Display backlighting to avoid windshield reflections

Abstract

A system for backlighting a display to avoid creating reflections, the system may include a light source configured to generate light, a collimating light guide configured to collimate the light into a collimated light, and a redirecting element configured to direct the collimated light into a vertically narrow light that is operable to avoid creating reflections.

Description

[Technical Field]

[0001] [CROSS-REFERENCE TO RELATED APPLICATIONS] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 482,452, filed January 31, 2023, which is incorporated herein by reference in its entirety.

[0002] [Technical field] The present disclosure relates to backlights and backlight systems configured to backlight displays, such as, but not necessarily limited to, systems that backlight displays to avoid causing reflections on a vehicle windshield.

[0003] A visual display may be electronically configured to present images, text, video, and / or media to one or more viewers in response to electrical signals provided by an electronic device configured to interact with the viewers or to receive data, information, and other material desired for presentation. A wide variety of electronic devices may include such displays, which may typically be configured in various shapes and sizes and with various brightness profiles depending on the intended environment of use. In a vehicle, such as an automobile, but not necessarily limited to an automobile, one or more displays may be configured to exchange media with the vehicle operator and / or one or more passengers. Some vehicles may include a windshield, windscreen, window, or other surface or structure near the display. A display may be included within the dashboard, instrument panel, infotainment system, control panel, fascia, or other portion of the vehicle below the windshield or adjacent to another vehicle surface.

[0004] It may be undesirable for light emitted from a display to reflect off the windshield or other vehicle surfaces. To address such reflections, some vehicles in the past have included blocking elements, shutters, obstructions, louvers, or other physical infrastructure near or as part of the display to prevent light emitted therefrom from reflecting off the windshield or other surfaces. Blocking features may be disadvantageous due to their cost and / or because the blocked, louvered, etc. light is wasted or unusable. This may lead to the display having to be driven with more power, i.e., less efficiently. Summary of the Invention

[0005] One aspect of the present disclosure relates to a system for backlighting a display to avoid causing reflections on a vehicle windshield. The system may include a backlight configured to provide a vertically narrow light operative at the display to interface media with one or more viewers in a manner that avoids causing reflections on the windshield or other surfaces of the vehicle. The backlight may include a plurality of prisms configured to emit the vertically narrow light at the display in a manner that minimizes wasted and / or unusable light and in a manner that minimizes power consumption and maximizes power efficiency.

[0006] One aspect of the present disclosure relates to a backlighting system for preventing a display from causing windshield reflection inside a vehicle when the windshield reflection occurs due to the display emitting an optical signal at a vertical angle greater than the reflection angle. The backlighting system may include an edge light source configured to generate an edge light, a collimating light guide configured to collimate the edge light into a collimated light, and a redirecting element statically configured to direct the collimated light into a narrow vertical light having a vertical cutoff angle less than the reflection angle, the narrow vertical light being operable with the display to generate an optical signal without a windshield reflection.

[0007] The redirecting element may include a plurality of prisms configured to direct the collimated light into a vertically narrow beam.

[0008] The prism may be triangular in shape and may include a light receiving surface configured to receive collimated light, a reflecting surface configured to reflect the collimated light received from the light receiving surface, and an output surface configured to emit a vertically narrow beam of light toward the display.

[0009] The redirecting element may be constructed from a light-transmitting material.

[0010] The prism may be fixedly attached to the base of the redirecting element or may be included as part thereof.

[0011] The receiving surface may be configured to refract the collimated light before it reaches the reflecting surface.

[0012] The light receiving surface may be angled at an acceptance angle determined relative to the display normal, and the reflecting surface may be angled at a reflection angle. The light receiving surface may cooperate with the reflecting surface to restrict normal narrow light to an output angle that is smaller than the reflection angle.

[0013] The collimating light guide can be configured to emit collimated light at a collimation angle substantially across the entire output face of the collimating light guide. The output face of the collimating light guide can be parallel to the display and perpendicular to the normal. The surface area of ​​the output face can be larger than the surface area of ​​the input to the collimating light guide that receives edge light.

