# Patent

## Title
Photoluminescent engine compartment lighting

## Abstract

An illumination apparatus for a vehicle is disclosed. The illumination apparatus comprises a photoluminescent portion disposed on an internal surface of a closure of a vehicle compartment. The illumination apparatus further includes a light source located proximate the closure. The light source is configured to emit light at a first wavelength directed toward the photoluminescent portion. The photoluminescent portion is configured to convert the first wavelength to at least a second wavelength, longer than the first wavelength, to illuminate the compartment.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation-in-part of U.S. patent application Ser. No. 14/301,635, filed Jun. 11, 2014, and entitled “PHOTOLUMINESCENT VEHICLE READING LAMP,” which is a continuation-in-part of U.S. patent application Ser. No. 14/156,869, filed on Jan. 16, 2014, entitled “VEHICLE DOME LIGHTING SYSTEM WITH PHOTOLUMINESCENT STRUCTURE,” which is a continuation-in-part of U.S. patent application Ser. No. 14/086,442, filed Nov. 21, 2013, and entitled “VEHICLE LIGHTING SYSTEM WITH PHOTOLUMINESCENT STRUCTURE.” The aforementioned related applications are hereby incorporated by reference in their entirety.


FIELD OF THE INVENTION
The present disclosure generally relates to vehicle lighting systems, and more particularly, to vehicle lighting systems employing photoluminescent structures.
BACKGROUND OF THE INVENTION
Illumination arising from photoluminescent materials offers a unique and attractive viewing experience. It is therefore desired to incorporate such photoluminescent materials in portions of vehicles to provide ambient and task lighting.
SUMMARY OF THE INVENTION
According to one aspect of the present disclosure, an illumination apparatus for a vehicle is disclosed. The illumination apparatus comprises a photoluminescent portion disposed on an internal surface of a closure of a vehicle compartment. The illumination apparatus further includes a light source located proximate the closure. The light source is configured to emit light at a first wavelength directed toward the photoluminescent portion. The photoluminescent portion is configured to convert the first wavelength to at least a second wavelength, longer than the first wavelength, to illuminate the compartment.
According to another aspect of the present disclosure, an illumination system for a vehicle engine compartment is disclosed. The illumination system includes a first photoluminescent portion disposed on an internal surface of a hood and at least a second photoluminescent portion located in an engine compartment. A light source is located proximate the hood and is configured to emit light at a first wavelength. The photoluminescent portions are configured to convert the first wavelength to at least a second wavelength, longer than the first wavelength, to illuminate the engine compartment.
According to yet another aspect of the present disclosure, a lighting system for an engine compartment is disclosed. The lighting system comprises a light source configured to emit light at a first wavelength directed toward an engine compartment. The light at the first wavelength is directed toward a plurality of photoluminescent portions corresponding to a plurality of features proximate the engine compartment. The photoluminescent portions are configured to convert the first wavelength to at least a second wavelength longer than the first wavelength to illuminate the plurality of features.
These and other aspects, objects, and features of the present disclosure will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.



BRIEF DESCRIPTION OF THE DRAWINGS
In the drawings:
FIG. 1 is a perspective view of a vehicle comprising a lighting system;
FIG. 2A illustrates a photoluminescent structure rendered as a coating;
FIG. 2B illustrates the photoluminescent structure rendered as a discrete particle;
FIG. 2C illustrates a plurality photoluminescent structures rendered as discrete particles and incorporated into a separate structure;
FIG. 3 illustrates a vehicle lighting system configured to convert a first emission of light to a second emission of light;
FIG. 4 illustrates the vehicle lighting system configured to convert a first emission of light to a plurality of emissions of light;
FIG. 5 is a perspective view of a vehicle having a lighting system configured to illuminate an engine compartment;
FIG. 6 is a perspective view of a vehicle having a lighting system configured to illuminate at least one engine component in an engine compartment; and
FIG. 7 is a perspective view of a vehicle having a lighting system configured to illuminate at least a portion of a hood of a vehicle.



DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
As required, detailed embodiments of the present disclosure are disclosed herein. However, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure 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 disclosure.
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 lighting system for a vehicle configured to illuminate at least a portion of an engine compartment. In some implementations, a light source may be configured to illuminate a first photoluminescent portion corresponding to a utility light. The light source may further be configured to illuminate a second photoluminescent portion corresponding to at least one engine compartment feature, component, fluid reservoir, and/or any other portion of the vehicle located proximate the engine compartment. In various implementations, the first photoluminescent portion may correspond to a functional lighting unit configured to illuminate the engine compartment. The second photoluminescent portion may correspond to an additional lighting unit configured to illuminate at least one engine compartment.
Referring to FIG. 1, a perspective view of a vehicle 10 is shown demonstrating a lighting system 12 configured to illuminate at least a portion of an engine compartment 14. The lighting system 12 comprises a light source 16 disposed on an interior surface 17 of a hood 18 and at least one photoluminescent portion 20. In some implementations, the at least one photoluminescent portion 20 may comprise a plurality of photoluminescent portions 22. The light source 16 is configured to output a first emission 24 corresponding to a first wavelength of light. In response to receiving the light at the first wavelength, the plurality of photoluminescent portions 22 may become illuminated and emit at least a second emission 26 having a second wavelength of light longer than the first wavelength.
The plurality of photoluminescent portions 22 may correspond to any number of features located in the engine compartment 14 and disposed on the interior surface 17 incorporating at least one photoluminescent structure. In an exemplary implementation, the lighting system 12 comprises a first photoluminescent portion 28 and a second photoluminescent portion 30. The first photoluminescent portion 28 may correspond to a utility light 32 configured to emit a high intensity light to illuminate the engine compartment 14. The second photoluminescent portion 30 may correspond to at least one feature 34 located in the engine compartment. The second photoluminescent portion 30 may be configured to illuminate the at least one feature 34 to provide an ambient glow emitted from the at least one feature 34.
Each of the plurality of photoluminescent portions 22 may incorporate one or more photoluminescent structures configured to emit a specific color in response to the excitation generated in response to the first emission 24. In some implementations, a combination of photoluminescent structures may be utilized in the photoluminescent portions 22 to output various wavelengths corresponding to different colors of light. For example, in some implementations the utility light 32 may be configured to emit a combination of red light, green light, and blue light to generate a light having a substantially white appearance. The lighting system 12 may provide various benefits including a cost-effective method for illuminating an engine compartment and incorporating ambient lighting to at least one feature 34 proximate the engine compartment 14.
Referring to FIGS. 2A-2C, a photoluminescent structure 42 is generally shown rendered as a coating (e.g. a film) capable of being applied to a vehicle fixture, a discrete particle capable of being implanted in a vehicle fixture, and a plurality of discrete particles incorporated into a separate structure capable of being applied to a vehicle fixture, respectively. The photoluminescent structure 42 may correspond to the photoluminescent portions as discussed herein, for example the first photoluminescent portion 28 and the second photoluminescent portion 30. At the most basic level, the photoluminescent structure 42 includes an energy conversion layer 44 that may be provided as a single layer or a multilayer structure, as shown through broken lines in FIGS. 2A and 2B.
The energy conversion layer 44 may include one or more photoluminescent materials having energy converting elements selected from a phosphorescent or a fluorescent material. The photoluminescent materials may be formulated to convert an inputted electromagnetic radiation into an outputted electromagnetic radiation generally having a longer wavelength and expressing a color that is not characteristic of the inputted electromagnetic radiation. The difference in wavelength between the inputted and outputted electromagnetic radiations is referred to as the Stokes shift and serves as the principle driving mechanism for an energy conversion process corresponding to a change in wavelength of light, often referred to as down conversion. In the various implementations discussed herein, each of the wavelengths of light (e.g. the first wavelength, etc.) correspond to electromagnetic radiation utilized in the conversion process.
