-off angle at fifty degrees, as seen in FIG. 2.
As seen in FIG. 2, the cross-section of the cellular optical element 102 includes a portion of a first opening 105A and a portion of a second opening 106A. The cellular optical element 102 also includes two walls 102A, 102B. Each wall 102A, 102B has an acute angle relative to the portion of the first opening 105A. This angle, in some embodiments, is measured with respect to the second opening 106A. The acute angle of each wall 102A, 102B is chosen so as to achieve a particular light distribution from the light source 110 located within the cellular optical element 102, independent of any optical effects of the light control film 104 also located within the cellular optical element 102. In the cross section shown in FIG. 2, the second opening 106A is configured to receive the light source 110, and thus when the light source 110 emits light, this light exits the hybrid optical system 100 by first passing through the light control film 104 and then passing through the first opening 105A. In some embodiments, as also shown in FIG. 2, the cellular optical element 102 reflects light from the light source 110, located at least partially within the cellular optical element 102, prior to the light passing through the light control film 104, and after the light passes through the light control film 104.
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 FIGS. 4A, 4B, and 4C, respectively.
FIGS. 3A-3C show embodiments of a hybrid optical system where the cellular optical elements are volcano-like shapes. FIG. 3A shows a hybrid optical system 100A including a plurality of interconnected cellular optical elements 102A, each including a light control film 104A (not visible in FIG. 3A but shown in FIG. 3B). As stated above, the cellular optical elements 102A are in the shape of volcanos, with an open top and a conical interior that decreases from the top to the bottom of the volcano, where a light source 110A (not visible in FIG. 3A but shown in FIG. 3B) is located. Thus, each cellular optical element 102A includes a first opening 305A and a second opening 306A. The first opening 305A is configured to receive the light source 110A and the second opening 306A is configured to emit light exiting the hybrid optical system 100A. As shown in FIG. 3A, the cellular optical elements 102A extend in an outward direction from the first opening 305A to the second opening 306A.
As shown more easily in FIG. 3C, a cellular optical element 300A has a lower portion 310 and an upper portion 320. The lower portion 310 includes the first opening 305A and the upper portion 320 includes the second opening 306A. Light emitted by the light source 110 located at the first opening 305A in the lower portion 310 of the cellular optical element 102A exits the hybrid optical system 100A by first passing through the light control film 104, which sits immediately over the light source 110, and then passing through the second opening 306A in the upper portion 320 of the cellular optical element 102A.
As shown in FIGS. 3A-3C, the cellular optical elements 102A are joined together so as to form a sheet of cellular optical elements 102A, which in some embodiments is a flexible optical system. In some embodiments, it is the lower portions 310 of the cellular optical elements 102A that are joined together, and thus interconnect the cellular optical elements 102A. In some embodiments, as shown in FIG. 1, it is the upper portions of the cellular optical elements 102 that are joined together so as to interconnect the cellular optical elements 102. Returning to FIGS. 3A-3C, the lower portions 310 are joined together by a material 311, wherein the material 311 is the same material used to construct the cellular optical elements 102A. As shown most clearly in FIGS. 3B and 3C, the material 311 has a substantially planar shape where interconnecting the cellular optical elements 102A. In embodiments where the material 311 is flexible, the cellular optical elements 102A are a flexible optical system 103A, which is capable of entering a set of states, including but not limited to a substantially flat state, as shown in FIGS. 3B and 3C, and a substantially flexed state, as shown in FIG. 3A.
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 FIGS. 3A-3C, and in some embodiments, the shapes of the cellular optical elements vary within the same hybrid optical system.