[0014] A diffuser may be disposed between the redirecting element and the display, and optionally the diffuser may be configured to spread the narrow vertical light into a diffuse light to improve uniformity.

[0015] The vertically narrow light may be operable with the display to emit a light signal having a vertical luminance profile that is smaller than the horizontal luminance profile.

[0016] The redirecting element may be constructed from a light-transmitting material having a textured or shaped surface configured to direct the collimated light towards the display in a fixed manner without physically blocking the collimated light from passing through.

[0017] One aspect of the present disclosure relates to a backlight system for a display, which may include an edge light source configured to generate edge light, a collimating light guide configured to collimate the edge light into collimated light, and a plurality of triangular shaped prisms statically configured to direct the collimated light into a narrow vertical light, the prisms configured to emit the narrow vertical light at a vertical cutoff angle defined relative to a normal to the display.

[0018] The prism may include a light receiving surface configured to receive collimated light, a reflecting surface configured to reflect the collimated light received from the light receiving surface, and an output surface configured to emit a vertically narrow beam of light toward the display.

[0019] The redirecting element may be constructed from a light-transmitting material configured to direct the collimated light towards the display in a fixed manner without physically blocking the collimated light from passing through.

[0020] One aspect of the present disclosure relates to a vehicle. The vehicle may include a windshield and a display disposed behind and below at least a portion of the windshield, where the display may cause windshield reflection when emitting an optical signal at a vertical angle greater than the reflection angle. The vehicle may include a backlight system configured to prevent the display from causing the windshield reflection. The backlight system may include a collimating light guide configured to collimate input light into a collimated light, and an optically transmissive redirecting element configured to statically direct the collimated light into a vertically narrow light having a vertical cutoff angle less than the reflection angle. The vertically narrow light is operable with the display to generate an optical signal without windshield reflection.

[0021] The redirecting element may include a textured or shaped surface configured to statically direct the collimated light towards the display in a fixed manner without physically blocking the collimated light from passing through.

[0022] The redirecting element may include a plurality of prisms configured to statically direct the collimated light towards the display in a fixed manner without physically blocking the collimated light from passing through.

[0023] The foregoing and other features and advantages of the present teachings will be readily apparent from the following detailed description of modes for carrying out the present teachings when taken in conjunction with the accompanying drawings. Even though the following figures and embodiments may be described separately, it should be understood that single features thereof may be combined into additional embodiments.

[0024] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the disclosure. [Brief explanation of the drawings]

[0025] [Figure 1] 1 shows a partial perspective view of a vehicle having multiple display backlights according to one non-limiting embodiment of the present disclosure.

[0026] [Figure 2] 1 shows a schematic diagram of a display according to one non-limiting embodiment of the present disclosure.

[0027] [Figure 3] 1 shows a schematic diagram of a direction-changing element according to one non-limiting embodiment of the present disclosure.

[0028] [Figure 4] 1 shows a schematic diagram of a vertical luminance profile for a display according to one non-limiting embodiment of the present disclosure.

[0029] [Figure 5] 1 shows a schematic diagram of a horizontal luminance profile for a display according to one non-limiting embodiment of the present disclosure.

[0030] [Figure 6] 1 shows a schematic diagram of an exemplary orientation of a display relative to a windshield, according to one non-limiting embodiment of the present disclosure.

[0031] [Figure 7] 1 shows a schematic diagram of another display according to one non-limiting embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0032] Where necessary, detailed embodiments of the present disclosure are disclosed herein, but it will be understood that the disclosed embodiments are merely examples of the disclosure, which may be embodied in various alternative forms. The drawings are not necessarily to scale, and some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not limiting, but should merely be construed as a representative basis for teaching those skilled in the art how to variously employ the present disclosure.

