LED retrofit lamp for use in projector-type motor vehicle headlight system

Abstract

An LED retrofit lamp (400) for a projection headlight system includes a heat dissipating body portion (440) and a substantially rectangular substrate (330). The first LED group (310) is mounted on a first surface of the substrate (330) and the second LED group (310) is mounted on a second surface. The support bracket (450) is configured to engage longitudinal sides of the substrate (330) to mechanically support the substrate (330) in alignment with a central optical axis of the headlight system such that light emitted by the first and second LED groups (310) parallel to the first and second surfaces illuminates corresponding top and bottom segments of the cooperating reflectors at sufficient intensity, the projection headlight system forms a light beam with substantially uniform light intensity.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 325,383, filed on March 30, 2022, the contents of which are hereby incorporated by reference. Background Art

[0003] Light emitting diode (LED) retrofit lamps may be used as aftermarket replacements for halogen lamps in automotive headlamp systems. The term LED retrofit may generally refer to an LED lamp assembly that provides the headlamp lighting function previously provided by a halogen lamp. In such retrofit lamps, the LEDs may be placed in a location close to where the filament would be in the halogen lamp. In many retrofit lamps, two groups of LEDs may be placed on opposite sides of a printed circuit board (PCB). When used in an automotive headlamp system, the LED groups may be projected, and ideally, the projected outline of the LED groups may coincide with the projected contour of the filament when viewed perpendicular to the top surface of the LEDs. The light emissions of such LED groups may ideally be back-to-back. Summary of the invention

[0004] An LED retrofit lamp for a projector headlight system includes a heat dissipating body portion and a substantially rectangular substrate. A first LED group is mounted on a first surface of the substrate, and a second LED group is mounted on a second surface. A support bracket is configured to engage a longitudinal side of the substrate to mechanically support the substrate in alignment with a central optical axis of the headlight system so that light emitted by the first LED group and the second LED group parallel to the first surface and the second surface illuminates corresponding top and bottom segments of a cooperating reflector with sufficient intensity to allow the projector headlight system to form a light beam with substantially uniform light intensity. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] A more detailed understanding may be obtained from the following description, which is given by way of example in conjunction with the accompanying drawings, in which:

[0006] Figure 1 is a perspective view of an example LED retrofit lamp;

[0007] Figure 2 yes Figure 1 A perspective view of a distal portion of an example LED retrofit lamp;

[0008] Figure 3 It is installed in the projector headlight system Figure 1 and Figure 2 A side view of an example LED retrofit lamp;

[0009] Figure 4 is a perspective view of another example LED retrofit lamp;

[0010] Figure 5 yes Figure 4 an enlarged view of a portion of an example LED retrofit lamp; and

[0011] Figure 6 is a perspective view of another example LED retrofit lamp;

[0012] Fig. 7A is a pictorial perspective view of an example LED package;

[0013] Figure 7B yes Fig. 7A a diagrammatic side view of an example LED package;

[0014] Figure 7C yes Fig. 7A Luminous intensity graph of an example LED package;

[0015] Fig. 8A is a diagrammatic perspective view of another example LED package;

[0016] Figure 8B yes Fig. 8A a diagrammatic side view of an example LED package;

[0017] Figure 8C yes Fig. 8A Luminous intensity graph of an example LED package;

[0018] Fig. 9A is a diagrammatic perspective view of another example LED package;

[0019] Fig. 9B yes Fig. 9A a diagrammatic side view of an example LED package of; and

[0020] Fig. 9C yes Fig. 9A Luminous intensity graph of an example LED package. DETAILED DESCRIPTION

[0021] Examples of different light illumination systems and / or light emitting diode (LED) embodiments will be described more fully below with reference to the accompanying drawings. These examples are not mutually exclusive, and features found in one example can be combined with features found in one or more other examples to achieve additional embodiments. Therefore, it will be understood that the examples shown in the accompanying drawings are provided for illustrative purposes only, and they are not intended to limit the present disclosure in any way. Like numbers always refer to like elements.

[0022] It will be understood that although the terms first, second, third, etc. can be used to describe various elements in this article, these elements should not be limited by these terms. These terms can be used to distinguish an element from another element. For example, the first element can be referred to as the second element and the second element can be referred to as the first element without departing from the scope of the present invention. As used herein, the term "and / or" can include any and all combinations of one or more associated listed items.

[0023] It will be understood that when an element such as a layer, region, or substrate is referred to as being "on" or "extending to" another element, it may be directly on or directly extending to another element, or there may also be intermediate elements. In contrast, when an element is referred to as being "directly on" or "directly extending to" another element, there may be no presence of intermediate elements. It will also be understood that when an element is referred to as being "connected" or "coupled" to another element, it may be directly connected or coupled to another element and / or connected or coupled to another element via one or more intermediate elements. In contrast, when an element is referred to as being "directly connected" or "directly coupled" to another element, there is no presence of intermediate elements between the element and the other element. It will be understood that these terms are intended to cover different orientations of elements in addition to any orientation depicted in the figures.

[0024] Relative terms such as "below," "above," "upper," "lower," "horizontal," or "vertical" may be used herein to describe the relationship of one element, layer, or region to another element, layer, or region illustrated in the figures. It will be understood that these terms are intended to encompass different orientations of the device in addition to the orientation depicted in the figures.

