Vehicle components utilizing infrared reflective detectable layer and infrared transmissive decorative layer

A vehicle body panel includes a substrate defining an exterior surface. A detectable layer is positioned on the exterior surface and is configured to interact with a first band of an electromagnetic spectrum. A decorative layer is positioned on the detectable layer and is configured to reflect a portion of a second band of the electromagnetic spectrum and transmit the first portion of the electromagnetic spectrum. A top layer is positioned on the decorative layer and is configured to transmit the first and second band of the electromagnetic spectrum.

FIELD OF THE INVENTION

The present disclosure generally relates to detectable layers, and more particularly, to vehicle components having infrared and near-infrared detectable layers.

BACKGROUND OF THE INVENTION

Autonomous vehicles sense the world around them using a variety of sensors. One such sensor may include a light detection and ranging (LIDAR) system that measures distance by illuminating a target with laser light. Such laser light may exist in the near-infrared and/or infrared wavelength band of the electromagnetic spectrum. In instances where the intended target has a high absorption, or low reflectance, of the wavelength used by the LIDAR system, detection of targets may prove difficult due to the lack of returned light from the target.

SUMMARY OF THE INVENTION

According to one aspect of the present disclosure, a vehicle body panel includes a substrate defining an exterior surface. A detectable layer is positioned on the exterior surface and is configured to interact with a first band of an electromagnetic spectrum. A decorative layer is positioned on the detectable layer and is configured to reflect a portion of a second band of the electromagnetic spectrum and transmit the first portion of the electromagnetic spectrum. A top layer is positioned on the decorative layer and is configured to transmit the first and second bands of the electromagnetic spectrum.

According to another aspect of the present disclosure, a vehicle body panel includes a substrate. A detectable layer is positioned on the substrate and is configured to reflect a band of an electromagnetic spectrum. A decorative layer includes a pigment and is positioned on the detectable layer. The decorative layer and the pigment are configured to transmit the band of the electromagnetic spectrum.

According to yet another aspect of the present disclosure, a vehicle includes a substrate. A detectable layer is configured as an indicium and is positioned on the substrate. The detectable layer is configured to reflect a non-visible band of the electromagnetic spectrum. A decorative layer is positioned over the detectable layer and is configured to transmit the non-visible band of the electromagnetic spectrum.

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. It will also be understood that features of each embodiment disclosed herein may be used in conjunction with, or as a replacement for, features of the other embodiments.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now toFIGS. 1-4B, reference numeral10generally designates a vehicle. The vehicle10includes a plurality of body panels14positioned around an exterior of the vehicle10. Each of the body panels14may include a substrate18which defines an interior surface18A and an exterior surface18B. It will be understood that the interior surface18A may be an inboard surface generally pointing towards an interior of the vehicle10and the exterior surface18B may be an outboard surface generally facing outward from the vehicle10. Positioned on the exterior surface18B of the substrate18is a detectable layer22. It will be understood that the detectable layer22may additionally or alternatively be positioned on the interior surface18A of the substrate18. According to various examples, the detectable layer22may be configured to interact (e.g., reflect, fluoresce in response to, absorb and/or transmit) with one or more bands of an electromagnetic spectrum. A decorative layer26is positioned on the detectable layer22. According to various examples, the decorative layer26is configured to interact (e.g., reflect, fluoresce in response to, absorb and/or transmit) one or more bands of the electromagnetic spectrum. A top layer30is positioned over the decorative layer26. The top layer30may be configured to interact (e.g., reflect, fluoresce in response to, absorb and/or transmit) with one or more bands of the electromagnetic spectrum.