[0033] FIG. 1 shows a partial perspective view of a vehicle 10 having backlighting for multiple displays 12 according to one non-limiting embodiment of the present disclosure. The vehicle 10 is shown, for non-limiting purposes, as an automobile having displays 12 disposed within a dashboard 14 to illustrate an advantageous feature of the present disclosure for backlighting (rear-illuminating) the displays 12 in a manner that avoids or minimizes the creation of reflections on the windshield 18, which may be referred to as windshield reflections. The present disclosure is described primarily, for non-limiting purposes, with respect to avoiding reflections on the windshield 18, as such reflections are typically undesirable to the driver, other vehicle occupants, and / or other vehicles. Those skilled in the art will readily recognize that the backlighting functionality of the present disclosure is useful for illuminating the displays 12 in a wide variety of applications, including backlighting the displays 12 to avoid reflections on windscreens, windows, or other surfaces or structures of the vehicle (not shown).

[0034] This disclosure is described, for non-limiting purposes, with respect to avoiding windshield reflections, highlighting one use of contemplated backlighting that may be particularly beneficial in a vehicle having one or more displays 12 near the windshield 18, such as behind and below a portion of the windshield 18 in the illustrated embodiment. The vehicle 10 may optionally include multiple displays 12 arranged in a pillar-to-pillar or edge-to-edge configuration relative to the windshield 18, and the displays 12 may extend side to side across the dashboard 14. The displays 12 may be configured to display images and other media related to an instrument panel, infotainment system, control panel, or other aspects of the vehicle 10. While the vehicle 10 is described, for non-limiting purposes, as being an automobile, this disclosure fully contemplates utilizing backlighting for other types of displays 12 and display arrangements, including those found on trucks, motorcycles, boats, trains, and / or aircraft, and / or those found as part of stationary objects such as, but not limited to, signs, kiosks, and / or marquees.

[0035] FIG. 2 shows a schematic diagram of a display 12 according to one non-limiting embodiment of the present disclosure. The display 12 may include a transmissive display screen or display element 24 electrically connected to a controller circuit 22 and positioned relative to a backlight 26. Light signals 27 may be presented from a surface 28 of the display 12 to convey visible images, data, information, words, numbers, pictures, graphic shapes, video, information, and other media, such as video (e.g., rearview camera video, frontview camera video, onboard DVD player, etc.). Display signals (e.g., D) may be generated by the controller circuit 22 and received by the light-transmissive display element 24, which may be used, for example, to provide the presentation of gauges (e.g., speedometer, tachometer, fuel, temperature, etc.). The display signals D may convey information used by the light-transmissive display element 24 to modulate the light signals 27. The controller circuit 22 may be configured to generate a brightness signal (e.g., B) to control the backlight 26. The controller circuit 22 may be configured to implement electronic controls for generating display information in the display signal D. The controller circuit 22 may generate and present the brightness, luminance, and other information contained in the luminance signal B.

[0036] The controller circuitry 22 may include one or more microcontrollers. Each microcontroller may optionally include one or more processors, each of which may be embodied as a separate processor, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or a dedicated electronic control unit. A microcontroller may be a type of electronic processor (which may be implemented in hardware, software running on hardware, or a combination of both), which may also include tangible, non-transitory memory (e.g., read-only memory in the form of optical, magnetic, and / or flash memory). A microcontroller may include an amount of random-access memory, read-only memory, flash memory, and other types of electrically erasable, programmable read-only memory appropriate to the application, as well as accompanying hardware (high-speed clocks or timers, analog-to-digital and digital-to-analog circuits, input / output circuits and devices), and appropriate signal processing and buffering circuitry. Computer-readable and executable instructions embodying the present disclosure may be stored in memory and executed as described herein. The executable instructions may be a series of non-transitory instructions used to run an application on the microcontroller (either in the foreground or background). The microcontroller may receive commands and information, such as in the form of one or more input signals, from various controls or components and control the light-transmissive element 24 in response to one or more control signals that are forwarded to the display 12.

[0037] The light-transmissive display element 24 can be configured to implement a display panel that modulates a vertically narrow light 25 emitted from a backlight 26 as the vertically narrow light 25 passes from one side of the light-transmissive display element 24 to the other. The light-transmissive display element 24 can be a color light-transmissive display element 24 or a black-and-white light-transmissive display element 24. The light-transmissive display element 24 can be mounted adjacent to (or next to) the backlight 26. The light-transmissive display element 24 operates to change opacity, color, brightness, etc., in different regions and overall in response to a display signal D, which can optionally generally modulate the intensity and color to produce a light signal 27. The modulated light 24=5 can form an image in the light signal 27. In various embodiments, the light-transmissive display element 24 can be implemented as a thin-film transistor (TFT) liquid crystal display (LCD) or a passive liquid crystal display. Other light transmissive display element 24 technologies can be implemented to meet the design criteria of a particular application.