Each of the photoluminescent portions may comprise at least one photoluminescent structure 42 comprising an energy conversion layer (e.g. conversion layer 44). The energy conversion layer 44 may be prepared by dispersing the photoluminescent material in a polymer matrix 50 to form a homogenous mixture using a variety of methods. Such methods may include preparing the energy conversion layer 44 from a formulation in a liquid carrier medium and coating the energy conversion layer 44 to a desired planar and/or non-planar substrate of a vehicle fixture. The energy conversion layer 44 coating may be deposited on a vehicle fixture by painting, screen printing, spraying, slot coating, dip coating, roller coating, and bar coating. Additionally, the energy conversion layer 44 may be prepared by methods that do not use a liquid carrier medium.
For example, a solid state solution (homogenous mixture in a dry state) of one or more photoluminescent materials may be incorporated in a polymer matrix 50 to provide the energy conversion layer 44. The polymer matrix 50 may be formed by extrusion, injection molding, compression molding, calendaring, thermoforming, etc. In instances where one or more energy conversion layers 44 are rendered as particles, the single or multi-layered energy conversion layers 44 may be implanted into a vehicle fixture or panel. When the energy conversion layer 44 includes a multilayer formulation, each layer may be sequentially coated. Additionally, the layers can be separately prepared and later laminated or embossed together to form an integral layer. The layers may also be coextruded to prepare an integrated multi-layered energy conversion structure.
Referring back to FIGS. 2A and 2B, the photoluminescent structure 42 may optionally include at least one stability layer 46 to protect the photoluminescent material contained within the energy conversion layer 44 from photolytic and thermal degradation. The stability layer 46 may be configured as a separate layer optically coupled and adhered to the energy conversion layer 44. The stability layer 46 may also be integrated with the energy conversion layer 44. The photoluminescent structure 42 may also optionally include a protective layer 48 optically coupled and adhered to the stability layer 46 or any layer or coating to protect the photoluminescent structure 42 from physical and chemical damage arising from environmental exposure.
The stability layer 46 and/or the protective layer 48 may be combined with the energy conversion layer 44 to form an integrated photoluminescent structure 42 through sequential coating or printing of each layer, or by sequential lamination or embossing. Alternatively, several layers may be combined by sequential coating, lamination, or embossing to form a substructure. The substructure may then be laminated or embossed to form the integrated photoluminescent structure 42. Once formed, the photoluminescent structure 42 may be applied to a chosen vehicle fixture.
In some implementations, the photoluminescent structure 42 may be incorporated into a vehicle fixture as one or more discrete multilayered particles as shown in FIG. 2C. The photoluminescent structure 42 may also be provided as one or more discrete multilayered particles dispersed in a polymer formulation that is subsequently applied to a vehicle fixture or panel as a contiguous structure. Additional information regarding the construction of photoluminescent structures to be utilized in at least one photoluminescent portion of a vehicle is disclosed in U.S. Pat. No. 8,232,533 to Kingsley et al., entitled “PHOTOLYTICALLY AND ENVIRONMENTALLY STABLE MULTILAYER STRUCTURE FOR HIGH EFFICIENCY ELECTROMAGNETIC ENERGY CONVERSION AND SUSTAINED SECONDARY EMISSION,” filed Nov. 8, 2011, the entire disclosure of which is incorporated herein by reference.
Referring to FIG. 3, the lighting system 12 is generally shown according to a front-lit configuration 62 to convert the first emission 24 from the light source 16 to the second emission 26. The first emission 24 comprises a first wavelength λ1, and the second emission 26 comprises a second wavelength λ2. The lighting system 12 may include the photoluminescent structure 42 rendered as a coating and applied to a substrate 68 of a vehicle fixture 70. The photoluminescent structure 42 may include the energy conversion layer 44, and in some implementations may include the stability layer 46 and/or protective layer 48. In response to the light source 16 being activated, the first emission 24 is converted from the first wavelength λ1 to the second emission 26 having at least the second wavelength λ2. The second emission 26 may comprise a plurality of wavelengths λ2, λ3, λ4 configured to emit significantly white light from the vehicle fixture 70.
