Light guide glass material

Abstract

The vehicle glazing (10) has a light guide stack (22) disposed between a portion of an inner transparency (26) and a portion of an outer transparency (28). The light guide stack includes a polycarbonate film (32) bonded to the transparencies (26, 28) by PET layers (38, 40). One side of the PET layers (38, 40) is attached to the film by silicone (34, 36) and the other side is attached to the transparencies by PVB (42, 44). The film's extended tab terminates on an edge to which the light bar (14) is attached, and visible light propagates from the light bar through the edge and into the film. Visible light propagates through etched sections in the film's smooth surface to form an image. One transparent extension protects the polycarbonate tab and supports the light bar during installation of the glazing within the vehicle opening.

Description

[Technical field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 62 / 894,037, filed Aug. 30, 2019, which is incorporated herein by reference in its entirety.

[0002] The invention disclosed herein relates to glazing suitable for use in vehicle windows and methods of making such glazing. [Background technology]

[0003] Vehicle developments are moving towards electric vehicles and even autonomous vehicles. In addition, there is a desire for communication from the vehicle to those outside it, such as pedestrians and other vehicle operators. For these and other reasons, there has been growing interest in vehicle glazing that cooperates with various sensors to form communications with the vehicle operator and others through designs and alphanumeric codes displayed on the glazing. Such combinations also support "heads up" displays, which are often considered safer and more reliable than alternative information systems and methods.

[0004] In this regard, attention has been directed to systems incorporating LED front lighting technology. LEDs are well suited for light guide designs intended for high performance because LEDs have a relatively high coupling efficiency. In such systems, preferred materials for directing light into the light guide have a high refractive index and a high reflectivity. Inside the light guide, the light is reflected back and forth repeatedly off multiple surfaces as it travels through the light guide in a direction of net internal reflection to the end of the light guide. In particular, LED front lighting has been found to satisfy lower power requirements than conventional backlighting technologies. In LED front lighting systems, the light guide displays a fixed image in response to illumination from light emitting diodes in the "on" state. Such an image is not visible when the LEDs are in the "off" state.

[0005] A "light guide" is an optically transparent material capable of propagating and distributing visible light. Light guide materials employ the principle of reflection caused by the different refractive indices of two materials. Light guides are used to distribute a light source uniformly over a given area. Examples of applications of such light guides include LCD backlighting, information displays, mood lighting, and design light effects.

[0006] In front lighting, all the power is used to create a light image (as opposed to creating a silhouette of the illuminated panel). For example, FLEx Lighting supplies LED front lighting products that incorporate ultra-thin flexible light guides in the form of films or sheets. The light guide film, thinner than a piece of paper, is illuminated through the edge of the film from a light stick or light bar. Typically, LEDs are too large to simply butt up against the edge of the film. Instead, a light bar is attached to the edge of the thin film, and the LEDs are focused at the end of the light bar to propagate visible light into the film.

[0007] The ultra-thin light guide film can conform to many contours and therefore many glass shapes. The ultra-thin light guide film emits visible light from the film surface according to the etching of the surface. Thus, the film can convey a message according to a series of designs and alphanumeric characters etched into the surface of the light guide film. By way of example, such messages are conventional road signs and / or written instructions.

[0008] A typical thin film light guide has a thickness in the range of about 25 to 75 microns (μm). Light bars are used to deliver light in the visible wavelength range to the edges of the film. Light transmitted into the light guide film is generally confined between the smooth surfaces of the film, except in areas where the smooth surface is disturbed by etching or other surface discontinuities. It has been found that this configuration requires relatively low power and provides relatively high uniformity, good contrast, good color range, and full viewing angle.

[0009] According to the invention disclosed herein, the ultra-thin light guide is a film of polycarbonate (PC) material that functions as a light guide and light transmitting film. Vehicle glass materials typically employ polyvinyl butyral (PVB) as an interlayer. PC does not adhere to PVB, but it adheres to polyvinyl acetate (EVA) and polyurethane (PU), so an EVA or PU layer can be used on both sides of the PC film to adhere the light guide to the adjacent transparency in the light guide stack.