[0038] The backlight 26 may include edge light sources 32 configured to generate edge light 38. The edge light sources 32 may be located at the edges of the display 12, such as along a top edge 34 or a bottom edge 36 (see FIG. 1 ). While the backlight 26 is primarily described with reference to including edge light sources 32, advantages associated with edge-backlit displays 12 tend to be lower cost and / or better performance, at least compared to more expensive full-array local dimming (FALD) backlight 26 configurations, particularly when used in larger displays 12, such as edge-to-edge or pillar-to-pillar display types, instrument panel displays, etc. This is provided for non-limiting purposes, as the present disclosure also fully contemplates light sources for the backlight 26 originating from arrays or other non-edge-type light sources. The backlight 26 may include a collimating light guide 40 configured to collimate the edge light 38 into collimated light 42. Collimating light guide 40 may be configured to receive edge light 38 at input 46 and transmit corresponding collimated light 42 at output 48, where, optionally, collimated light 42 is evenly or consistently collimated across substantially the entire surface of output 48. The surface area of ​​output 48 may be larger than the surface area of ​​input 46. Collimating light guide 40 may be constructed from an optically transparent material or otherwise configured to collimate edge light 38 in a contemplated manner.

[0039] The backlight 26 may optionally include a reflector film 50 disposed below the collimating light guide 40. The reflector film 50 may be configured to recycle the edge light 38, the collimated light 42, and any reflected light, such as by redirecting the corresponding light back into the collimating light guide 40. The collimated light 42 output from the collimating light guide 40 may be emitted toward a redirecting element 54 configured to direct the collimated light 42 into a vertically narrow beam 25, i.e., light contemplated herein to facilitate illuminating the light-transmissive display element 24 in a manner that avoids the occurrence of reflections within the windshield 18. Figure 3 shows a schematic diagram of a redirecting element 54 including a plurality of prisms 58 configured to provide a shaped or textured surface operable to direct the collimated light 42 into a vertically narrow beam 25. Redirection element 54 may be composed of or may include prisms 58, which may be triangular prisms 58 arranged in a fixed configuration to statically direct collimated light 42 into vertically narrow light 25. The orientation and relationship of prisms 58 may be design parameters that cannot be changed once redirection element 54 is applied to base 59, which may be a layer or other support structure.

[0040] The redirecting element 54 may be composed of a light-transmitting material, such as a film or other structure, having prisms 58 coated, polished, glued, or otherwise shaped thereon. The triangular prism 58 is presented for non-limiting purposes, as the present disclosure fully contemplates other geometries suitable for similarly directing the collimated light 42 into the vertically narrow light 25. The geometry of the prism 58 may be defined by a light-receiving surface 62, a reflecting surface 64, and an output surface 66. The light-receiving surface 62 may be configured to refract or otherwise transmit the collimated light 42, the light-receiving surface 64 may be configured to reflect the collimated light 42 into the vertically narrow light 25, and the output surface 66 may be configured to emit the vertically narrow light 25 toward the light-transmitting display element 24. The light-receiving surface 64 may be configured to provide an angle of incidence of the collimated light 42 sufficient to limit the vertically narrow light 25. The acceptance angle (φ1) of the acceptance surface 62 and the reflection angle (φ2) of the reflection surface 64 can be defined relative to a normal 68 of the display 12, and the acceptance angle φ1 and the reflection angle φ2 are shown as equal for non-limiting purposes.