[0025] LED retrofits have gained popularity as aftermarket replacements for halogen lamps in both reflector and projector type automotive headlamp systems. The term LED retrofit may generally refer to an LED lamp assembly that provides the headlamp lighting function previously provided by a halogen lamp. The mounting structure of the LED retrofit lamp is configured to be compatible with the mounting structure for the corresponding halogen type lamp.

[0026] Ideally, the profile of the light emitted by an LED retrofit lamp would replicate the profile of a corresponding halogen lamp. However, the glowing filament in a halogen lamp emits light in all directions, with little to no dark space at the point of emission. In contrast, the LED light emitters in LED retrofit lamps are typically mounted on one side of a printed circuit board. As a result, the emitted light may not have a profile that ideally matches the profile of the filament in the halogen lamp. For example, an LED lamp may emit light from one side of a circuit board and not emit light from the other side. Regardless of whether the LED retrofit lamp is placed in a reflector or projector-type headlamp system, a one-sided light emission profile can negatively impact the performance of the headlamp.

[0027] Figure 1 is a perspective view of an exemplary LED retrofit lamp 100. Figure 1 In the example shown in , the LED retrofit lamp 100 includes a heat sink body portion 170 and a bracket 150. The bracket 150 can provide mechanical support and stability for the substrate 130. The substrate 130 can be or include a printed circuit board (PCB). The bracket 150 can include an elongated first bracket arm 120A and an elongated second bracket arm 120B extending from the heat sink body portion 170 to define the longitudinal axis of the LED retrofit lamp 100. A cap portion (not labeled) can connect the first and second bracket arms at the proximal end of the bracket 150 and can couple the bracket 150 to the heat sink body portion 140. The cap portion can be a separate part or component of the heat sink body portion and / or the bracket 150.

[0028] The base plate 130 may be substantially rectangular in shape and disposed between the first and second support arms 120A and 120B. Figure 1 The second longitudinal edge of the base plate 130 (not visible in FIG. 1 ) may engage a corresponding slot formed in the support arm 120A. Figure 1 (not visible) can engage a corresponding slot formed in the bracket arm 120B.

[0029] The first LED package 110 may include a first group of light emitters and may be mounted on one side of the substrate 130. The second LED package ( Figure 1 ) may include a second set of light emitters and may be mounted on the opposite side of substrate 130 ( Figure 1 The LED package can be arranged on the substrate 130 so as to emit light from substantially the same position within the LED retrofit lamp 100 as the filament would be positioned in a corresponding halogen lamp. Figure 1 As indicated by the dotted arrows in , light may be emitted from both sides of the substrate 130 from one side to the other side.

[0030] The LED packages 110 may be mounted on either side of the substrate 130 so that when mounted, their non-light emitting surfaces may be substantially back-to-back with the substrate 130 interposed therebetween. Ideally, when the LED retrofit lamp 100 is mounted in a vehicle headlamp system, the projected outline profile of the first and second groups of LEDs in the back-to-back arrangement may coincide with the projected outline line of the filament in the corresponding halogen lamp when viewed perpendicular to the top surface of the LEDs.

[0031] Figure 2 yes Figure 1 FIG. 1 is a side view of a distal portion of a bracket 150 of an LED retrofit lamp 100. The bracket 150 may be provided on a reflector structure ( Figure 2A support substrate 130 is provided in a central region of the reflector structure (not shown), and the reflector structure may include, for example, a reflector-type vehicle headlight system (the complete system is not shown). Figure 1 The orientation of the bracket 150 is shown, and therefore the orientation of the primary light emitting surface of the LED package 110 relative to the ground on the opposite side of the substrate when viewed in a typical operating orientation when installed in a headlight system of a vehicle (not shown), wherein the vehicle's wheels rest on the ground.

[0032] exist Figure 2 In the orientation shown in , the vehicle floor would be defined as "down" and the roof would be defined as "up". Thus, "bottom" or "downward" is toward the vehicle floor, and "top" or "upward" is toward the roof. In this orientation, the primary light emitting surfaces of the back-to-back LED packages 110 can emit light in opposite directions from opposite sides of the substrate 130. Light can be emitted from the respective substrate sides in directions that would correspond to the sides of the vehicle, where, for example, the driver's side door would define one side of the vehicle and the passenger's side door would define the other side of the vehicle. In this orientation, a substantial portion of the light emitted from the LED package 100 can be emitted laterally (i.e., in a direction horizontal to the ground plane).

[0033] like Figure 2 As shown in FIG. 1 , the support 150 can hold the substrate 130 in the reflector structure ( Figure 2 The reflector structure may be part of a vehicle headlight system (not shown). Light emitted from the main light emitting surface of the LED package 110 may be emitted primarily in a direction indicated by an arrow (dashed arrow) toward a corresponding segment of the reflector, which may be on an opposite side of the reflector structure and may be close to a horizontal plane including an optical system of the headlight system (e.g., a plane horizontal to the plane of the top and bottom surfaces of the substrate 130).