FIG. 6 shows a hybrid optical system 100C, where each cellular optical element 102C includes more than one light source 110C, but a single light control film 104C. As shown in FIG. 6, the cellular optical elements 102C are in the shape of linear pyramids, or linear trays, or open troughs, interconnected. FIGS. 7A-7D show various embodiments of hybrid optical systems 100D, 100E, 100F, and 100G that are also linear in shape. In FIG. 7A, the hybrid optical system 100D includes a plurality of cellular optical elements 102D that are partial cubes with an open top and an opening in a bottom (top and bottom being used to denote relational direction and not requiring that the ‘top’ face upward or that the ‘bottom’ face downward) to receive light sources 110D. In some embodiments, the partial cubes 102D are formed by placing walls across a linear cellular optical element. FIGS. 7C and 7D show the hybrid optical systems 100F and 100G, respectively, which are similar in shape to a single cellular optical element 102C of FIG. 6, but which are divided into smaller cellular optical elements 102F and 102G, respectively, but a plurality of walls 700. IN FIG. 7C, the cellular optical elements 102F of the hybrid optical system 100F each include two light sources 110F, while in FIG. 7D, the cellular optical elements 102G of the hybrid optical system 100G each include three light sources 110G. Of course, the cellular optical elements may include any number of light sources. FIG. 7B shows the hybrid optical system 100E, which is similar in overall shape to the hybrid optical systems 100F and 100G of FIGS. 7C and 7D, but is instead divided into small cellular optical elements 102E by a plurality of angled dividers 700E. Such cellular optical elements as shown in FIGS. 6-7D may be, and in some embodiments are, used with linear light engines (not shown in FIGS. 6-7D).
FIGS. 8A and 8B shows embodiments of a hybrid optical system where one or more inserts are used to hold the light control film(s) in place within the cellular optical elements. In FIG. 8A, one or more cellular optical elements 102H include a receiving portion 102H-1 and a corresponding insert 102H-2, a portion of which is not yet inserted. The light control film 104 is placed within the receiving portion 102H-1 and is held in place by the corresponding insert 102H-2. The fully inserted insert 102H-2 is shown in FIG. 8B. In some embodiments, the receiving portion 102H-1 includes a base including a first opening 105H and the insert 102H-2 includes a second opening 106H. In some embodiments, as shown in FIG. 8A, the receiving portion 102H-1 and the insert 102H-2 together include a plurality of steps 800, wherein at least one step 801 of the receiving portion 102H-1 overlaps with at least one step 802 of the insert 102H-2. In some embodiments, the insert 102H-2 is correspondingly shaped to the receiving portion 102H-1, such that the combined cellular optical element 102H looks the same as such a cellular optical element that is not formed from a receiving portion 102H-1 and an insert 102H-2 (see, for example, a cellular optical element 102B shown in FIG. 5).
Referring to FIG. 5, a plurality of cellular optical elements 102B in the shape of stepped pyramids are shown. These cellular optical elements 102B, when combined with one or more light control films 104B, as shown in FIGS. 9A-9E, form a hybrid optical system 100B. Each cellular optical element 102B, which are shown in vertical cross-section in FIG. 9A, includes a base 910, which has a first opening 105B, and a plurality of steps 920 from the base 910 to a second opening 106B. The light control film 104B is placed across a step 920-1 in the plurality of steps 920. In some embodiments, an optional second light control film 104B-2 is placed across a second step 920-2 in the plurality of steps 920. In some embodiments, the light control film 104B is coupled to the step 920-1 using any known coupling agent or mechanism, such as but not limited to glue, adhesive, static electricity, or use of an optional insert 900 that is similarly shaped to the cellular optical element 102B. That is, the optional insert 900 has a stepped pyramid shape, corresponding to the stepped pyramid shape of the cellular optical element 102B and includes a set of steps 930 that extends from the light control film 104B to the second opening 106B. In some embodiments, the optional insert 900 is coupled to the cellular optical element 102B so as to hold the light control film 104 on the step 920-1 within the cellular optical element 102B.