[0041] Collimating light guide 40 may be configured to direct collimated light 42 toward prism 58 at a collimation angle (θ), which may optionally be consistent or uniform across the surface area of ​​collimating light guide output 48. The collimation angle θ may be defined relative to normal 68, such that the collimation angle θ in the exemplary embodiment may be greater than the output angle (θ) defined relative to normal 68 of vertically narrowed light 25 output toward light-transmissive display element 24. The output angle θ of vertically narrowed light 25 is shown, for illustrative purposes, as effectively zero or parallel to normal 68 of display 12. However, vertically narrowed light 25 may effectively be emitted from prism 58 non-parallel to normal 68, i.e., at an angle θ greater than zero. Referring to FIG. 1, a normal 68 may be defined as a line or vector perpendicular to the surface 28 of the display 12, a horizontal axis 70 may be defined across the left and right sides of the display 12, and a vertical axis 72 may be defined across the top and bottom of the display 12.

[0042] FIG. 4 shows a schematic diagram of a vertical luminance profile 74 for display 12 according to one non-limiting embodiment of the present disclosure. FIG. 5 shows a schematic diagram of a horizontal luminance profile 76 for display 12 according to one non-limiting embodiment of the present disclosure. Vertical luminance profile 74 may be narrower than horizontal luminance profile 76, optionally with vertical luminance profile 74 having a vertical cutoff angle 78 of + / - 30 degrees and horizontal luminance profile 76 having a horizontal cutoff angle 80 approaching + / - 90 degrees. Under certain circumstances, it may be advantageous to make horizontal cutoff angle 80 as large as possible to facilitate widening the output of display 12, while in other circumstances, it may be advantageous to narrow horizontal cutoff angle 80. The horizontal cutoff angle 80 may be less relevant to generating reflections from windshield 18 than the vertical cutoff angle 78, and therefore this disclosure primarily describes redirecting elements 54 configured to manage the vertical cutoff angle 78 to avoid generating reflections on windshield 18.

[0043] The + / - 30 degree cutoff angle 78 is presented for non-limiting purposes, as the present disclosure fully contemplates that the prism 58 be configured to facilitate other cutoff angles 78 and / or to provide a selectable cutoff angle 78. The cutoff angle 78 may be predicted or prescribed according to the spatial relationship between the display 12 and the windshield 18, or between the display 12 and another object from which reflections may be avoided, and thus the cutoff angle 78 may need to be more or less dependent on the orientation of the display 12 relative to the windshield 18. The prism 58 may be correspondingly shaped and configured to facilitate other cutoff angles 78. FIG. 6 shows a schematic diagram of an exemplary orientation of the display 12 relative to the windshield 18 in accordance with one non-limiting embodiment of the present disclosure. The vertically narrow light 25 emitted from different positions on the display 12 may be generated according to the output angle θ2 to ensure that the vertically narrow light 25 emits within the safe-view cone θ3.

[0044] The safe view cone θ3 can correspond to a vertical luminance profile 74 that is substantially unable to reflect off the windshield 18, which in the illustrated configuration is shown to correspond to + / −30 degrees. The vertical cutoff angle 78 of the vertically narrow ray 25 can be configured to be less than the reflection angle θ4. The reflection angle θ4 can correspond to the angle subtended relative to a normal at which a windshield reflection 84 can occur inside the windshield 18. The light-transmitting redirecting element 54 can be configured in a manner described herein that can be operable with the display 12 to statically direct the collimated light 42 into the vertically narrow ray 25 such that its vertical cutoff angle 78 is less than the reflection angle θ4, thereby causing the vertically narrow ray 25 to generate the light signal 27 without a windshield reflection. The reflection angle θ4 is shown for non-limiting purposes with respect to generating a reflection from the windshield 18 because the reflection angle θ4 can vary and depend on the relative angle of the normal 68 with respect to the surface where reflection is undesirable. The reflection angle θ4, and therefore the cutoff angle 78, may vary depending on the spatial relationship between the display 12 and the surface that is intended to be non-reflective.

