The present invention generally relates to vehicular lighting, and more particularly to vehicle light assemblies disposed on an exterior portion of the vehicle.
Illumination arising from the use of luminescent structures offers a unique and attractive viewing experience. It is therefore desired to implement such structures in automotive vehicles for various lighting applications.
According to one aspect of the present disclosure, a light assembly for a vehicle is disclosed. The light assembly includes a housing and a lens. A light source is disposed between the housing and lens. A bulb shield is disposed between the light source and the lens. A peripheral portion of the bulb shield has a first optical transmittance and a central region of the bulb shield has a second optical transmittance.
According to another aspect of the present disclosure, a light assembly is disclosed. The light assembly includes a housing and a lens. A light source is disposed between the housing and lens. A bulb shield is disposed between the light source and the lens. The bulb shield is light transmissive. A luminescent structure is disposed on the bulb shield configured to luminesce in response to receiving light from the light source.
According to yet another aspect of the present disclosure, a light assembly for a vehicle is disclosed. The light assembly includes a housing and a lens. A light source is disposed between the housing and lens. A bulb shield is disposed between the light source and the lens. The bulb shield is light transmissive. A light transmissive support structure is integrally formed with the bulb shield.
These and other aspects, objects, and features of the present invention will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.
In the drawings:
For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as oriented in
As required, detailed embodiments of the present invention are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to a detailed design and some schematics may be exaggerated or minimized to show function overview. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
In this document, relational terms, such as first and second, top and bottom, and the like, are used solely to distinguish one entity or action from another entity or action, without necessarily requiring or implying any actual such relationship or order between such entities or actions. The terms “comprises,” “comprising,” or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. An element proceeded by “comprises . . . a” does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.
As used herein, the term “and/or,” when used in a list of two or more items, means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.
The following disclosure describes a light assembly for a vehicle. In various embodiments, the light assembly utilizes light generated by a headlamp assembly to excite one or more phosphorescent and/or luminescent structures. The one or more luminescent structures may be configured to convert excitation light received from the associated light source and re-emit the light at a different wavelength typically found in the visible spectrum.
Referring to
At the most basic level, a given luminescent structure 10 includes an energy conversion layer 16 that may include one or more sublayers, which are exemplarily shown through broken lines in
Light emitted by a light source 40 (
The energy conversion layer 16 may be prepared by dispersing the luminescent material 18 in a polymer matrix to form a homogenous mixture using a variety of methods. Such methods may include preparing the energy conversion layer 16 from a formulation in a liquid carrier support medium 14 and coating the energy conversion layer 16 to a desired substrate 12. The energy conversion layer 16 may be applied to a substrate 12 by painting, screen-printing, spraying, slot coating, dip coating, roller coating, and bar coating. Alternatively, the energy conversion layer 16 may be prepared by methods that do not use a liquid carrier support medium 14. For example, the energy conversion layer 16 may be rendered by dispersing the luminescent material 18 into a solid-state solution (homogenous mixture in a dry state) that may be incorporated in a polymer matrix, which may be formed by extrusion, injection molding, compression molding, calendaring, thermoforming, etc. The energy conversion layer 16 may then be integrated into a substrate 12 using any methods known to those skilled in the art. When the energy conversion layer 16 includes sublayers, each sublayer may be sequentially coated to form the energy conversion layer 16. Alternatively, the sublayers can be separately prepared and later laminated or embossed together to form the energy conversion layer 16. Alternatively still, the energy conversion layer 16 may be formed by coextruding the sublayers.
In various embodiments, the converted light 26 that has been down converted or up converted may be used to excite other luminescent material(s) 18 found in the energy conversion layer 16. The process of using the converted light 26 outputted from one luminescent material 18 to excite another, and so on, is generally known as an energy cascade and may serve as an alternative for achieving various color expressions. With respect to either conversion principle, the difference in wavelength between the excitation light 24 and the converted light 26 is known as the Stokes shift and serves as the principal driving mechanism for an energy conversion process corresponding to a change in wavelength of light. In the various embodiments discussed herein, each of the luminescent structures 10 may operate under either conversion principle.