In various implementations, the lighting system 14 comprises at least one energy conversion layer 44 configured to convert the first emission 24 at the first wavelength λ1 to the second emission 26 having at least the second wavelength λ2. In order to generate the plurality of wavelengths λ2, λ3, λ4, the energy conversion layer 44 may comprise a red-emitting photoluminescent material, a green-emitting photoluminescent material, and a blue-emitting photoluminescent material dispersed in the polymer matrix 50. The red, green, and blue-emitting photoluminescent materials may be combined to generate the significantly white light for the second emission 26. Further, the red, green, and blue-emitting photoluminescent materials may be utilized in a variety of proportions and combinations to control the color of the second emission 26.
Each of the photoluminescent materials may vary in output intensity, output wavelength, and peak absorption wavelengths based on a particular photochemical structure and combinations of photochemical structures utilized in the energy conversion layer 44. As an example, the second emission 26 may be changed by adjusting the wavelength of the first emission λ1 to activate the photoluminescent materials at different intensities to alter the color of the second emission 26. In addition to or alternatively to the red, green, and blue-emitting photoluminescent materials, other photoluminescent materials may be utilized alone and in various combinations to generate the second emission 26 in a wide variety of colors. In this way, the lighting system 12 may be configured for a variety of applications to provide a desired lighting color and effect for the vehicle 10.
The light source 16 may also be referred to as an excitation source and is operable to emit at least the first emission 24. The light source 16 may comprise any form of light source, for example halogen lighting, fluorescent lighting, light emitting diodes (LEDs), organic LEDs (OLEDs), polymer LEDs (PLEDs), solid state lighting or any other form of lighting configured to output the first emission 24. The first emission 24 from the light source 16 may be configured such that the first wavelength λ1 corresponds to at least one absorption wavelength of the one or more photoluminescent materials of the energy conversion layer 44. In response to receiving the light at the first wavelength λ1, the energy conversion layer 44 may be excited and output the one or more output wavelengths λ2, λ3, λ4. The first emission 24 provides an excitation source for the energy conversion layer 44 by targeting absorption wavelengths of the various photoluminescent materials utilized therein. As such, the lighting system 14 is configured to output the second emission 26 to generate a desired light intensity and color.
Though the plurality to wavelengths is referred to as the wavelengths λ2, λ3, λ4, the photoluminescent materials may be combined in various proportions, types, layers, etc. to generate a variety of colors for the second emission 26. The photoluminescent materials may also be utilized in a plurality of photoluminescent portions distributed along a path of the first emission 24 to generate any number of emissions, for example a third emission, a fourth emission, etc. The third emission may be emitted from the second photoluminescent portion 30 and the fourth emission may be emitted from a third photoluminescent portion disposed on the vehicle 10.
In an exemplary implementation, the light source 16 comprises an LED configured to emit the first wavelength λ1 which corresponds to a blue spectral color range. The blue spectral color range comprises a range of wavelengths generally expressed as blue light ( ̃440-500 nm). In some implementations, the first wavelength λ1 may also comprise wavelengths in a near ultraviolet color range ( ̃390-450 nm). In an exemplary implementation, λ1 may be approximately equal to 470 nm. In some implementations, the first wavelength λ1 may be approximately less than 500 nm such that the first wavelength of the light is not significantly visible.
The blue spectral color range and shorter wavelengths may be utilized as an excitation source for the lighting system 12 due to these wavelengths having limited perceptual acuity in the visible spectrum of the human eye. By utilizing shorter wavelengths for the first wavelength λ1, and converting the first wavelength with the conversion layer 44 to at least one longer wavelength, the lighting system 12 creates a visual effect of light originating from the photoluminescent structure 42. In this configuration, light is emitted from the photoluminescent structure 42 (e.g. the first photoluminescent portion 28, the second photoluminescent portion 30) from locations of the vehicle 10 that may be inaccessible or costly to add conventional light sources requiring electrical connections.