[0045] FIG. 7 shows a schematic diagram of another display 90 according to one non-limiting embodiment of the present disclosure. The display 90 may be similar to the display 12 described with respect to FIG. 2 , with the addition of a diffuser 92 disposed between the light-transmissive display element 24 and the backlight 26. The diffuser 92 may be a passive diffuser configured to spatially diffuse the vertically narrow light 25 emitted from the backlight 26 into diffused light 94, which may be emitted toward the light-transmissive display element 24. The diffused light 94 may include a diffusion angle consistent with the output angle θ2 from the backlight 26, and the diffused light 94 may have vertical and / or horizontal luminance profiles 74, 76 consistent with those described above with respect to FIG. 2 , although, optionally, the light 94 appears more spatially diffused. The diffuser 92 may optionally be an active diffuser, such as, but not necessarily limited to, a diffuser that can direct or control light passing therethrough in response to an electric field that aligns liquid crystals. However, passive diffusers may be preferred based on lower cost and less complexity.

[0046] As supported above, the backlight 26 contemplated by the present disclosure can be used with multiple display 12 configurations to generate a narrow vertical beam 25 to avoid causing reflections. The redirecting element 54, i.e., the prism 58, can be a fixed, immovable, or unalterable element useful for directing the collimated light 42 to generate the narrow vertical beam 25 without excessively wasting or rendering the collimated light 42 unusable. The redirecting element 54 can be optically transparent such that most, if not substantially all, of the collimated light 42 received therein passes through the light-transmissive display element 24. This relatively high transmission of the narrow vertical beam 25 to the light-transmissive display element 24 can minimize power consumption and maximize power efficiency, at least with respect to louvers, shutters, or other blocking elements or films configured to block the passage of light to or from the light-transmissive display element 24. The backlight 26 of the present disclosure may also be beneficial in that it may allow the display 12 to be positioned within the dashboard 14 without requiring the dashboard 14 to include an overhang or other cover that covers a portion of the display 12 or to include features to hide the display 12 from the windshield 18, i.e., the backlight 26 may allow the display 12 to be flush with and / or unobstructed by the dashboard 14, providing an aesthetically pleasing appearance while avoiding windshield reflections.

[0047] The terms "comprising," "including," and "having" include and thus define the presence of a stated feature, step, operation, element, or component, but do not exclude the presence or addition of one or more other features, steps, operations, elements, or components. The order of steps, processes, and operations can be changed where possible, and additional or alternative steps can be employed. As used herein, the term "or" includes any one and all combinations of the associated listed items. The term "any of" is understood to include any possible combination of the mentioned items, including "any one" of the mentioned items. "a," "an," "the," "at least one," and "one or more" are used interchangeably and indicate the presence of at least one of the items. More than one such item may be present unless the context clearly dictates otherwise. Unless otherwise expressly or unambiguously indicated in light of the context, including the appended claims, all numerical values ​​of parameters (e.g., numerical values ​​of amounts or terms) should be understood to be modified in all instances by the term "about," whether or not "about" actually precedes the numerical value. A component "configured to" perform a specified function is capable of performing the specified function without modification, rather than merely having the potential to perform the specified function after additional modification. In other words, the described hardware, when explicitly configured to perform the specified function, is specifically selected, made, implemented, utilized, programmed, and / or designed for the purpose of performing the specified function.

[0048] While various embodiments have been described, this description is intended to be illustrative rather than limiting, and it will be apparent to those skilled in the art that many more embodiments and implementations are possible within the scope of the embodiments. Any feature of any embodiment may be used in combination with or in place of any other feature or element in any other embodiment, unless specifically limited. Accordingly, the embodiments should not be limited except in light of the appended claims and their equivalents. Furthermore, various modifications and variations can be made within the scope of the appended claims. While several modes for implementing many aspects of the present teachings have been described in detail, those skilled in the art to which these teachings pertain will recognize various alternative modes for implementing the present teachings that are within the scope of the appended claims. All matter contained in the above description or shown in the accompanying drawings is intended to be illustrative and exemplary of the full range of alternative embodiments that one skilled in the art would recognize as structurally and / or functionally equivalent or otherwise obvious based on the content contained therein, and is not intended to be limited to only the embodiments explicitly depicted and / or described.