Referring back to
Additional information regarding the construction of luminescent structures 10 is disclosed in U.S. Pat. No. 8,232,533 to Kingsley et al., the entire disclosure of which is incorporated herein by reference. For additional information regarding fabrication and utilization of luminescent materials to achieve various light emissions, refer to U.S. Pat. No. 8,207,511 to Bortz et al., U.S. Pat. No. 8,247,761 to Agrawal et al., U.S. Pat. No. 8,519,359 to Kingsley et al., U.S. Pat. No. 8,664,624 to Kingsley et al., U.S. Patent Publication No. 2012/0183677 to Agrawal et al., U.S. Pat. No. 9,057,021 to Kingsley et al., and U.S. Pat. No. 8,846,184 to Agrawal et al., all of which are incorporated herein by reference in its entirety.
According to various embodiments, the luminescent material 18 may include organic or inorganic fluorescent dyes including rylenes, xanthenes, porphyrins, and phthalocyanines. Additionally, or alternatively, the luminescent material 18 may include phosphors from the group of Ce-doped garnets such as YAG:Ce and may be a short-persistence luminescent material 18. For example, an emission by Ce3+ is based on an electronic energy transition from 4D1 to 4f1 as a parity allowed transition. As a result of this, a difference in energy between the light absorption and the light emission by Ce3+ is small, and the luminescent level of Ce3+ has an ultra-short lifespan, or decay time, of 10−8 to 10−7 seconds (10 to 100 nanoseconds). The decay time may be defined as the time between the end of excitation from the excitation light 24 and the moment when the light intensity of the converted light 26 emitted from the luminescent structure 10 drops below a minimum visibility of 0.32 mcd/m2. A visibility of 0.32 mcd/m2 is roughly 100 times the sensitivity of the dark-adapted human eye, which corresponds to a base level of illumination commonly used by persons of ordinary skill in the art.
According to various embodiments, a Ce3+ garnet may be utilized, which has a peak excitation spectrum that may reside in a shorter wavelength range than that of conventional YAG:Ce-type phosphors. Accordingly, Ce3+ has short-persistence characteristics such that its decay time may be 100 milliseconds or less. Therefore, in various embodiments, the rare earth aluminum garnet type Ce phosphor may serve as the luminescent material 18 with ultra-short-persistence characteristics, which can emit the converted light 26 by absorbing purple to blue excitation light 24 emitted from the light source 40. According to various embodiments, a ZnS:Ag phosphor may be used to create a blue-converted light 26. A ZnS:Cu phosphor may be utilized to create a yellowish-green converted light 26. A Y2O2S:Eu phosphor may be used to create red converted light 26. Moreover, the aforementioned phosphorescent materials may be combined to form a wide range of colors, including white light. It will be understood that any short-persistence luminescent material known in the art may be utilized without departing from the teachings provided herein. Additional information regarding the production of short-persistence luminescent materials is disclosed in U.S. Pat. No. 8,163,201 to Kingsley et al., the entire disclosure of which is incorporated herein by reference.
Additionally, or alternatively, the luminescent material 18, according to various embodiments, disposed within the luminescent structure 10 may include a long-persistence luminescent material 18 that emits the converted light 26, once charged by the excitation light 24. The excitation light 24 may be emitted from any excitation source (e.g., any natural light source, such as the sun, and/or any artificial light source 40). The long-persistence luminescent material 18 may be defined as having a long decay time due to its ability to store the excitation light 24 and release the converted light 26 gradually, for a period of several minutes or hours, once the excitation light 24 is no longer present.
The long-persistence luminescent material 18, according to various embodiments, may be operable to emit light at or above an intensity of 0.32 mcd/m2 after a period of 10 minutes. Additionally, the long-persistence luminescent material 18 may be operable to emit light above or at an intensity of 0.32 mcd/m2 after a period of 30 minutes and, in various embodiments, for a period substantially longer than 60 minutes (e.g., the period may extend 24 hours or longer, and in some instances, the period may extend 48 hours). Accordingly, the long-persistence luminescent material 18 may continually illuminate in response to excitation from any light source 40 that emit the excitation light 24, including, but not limited to, natural light source (e.g., the sun) and/or any artificial light source 40. The periodic absorption of the excitation light 24 from any excitation source may provide for a substantially sustained charge of the long-persistence luminescent material 18 to provide for consistent passive illumination. In various embodiments, a light sensor 80 may monitor the illumination intensity of the luminescent structure 10 and actuate an excitation source when the illumination intensity falls below 0.32 mcd/m2, or any other predefined intensity level.