[0010] In addition, polyethylene terephthalate (PET) adheres to PVB and urethane, and silicone can be used as a bonding agent with PC. Thus, the PC layer, or PC film, of the light guide stack may include multiple transparent layers of PET facing both sides of the PC film. A PVB layer is added to one side of the PET layer and adheres to the adjacent transparency. Since the PET is not laminated to the PC, the multiple PET layers are bonded to the PC layer by an adhesive such as silicone. However, it was found that further modifications were necessary to make the light guide stack suitable for use in vehicle glazing. Summary of the Invention

[0011] In accordance with the invention disclosed herein, a glazing material for projecting light in the form of an image includes a glazing material laminate including at least one transparency and a light guide laminate stack including a PC film. The surface of the PC film is etched according to a design or symbol in a form designed to convey a message. When visible light is propagated from a side edge of the PC film, light is emitted from the etched portion of the surface according to the etched design or symbol.

[0012] In some cases, the light source is added to the glass element before it is delivered to the vehicle assembly site, and in other cases, the light source is added when the glass element is installed in the vehicle opening (portal) for the glass element.

[0013] The glazing laminate includes a film that includes a polyethylene terephthalate (PET) clad layer on one or both sides of the PC film, which may be bonded to the PC with a bonding agent such as silicone.

[0014] In vehicle glazing that includes more than one transparent sheet, the transparent sheets are typically separated by an interlayer, such as PVB or other suitable material. To match the thickness of the light guide laminate stack to the thickness of those portions of the glazing that include an interlayer, the light guide laminate stack often includes one or more spacing layers. In preferred embodiments, the spacing layers may be comprised of EVA, PU, ​​PVB, or combinations thereof.

[0015] To aid in the lamination process, a partial vacuum may be applied to the light guide laminate stack to remove air trapped between the layers of the light guide laminate stack. In some cases, the glass material includes a transparent sheet having a peripheral side edge that defines the outer periphery of the transparent sheet and is combined with the light guide laminate stack having a PC film that terminates at a film edge. The film edge is disposed inside the periphery of the transparent sheet, and the transparent sheet is connected to a light source that is connectable to the transparent sheet. In this manner, the transparency extends beyond the PC film to protect against inadvertent bending, bumping, or other impacts on the PC film. This protection is particularly important during installation of the light guide glass material in the vehicle opening. At this point, the glass material assembly is heat treated to bond the laminated layers of the glass material process. The heat treatment process tends to make the polycarbonate tabs brittle and susceptible to damage from impacts with the vehicle body. The glass material with the film edge disposed inside the periphery of the transparent sheet may be degassed with a vacuum bag. In some cases of glazing constructed in this manner, the light source can be added prior to heat treating the light guide glazing, thereby eliminating the need for the assembly to reach the assembly site and couple the light source to the glazing stack during the vehicle assembly process.

[0016] In other cases, the glass material includes a transparent sheet having a peripheral side edge that defines the outer periphery of the transparent sheet, combined with a light guide laminate stack including a PC film that terminates at a film edge located on the outside of the transparent sheet. In this way, the polycarbonate film of the light guide stack extends to form a light guide tab. Before attaching the light source to the PC film, the glass material may be degassed by using a vacuum collar that surrounds the transparent sheet and the light guide stack adjacent its periphery. Glass material configured in this way can be manufactured relatively quickly because degassing using a vacuum collar is faster than degassing using a vacuum bag.

[0017] Preferably, the disclosed glass material includes a first transparent body, a second transparent body, and a light guide laminate stack disposed between a portion of the first transparent body and a portion of the second transparent body. The light guide laminate stack includes a polycarbonate film, the polycarbonate film including a plurality of major surfaces disposed opposite each other. The portions of the plurality of major surfaces disposed opposite each other constitute a smooth continuous surface, while at least one portion of at least one major surface has a plurality of interruptions in the smooth continuous surface of the major surface. Light in the visible light spectrum propagates through the polycarbonate film between the smooth continuous portions of the plurality of major surfaces of the polycarbonate film and exits the polycarbonate film through the interruptions in the smooth continuous surface. An interlayer is disposed between the portions of the first transparent body and the portions of the second transparent body that are not present with the light guide laminate stack. The interlayer has a nominal thickness approximately the same as a nominal thickness of the light guide stack, thereby limiting the creation of bubbles and distortions during the manufacture of the glass material in areas of the glass material where the light guide stack abuts the interlayer. A light bar is coupled to the edge of the polycarbonate film such that light in the visible spectrum propagates from the light bar through the edge of the polycarbonate film and into the polycarbonate film.