[0034] Configuration (such as Figure 2 The configuration shown in ) may perform particularly well in a reflector-type headlamp system. In such a headlamp system, a major portion of the headlight beam may be produced by reflector segments that are close to the horizontal plane of the optical system. These segments may cooperate to produce a smooth beam with good range in a significant portion of the headlight beam, which is approximately 25m to 100m in front of the vehicle. On the other hand, the reflector segments above and below the retrofit lamp 100 may make only a limited contribution to the headlight beam formation in a reflector-type headlamp system. In such a configuration, it may be acceptable for the first and second groups of LED emitters not to emit light toward the top and bottom reflector segments. Such an emission pattern may even be beneficial because more light may be emitted toward the associated horizontal reflector segments.

[0035] Figure 3 yes Figure 1and Figure 2 8 is a side view of an LED retrofit lamp 100, as shown, disposed within a projector-type vehicle headlamp system 800. In this view, the elevation is vertical (top to bottom) orthogonal to the horizontal ground plane. Like a reflector-type headlamp system, the projector-type headlamp system 800 includes a reflector structure 850. The projector headlamp system 800 may further include a lens 820.

[0036] As mentioned above about Figure 2 As described above, the main light emitting surface of the LED package 110 can emit light from each side of its substrate 130 toward each corresponding opposite reflector segment side (not shown) of the reflector 850. The reflector 850 can reflect light toward the focal area 805 (by Figure 3 ). Lens 820 can collect light from the focal area to form a headlight beam and project the headlight beam outward from the front of the vehicle. Unlike a reflector type headlight system, in a projector type headlight system (such as Figure 3 In a projector-type headlamp system 800), the lack of light toward the top and bottom segments of the reflector 850 can translate into non-uniformity of light comprising the headlight beam projected outward in front of the vehicle, particularly in the center region of the beam.

[0037] The performance of the optical system in a projector-type headlamp system may also be affected by the distance that the LED emitters on either side of the substrate are displaced from the nominal filament position. The greater the apparent spacing between the back faces of the back-to-back LED packages, the further each chip may be displaced from the nominal filament position. For this reason, it may be desirable to form the substrate 130 as thin as possible. The thinner the substrate is placed between the back faces of the back-to-back LED packages, the closer the back faces of the LED packages are to each other, and the closer each chip is to the nominal filament position.

[0038] On the other hand, if the substrate 130 is too thin, sufficient mechanical stability may not be provided when the LED package 110 is mounted on the substrate 130. Therefore, an LED bracket (such as Figure 1 and Figure 2 The bracket 150 shown in FIG. 1 is provided to mechanically support and stabilize the substrate to which the LED package 110 can be mounted. In order to firmly engage and support the edge of the substrate between the bracket arms of the bracket, the width of the bracket arms should be wider than the thickness of the substrate. This can be achieved in FIG. Figure 1 Seen in Figure 1 In the embodiment, the substrate is arranged between the support arms by engaging the edge of the substrate with a groove extending along the longitudinal axis of each support arm. The portion of each support arm above and below the corresponding groove makes the width of the support arm wider than the thickness of the substrate.

[0039] As described above, the greater the spacing between the back faces of the back-to-back LED packages 110, the further the LED packages are from the nominal filament position. Reducing the thickness of the substrate can reduce the actual spacing distance between the back faces of the LED packages 110. However, when looking down at the bracket from above the bracket (i.e., in a top view of the bracket 150) to see the emitted light, the width of the bracket arms themselves can increase the apparent distance between the back faces of the back-to-back LEDs.

[0040] Due to the thickness of the first and second bracket arms, light emitted at a small angle relative to the top surface of the LED group including the LED package 110 can be blocked by part of the bracket arm. In this case, the bracket arm can produce an area with no light intensity or very low light intensity, which is larger than the area that would be produced by the substrate itself without the bracket. Therefore, the bracket supporting the substrate 130 may impair the performance of the LED retrofit light source in the projector system.

[0041] Figure 4 is a perspective view of an example of an LED retrofit lamp 400. Figure 4 In the example shown in FIG. 4 , the LED retrofit lamp 400 includes a heat sink body portion 440 and a bracket 450 configured to support a substrate 330. In the example herein, the substrate 330 may be or include a printed circuit board (PCB). A first LED package 310, which may include a first group of LED light emitters (not separately depicted), may be mounted on one side of the substrate 330. A second LED package 310 ( Figure 4 can be mounted on the other side of the substrate 330 ( Figure 4 The first and second LED packages 310 may be mounted back to back. In this arrangement, the substrate 330 may separate the back side of the first LED package 310 from the back side of the second LED package 310 by an actual distance that is substantially equal to the thickness of the substrate 330.

[0042] The bracket 450 may include a first elongated bracket arm 420A and a second elongated bracket arm 420B extending from a cap portion ( 420B ) between the bracket 450 and the heat sink body portion 440. Figure 4 The cap may extend from the bracket 450 to the heat sink body 440 to define a longitudinal axis of the LED retrofit lamp 400. As described above, the cap may couple the bracket 450 to the heat sink body 440. Unlike the bracket 150 of the LED retrofit lamp 100, the bracket 450 of the LED retrofit lamp 400 may be configured according to the teachings herein to improve the performance of the LED retrofit lamp 400 compared to the LED retrofit lamp 100 when the performance is compared in a projector-type headlamp system.