The long-persistence luminescent material 18 may correspond to alkaline earth aluminates and silicates, for example, doped di-silicates, or any other compound that is capable of emitting light for a period of time once the excitation light 24 is no longer present. The long-persistence luminescent material 18 may be doped with one or more ions, which may correspond to rare earth elements, for example, Eu2+, Tb3+, and/or Dy3. According to one non-limiting exemplary embodiment, the luminescent structure 10 includes a phosphorescent material in the range of about 30% to about 55%, a liquid carrier medium in the range of about 25% to about 55%, a polymeric resin in the range of about 15% to about 35%, a stabilizing additive in the range of about 0.25% to about 20%, and performance-enhancing additives in the range of about 0% to about 5%, each based on the weight of the formulation.
The luminescent structure 10, according to various embodiments, may be a translucent white color, and in some instances reflective, when unilluminated. Once the luminescent structure 10 receives the excitation light 24 of a particular wavelength, the luminescent structure 10 may emit any color light (e.g., blue or red) therefrom at any desired brightness. According to various embodiments, a blue emitting phosphorescent material may have the structure Li2ZnGeO4 and may be prepared by a high-temperature solid-state reaction method or through any other practicable method and/or process. The afterglow may last for a duration of 2-8 hours and may originate from the excitation light 24 and d-d transitions of Mn2+ ions.
According to an alternate non-limiting exemplary embodiment, 100 parts of a commercial solvent-borne polyurethane, such as Mace resin 107-268, having 50% solids polyurethane in toluene/isopropanol, 125 parts of a blue-green long-persistence phosphor, such as Performance Indicator PI-BG20, and 12.5 parts of a dye solution containing 0.1% Lumogen Yellow F083 in dioxolane may be blended to yield a low rare earth mineral luminescent structure 10. It will be understood that the compositions provided herein are non-limiting examples. Thus, any phosphor known in the art may be utilized within the luminescent structure 10 without departing from the teachings provided herein. Moreover, it is contemplated that any long-persistence phosphor known in the art may also be utilized without departing from the teachings provided herein.
Additional information regarding the production of long-persistence luminescent materials is disclosed in U.S. Pat. No. 8,163,201 to Agrawal et al., the entire disclosure of which is incorporated herein by reference. For additional information regarding long-persistence phosphorescent structures, refer to U.S. Pat. No. 6,953,536 to Yen et al., U.S. Pat. No. 6,117,362 to Yen et al., and U.S. Pat. No. 8,952,341 to Kingsley et al., all of which are incorporated herein by reference in their entirety.
With further reference to
The quantum dot embodiments of the luminescent material 18 may be configured to emit light in response to the excitation light 24. According to various embodiments, the quantum dots may be configured to emit light by up-converting excitation light 24. In up-conversion processes, two or more photons of a longer wavelength excitation light 24 are absorbed. Once absorbed, the quantum dots may emit one or more photons having a shorter wavelength than the wavelengths of the excitation light 24. According to various embodiments, the excitation light 24 may be in the infrared (IR) light spectrum. In such embodiments, the excitation light 24 may have a wavelength of between about 800 nm and about 1000 nm. In one exemplary embodiment, the excitation light 24 may have a wavelength of between 900 and 1000 nm, such as 980 nm. A wavelength between 900 and 1000 nm is chosen since red, blue and green emitting colloidal quantum dots of these species can efficiently absorb this wavelength of excitation light 24. This wavelength of light may be readily emitted from heated vehicle components (e.g., a light source 40 (
Referring to
Referring to
The light assembly 30 also includes a light source 40, such as an incandescent bulb, halogen bulb, high-intensity discharge lamps (HID), and/or a light emitting diode (LED) for example, for illuminating outwardly from the vehicle 28. The light source 40 is mounted to the housing 36 and may be spaced apart from the reflector 38 for providing illumination that is reflected from the reflector 38 and out of the light assembly 30. The light source 40 generally radiates excitation light 24 omnidirectionally. Accordingly, the light source 40 is provided at a focal point of the parabolic reflector 38 such that omnidirectional light from the light source 40 is reflected from the reflector 38 and is focused into a forward path of illumination.