Claims

1. 1. A backlight system for preventing a display from causing windshield reflections inside a vehicle, the windshield reflections being caused by the display emitting light signals at a vertical angle greater than a reflection angle, the backlight system comprising: an edge light source configured to generate an edge light; a collimating light guide configured to collimate the edge light into a collimated light; a redirecting element statically configured to direct the collimated light into a narrow vertical beam having a vertical cutoff angle less than the reflection angle, the redirecting element operable with the display such that the narrow vertical beam generates the light signal without the windshield reflection; A backlight system comprising:

2. The redirecting element includes a plurality of prisms configured to redirect the collimated light into the vertically narrow light.

2. The backlight system according to claim 1.

3. The prism is triangular in shape and includes a light receiving surface configured to receive the collimated light, a reflecting surface configured to reflect the collimated light received from the light receiving surface, and an output surface configured to emit the vertically narrow light toward the display.

3. The backlight system according to claim 2.

4. The redirecting element is constructed from a light-transmitting material.

4. The backlight system according to claim 3.

5. The prism is fixedly attached to or included as part of the base of the redirecting element.

5. The backlight system according to claim 4.

6. The light receiving surface is configured to refract the collimated light before it reaches the reflecting surface.

6. The backlight system according to claim 5.

7. the light receiving surface is angled at a defined light receiving angle relative to a normal to the display; The reflective surface is angled at a reflection angle 6. The backlight system according to claim 5.

8. The light receiving surface cooperates with the reflecting surface to limit the vertically narrow light to an output angle that is smaller than the reflection angle.

8. The backlight system according to claim 7.

9. The collimating light guide is configured to emit the collimated light at a collimation angle substantially across the entire output face of the collimating light guide.

9. The backlight system according to claim 8.

10. The output face of the collimating light guide is parallel to the display and perpendicular to the normal.

10. The backlight system according to claim 9.

11. The surface area of ​​the output face is greater than the surface area of ​​the input to the collimating light guide that receives the edge light.

11. The backlight system of claim 10.

12. a diffuser disposed between the redirecting element and the display; Further provided with The diffuser is configured to spread the narrow vertical light into a diffused light to improve uniformity.

6. The backlight system according to claim 5.

13. The vertically narrow light is operable with the display to emit the light signal having a vertical luminance profile that is smaller than a horizontal luminance profile.

2. The backlight system according to claim 1.

14. The redirecting element is comprised of a light-transmitting material having a textured or shaped surface configured to direct the collimated light toward the display in a fixed manner without physically blocking the passage of the collimated light.

2. The backlight system according to claim 1.

15. 1. A backlight system for a display, comprising: an edge light source configured to generate an edge light; a collimating light guide configured to collimate the edge light into a collimated light; a plurality of triangular prisms statically configured to direct the collimated light into a narrow beam in a vertical direction; Equipped with The prism is configured to emit the narrow vertical light at a vertical cutoff angle defined relative to the normal to the display. A backlight system characterized by:

16. The prism includes a light receiving surface configured to receive the collimated light, a reflecting surface configured to reflect the collimated light received from the light receiving surface, and an output surface configured to emit the vertically narrow light toward the display.

16. The backlight system of claim 15.

17. The redirecting element is comprised of a light-transmitting material configured to direct the collimated light toward the display in a fixed manner without physically blocking the passage of the collimated light.

17. The backlight system of claim 16.

18. A vehicle, The windshield and a display positioned behind and below at least a portion of the windshield, the display producing a windshield reflection when emitting an optical signal at a vertical angle greater than the reflection angle; a backlight system configured to prevent the display from causing windshield reflections; Equipped with The backlight system comprises: a collimating light guide configured to collimate the input light into a collimated light; a light-transmissive redirecting element configured to statically redirect the collimated light into a narrow vertical beam having a vertical cutoff angle less than the reflection angle; and The vertically narrow light is operable with the display to generate the light signal without the windshield reflection. A vehicle characterized by:

19. The redirecting element includes a textured or shaped surface configured to statically direct the collimated light toward the display in a fixed manner without physically blocking the passage of the collimated light.

20. The vehicle of claim 18.

20. The redirecting element includes a plurality of prisms configured to statically direct the collimated light toward the display in a fixed manner without physically blocking the passage of the collimated light.

20. The vehicle of claim 18.

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