[0043] exist Figure 4In the exemplary configuration shown in , light 22 emitted by LED package 310 propagates outwardly through the middle portion of bracket 450 between the proximal and distal portions of the first and second bracket arms. This light can be emitted both upward and downward. In a projector-type headlamp system, light emitted upward or downward may have a more significant contribution to the beam pattern. Figure 4 The configuration provides more light to these parts of the optical system, which alleviates the problem of non-uniformity in the projection beam pattern (especially in the central part).

[0044] The performance of these parts of the optical system may also be affected by the distance of the LEDs from the nominal filament position (i.e., the distance of the top emitting areas of the two sets of LEDs). Figure 4 The configuration maintains an apparent spacing between the back faces of the back-to-back LED packages 310 that is substantially the same as the actual spacing. The actual spacing may be a distance between the back faces of the back-to-back LED packages that corresponds to the thickness of the substrate 330 disposed between the back faces of the LED packages 310. The smaller the spacing between the LED packages (whether apparent or actual), the closer the profile of the light emitted by the LED packages of the lamp 400 is to the profile of the light emitted by the filament of the corresponding halogen lamp.

[0045] Figure 5 yes Figure 4 An enlarged perspective view of the bracket shown in FIG. Figure 5 As shown in FIG, the bracket 500 includes a first (upper) bracket arm 520A and a second (lower) bracket arm 520B. The bracket 450 can engage the base plate 530 at corresponding proximal and distal longitudinal edges of the base plate 530.

[0046] The first support arm 520A and the second support arm 520B can each include a proximal end 526A and 526B, a distal end, and an intermediate portion. In this example, the proximal edge of the base plate 530 engages with corresponding grooves 24A and 24B formed in the proximal and distal portions of the first and second support arms 520A and 520B. Each groove can extend along the longitudinal axis 13 of the corresponding proximal and distal portions of the first and second support arms 520A and 520B.

[0047] The middle portions 30A and 30B may extend between the proximal portions of the support arms 520A and 520B and the distal portions of the support arms 520A and 520B. The proximal portions of the support arms 520A and 520B may each include curved portions 15A, 15B, which may be connected to the corresponding proximal ends of the middle portions 30A and 30C. Similarly, the distal portions of the support arms 520A and 520B may each include curved portions 15C and 15D, which may be connected to the distal ends of the middle portions 30A and 30B. The middle portions 30A and 30B of the first and second support arms 520A and 520B may have a height substantially the same as the thickness of the base plate 530. In this way, the support arms 520A and 520B will not block the light emitted by the LED 510 in the lateral direction 12, and the support arms 520A and 520B can have a maximum height h defined by the top surfaces 10A and 10B of the support arms 520A and 520B. The middle portions 30A and 30B can contact the corresponding middle longitudinal edges of the substrate 530 at the corresponding middle portions of the substrate 530.

[0048] Because the middle portion of the support arm in this area may have the same height as the thickness of the substrate, the support arm in the middle portion may not protrude above the top surface of the substrate 530 or below the bottom surface of the substrate 530. Therefore, the apparent spacing between the back surfaces of the back-to-back LED packages 510 may be substantially the same as the actual spacing, which is the thickness of the substrate 530 in the area of ​​the middle portions 30A and 30B. This may provide the LED retrofit lamp 500 with an illumination profile that is closer to that of a filament in a corresponding halogen lamp when compared to the illumination profile provided by the support 150 of the retrofit lamp 100.

[0049] The bent portions 15A, 15B, 15C, and 15D on both the top and bottom surfaces of each bracket arm may form a light-shaping opening through which light emitted by the LED package 510 may pass near the planes of the top and bottom surfaces of the substrate 530. The bracket arms 520A and 520B may be configured relative to the LED package 510 and the substrate 530 so that the light-shaping openings may be aligned with the light-emitting portions at the sides of the LED package 510. When the LED retrofit lamp 500 is installed in a headlamp system of a vehicle, the light-shaping openings in the bracket arms may be at the top and bottom of the LED retrofit lamp 500. Light may propagate through the light-shaping openings to illuminate the corresponding top and bottom segments of the reflector 800.

[0050] When the LED retrofit lamp 500 is installed in a projector type headlamp system, the LED retrofit lamp 500 is installed in a projector type headlamp system. Figure 1 The bracket configuration described in detail above may provide an improved headlight beam compared to the headlight beam provided by the LED retrofit lamp 100 shown in FIG. 1 installed in a projector-type headlight system.

[0051] Figure 6 6 is a perspective view of an LED retrofit lamp 600 according to another example. The LED retrofit lamp 600 may include a heat sink body portion 640 and a bracket 650 supporting a substrate 630. A first LED package 610 including a first group of LED light emitters (not separately depicted) may be mounted on one side of the substrate 630. A second LED package ( Figure 6 can be mounted on the other side of the substrate 630 ( Figure 6 The first and second LED packages 610 can be mounted back to back. In this arrangement, the substrate 630 separates the back side of the first LED package from the back side of the second LED package by an actual distance that is substantially equal to the thickness of the substrate 630.