The light assembly 30 also includes a lens 42 for partially, or fully, enclosing the housing 36 and protecting the light source 40. The lens 42 is generally transparent and/or translucent and may be formed from a polymer, an elastomer, any other transparent or translucent material, and/or combinations thereof. The light assembly 30 is also provided with a bulb shield 44, which may prevent glare light from exiting the light assembly 30. The bulb shield 44 has a peripheral region 46 and a central region 48 that is disposed proximately to the light source 40 and is mounted to the housing 36 by a support structure 50. The light source 40 generally emits light rays omnidirectionally from the light source 40. The bulb shield 44 is configured to prevent some excitation light 24 emitted from the light source 40 from unimpeded exit through the lens 42. The bulb shield 44 may additionally assist in forming a desired light cone as the excitation light 24 exits the lens 42. It will be appreciated that the illumination patterns described herein may form light cones, which may be described as a surface in space-time, represented as a cone in three dimensions, including the points from which a light signal would reach a given point (at the apex) simultaneously, and that therefore appear simultaneous to an observer at the apex. Moreover, the light cone may be of any geometry without departing from the scope of the present disclosure.
While blocking the glare excitation light 24, the bulb shield 44 may absorb heat, which may be generated by one or more light source 40 within the light assembly 30, such as the light source 40. The radial symmetry of the peripheral region 46 of the bulb shield 44 results in a distribution of blocked glare light and therefore a distribution of heat to the bulb shield 44. To reduce heat absorption within the bulb shield 44, the bulb shield 44 may be formed from a heat-resistant elastomeric material such as PVC, latex, silicone, heat-resistant rubber (and its derivative materials), heat-resistant engineering polymers, polyalkylene-terephthalate, isophthalate, and/or copolyesters. For example, the bulb shield 44 may be formed from a material containing silicone due to its thermal stability over a wide temperature range.
Referring to
In various embodiments, the bulb shield 44 of the light assembly 30 may have portions thereof that are further from the light source 40 than other portions. Therefore, while the bulb shield 44 blocks glare light, the bulb shield 44 may absorb heat unevenly. For example, the peripheral region 46 of the bulb shield 44 is illustrated as a polygon, such as a parallelogram that extends away from the light source 40, which may assist in dissipation of heat into the ambient air within a cavity 58 that is defined between the housing 36 and the lens 42. The peripheral region 46 may have rounded corners 60 (
According to various embodiments, the peripheral region 46 the bulb shield 44 may have a first optical transmittance and the central region 48 of the bulb shield 44 may have a second optical transmittance. According to various embodiments, the first optical transmittance may be lower than the second optical transmittance. Moreover, the first and/or second optical transmittance may be less than 20% transmittance, less than 10% transmittance, or less, meaning that the peripheral region 46 and/or the central region 48 may be nearly opaque, or fully opaque. The support structure 50 may also be formed from a transparent and/or translucent material having a third optical transmittance. Due to the transparent and/or translucent nature of the peripheral region 46, the central region 48, and/or the support structure 50, in various embodiments, the bulb shield 44 may be concealed and/or not readily visible to an onlooker of the vehicle 28.
The peripheral region 46 may have a lower optical transmittance due to a variance in the material utilized to form the peripheral region 46 and/or a decorative material 62 may disposed on and/or within the bulb shield 44. The decorative material 62 may include a material that is configured to control or modify an appearance of the bulb shield 44, and/or any other portion of the light assembly 30. For example, the decorative material 62 may be configured to confer a white appearance, or any other desired color or finish, to portions of light assembly 30, such as the lens 42. The decorative material 62 can be disposed on the bulb shield 44, and/or any other portion of the light assembly 30, through any method known in the art, including, but not limited to, sputter deposition, vacuum deposition (vacuum evaporation coating), electroplating, adhesives and/or printing onto a component of the light assembly 30. The decorative material 62 may be chosen from a wide range of materials and/or colors, including, but not limited to, silver, chrome, copper, bronze, gold, or any other metallic surface. Additionally, an imitator of any metallic material may also be utilized without departing from the teachings provided herein. In various embodiments, the decorative material 62 may be tinted any color to complement the vehicle 28.