[0018] Other objects and advantages of the invention disclosed herein will become apparent to those skilled in the art upon reading the detailed description of certain preferred embodiments herein.

[0019] Preferred embodiments of the present invention disclosed herein are shown and described below in connection with the accompanying drawings. [Brief description of the drawings]

[0020] [Figure 1] FIG. 1 is a perspective view of a light guide glass material according to the invention disclosed herein. [Diagram 2] 2 is a perspective view of the light guide glass material of FIG. 1 showing further details of the light guide including an extended light guide tab available for connection to a light source such as a light bar. [Diagram 3]3 is an enlarged view of a portion of the light guide glass material shown in FIG. 2, showing further details of the glass material of FIG. 2. [Figure 4] 3 is another enlarged view of a portion of the light guide glass shown in FIG. 2 showing further detail of the glass and including an extension of the PC film. [Diagram 5] 1A-1C illustrate alternate embodiments of the disclosed light guide glass material in which a protective glass layer extends from the body of the glass material. [Figure 6] FIG. 13 illustrates another alternate embodiment of the disclosed light guide glass material in which a protective glass layer extends from the body of the glass material and the light guide body contacts the edge of another glass layer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] In the invention disclosed herein, a glazing laminate including at least one transparent sheet is combined with a light guide laminate stack that is useful for vehicle applications. In many vehicles, the sidelights include only a single transparent sheet, while the front glazing, such as the windshield, includes two or more transparencies separated by interlayers. Although the preferred embodiment herein is described in connection with a windshield, the invention disclosed herein is also applicable to glazing that typically employs a single transparent sheet, in accordance with the claims.

[0022] According to a preferred embodiment herein shown in FIG. 1, a vehicle glazing 10 is used as a windshield, and a light guide stack is applied across the windshield daylight opening (DLO). For reasons that will be explained in detail later, the glazing 10 incorporates a light guide stack 12, which includes a PC film. The glazing 10 includes a first transparent sheet 12a and a second transparent sheet 12b disposed on either side of the light guide stack 12. The first transparent sheet 12a has a peripheral side edge 12c that defines a perimeter of the first transparent sheet 12a, and the second transparent sheet 12b has a peripheral side edge 12d that defines a perimeter of the second transparent sheet 12b. The light guide stack 12 also includes a tab 13, and the PC film 12e of the light guide stack 12 extends outside the perimeter of the first transparent sheet 12a and outside the perimeter of the second transparent sheet 12b. Throughout the light guide stack 12, the PC film 12e has a surface 13a facing the first transparent sheet 12a and a surface 13b facing the second transparent sheet 12b. The surface 13a is disposed on the PC film 12e opposite its surface 13b, and a film edge 13c is disposed between the surfaces 13a and 13b. The portions of the film surface 13a and the surface 13b each have a smooth continuous surface. Light in the visible light spectrum illuminating the film edge 13c propagates through the PC film 12e between the smooth continuous portion of the film surface 13a and the smooth continuous portion of the film surface 13b.

[0023] When the glazing 10 is installed in a vehicle, a light source, such as a light bar 14, may illuminate the film edge 13c and transmit light through the PC film 12e. In some cases, a light source, such as a light guide 14, is adhered to a portion of the film edge 13c of the PC tab 13. In other cases, a light source, such as a light guide 14, is adhered to a portion of the film edge 13c, and the film edge 13c may be disposed about a perimeter defined by the peripheral side edge 12c of the first transparent sheet 12a, about a perimeter defined by the peripheral side edge 12c of the second transparent sheet 12b, or about a perimeter of both the first transparent sheet 12a and the second transparent sheet 12b.

[0024] When the end 16 of the light bar 14 is illuminated with visible light, for example from an LED 16a, the light from the LED propagates through the light bar 14 and the adjacent film edge 13c of the PC film 12e. Inside the PC film 12e, the light propagates between the smooth surface 13a and the smooth surface 13b of the PC film 12e. The portions of the surfaces 13a, 13b of the PC film 12c may have a pattern of indentations so that the surfaces are discontinuous. Such a pattern may be created by etching or a similar process to form a pattern in the shape of alphanumeric characters, designs, or other images. Light traveling through the PC film 12e between the surfaces 13a, 13b passes through the indentations or discontinuities created by the etching and exits the PC film 12e, forming a visible pattern on the surface 13a or surface 13b that follows the pattern of discontinuities. Thus, surface 13a or surface 13b may be engraved or etched with a series of designs or alphanumeric characters, thereby forming a readable message or instructional image. In the example of Figure 1, the design shows a visible message warning of a curve in the road.