[0052] The bracket 650 may include a first elongated bracket arm 620A and a second elongated bracket arm 620B extending from a cap portion 627 to define a longitudinal axis of the LED retrofit lamp 600 having the heat sink 640. The cap 627 may couple the bracket 650 to the heat sink 640. Proximal portions of the first bracket arm 620A and the second bracket arm 620B may be configured to have a height that extends beyond a surface of the substrate 630. Distal portions of the first and second bracket arms 620A and 620B may have a height that is substantially the same as a thickness of the substrate 630.

[0053] Because the distal end portion of the support arm has the same height as the thickness of the substrate, the support arm at the distal end portion may not protrude above the top surface of the substrate 650 or below the bottom surface of the substrate 650. Therefore, the apparent spacing between the back surfaces of the back-to-back LED packages 610 will be substantially the same as the actual spacing, which is the thickness of the substrate 650 in the region of the distal end portion. This can provide the LED retrofit lamp 600 with an illumination profile that is closer to that of a filament in a corresponding halogen lamp when compared to the illumination profile provided by the support 150 of the retrofit lamp 100.

[0054] A bent portion 15A, 15B may be formed on the top surface of each of the support arms 620A and 620B. Figure 6 A curved portion (not visible in the figure) may be formed on the bottom surface of each of the support arms 620A and 620B. The curved portion may be inclined downward from the top of the proximal portion of the first and second support arms to meet the corresponding distal portion of the first and second support arms. The curved portion may form a light-shaping opening at the distal end of the LED retrofit lamp 600, through which light emitted by the LED package 610 may pass near the plane of the top and bottom surfaces of the substrate 620.

[0055] The bracket arms 620A and 620B may be configured relative to the LED package 610 and the substrate 630 so that the light shaping openings at the distal ends of the bracket arms are aligned with the light emitting portions at the sides of the LED package 610. When the LED retrofit lamp 600 is installed in a headlamp system of a vehicle, the light shaping openings in the bracket arms may be at the top and bottom of the LED retrofit lamp 600. Light may propagate through the light shaping openings to illuminate the corresponding top and bottom segments of the reflector 800.

[0056] When the LED retrofit lamp 600 is installed in a projector type headlamp system, Figure 1-Figure 3 The bracket configuration described in detail above may provide an improved headlight beam compared to the headlight beam provided by the LED retrofit lamp 100 shown in FIG. 1 installed in a projector-type headlight system.

[0057] In some embodiments, the above-mentioned LED retrofit lamp includes an LED light source, which is configured to cooperate with any one of the bracket configurations, so that when the LED retrofit lamp is installed in a projector-type vehicle headlamp system and when viewed perpendicular to the top surface of the LEDs, the projected outline shape of the first group and the second group of LEDs in the back-to-back arrangement closely coincides with the projected outline line of the filament in the corresponding halogen lamp.

[0058] Fig. 7A is a perspective view of an LED package 700 configured for an LED headlamp application, and Figure 7B 706 and 703b, and are side views of LED packages 700. LED packages 700 generally include a blue-light-emitting LED chip 711 disposed on an LED substrate 706 and covered with a phosphor layer 712 that converts a portion of the blue light from the LED chip 711 into yellow light. The combination of light output from the blue LED chip 711 and the converted yellow light from the phosphor layer 712 results in white light emission. This white light is particularly emitted from a top surface 704 of the phosphor layer 712. Such LED packages may include a side coating or other barrier 707 that is designed to block light emitted from the blue LED chip 711 and the phosphor layer 712 in a direction substantially perpendicular to the sides 703a, 703b, 703c, and 703d of the LED substrate (i.e., in a direction substantially parallel to a horizontal axis 708 of the LED package 700). Side coating seals: the sides of the blue LED chip 711, which may have a thickness of, for example, 0.1-0.2 mm; and the phosphor layer 712, which may add another 0.1-0.2 mm of thickness. Fig. 7A In the example, the exposed phosphor surface 704 is 3×1×1 mm 2 area.

[0059] The purpose of blocking light emission in or below the top surface plane 708 (i.e., blocking light emission parallel to lines perpendicular to the side surfaces 703a, 703b, 703c, and 703d) is to support the optical (LED) headlamp designer by providing a light source with high contrast between the light emitting portion of the headlamp and the surrounding structural elements. In addition, such side coatings increase the amount of useful light available to the light emitting portion of the headlamp and avoid stray light in LED headlamp optics that are designed to use primarily the emission from the top surface of the LED package. This results in a sharp cutoff of the headlamp beam and avoids glare to oncoming traffic.

[0060] Figure 7C 7 is a luminous intensity graph 750 showing example luminous intensity of LED package 700 at different emission angles relative to a vertical axis 709 of the LED package 700. The graph shows that the luminous intensity is 100% of the maximum value at 0 degrees relative to the vertical axis 709 of the chip 700, and the luminous intensity is 0% of the maximum value at an angle of + / - 90 degrees relative to the vertical axis 709 of the chip 700 (i.e., parallel to the horizontal axis 708).