As discussed herein, each of the plurality of wavelengths λ2, λ3, λ4 may correspond to a significantly different spectral color range. The second wavelength λ2 may correspond to the excitation of a red-emitting photoluminescent material having a wavelength of approximately 620-750 nm. The third wavelength λ3 may correspond to the excitation of a green emitting photoluminescent material having a wavelength of approximately 526-606 nm. The fourth wavelength λ4 may correspond to a blue or blue green emitting photo luminescent material having a wavelength longer than the first wavelength λ1 and approximately 430-525 nm. Though the wavelengths λ2, λ3, λ4 are discussed herein as being utilized to generate a significantly white light, various combinations of photoluminescent materials may be utilized in the conversion layer 44 to convert the first wavelength λ1 to one or more wavelengths corresponding to a variety of colors.
Referring to FIG. 4, the light system 12 is shown in a front-lit configuration. In an exemplary implementation, the light source 16 may be configured to emit the first emission 24 toward the plurality of photoluminescent portions 82. In this example, the plurality of photoluminescent portions 22 comprises the first photoluminescent portion 28, the second photoluminescent portion 30, and a third photoluminescent portion 84. Each of the photoluminescent portions 28, 30, 84 may be configured to convert the first wavelength λ1 of the first emission 24 to one or more of the plurality of wavelengths λ2, λ3, λ4. In this way, the first emission 24 may be converted into a plurality of emissions originating from each of the photoluminescent portions 82 to generate a multicolored lighting effect.
For example, the first photoluminescent portion 28 may comprise photoluminescent materials in a conversion layer configured to generate the second emission 26. The second photoluminescent portion 30 may comprise photoluminescent materials in a conversion layer configured to generate a third emission 86. The third photoluminescent portion 84 may comprise photoluminescent materials in a conversion layer configured to generate a fourth emission 88. Similar to the energy conversion layer 44, discussed in reference to FIG. 3, photoluminescent materials configured to emit light of various colors may be utilized in a variety of proportions and combinations to control the output color of each of the second emission 66, the third emission 86, and the fourth emission 88. Based on a desired lighting effect, each of the emissions 26, 86, 88 may comprise photoluminescent material configured to emit light having substantially similar colors, or a wide variety of color combinations.
To achieve the various colors and combinations of photoluminescent materials described herein, the lighting system 12 may utilize any form of photoluminescent materials, for example phospholuminescent materials, organic and inorganic dyes, etc. For additional information regarding fabrication and utilization of photoluminescent materials to achieve various emissions, refer to U.S. Pat. No. 8,207,511 to Bortz et al., entitled “PHOTOLUMINESCENT FIBERS, COMPOSITIONS AND FABRICS MADE THEREFROM,” filed Jun. 5, 2009; U.S. Pat. No. 8,247,761 to Agrawal et al., entitled “PHOTOLUMINESCENT MARKINGS WITH FUNCTIONAL OVERLAYERS,” filed Oct. 9, 2011; U.S. Pat. No. 8,519,359 B2 to Kingsley et al., entitled “PHOTOLYTICALLY AND ENVIRONMENTALLY STABLE MULTILAYER STRUCTURE FOR HIGH EFFICIENCY ELECTROMAGNETIC ENERGY CONVERSION AND SUSTAINED SECONDARY EMISSION,” filed Mar. 4, 2013; U.S. Pat. No. 8,664,624 B2 to Kingsley et al., entitled “ILLUMINATION DELIVERY SYSTEM FOR GENERATING SUSTAINED SECONDARY EMISSION,” filed Nov. 14, 2012; U.S. Patent Publication No. 2012/0183677 to Agrawal et al., entitled “PHOTOLUMINESCENT COMPOSITIONS, METHODS OF MANUFACTURE AND NOVEL USES,” filed Mar. 29, 2012; U.S. Patent Publication No. 2014/0065442 A1 to Kingsley et al., entitled “PHOTOLUMINESCENT OBJECTS,” filed Oct. 23, 2012; and U.S. Patent Publication No. 2014/0103258 A1 to Agrawal et al., entitled “CHROMIC LUMINESCENT COMPOSITIONS AND TEXTILES,” filed Dec. 19, 2013, all of which are included herein by reference in their entirety.