[0025] Further details of the inventive vehicle glazing disclosed herein are shown in Figure 2. Figure 2 shows a light guide stack 22 that extends only a portion of the daylight opening (DLO) of the vehicle glazing 24. Details of the multiple glazing transparencies, the interlayers separating the multiple glazing transparencies, and the light guide stack 22 are shown and described in connection with Figures 3 and 4.

[0026] 3 shows the light guide stack 22 and the remaining glass laminate 24. In the glass laminate 24, an inner transparency 26 and an outer transparency 28 are separated by a PVB interlayer 30. During the lamination process, the transparent layers 26, 28 are bonded to the PVB interlayer 30 such that, if either the transparency 26 or the transparency 28 fractures, the transparent layers 26, 28 are sufficiently bonded to the PVB interlayer 30 that the pieces of the transparent layers 26, 28 remain generally attached to the PVB interlayer 30.

[0027] In order to limit weight, reduce material costs, and for other factors, the overall thickness of the glazing 24 is made as thin as possible. However, it has been found that the practical effects of glazing performance requirements, such as confrontation with wind loads, impact resistance, chip resistance, shatter resistance, and other factors, impose a minimum thickness for vehicle glazing. Although the minimum thickness for vehicle glazing varies depending on the purpose and orientation of the glazing in the vehicle, commercial factors have collectively established minimum thicknesses for the conventional clear layer and the conventional lamination layer. For PVB used in windshields, the nominal thickness of the conventional PVB layer is 0.76 mm. In some cases, a thinner PVB layer, as thin as 0.38 mm, may be used for vehicle windshields.

[0028] The light guide stack 22 is connected to the end of the PVB interlayer 30. Connecting at the Border It has been found that for glazing such as that shown in Figures 2 and 3, the overall thickness of the light guide stack must be very close to the overall thickness of the PVB interlayer 30 to avoid visible distortion, air bubbles, and other undesirable effects that may occur during the lamination process. Thus, in a motor vehicle glazing intended for use as a windshield, where the PVB interlayer has a nominal thickness of the standard 0.76 mm, the thickness of the light guide stack must also be approximately 0.76 mm to avoid visible distortion of the glazing after lamination.

[0029] In the example embodiment of FIG. 3, the light guide stack 22 includes a PC film 32 and PET cladding layers 38, 40 bonded to both sides of the PC film 32 by silicone layers 34, 36, respectively. In other examples, cladding layers other than PET bonded by silicone may be used. The thicknesses of the PC film 32, cladding layers 38, 40, and silicone layers 34, 36 are significantly thinner than the thickness of the PVB interlayer 30, which is 30 mils. For example, the PC film thickness is about 5 mils, each of the PET cladding layers is about 3 mils, and each of the silicone layers is about 1.6 mils. Two spacing layers 42, 44 are included to approximate the thickness of the light guide laminate stack to that of the PVB interlayer 30. The spacing layers 42, 44 can each bond the PET layers 38, 40 to the respective transparencies 26, 28. In the example of FIG. 3, the spacing layers 42, 44 are made of PVB. Other compositions such as EVA, PU, ​​etc. may be used for the spacing layers 42, 44. In some cases, the light guide stack is constructed from a layer of PC film 32 and a layer of EVA or PU bonded to the PC film 32 and transparencies 38, 40, avoiding the need for PET, PVB, or other layers. PVB, PU, ​​and EVA are commercially available in thicknesses of approximately 15 mils. By selecting spacing layers 42, 44 with a nominal thickness of 15 mils, the total thickness of the light guide laminate stack is close enough to the total thickness of the PVB interlayer 30 to avoid different thicknesses causing visible distortion, bubbles, and other undesirable effects during the lamination process.

[0030] According to the invention disclosed herein, the light guide stack 22 constitutes an intermediate layer between the inner transparency 26 and the outer transparency 28. In the invention disclosed herein, the transparencies 26, 28 can be glass. Since PET does not bond to glass, the PET layers of the light guide stack 22 are covered with PVB layers 42, 44, respectively. The total thickness of the light guide stack 22 includes both PVB layers 42, 44 covering the PET layers 38, 40. The light guide stack 22 should be approximately equal to the nominal thickness of the PVB intermediate layer 30. In the example of FIG. 3, the thickness of the PC film 32, silicone layers 34, 36, PET layers 38, 40, and PVB layers 42, 44 should be approximately equal to the thickness of the PVB intermediate layer 30, which is 0.76 mm.