Referring now toFIG. 1, the vehicle10in the depicted example is a car, but it will be understood that the disclosure may equally be applied to trucks, vans, motorcycles, construction equipment and the like without departing from the teachings provided herein. As explained above, the vehicle10includes a plurality of body panels14positioned around the exterior of the vehicle10. It will be understood that although described in connection with exterior components, the description provided below may equally be applied to interior components (e.g., trim components, fascia, etc.). Examples of the body panels14of the vehicle10may include rear quarter panels38, a lift gate42, bumpers46, a roof50, doors54, front quarter panels58, pillars62, as well as other body panels14positioned around the vehicle10. It will be understood that this disclosure may also apply to transparencies around the vehicle10such as windows66and light assemblies70. Further, the disclosure may equally be applied to license plates, stickers, or appliques positioned on the vehicle10.

Referring now toFIG. 2, the body panels14have a layered structure including the substrate18, the detectable layer22positioned on the exterior surface18A of the substrate18, the decorative layer26positioned on top of the detectable layer22and the top layer30positioned on top of the decorative layer26. It will be understood that other orders of the layers22,26,30may be implemented without departing from the disclosure provided herein.

The top layer30may be configured to interact (e.g., reflect, fluoresce in response to, absorb and/or transmit) one or more bands of the electromagnetic spectrum. According to various examples, the top layer30may be configured to transmit greater than about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or greater than about 99% of the visible, near-infrared, and/or infrared bands of the electromagnetic spectrum. According to various examples, the top layer30may be known as, and configured to function as, a “clear coat” for the body panel14. The top layer30may provide protection from physical, chemical and/or environmental damage which the body panel14may be exposed to. The top layer30may be composed of a polymeric binder including one or more resins. The composition of the top layer30can further include one or more additives including, but not limited to, stabilizers (e.g., hindered amine light stabilizers or ultraviolet light absorbers), rheology control additives, flow control additives and other additives to achieve certain appearance and/or durability characteristics. Non-limiting examples of top layer30compositions that are suitable include thermally cured one-component solvent-borne clear coats, such as acrylic-melamine clear coats, epoxy-acid clear coats, polyester clear coats, alkyd clear coats and/or combinations thereof. In another example, the top layer30composition may include thermally cured two-component solvent-borne clear coats such as polyurethane clear coats, epoxy-acid clear coats, epoxy-thiol clear coats, thiourethane clear coats and/or combinations thereof. In another example, the top layer30composition may include radiation cured solvent-borne clear coats such as urethane acrylate clear coats, epoxy acrylate clear coats, thiourethane clear coats, epoxy-acid clear coats, urethane clear coats, ester-acrylate clear coats and/or combinations thereof. In another example, the top layer30composition may include thermally cured powder clear coats such as epoxy clear coats, polyester clear coats, acrylic clear coats, urethane clear coats and/or combinations thereof. In another example, the top layer30composition may include and thermally cured water-borne clear coats, such as polyurethane clear coats. It will be understood that any of the disclosed compositions for the top layer30may be utilized (e.g., mixed, layered, etc.) with any other compositions disclosed for the top layer30.

The decorative layer26is positioned below the top layer30. The top layer30may cover all or a portion of the decorative layer26. One or more adhesion layers may be positioned between the top layer30and the decorative layer26to facilitate or increase adhesion between the layers30,26. The decorative layer26may have a thickness of between about 10 μm and about 30 μm. The decorative layer26may be referred to as a “base coat” and/or a “paint.” In examples where the decorative layer26is a paint or base coat, the decorative layer26may include additives26A such as pigments, particles, flakes or other additives which may provide a desired appearance to the decorative layer26. The decorative layer26may provide aesthetically pleasing color and effects by reflecting and/or scattering at least one band of the electromagnetic spectrum. For example, the decorative layer26, in paint examples, may provide a perceived color to an onlooker by reflecting a portion (e.g., a specific color) of the visible band of the electromagnetic spectrum. The reflected portion of the electromagnetic band may be due to one or more pigments (e.g., the additives26A) disposed within a resinous binder. Exemplary compositions of pigments may include Perylene compounds such as Paliogen® and Lumogen®. The inclusion of one or more flakes and particles (e.g., the additives26A) may provide a metallic reflection and/or scattering of incident light on the decorative layer26. The flakes and/or particles may be composed of metals (e.g., aluminum, steel, etc.) to provide an iridescent or sparkling appearance.