Referring to FIGS. 5 and 6, the engine compartment 14 of the vehicle 10 is shown demonstrating the plurality of photoluminescent portions 22. For clarity, the first photoluminescent portion 28 disposed on the interior surface 17 is shown in reference to FIG. 5 and the plurality of photoluminescent portions 82 disposed in the engine compartment 14 are shown in FIG. 6. It shall be understood that the photoluminescent portions 82 as discussed herein may be distributed in any configuration throughout the interior surface 17 of the hood 18 and the engine compartment 14. As discussed herein, the first photoluminescent portion 28 may be configured as a utility light 32 to illuminate the engine compartment 14 for maintenance and inspection. In response to the hood 18 being oriented in an open position, a lighting control module of the vehicle 10 may be configured to activate the light source 16. Further, in response to the activation of the light source 16, the first emission 24 may be activated to emit light having the first wavelength λ1.
The light source 16 may comprise a plurality of LEDs configured to emit the first emission at the first wavelength λ1. In some implementations, the light source 16 may comprise an array of LEDs located proximate a forward portion 92 of the hood 18. By positioning the light source 16 proximate the forward portion 92, the light source 16 may experience a lower intensity of heat during operation of the vehicle 10. For example, when the hood 18 is oriented in a closed position, the light source 16 may be located proximate a radiator or cooling source of the engine such that the light source 16 is not damaged by heat radiating from an engine 94 of the vehicle 10.
As illustrated in FIG. 5, the light source 16 is configured to direct the first emission 24 substantially toward the first photoluminescent portion 28. Further, the first emission 24 may be directed downward toward the engine compartment 14 when the hood 18 is oriented in the open position. For example, the light source 16 may be connected to the interior surface 17 such that the first emission is directed substantially downward, focused centrally at the engine compartment 14. The light source 16 may further be configured to project the first emission 24 toward the first photoluminescent portion 28 and the engine compartment 14 via one or more optic lenses or devices. In this configuration, the first emission 24 at the first wavelength λ1 is emitted from the light source 16 to substantially illuminate the first photoluminescent portion 28 disposed on the hood 18 to illuminate the engine compartment 14.
Though the first emission may be directed through a substantially open volumetric space between the hood 18 and the engine compartment 14, the illumination of the light at the first wavelength λ1 may be limited perceptually. The limited visible or perceptible illumination of the first wavelength λ1 may be due to the first wavelength λ1 being in the blue or near UV spectral color ranges. Due to the limited sensitivity of the human eye to light at such short wavelengths (e.g. blue colored light), the first emission may go unnoticed to an onlooker of the lighting system 12. In this way, each of the plurality of photoluminescent portions 22 may be illuminated such that the activation source of the photoluminescent portions 22 is not apparent to provide a sophisticated ambient lighting experience.
In response to the first wavelength λ1 of the first emission 24 being received by the first photoluminescent portion 28, the energy conversion layer 44 may become excited and emit the second emission 26. As discussed previously herein, the second emission 26 may comprise a plurality of wavelengths λ2, λ3, λ4 to generate a significantly white light. The second emission 26 is generally directed toward the engine compartment 14 such that a plurality of features 96 is illuminated. The utility light 32 configuration of the first photoluminescent portion 28 may provide uniform lighting throughout the engine compartment 44.
Referring now to FIG. 6, the first emission 24 is further directed from the light source 16 downward into the engine compartment 14 to excite a conversion layer 44 in one or more photoluminescent portions 82 applied as a coating to and/or disposed in a matrix (e.g. the polymer matrix 50) of any number of the plurality of features 96. For example, the second photoluminescent portion 30 may be incorporated in an engine cover 98; the third photoluminescent portion 84 may be incorporated in an air intake 100 and a strut tower brace 102. In response to receiving the first emission 24 comprising the first wavelength λ1, each of the plurality of photoluminescent portions 82 may become excited. The excitation may cause the second photoluminescent portion 30 to emit the third emission 86 and the third photoluminescent portion 84 to emit the fourth emission 88. For clarity, various details corresponding to the first photoluminescent portion 28 are suppressed in FIG. 6.