[0061] Fig. 8A An example LED package 1800 is depicted. The LED package 1800 is configured to have a wider range of light emission. In other words, the LED package 1800 is configured to emit light at a non-zero percentage of the maximum luminous intensity even at a 90 degree angle relative to the vertical axis 1809 of the LED package 1800. This can be achieved, for example, by applying a phosphor around the top surface 1804 of the chip 1800 and at the edges of the LED package 1800. In this example method, the light emitted by the LED of the chip 1800 can excite the phosphor coating at the top and edges to cover the LED package 1800 in blue light. This achieves some significant light emission to the sides of the LED package, such as light emitted by ignition of the phosphor at the sides 1803a and 1803b of the LED package 1800.

[0062] Figure 8B 18 is a side view of an LED package 1800 disposed on a substrate 1806. Fig. 7A Unlike the typical LED package 700 shown in FIG. 1 , the LED package 1800 does not have any coating or barrier at the side 1803 to block light from propagating away from the sides 1803a and 1803b. Fig. 8A and Figure 8B In the configuration, there is nothing preventing light from propagating in a direction parallel to the horizontal axis 1808 or at a small angle relative to the horizontal axis 1808. Figure 8BAn example emission pattern 1810 is shown in which light propagates at a small angle relative to a horizontal plane defined by the top emitting surface of LED 1800 (extending along horizontal axis 1808 ), or in other words, at a large angle relative to vertical axis 1809 .

[0063] Figure 8C is a luminous intensity graph 1850 showing the LED package 1800 relative to Fig. 8A and Figure 8B 1809. The graph shows luminous intensity at different emission angles relative to the vertical axis 1809 at 0 degrees, which is 100% of the maximum luminous intensity. In other words, light emitted substantially parallel to the vertical axis 1809 will have maximum luminous intensity. Importantly, light emitted from the sides 1803a and 1803b at small angles relative to the horizontal axis 1808 (and at large angles relative to the vertical axis 1809) will have some luminous intensity (indicated at 1841). For example, light emitted at approximately -90 degrees relative to the vertical axis 1809 has some luminous intensity (indicated at 1842). Similarly, light emitted at approximately +90 degrees relative to the vertical axis 1809 will have some luminous intensity (indicated at 1842). In other words, light will be emitted with at least some luminous intensity in a direction that is substantially parallel to the horizontal axis 1808 and close to the horizontal plane of the chip 1800. Fig. 8A and Figure 8B In one example of LED 1800 shown in FIG, the luminous intensity is approximately 5% of the maximum value at 1841 (i.e., approximately -90 degrees relative to the vertical axis 1809, and also at 1842, which is approximately +90 degrees relative to the vertical axis 1809). However, this percentage can vary based on the configuration of the LED package. An important feature of chip 1800 is to emit light sideways so as to allow the emitted light to propagate from chip 1800 at a small angle relative to the horizontal axis 1808.

[0064] Embodiments described herein include LED retrofit lamps that include any of the LED brackets described herein, equipped with a light source 1800 configured as described above. In these combinations of brackets and LED packages 1800, the LED packages are arranged relative to the openings in the bracket arms so that light can propagate laterally (i.e., away from the sides 1803a and 1803b of the LED packages 1800 and through corresponding openings in the bracket arms of the LED retrofit lamp bracket). The light propagates at an angle that is close to (e.g., substantially parallel to) the horizontal plane in which the top surface of the LED package 1800 lies. This allows illumination of the top and bottom segments of the reflector component of the projection headlamp system, thereby providing the top and bottom reflector components with light of sufficient intensity to project a headlight beam characterized by substantially uniform light intensity. The bracket arms of the brackets described herein are configured to pass light propagating at these smaller angles while supporting and stabilizing the substrate relative to the optical axis of the headlamp system.

[0065] Fig. 9A and Fig. 9B Another type of LED 900 is shown. The LED package 900 can have a phosphor (which produces blue light) extending over the edges of the LED chip (e.g., 903a, 903b), resulting in a brighter LED than Fig. 8A and Figure 8B The sideways emission of LED 1800 shown in FIG. 9 is smaller. However, LED 900 still has a relevant sideways (ie, parallel to horizontal plane 903) emission. Fig. 9B 900. The sides 903a and 903b of the LED package 900 are substantially free of side coatings or barriers that would block light from propagating away from the sides 903a and 903b. Fig. 9A and Fig. 9B In the configuration, at least some of the light can propagate in a direction parallel to the horizontal axis 908 and at a small angle relative to the horizontal axis 908. Fig. 9B An example emission pattern 910 is shown in which light propagates at small angles relative to the horizontal axis 908 at sides 903a and 903b.

[0066] Fig. 9C is a luminous intensity graph 950 showing the luminous intensity of the LED package 900 relative to Fig. 9A and Fig. 9B The luminous intensity at different emission angles with respect to the vertical axis 909 in FIG. The figure shows that the maximum luminous intensity is 100% at 0 degrees relative to the vertical axis 909. In other words, light emitted substantially parallel to the vertical axis 909 will have the maximum intensity.