In some embodiments, such as shown in FIG. 9A, where the light control film 104B is placed across the step 920-1, which is the step immediately above the base 910, and the optional insert 900 is placed within the cellular optical element 102B, the cellular optical element 102B has the same number of steps as the optional insert 900. In some embodiments, where the light control film 104B is placed on a higher step, as shown in FIG. 9B (such as the second step 920-2 from the base 910), an optional insert 900B includes a set of steps 930B that is equal to the plurality of steps 920 of the cellular optical element 102B less the number of steps the light control film 104B is placed above the first step 920-1 above the base 910. Thus, in the given example shown in FIG. 9B, the cellular optical element 102B includes two steps, and the optional insert 900B includes one step. In some embodiments, as shown in FIG. 9E, the stepped pyramid shape of the cellular optical element 102B includes only a single step 920B, and the light control film 104B is placed across this single step 920B. In some embodiments, as shown in FIG. 9C, the light control film 104B is angled within the cellular optical element 102B. In some embodiments, as shown in FIG. 9C, this results in the light control film 104B resting on at least two different steps 920-1, 920-2 of the cellular optical element 102B having the stepped pyramid shape. Such embodiments permit the creation of different cut-off angles and spacing criteria with the same design depending on where the light control film is placed, how many steps are present, the angles of the steps (which need not be consistent from one step to the next up or down the pyramid), and so forth.
Some embodiments of the hybrid optical system use a different optical element than a light control film. For example, embodiments shown in FIGS. 10A-10C use a lens instead of the light control film. Thus, FIG. 10A shows a hybrid optical system 100I including a lens 1041 and a cellular optical element 1021. The lens 1041 is located within a space 1081 of the cellular optical element 1021. The lens 1041 may be, and in some embodiments is, any known type of lens, such as but not limited to a Fresnel lens that achieves a spotlight distribution with cut-off options. In some embodiments, the lens 1041 is placed in a location similar to, and in some embodiments the same/substantially the same as, the light control film. It is noted that while some light control films are insensitive to the relative position of the light source 110, some lenses, such as a Fresnel lens, are location sensitive. The use of such a location sensitive optic will bring some advantages to the design at the expense of flexibility, etc. Thus, some embodiments off-set the lens with respect to the light sources, and the result is that light emitted to/from the light source 110 may be aimed to different angles, achieving a greater flexibility in the design. Instead of moving the lens 1041 or using a different lens, in some embodiments, as shown in FIG. 10B, the light source 110 itself is movable within the hybrid optical system 100I, for example but not limited to through use of a moving mechanism, such as having an opening 1051 in the cellular optical element 1021 that is larger than the light source 110. This results in the aesthetics of the hybrid optical system 100I being maintained using the same materials and cut-off angles, as is shown in FIG. 10B.
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 FIG. 10C. In some embodiments, such as those described above with regards to FIG. 10C, the relative position of the light source to the lens and/or to the film needs to be controlled.
Further, in some embodiments, such as shown in FIG. 11, a multi-optical element hybrid optical system 100J is possible, combining one or more light control films 104J-1, one or more lenses 104J-2, and/or combinations thereof, all located within a cellular optical element 102J. A simultaneous specific beam shaping function results, and again, in some embodiments, the relative position of the light source(s) 110 to the optical elements 104J may needs to be controlled, as well as the relative position of the optical elements 104J with respect to each other.
FIG. 12 shows candela distributions of a solid state light source only 1201, a light control film only 1202, a flexible optical system only 1203, and a hybrid optical system combining the light control film with the flexible optical system 1204. As shown in FIG. 12, the light control film only distribution 1202 provides a large batwing distribution but the glare is worse compared to the solid state light source only distribution 1201. A cut-off angle of fifty degrees can be realized for both the flexible optical system only distribution 1203 and the hybrid optical system distribution 1204, particularly when the flexible optical system comprises a sheet of a plurality of pyramid shapes, as described above.
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.