Though the plurality of photoluminescent portions 82 are specifically discussed in reference to three exemplary portions, the plurality of photoluminescent portions 82 may corresponds to any number of portions. Each of the plurality of photoluminescent portions 82 may further include various energy conversion layers including various photoluminescent materials configured to emit a wide variety of colors in response to the first emission 24. As such, the lighting system 12 may be utilized in a variety of settings to provide the utility light 32 and/or illuminate and accent any number of features 96.
The plurality of features 96 may comprise any feature related to the vehicle 10 that may be disposed generally proximate the engine compartment 14 and the hood 18. Any of the plurality of features 96 may incorporate a photoluminescent structure applied as a coating, and/or dispersed in a material structure that may illuminate and emit light in response receiving the first wavelength λ1 of the first emission 24. Each of the photoluminescent portions 82 may be illuminated in a single color or multiple colors to provide a desired color pallet and appearance for illuminating the plurality of features 94. The photoluminescent portions 82 may further be utilized to identify one or more of the plurality of features 94 for easy identification during maintenance.
In some implementations, at least one fluid fill cap 104, dip stick, or any other feature 94 may comprise at least one photoluminescent structure 42 configured to emit an emission (e.g. the third emission 86, fourth emission 88, etc.) comprising an identifying color. The identifying color may be emitted in response to the feature 94 receiving the first emission 24. The identifying color may be configured to correspond to a color described in a vehicle user manual or maintenance instructions. In some implementations, the plurality of the photoluminescent portions 82 may correspond to a plurality of identifying colors configured to identify, categorize, and/or provide for a first feature 106 having a first color to be visually discernible from a second feature 108 having a second color. In this way, the lighting system may provide additional utility by providing decorative lighting that may serve to aid in identifying various features 94 located proximate the engine compartment 14.
Referring now to FIG. 7, a perspective view of the vehicle 10 is shown demonstrating a hood light 112 of the lighting system 12. In some implementations, a portion of the first emission 24 may be directed from the light source 16 to an outer surface 114 of the hood 18. At least a portion of the outer surface 114 of the hood 18 may include an exterior photoluminescent portion 116 disposed in a coating, paint layer, vehicle panel, or any portion of the hood 18. In such implementations, the lighting system 12 may be further configured to provide lighting for the exterior of the vehicle 10.
A portion of the first emission 24 may be directed from the light source 16 through an opening in the hood 18. In some implementations, a light pipe, tube, or any form of optic device may be configured to direct a portion of the first emission 24 from the light source 16 to the exterior photoluminescent portion 116. In response to receiving the first emission 24, the exterior photoluminescent portion 116 may become excited and illuminate the hood light 112. As discussed previously in reference the plurality of photoluminescent portions 82, the exterior photoluminescent portion 116 may be illuminated in a wide variety of colors. In order to control the light source 16 for operation of the hood light 112, the lighting control module of the vehicle 10 may be configured to selectively activate the light source 16.
The lighting system 12 as described herein provides various benefits including a cost-effective system operable to provide ambient lighting for the engine compartment 14 of the vehicle 10. The various implementations described herein, including the particular locations and configurations of each of the photoluminescent portions, may vary without departing from the spirit of the disclosure. The disclosure provides various lighting systems and methods that may improve the appearance of the engine compartment 14 and further provide light to illuminate the engine compartment 14 to improve visibility for maintenance and inspection.
For the purposes of describing and defining the present teachings, it is noted that the terms “substantially” and “approximately” are utilized herein to represent the inherent degree of uncertainty that may be attributed to any quantitative comparison, value, measurement, or other representation. The term “substantially” and “approximately” are also utilized herein to represent the degree by which a quantitative representation may vary from a stated reference without resulting in a change in the basic function of the subject matter at issue.
It is to be understood that variations and modifications can be made on the aforementioned structure without departing from the concepts of the present disclosure, 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.