[0031] Although obtaining an overall thickness of the lightguide stack 22 consistent with the thickness of the PVB interlayer 30, repeated experimentation to achieve the required overall thickness has shown that the selection of each thickness of the PC film 32, the silicone layers 34, 36, the PET layers 38, 40, and the PVB layers 42, 44 is not a matter of simply selecting or modifying commercially available products. Other factors and limitations that give rise to variables not apparent to those skilled in the art must also be accommodated. In fact, the identification and selection of preferred thicknesses for each layer of the lightguide stack 22 is done in a manner that is quite counterintuitive and contrary to previously known choices and methods.

[0032] For example, the PVB layers 42, 44 must have a minimum thickness to support sufficient lamination with the respective glass layers 26, 28. This is necessary to allow the glass material 24 incorporating the light guide stack 22 to meet various windshield performance requirements that affect, such as avoidance of free glass shards in case of fracture, and other factors. It has also been found that the PET layers 38, 40 of the light guide stack 22 must have a thickness of at least 0.0762 mm (3 mils). This is necessary to avoid undesirable consequences for the PET layers during lamination, namely, flow, wrinkling, and uneven surfaces of the PET layers 42, 44 during the autoclave step of the lamination process. The use of multiple PET layers, with typical multiple PET layers (typically about 0.0508 mm) being typical, was surprising and unpredictable, since the prior art determined that multiple PET layers having such effects should be made thinner than 3 mils (about 0.076 mm) and not as thick as the invention disclosed herein. As another example, it has been found that to avoid wrinkling of the PC film during the autoclave step of the lamination process, the PC film thickness must be 2 mils (0.0508 mm). Preferably, the thickness of the PC film is around 5 mils (0.127 mm), and more preferably in the range of 3-4 mils (0.0508 mm).

[0033] FIG. 4 shows that, in accordance with the invention disclosed herein, it has been found preferable to remove the PET layers 38, 40 and the silicone layers 43, 36 from the portion of the PC film 32 that extends as a tab 13 beyond the perimeter of the transparency 26, 28. In addition, it has been found preferable to make the PC film 32 thinner than a typical thin light guide. Preferably, the thickness of the PC film 32 is in the range of 2 mils to 5 mils. The reason for removing the PET and silicone layers from the extended tab portion of the PC layer 32 and limiting the thickness of the PC film 32 is for improved manufacturing methods. These modifications and limitations of the PC film provide improved flexibility to accommodate commercial processes for forming vehicle glazing.

[0034] In the commercial manufacture of vehicle glazing, the glazing stack is subjected to a vacuum process prior to the autoclave step of the lamination process. The purpose of the vacuum process is to remove air trapped between the various layers of the glazing prior to the autoclave step of the lamination process. If excess air remains between these layers, the glazing will tend to have visible defects such as air bubbles. Other undesirable results such as delamination may also occur.

[0035] To remove excess air, a vacuum ring is placed around the periphery of the glass material 24 prior to the lamination process. The vacuum ring tightly abuts the edge of the glass material 24 so that the vacuum inside the vacuum ring is transferred to the interior of the glass material. In this way, air is drawn between the layers of glass material and into the vacuum ring until a sufficient vacuum level is reached inside the glass stack.

[0036] In order for the vacuum ring to effectively transfer the vacuum to the interior of the glass stack, the ports of the vacuum ring must be close to the edge of the glass stack. This means that there must be a small gap tolerance between the periphery of the glass stack and the inward-facing side of the vacuum ring. As previously explained in connection with FIG. 1, the tab portion 13 of the PC film 12e extends beyond the periphery 12c, 12d of the transparent sheets 12a, 12b of the glass material, so that the light bar 14 transfers light into the PC film 12e through the exposed edge 13a of the PC film 12e. However, because the tab 13 of the PC layer 12 extends beyond the periphery of the transparent sheets 12a, 12b, the vacuum ring will interfere with the tab 13 when positioned around the periphery of the glass stack.