According to various examples, the additives26A within the decorative layer26may be configured to interact (e.g., transmit, absorb, and/or reflect) one or more bands of the electromagnetic spectrum. Further, multiple different additives26A may be used, not all of which may interact with the same bands of the electromagnetic spectrum. Further, the additives26A may be configured to interact differently with different wavelength bands of the electromagnetic spectrum than the detectable layer22and/or the top layer30. For example, the additives26A may be configured to reflect a first band of the electromagnetic spectrum (e.g., visible light) while remaining transparent to a second band of the electromagnetic spectrum (e.g., near infrared and/or infrared light). The additives26A may have a transparency to near infrared and/or infrared light of greater than about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or greater than about 99%. The additives26A may reflect greater than about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or greater than about 99% of visible light or specific bands (e.g., colors) of the visible light.

The detectable layer22is positioned between the exterior surface18B of the substrate18and the decorative layer26. One or more adhesion layers may be positioned between the decorative layer26and the detectable layer22, or between the detectable layer22and the exterior surface18B, to facilitate or increase adhesion. The detectable layer22is configured to interact (e.g., reflect, fluoresce, absorb, transmit) with one or more wavelength bands of the electromagnetic spectrum. According to one example, the detectable layer22is configured to allow detection of the vehicle10by LIDAR systems by reflecting and/or emitting light having a wavelength detectable by the LIDAR systems. According to various examples, the detectable layer22is configured to reflect, absorb and/or fluoresce light in the infrared band (e.g., light having a wavelength of between about 700 nm to about 1 mm) of the electromagnetic spectrum, and more particularly, the near infrared band (e.g., light having a wavelength of between about 700 nm to about 1550 nm). LIDAR systems may utilize lasers or light emission sources which emit light having a wavelength of about 905 and/or 1550 nm. In reflective examples of the detectable layer22, the detectable layer22may be configured to reflect equal to or greater than about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 99% of light (e.g., of the near-infrared band) falling on the detectable layer22. The detectable layer22may be partially, substantially or fully transparent to light within the visible wavelength band of light (e.g., light having a wavelength of between about 390 nm to about 700 nm). For example, the detectable layer22may have a transparency to light in the visible wavelength band equal to or greater than about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 99%. Alternatively, the detectable layer22may be configured to reflect and/or absorb greater than about 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90% or 99% of visible light. The detectable layer22may have a thickness of between about 12 μm and about 75 μm, or between about 25 μm and about 50 μm.

The detectable layer22may be positioned and/or applied on the exterior surface18B of the substrate18in a variety of manners. For example, the detectable layer22may be applied as a coating, film, additional substrate, veneer, glaze, layer and/or covering without departing from the spirit of this disclosure. The detectable layer22may fully cover the substrate18, or may be applied in a striped, stippled or other pattern. Further, the type of application may change across a body panel14and from body panel14to body panel14. The composition, application method and/or thickness (e.g., and therefore the level of interaction with bands of the electromagnetic spectrum) of the detectable layer22may vary across the detectable layer22. For example, the composition, application method and/or thickness of the detectable layer22may be altered to form an indicium80or multiple indicia80. In a first example, the detectable layer22may be applied or laid down (e.g., though an ink jet process, pad printing, screen printing, etc.) on the exterior surface18B in the shape or form of the indicium80. For example, stripes of the detectable layer22, separated by portions of the exterior surface18B not including the detectable layer22, may form the indicium80. In another example, the detectable layer22may be applied such that the detectable layer22includes a first portion22A and a second portion22B. The first and second portions22A,22B may cooperate to form the indicium80. The indicium80may cover a portion, or the entire body panel14. The first and second portions22A,22B may differ in thickness, composition, application method and/or any other manner which may affect the interaction with the electromagnetic spectrum. For example, the second portion22B may have a higher reflectivity to near-infrared and/or infrared bands of the electromagnetic spectrum as compared to the first portion22A. As such, the detectable layer22, utilizing the first and second portions22A,22B may form the indicium80as only visible to a sensing system (e.g., LIDAR) and not to un-aided persons viewing the body panel14. The indicium80may be alphanumeric text, pictures, symbols, patterns, stippling, striping, numbers, machine readable codes (e.g., bar codes, QR codes, etc.), or other indicium80configured to confer information. For example, the indicium80may indicate the position of the substrate18on the vehicle10. Such a use may be advantageous in allowing LIDAR systems to quickly determine which portion of the vehicle10is being sensed.