In various embodiments, the decorative material 62, the peripheral region 46, the central region 48, and/or the support structure 50 may have a textured or grained surface. The grained surface may be produced by laser etching the bulb shield 44 and may provide for the light assembly 30 to have a varied or common appearance with proximately disposed components of the vehicle 28.
With further reference to
While blocking some of the light produced by the light source 40, assisting in preventing glare to oncoming vehicles, the bulb shield 44 absorbs heat and/or IR light. The IR light may have a wavelength of between about 800 nm and about 1000 nm, which may be readily emitted from heated headlamp components (e.g., the light source 40 and/or the bulb shield 44). In operation, the light source 40 emits excitation light 24, which increases a cavity temperature within the cavity 58. When the bulb shield 44, or any other component of the light assembly 30, reaches a temperature sufficiently high to begin releasing thermal radiation as excitation light 24, the first and/or second luminescent structure 10a, 10b is excited and luminesces in response to receiving the excitation light 24. The converted light 26, or luminescence, may be visible to a human eye.
As illustrated in
In various embodiments, the light source 40 may pulse light at predefined times, such as every five minutes, to re-excite the first and/or second luminescent structures 10a, 10b such that the first and/or second luminescent structures 10a, 10b continue to emit light above a predefined intensity. The light source 40 may pulse at any frequency without departing from the teachings provided herein.
Referring again to
According to various embodiments, the bulb shield 44 may be formed through a multi-shot molding process. Due to fabrication and assembly steps being performed inside a mold, molded multi-material objects may allow reduction in assembly operations and production cycle times. Furthermore, the product quality can be improved, and the possibility of manufacturing defects, and total manufacturing costs can be reduced. In multi-material injection molding, multiple different materials are injected into a multi-stage mold. The sections of the mold that are not to be filled during a molding stage are temporarily blocked. After the first injected material sets, then one or more blocked portions of the mold are opened and the next material is injected. This process continues until the required multi-material part is created.
According to various embodiments, a multi-shot molding process is used to create the bulb shield 44. Initially, the central region 48 of the bulb shield 44 may be formed through a first injection-molding step, or through successive steps, if necessary. The peripheral region 46 of the bulb shield 44 may then be formed in a successive step. Lastly, the support structure 50 may be formed with the peripheral region 46 or in a successive step. In alternative embodiments, additional components may be added during one of the injection steps, or successively added in additional injections to adhere more components to the bulb shield 44.
A variety of advantages may be derived from the use of the present disclosure. For example, use of the light assembly disclosed herein provides a unique aesthetic appearance to the vehicle thereby increasing the value of the vehicle to a customer. Moreover, the light assembly disclosed may allow for light emitted from a headlamp to be used in a more efficient manner. The light assembly provided herein may also assist in heat dissipation within the headlamp assembly. The light assembly may be manufactured at low costs when compared to standard vehicle headlamp assemblies.
According to various embodiments, a light assembly for a vehicle is provided herein. The light assembly includes a housing and a lens. A light source is disposed between the housing and lens. A bulb shield is disposed between the light source and the lens. A peripheral portion of the bulb shield has a first optical transmittance and a central region of the bulb shield has a second optical transmittance. The light assembly may be configured as a vehicle light assembly. Embodiments of the light assembly can include any one or a combination of the following features:
Moreover, the light assembly may be manufactured by coupling a housing and a lens; positioning a light source between the housing and the lens; disposing a bulb shield disposed between the light source and the lens; forming a peripheral portion of the bulb shield having a first optical transmittance; and forming a central region of the bulb shield having a second optical transmittance.
It will be understood by one having ordinary skill in the art that construction of the described invention and other components is not limited to any specific material. Other exemplary embodiments of the invention disclosed herein may be formed from a wide variety of materials, unless described otherwise herein.
For purposes of this disclosure, the term “coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated.
Furthermore, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “operably connected” or “operably coupled” to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “operably couplable” to each other to achieve the desired functionality. Some examples of operably couplable include, but are not limited, to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.
It is also important to note that the construction and arrangement of the elements of the invention as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations.
It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present invention. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting.
It is also to be understood that variations and modifications can be made on the aforementioned structures and methods without departing from the concepts of the present invention, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.