[0067] For example, Fig. 9A and Fig. 9BAs shown in , the luminous intensity is a small but non-zero percentage of the maximum intensity at positive 90 degrees and negative 90 degrees relative to the vertical axis 909, corresponding to emission away from the sides 903a and 903b in a direction parallel to the horizontal axis 908. In some examples, the luminous intensity is between approximately 1% and 3% of the maximum luminous intensity at approximately positive 90 degrees and negative 90 degrees relative to the vertical axis 909. However, these percentages on either side can vary based on the construction of the LED die and its package. An important feature of chip 900 is that its configuration allows some light to propagate from the sides of LED 900 at lower angles relative to the horizontal axis 908.

[0068] Having described the embodiments in detail, it will be appreciated by those skilled in the art that, given this description, the embodiments described herein may be modified without departing from the spirit of the present disclosure concept. It is therefore intended that the scope of the present disclosure is not limited to the specific embodiments illustrated and described, but that the scope of protection is limited only by the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "a" or "an" does not exclude a plurality. The mere fact that certain measures are cited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be interpreted as limiting the scope.

Claims

1. An LED retrofit lamp for replacing a corresponding halogen lamp in a projector headlamp system, the projector headlamp system comprising a reflector and a lens, the reflector comprising a top reflector segment, a bottom reflector segment, a first side reflector segment and a second side reflector segment, the LED retrofit lamp comprising: Heat dissipation main body; a substrate comprising a first substrate surface spaced a distance from a second substrate surface to define a longitudinal substrate side and a lateral substrate side, the distance defining a substrate height; a first LED group mounted on the first surface and a second LED group mounted on the second surface; A support bracket configured to engage the longitudinal substrate side to mechanically support the substrate to align with the central optical axis of the reflector so that light emitted by the first LED group and the second LED group perpendicular to the first substrate surface and the second substrate surface illuminates the corresponding first side reflector segment and the second side reflector segment, and light emitted parallel to the first reflector surface and the second reflector surface illuminates the corresponding top reflector segment and the bottom reflector segment with sufficient intensity to enable the lens to project a headlight beam having a substantially uniform light intensity. 2 . The LED retrofit lamp according to claim 1 , wherein the first LED group and the second LED group are respectively located on the first substrate surface and the second substrate surface close to positions corresponding to filaments in the halogen lamp.

3. The LED retrofit lamp according to claim 1, wherein the bracket includes a first slender bracket arm and a second slender bracket arm, each bracket arm includes a proximal arm portion, and the proximal arm portion has an inner surface providing a first longitudinally extending groove to engage the corresponding longitudinal side of the substrate between the first bracket arm and the second bracket arm, thereby supporting the proximal end of the substrate.

4. The LED retrofit lamp of claim 3, wherein each of the first bracket arm and the second bracket arm comprises an elongated distal arm portion having an arm height approximately equal to a height of the base plate, so that light emitted parallel to the first surface and the second surface illuminates the corresponding top reflector segment and the bottom reflector segment with sufficient intensity to enable the lens to project a headlight beam having a substantially uniform light intensity.

5. The LED retrofit lamp according to claim 3, wherein each of the first bracket arm and the second bracket arm includes an elongated distal arm portion having an inner surface providing a second longitudinally extending groove to engage a corresponding longitudinal side of the substrate between the first bracket arm and the second bracket arm to support a distal end of the substrate.

6. The LED retrofit lamp of claim 5, wherein each of the first support arm and the second support arm includes an intermediate arm portion extending between the proximal arm portion and the distal arm portion, and an arm height of the intermediate arm portion is approximately equal to the height of the substrate, so that light emitted parallel to the first surface and the second surface illuminates the corresponding top reflector segment and the bottom reflector segment with sufficient intensity to enable the lens to project a headlight beam with substantially uniform light intensity. 7 . The LED retrofit lamp according to claim 5 , wherein at least a portion of the LEDs comprising the first LED group and the second LED group are configured to emit light laterally substantially parallel to a lateral axis of the first surface and the second surface.

8. The LED retrofit lamp according to claim 1, wherein the first LED group and the second LED group include corresponding first LED packages and second LED packages, each of the first LED packages and the second LED packages being configured to emit light at a maximum luminous intensity of approximately 100% in a direction away from the substrate and parallel to a vertical axis of the first LED package and the second LED package, and to emit light with a luminous intensity greater than 0% at an angle close to 90 degrees to the vertical axis and substantially parallel to a horizontal axis of the LED package, so that light emitted substantially parallel to the horizontal axis passes through corresponding openings in the bracket, thereby illuminating the corresponding top reflector segment and bottom reflector segment with sufficient luminous intensity to enable the lens to project a headlight beam having a substantially uniform luminous intensity.

9. The LED retrofit lamp of claim 8, wherein the first LED package and the second LED package are configured to emit light in a direction substantially parallel to a horizontal axis with a relative luminous intensity of between at least about 1% and about 5% of a maximum luminous intensity.