According to a first reflective example of the detectable layer22, the detectable layer22is configured as a plurality of particles (e.g., a reflective component) or pigments disposed in a coating or binder. The particles or pigments may be configured to selectively reflect radiation at one wavelength, but may be transparent at other wavelengths as explained above. The particles may include a dielectric material. In a specific example, the dielectric particles may include TiO2. According to some examples, the dielectric particles may include one or more dopants disposed within a matrix of the dielectric particles. The dopants may include metals such as gold, niobium, copper or combinations thereof. The dopants may be present within the dielectric particles at a concentration of less than about 5%, 4%, 3%, 2%, 1% or less than about 0.1%. Use of the dopants within the dielectric particles may increase the reflectivity of the dielectric particles at 1550 nm from about 30% to 65%. For example,FIG. 3A, depicts the reflectance vs. wavelength of undoped TiO2sample and a gold doped TiO2sample (e.g., the detectable layer22). As can be seen, the reflectivity of the gold doped TiO2sample is increased relative to that of the undoped sample. The particles may have a volume fraction within the binder of between about 0.5% and about 20%, or between about 1% and about 10%, or between about 4% and about 6%. In a specific example, the particles may have a volume fraction within the binder of about 5%.

According to a second reflective example of the detectable layer22, the detectable layer22may include a stack of thin layers of materials with different refractive indices (e.g., a high refractive index material and a low refractive index material) on top of each other (e.g., a first material layer and a second material layer). In a specific example, the thin layers of material may be dielectrics. The thin layers of material may be arranged in a dielectric stack (i.e., a grouping of the first and second material layers based on physical properties). The detectable layer22may have one, two or more stacks of the first and second dielectric layers, each stack varying properties such as thickness and refractive index of the layers. This example of the detectable layer22may be referred to as a dielectric mirror. Using such an example, the wavelength at which the detectable layer22is reflective can be tuned by varying the thickness and composition of the alternating layers of high and low refractive index materials. The sharpness of the reflectivity window (i.e., a wavelength band at which the detectable layer22is reflective) can be controlled by the number of layers present in the detectable layer22. Exemplary dielectric materials include SiO2, Ta2O5, NbO5, TiO2, HfO2, MgF2and combinations thereof. The thickness of the dielectric layers may each be between about 5 nm and about 200 nm. In some examples, the thickness of the dielectric layers may be different than one another and may vary. In some examples, the choice of which dielectric material to use may be based on the refractive index of the material in order to increase or decrease the reflectivity of the detectable layer22. In various examples, high refractive index materials may have indices greater than about 1.9, greater than about 2.1, or greater than about 2.4. In various examples, low index of refraction materials may have refractive indices of less than about 1.5, less than about 1.4, or less than about 1.3. Examples of the detectable layer22utilizing dielectric mirrors may include a scattering structure (e.g., a roughening of the top layer30, scattering particles in the detectable layer22and/or decorative layer26, etc.) configured to diffusely reflect various wavelengths and minimize specular reflection.