[0037] Previously, it was thought that the PC film 12e must have sufficient mechanical strength to tolerate contact with the vacuum ring. This led to designs in which the PET cladding layers 38, 40 of the PC film 32 were maintained throughout the tab 32 and further the PC film 32 was made thicker to give the PC film 32 added mechanical strength to tolerate contact with the vacuum ring. However, surprisingly, the invention disclosed herein produced the opposite result.

[0038] First, according to the invention disclosed herein, the PET layers 38, 40 and the silicone layers 34, 36 are completely removed from the PC film 32. Second, the PC film 32 is thinner than a previously known thickness. In the invention disclosed herein, the PC film 32 solves the interference with the vacuum ring by its flexibility, not its mechanical strength. In the invention disclosed herein, the PC film 32 is flexible enough to bend out of the path of the vacuum ring without damaging the PC film, while the vacuum ring still pulls a sufficient vacuum inside the glass material. This goes against the requirement of additional mechanical strength created by a relatively thick PC film.

[0039] 2-4 may further incorporate a light source, such as a light guide affixed to a tab portion of the PC film 32. The light source may be added prior to delivery of the glass material to the vehicle assembly site or may be added to the glass material as part of the larger process in vehicle assembly.

[0040] FIG. 5 shows an alternative embodiment of the invention disclosed herein. In the embodiment of FIG. 5, the PC film 12e includes a PC film tab 13 that terminates at an edge 13a. The light bar 14 is coupled to the edge 13a of the PC film 12e as described in connection with FIG. 1. Also as described in connection with FIG. 1, when the end 16 of the light bar 14 is illuminated, light propagates from the light bar 14 through the edge 13a into the PC film 12. However, in the embodiment of FIG. 5, a glass sheet 28 extends beyond the edge 13a of the tab 13 and beyond at least a portion of the light bar 14. As such, the light bar 14 may be secured to the glass sheet 28 by a bonding agent or other suitable fastening method, which provides mechanical support for the light guide 14 and provides greater stability for the light guide 14 and the PC film tab 13 outside the perimeter of the peripheral side of the transparency 26.

[0041] 5 provides greater durability during manufacturing and handling of the glass material 10, as well as when the glass material 10 is installed in a vehicle. It has been found that this structure tends to protect the PC film 12 from breaking or tearing during handling or in the light guide installation process after autoclaving. The extensions of the glass sheet 28 can also serve as guides when positioning the glass material 10 during installation in a vehicle, and to maintain stability of the tabs 13 and light guide 14 when the glass material is installed.

[0042] In the embodiment of Figure 5, the vacuum channels are generally not suitable for degassing the laminated stack of glass materials because the gap tolerances of the vacuum channels do not accommodate the difference between the perimeter of transparency 26 and the perimeter of transparency 28. For example, a vacuum channel that travels close to the edge of transparency 26 will interfere with the extended portion of transparency 28. Therefore, in the embodiment of Figure 5, a vacuum bag or equivalent device may be used to degas the glass materials prior to heating in an autoclave or other curing process.

[0043] It has been found that the extended portions of the glass sheet 28 provide protection for the PVB, polyurethane, or other interlayer materials, especially after such materials have been rendered somewhat brittle by autoclaving or other heating or curing processes. For example, when installing the glass material in an opening in a vehicle, the extended tabs can be damaged by contact with the vehicle body.

[0044] 6 shows the light bar 14 in contact with the peripheral side edge 12c of the transparency 26. When the light bar 14 is positioned in this manner to contact the peripheral side edge prior to autoclaving, the body of the light guide 14 forms a seal with the peripheral side edge 6 of the transparency 26 during the autoclave step of the lamination process. This seal helps maintain the lamination of the light guide stack and avoid air bubbles in the lamination, especially near the peripheral border of the transparency 26. To aid in the formation of such a seal, the invention disclosed herein employs light guides having bodies made of Delrin® or a similar plastic material.

[0045] The embodiment of FIG. 6 also illustrates that the thickness of the light guide (measured in a direction perpendicular to the surface of the inner transparent body 28) is preferably less than 3.0 mm. More specifically, the thickness (T) of the light guide 14 is 2.6 mm or less. The thickness of the light guide as used in connection with the embodiment of FIGS. 1-4 is typically 5 mm. However, the low profile (thickness) of the light guide preferred for the embodiment of FIG. 6 allows the light bar to abut the periphery of the inner transparent body 26, and the maximum height of the assembled glazing (including the light bar) is not greater than the outer surface of the outer transparent body 26. In this manner, the assembled glazing can accommodate standard size and shape openings that accommodate the glazing of many vehicles.