10. An LED retrofit lamp bracket for supporting a substrate in a projection headlamp system, the substrate comprising: a first surface carrying a first LED group and a second surface carrying a second LED group, the first surface being spaced apart from the second surface so as to define a longitudinal substrate side and a lateral substrate side, the distance defining a substrate height, and the projector front light system comprising a reflector, the reflector comprising a top reflector segment, a bottom reflector segment, a first side reflector segment, and a second side reflector segment, the bracket comprising: coupling the substrate to a cap portion of a heat sink; and A first slender support arm and a second slender support arm extend from the cap portion and are configured to: engage the longitudinal sides of the substrate to mechanically support the substrate to align with the central optical axis of the reflector; transmit light emitted by the first LED group and the second LED group perpendicular to the first surface and the second surface to the reflector to illuminate the corresponding first side reflector segment and the second side reflector segment; and transmit light emitted parallel to the first surface and the second surface to the reflector to illuminate the corresponding top reflector segment and the bottom reflector segment with sufficient intensity so that the headlight system forms a headlight beam with substantially uniform light intensity.

11. The LED retrofit lamp bracket according to claim 10, wherein each of the first slender bracket arm and the second slender bracket arm includes a slender proximal arm portion, the proximal arm portion having an inner surface providing a first longitudinally extending groove to engage the corresponding longitudinal side of the substrate between the first bracket arm and the second bracket arm, thereby supporting the proximal end of the substrate.

12. The LED retrofit lamp bracket according to claim 11, wherein each of the first bracket arm and the second bracket arm includes an elongated distal arm portion, and the arm height of the distal arm portion is approximately equal to the height of the substrate, so that light emitted parallel to the first surface and the second surface illuminates the corresponding top reflector segment and the bottom reflector segment with sufficient intensity to enable the headlight system to form a headlight beam with substantially uniform light intensity.

13. The LED retrofit lamp bracket according to claim 11, wherein each of the first bracket arm and the second bracket arm includes an elongated distal arm portion having an inner surface providing a second longitudinally extending groove to engage the corresponding longitudinal side of the substrate between the first bracket arm and the second bracket arm, thereby supporting the distal end of the substrate.

14. A bracket according to claim 13, wherein each of the first bracket arm and the second bracket arm includes an intermediate arm portion extending between the proximal arm portion and the distal arm portion, and the arm height of the intermediate arm portion is approximately equal to the height of the substrate, so that light emitted parallel to the first surface and the second surface illuminates the corresponding top reflector segment and the bottom reflector segment with sufficient intensity to enable the headlight system to form a headlight beam with substantially uniform light intensity.

15. The bracket according to claim 10, wherein the first LED group and the second LED group are respectively placed at positions on the first surface and the second surface close to positions corresponding to filaments in the halogen lamp.

16. The bracket of claim 10, wherein at least a portion of the LEDs comprising the first LED group and the second LED group are configured to emit light laterally substantially parallel to a lateral axis of the first surface and the second surface.

17. A projector headlight system, comprising: a reflector comprising a top reflector, a bottom reflector, a first side reflector, and a second side reflector; a lens optically aligned with the reflector and configured to form a headlight beam to illuminate an area in front of the vehicle; An LED retrofit lamp coupled to a reflector, comprising: a substrate comprising a first surface spaced a distance from a second surface to define a longitudinal substrate side and a lateral substrate side, the distance defining a substrate height, a first LED group mounted on the first surface and a second LED group mounted on the second surface, and A support bracket configured to engage the longitudinal side of the substrate to mechanically support the substrate to align with the central optical axis of the reflector so that light emitted by the first LED group and the second LED group perpendicular to the first surface and the second surface illuminates the corresponding first side reflector segment and the second side reflector segment, and light emitted parallel to the first surface and the second surface illuminates the corresponding top reflector segment and the bottom reflector segment with sufficient intensity to enable the lens to form a headlight beam with substantially uniform light intensity.

18. The projector headlamp system of claim 17 , wherein the support bracket includes a first elongated bracket arm and a second elongated bracket arm, each bracket arm including a proximal arm portion having an inner surface providing a first longitudinally extending slot to engage a corresponding longitudinal side of the substrate between the first bracket arm and the second bracket arm to support a proximal end of the substrate, and each bracket arm further includes at least one arm portion having a width approximately equal to a width of the substrate to define an opening in each bracket arm, light emitted parallel to the first surface and the second surface can pass through the opening to illuminate the corresponding top reflector segment and bottom reflector segment.

19. The projector headlamp system of claim 17, wherein the first LED group and the second LED group comprise respective first LED packages and second LED packages, each LED package being configured to emit light at a maximum relative luminous intensity of substantially approximately 100% in a direction away from the substrate and parallel to a vertical axis of the chip, and to emit light at a maximum relative luminous intensity of substantially approximately 5% in a direction away from the sides of the first LED package and the second LED package and substantially parallel to a horizontal axis of the chip, so that light emitted at a small angle relative to the horizontal axis of the chip will pass through corresponding openings in corresponding sides of the bracket, thereby illuminating corresponding top and bottom reflectors with sufficient luminous intensity to enable the projector headlamp system to project a headlight beam having a substantially uniform luminous intensity.

20. The projector headlamp system of claim 19, wherein the first LED package and the second LED package are each coated with a blue phosphor material over at least a portion of a top light emitting surface and at least some portions of an edge of each chip, such that light emitted by the LEDs comprising each chip activates the phosphors to emit light at a small angle relative to a horizontal axis of each chip so as to illuminate the corresponding top and bottom reflectors with sufficient luminous intensity to enable the projector headlamp system to project a headlight beam with substantially uniform luminous intensity.

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