In examples of the detectable layer22utilizing the alternating stack of high and low refractive index materials, the stack of high and low refractive index materials may be configured as a plurality of particles (e.g., the reflective component) disposed within a binder, as explained above in connection with the first example of the detectable layer22. The stacks of alternating thin layers of materials with different refractive indices may be formed by thin film deposition. The stacks can be deposited by pyrolytic vapor deposition, chemical vapor deposition, sputtering or layer-by-layer (LBL) deposition. The stacks of alternating thin layers of materials may be produced by creating the thin films on flexible substrates, releasing the films from the substrate, and grinding the material into small flakes or particles for dispersion in binders and coatings, as explained above in connection with the first example of the detectable layer22. The particles may have a volume fraction within the binder of between about 0.5% and about 20%, or between about 1% and about 10%, or between about 4% and about 6%. In a specific example, the particles may have a volume fraction within the binder of about 5%. As shown inFIG. 3B, the detectable layer22utilizing the stacks of alternating materials may be configured to reflect certain windows of the electromagnetic spectrum while being substantially transparent to other windows or bands. In specific examples, the detectable layer22utilizing such particles may selectively reflect light having a wavelength of about 905 nm or about 1550 nm (e.g., near-infrared radiation) to enhance reflectivity at wavelengths traditionally utilized by LIDAR systems.

According to another example, the detectable layer22may be configured to fluoresce at a predetermined wavelength in response to receiving an excitation emission. In such an example, the detectable layer22may include a binder and one or more types of organic molecules (e.g., a fluorescent component) with a structure configured to fluoresce when illuminated with specific wavelengths of light. According to various examples, the organic molecules may be based on a cyanine structure such as Cypate (e.g., a cyanine component). It will be understood that other molecules and dyes capable of excitation and emission may be utilized without departing from the teachings provided herein. The excitation emission may have a wavelength in the ultraviolet, visible, near-infrared or infrared wavebands of the electromagnetic spectrum. In specific examples, the excitation emission may be of a wavelength used by LIDAR systems such as about 905 nm and/or about 1550 nm. In response to the excitation emission, the organic molecules may be configured to down convert the excitation emission into a longer wavelength emission. In a specific example, the organic molecules of the detectable layer22may be configured to be excited by an excitation emission from a LIDAR system and configured to emit light which is also perceptible by the LIDAR system (e.g., the organic molecules may fluoresce light in the near-infrared band). It will be understood that the reflective and fluorescent examples of the detectable layer22may be combined without departing from the teaching provided herein.

Use of the present disclosure may offer several advantages. First, enhanced reflectivity of the vehicle10to LIDAR systems may provide safety benefits. For example, the increased reflectivity may enhance the “visibility” of the vehicle10to autonomous vehicles, automated system and other system incorporating LIDAR systems. Further, examples of the vehicle10which have a small visible area, such as a motor cycle, may have improved visibility to autonomous vehicles. Second, as the decorative layer26may be transparent or translucent to infrared and/or near-infrared light, the decorative layer26may be positioned over the detectable layer22. Such examples may be advantageous in allowing an owner of the vehicle10to choose any color for the vehicle10, while still allowing the vehicle10to be visible to LIDAR sensors. Third, the ability to place the detectable layer22across multiple body panels14of the vehicle10may increase the visibility of the vehicle10to LIDAR systems. Fourth, by configuring the detectable layer22as the indicium80, the detectable layer22may do more than just reflect light, but rather convey spatial information about what the LIDAR system is sensing.

It will be understood that although described in connection with vehicular components, the present disclosure may be equally applied to non-automotive components. For example, the detectable layer22and the decorative layer26of the present disclosure may be applied to signs, clothing, bicycles, hats, personal protective equipment, children's toys, pet leashes and harnesses, etc., without departing from the teachings provided herein. While the foregoing disclosure may be advantageous in allowing LIDAR systems to detect vehicles, application of the detectable layer22to the above enumerated items may allow for the detection of common road hazards (e.g., people, pets, bikers) by automated vehicles utilizing LIDAR detection systems.