TABLE 1

Comparisons

	Light	Flexible	Hybrid
LED	Control	Optical	Optical
only	Film only	System Only	System

Spacing criterion (0-180)	1.30	1.84	1.26	1.54
Spacing criterion (0-180)	1.34	1.94	1.28	1.54
Spacing criterion	1.42	2.08	1.36	1.70
(Diagonal)
Light in zone 60-80	20.8%	23.7%	7.5%	8.4%
Light in zone 80-90	2.9%	3.5%	1.8%	2.1%
Flux (lm)	856	744	812	693
Efficiency	100%	87%	95%	81%

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.
FIG. 13A shows a lighting device 1000 including a hybrid optical system 100K, according to embodiments disclosed herein. The lighting device 1000 includes one or more solid state light source 110K and the hybrid optical system 100K. The hybrid optical system 100K includes a plurality of interconnected cellular optical elements 102K, each including a first opening 105K, a second opening 106K, and a space 108K defined therebetween. A corresponding one of the solid state light sources 110K is located within either the first opening 105K or the second opening 106K of each cellular optical element 102K. The hybrid optical system 100K also includes one or more light control films 104K. The one or more light control films 104K each include a single layer of light transparent material, meaning that light is capable of traveling through the material. The light transparent material includes a first side 104K-1 and a second side 104K-2, with a plurality of first microstructures 104K-3 formed on the first side 104K-1. The one or more light control films 104K are located within the space 108K of the plurality of interconnected cellular optical elements 102K. The one or more solid state light sources 110K are coupled to the hybrid optical system 100K so as to form the lighting device 1000. As is seen in FIG. 13A, the lighting device 1000 does not include, or indeed in some embodiments, require a housing or any portion of a housing, though in some embodiments, the lighting device 1000 includes a housing (not shown), which in some embodiments includes locations for one or more power supplies, one or more control elements, wiring, and so on. In some embodiments, as shown in FIG. 13A, the lighting device 1000 comprises a luminaire.
FIG. 13B shows a lighting device 1000A including a hybrid optical system 102L and one or more solid state light sources 110L similar in structure though not size to the lighting device 1000 of FIG. 13A. In FIG. 13B, the lighting device 1000A is sized so as to fit within a space, and indeed is located with a space created by making a hole in a ceiling tile 1001. Thus, the ceiling tile 1001 shown in FIG. 13B holds the lighting device 1000A, such that the lighting device 1000A functions to illuminate an area in which the ceiling tile is installed.
In some embodiments, the one or more light control films 104K/104L of FIGS. 13A-13B are configured to receive incident light on the first side 104K/104L-1 and to produce an off-axis light distribution in a light field downstream of the second side 104K-2/104L-2, and include a plurality of second microstructures 104K-4/104L-4 on the second side 104K-2/104L-2, the second microstructures 104K-4/104L-4 configured to reduce glare in the off axis light distribution.
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.

Claims

1. A hybrid optical system, comprising:

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.

2. The hybrid optical system of claim 1, wherein the cellular optical element comprises one of a pyramid shape, a volcano-like shape, a frustum shape, and a stepped pyramid shape.

3. (canceled)

4. (canceled)

5. (canceled)

6. The hybrid optical system of claim 2, wherein the cellular optical element comprises the stepped pyramid shape, and wherein the stepped pyramid shaped cellular optical element comprises a base including the first opening and a plurality of steps from the base to the second opening.

7. The hybrid optical system of claim 6, wherein the light control film is placed across a step in the plurality of steps of the stepped pyramid shaped cellular optical element.

8. The hybrid optical system of claim 7, wherein a second light control film is placed across a second step in the plurality of steps of the stepped pyramid shaped cellular optical element.

9. (canceled)

10. The hybrid optical system of claim 7, wherein the cellular optical element further comprises an insert placed on the light control film, wherein the insert has a stepped pyramid shape, corresponding to the stepped pyramid shape of the cellular optical element and comprising a set of steps that extends from the light control film to the second opening.

11. The hybrid optical system of claim 10, wherein the insert is coupled to the cellular optical element so as to hold the light control film on the step within the cellular optical element.

12. The hybrid optical system of claim 6, wherein the cellular optical element comprises a lower section including the base and configured to receive an insert, and an insert including the second opening.

13. The hybrid optical system of claim 12, wherein the lower section includes a first set of steps, and wherein the insert includes a second set of steps.

14. The hybrid optical system of claim 13, wherein the light control film is 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.

15. The hybrid optical system of claim 14, wherein the light control film is 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.