## Claims

1. An illumination apparatus for a vehicle comprising:
a photoluminescent portion disposed on an internal surface of a closure of an engine vehicle compartment; and
a light source located proximate the closure, the light source configured to emit light at a first wavelength directed toward the photoluminescent portion, wherein the photoluminescent portion is configured to convert the first wavelength to at least a second wavelength longer than the first wavelength to illuminate the compartment, wherein the light source is further configured to emit the light at the first wavelength in the compartment to illuminate a second photoluminescent portion separately disposed in the compartment by converting the first wavelength to a third wavelength.

2. The illumination apparatus according to claim 1, wherein the photoluminescent portion is located proximate the light source and is configured to emit the second wavelength downward toward the compartment.

3. The illumination apparatus according to claim 1, wherein the photoluminescent portion comprises a coating disposed on a portion of a hood of the vehicle.

4. The illumination apparatus according to claim 3, wherein the light source is located on the closure proximate a fore portion of the hood to limit heat exposure of the light source from an engine.

5. The illumination apparatus according to claim 1, wherein the first wavelength is in a blue color range approximately less than 500 nm.

6. The illumination apparatus according to claim 1, wherein the second wavelength emitted from the photoluminescent portion comprises a plurality of wavelengths configured to generate a substantially white light.

7. The illumination apparatus according to claim 1, wherein the vertical closure comprises one of a hood.

8. An illumination system for a vehicle engine compartment comprising:
a first photoluminescent portion disposed on an internal surface of a hood;
at least a second photoluminescent portion located in an engine compartment separated from the first photoluminescent portion; and
a light source located proximate the hood configured to emit light at a first wavelength, wherein the photoluminescent portions are configured to convert the first wavelength to at least a second wavelength longer than the first wavelength to illuminate the engine compartment.

9. The illumination system according to claim 8, wherein the first photoluminescent portion comprises a coating sprayed on a portion of a hood insulator.

10. The illumination system according to claim 8, wherein the second photoluminescent portion comprises a feature disposed proximate the engine compartment.

11. The illumination system according to claim 8, wherein the first photoluminescent portion is configured to emit the light at the second wavelength and the second photoluminescent portion is configured to emit light at a third wavelength.

12. The illumination system according to claim 8, wherein the first photoluminescent portion is configured to emit the light at a plurality of wavelengths to generate a substantially white light.

13. The illumination system according to claim 8, wherein the second luminescent portion comprises a plurality of photoluminescent portions proximate the engine compartment including the second luminescent portion disposed on a first feature and a third luminescent portion disposed on a second feature.

14. The illumination system according to claim 8, wherein the first luminescent portion, the second luminescent portion, and the third luminescent portion are configured to emit the light at different wavelengths corresponding to different colors.

15. A lighting system for an engine compartment comprising:
a light source configured to emit light at a first wavelength directed toward an engine compartment; and
a plurality of photoluminescent portions corresponding to a plurality of separated features proximate the engine compartment, wherein the photoluminescent portions are configured to convert the first wavelength to at least a second wavelength longer than the first wavelength to illuminate the plurality of features.

16. The light system according to claim 15, wherein the plurality of photoluminescent portions comprise a first portion and a second portion, the first portion configured to convert the first wavelength of the light to the second wavelength, and the second portion configured to convert the first wavelength to a third wavelength.

17. The light system according to claim 16, wherein the first portion corresponds to a first feature disposed proximate the engine compartment and the second portion corresponds to a second feature disposed proximate the engine compartment.

18. The light system according to claim 16, wherein the second wavelength and the third wavelength comprise different colors.

19. The light system according to claim 17, wherein the second portion comprises at least one of a lettering and an emblem located on at least one of a plurality of engine components.