[0046] Other features, objects, and advantages of the inventions disclosed herein are set forth below in conjunction with the claims.

Claims

1. A glazing that projects a predetermined pattern of light in response to an illumination signal, comprising: A glass material stack; a light guide laminate stack; The glass laminate comprises: a) at least one transparent sheet defining a peripheral side edge; b) a second transparent sheet having a surface facing the at least one transparent sheet; and c) an intermediate layer disposed between the second transparent sheet and the at least one transparent sheet, the intermediate layer having a first surface facing a surface of the at least one transparent sheet and a second surface facing a surface of the second transparent sheet directed toward the at least one transparent sheet, the separation length between the first surface and the second surface of the intermediate layer defining a thickness of the intermediate layer; the light guide laminate stack is disposed between the at least one transparent sheet and the second transparent sheet in a portion of the glass laminate and borders an edge of the interlayer, the light guide laminate stack having a first surface facing at least a portion of the at least one transparent sheet and including a film; the film has a first film surface, a second film surface disposed on the film opposite the first film surface, and a film edge between the first film surface and the second film surface, each of a portion of the first film surface and a portion of the second film surface comprising a smooth continuous surface whereby light in the visible spectrum propagates through the film between a portion of the smooth continuous surface of the first film surface and a portion of the smooth continuous surface of the second film surface, the first film surface comprising a textured pattern within its smooth continuous surface whereby light propagating through the film between the first film surface and the second film surface passes out of the first film surface from the textured pattern of the first film surface; further comprising a light source coupled to a film edge of a film of the light guide laminate stack, whereby light in the visible spectrum propagates from the light source through the film edge and into the film between the first film surface and the second film surface; The light source has a body contacting a periphery of the second transparent sheet.

2. The glass material of claim 1 , wherein the light source comprises a light emitting diode.

3. The glass material of claim 1 , wherein the films of the light guide laminate stack comprise polycarbonate.

4. 4. The glass material of claim 3, wherein the light guide laminate stack further comprises at least one polyethylene terephthalate layer between the film and the at least one transparent sheet.

5. 4. The glass material of claim 3, wherein the light guide laminate stack further comprises at least one spacing layer between the film and the at least one transparent sheet, the spacing layer material being selected from the group consisting of polyvinyl butyral, ethylene vinyl acetate, polyurethane, and combinations thereof.

6. 5. The glass material of claim 4, wherein the light guide laminate stack further comprises at least one spacing layer between the polyethylene terephthalate layer and the at least one transparent sheet, the spacing layer material being selected from the group consisting of ethylene vinyl acetate, polyvinyl butyral, polyurethane, and combinations thereof.

7. The glazing of claim 1 , wherein the film edge is disposed outside a perimeter defined by a peripheral side edge of the at least one transparent sheet.

8. The glass material of claim 1 , wherein the light guide laminate stack has a thickness that corresponds to a thickness of the interlayer.

9. The glass material of claim 1 , wherein the films of the light guide laminate stack comprise polycarbonate.

10. 10. The glass material of claim 9, wherein the light guide laminate stack further comprises at least one polyethylene terephthalate layer between the film and the second transparent sheet.

11. 11. The glass material of claim 10, wherein the light guide laminate stack further comprises a spacing layer between the polyethylene terephthalate layer and the second transparent sheet, the spacing layer material being selected from the group consisting of polyvinyl butyral, polyurethane, ethylene vinyl acetate, and combinations thereof.

12. 10. The glass material of claim 9, wherein the light guide laminate stack further comprises a spacing layer between the film and the second transparent sheet, the spacing layer material being selected from the group consisting of ethylene vinyl acetate, polyurethane, and combinations thereof.

13. 12. The glass material of claim 11, wherein a film edge of the film extends beyond a perimeter of the second transparent sheet to form an extension tab outside a perimeter of the second transparent sheet and comprising a distal end of the extension tab.

14. 14. The glass material of claim 13, wherein the film has a thickness in the range of 2 mils to 5 mils.

15. The glazing of claim 1 , wherein the body of the light source forms a seal with a peripheral edge of the second transparent sheet.

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