16. The hybrid optical system of claim 2, wherein the cellular optical element comprises the stepped pyramid shape, wherein the stepped pyramid shape includes a single step, and wherein the light control film is placed across the single step of the stepped pyramid shape.

17. (canceled)

18. The hybrid optical system of claim 1, wherein the cellular optical element comprises a receiving portion and a corresponding insert, wherein the light control film is placed within the receiving portion and is held in place by the corresponding insert.

19. The hybrid optical system of claim 2, wherein the cellular optical element comprises the stepped pyramid shape, wherein the cellular optical element comprises a lower section comprising a base including the first opening, wherein the lower section is configured to receive an insert, and an insert including the second opening.

20. The hybrid optical system of claim 19, wherein the lower section and the insert together comprise a plurality of steps, wherein at least one step of the lower section overlaps with at least one step of the insert.

21. The hybrid optical system of claim 19, wherein the insert is correspondingly shaped to the lower section.

22. The hybrid optical system of claim 1, wherein the first opening is configured to receive a light source and the second opening is configured to emit light exiting the hybrid optical system.

23. The hybrid optical system of claim 22, wherein cellular optical element extends in an outward direction from the first opening to the second opening.

24. The hybrid optical system of claim 1, wherein the second opening is configured to receive a light source and the first opening is configured to emit light exiting the hybrid optical system.

25. The hybrid optical system of claim 1, wherein the cellular optical element comprises a plurality of cellular optical elements, each comprising a first opening, a second opening, and a space defined therebetween.

26. The hybrid optical system of claim 25, wherein the plurality of cellular optical elements are interconnected so as to occupy a plane.

27. The hybrid optical system of claim 1, wherein a vertical cross-section of the cellular optical element includes a portion of the first opening, a portion of the second opening, and two walls, wherein each wall has an acute angle relative to the first opening.

28. The hybrid optical system of claim 27, wherein the acute angle of each wall is 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.

29. The hybrid optical system of claim 1, wherein the cellular optical element has a lower portion and an upper portion, wherein the lower portion includes the first opening and the upper portion includes the second opening.

30. The hybrid optical system of claim 29, wherein the first opening is configured to receive a light source, and wherein light emitted by a light source located at the first opening in the lower portion of the cellular optical element exits 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.

31. (canceled)

32. The hybrid optical system of claim 29, wherein the second opening is configured to receive a light source, and wherein light emitted by a light source located at the second opening in the upper portion of the cellular optical element exits 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.

33. (canceled)

34. The hybrid optical system of claim 25, wherein each cellular optical element in the plurality of cellular optical elements has a lower portion and an upper portion, wherein the lower portions are joined together to interconnect the plurality of cellular optical elements.

35. The hybrid optical system of claim 34, wherein the lower portions are joined together by a material, wherein the material is a same material used to construct the plurality of cellular optical elements, and wherein the material has a substantially planar shape where interconnecting the plurality of cellular optical elements.

36. (canceled)

37. (canceled)

38. (canceled)

39. The hybrid optical system of claim 25, wherein the plurality of interconnected cellular optical elements comprise a flexible optical system, wherein the flexible optical system is capable of entering a set of states, wherein the set of states comprises a substantially flat state and a substantially flexed state.

40. (canceled)

41. The hybrid optical system of claim 1, wherein the cellular optical element reflects light from a light source located at least partially within the cellular optical element.

42. The hybrid optical system of claim 41, wherein the cellular optical element reflects 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.

43. The hybrid optical system of claim 1, wherein the light control film is 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 wherein the light control film further comprises a plurality of second microstructures on the second side, the second microstructures configured to reduce glare in the off axis light distribution.

44. A lighting device, comprising:

one or more solid state light sources;

a hybrid optical system, comprising:

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 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 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.

45. (canceled)

46. The lighting device of claim 44, wherein the lighting device is located within a space defined by a ceiling tile.

47. (canceled)

48. The lighting device of claim 44, wherein the one or more light control films are 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 wherein the one or more light control films further comprise a plurality of second microstructures on the second side, the second microstructures configured to reduce glare in the off axis light distribution.