Light function control redundancy when changing light intensity of a pixelated vehicle headlamp

Abstract

Embodiments of the present disclosure relate to changing light function control redundancy when pixelating vehicle headlamp light intensity. A vehicle headlamp control circuit can be configured to control a vehicle headlamp comprising a plurality of lighting elements. The vehicle headlamp control circuit can comprise a first communication interface configured to receive a first signal comprising a first set of values for driving the plurality of lighting elements, and a second communication interface configured to receive a second signal comprising an intensity threshold. The circuit can be configured to determine a composite intensity associated with the first set of values, and to drive the plurality of lighting elements using the first set of values if the composite intensity associated with the first set of values satisfies the intensity threshold.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to circuits for driving and controlling a pixelated light source, for example, for a vehicle headlamp including an array of light emitting diodes (LEDs) or other light source including a plurality of individually controllable lighting elements. BACKGROUND

[0002] Drivers are commonly used to control the voltage, current, or power to a load. For example, a light emitting diode (LED) driver can control the power provided to a group of light emitting diodes. Some drivers can include a DC-to-DC power converter (e.g., buck-boost, buck, boost) or another DC-to-DC converter. These or other types of DC-to-DC power converters can be used to control and possibly vary the power at the load based on load characteristics. DC-to-DC power converters can be particularly useful for LED drivers to regulate the current flowing through a string of LEDs.

[0003] Some LED circuits include a large number of individually controllable LEDs arranged in a two-dimensional array. The individually controllable LEDs can be driven to provide different lighting for different driving conditions (e.g., high beam or low beam lighting), or to provide advanced lighting effects. For example, an advanced vehicle headlamp system is one example application of such LED circuits, whereby lighting effects related to vehicle operation can be used to improve the driving experience and increase vehicle safety. SUMMARY

[0004] In general, the present disclosure relates to circuits for controlling and driving a pixelated light source for an advanced vehicle headlamp system, for example, an array of light emitting diodes (LEDs), an array of digital micromirror devices (DMDs), a combination of LEDs and DMDs, or other types of individually controllable lighting elements. The circuits can be used to control the lighting elements to control changes from low beam lighting to high beam lighting, or to control changes from low beam to any other mode that implements advanced lighting effects. According to the present disclosure, changes in the lighting of the pixelated light source (e.g., from low beam mode to a different mode) can include a redundancy check to ensure that the output intensity of the light does not exceed an intensity threshold.

[0005] Circuits and techniques can be used for changes from low beam mode (or other safe lighting mode) to any other lighting mode that defines a higher light intensity. The described techniques can help ensure that high light output is avoided in the event that there can be errors in the data used to drive the LEDs. In this way, it can be avoided that a high beam mode or other lighting mode with higher intensity than the low beam mode is changed from the low beam mode (or other safe lighting mode) by accident, thereby improving safety and avoiding unwanted glare for oncoming traffic. The redundant check can add an additional level of safety for the headlamp changes, which can be useful for vehicle headlamp operation. In other examples, the techniques of the present disclosure can also be used for changes from a high light output mode to a low light output mode, in which case the expected light intensity can be checked to confirm that it is below an intensity threshold

[0006] In one example, a vehicle headlamp control circuit can be configured to control a vehicle headlamp comprising a plurality of lighting elements. The vehicle headlamp control circuit can comprise a first communication interface configured to receive a first signal comprising a first set of values for driving the plurality of lighting elements, and a second communication interface configured to receive a second signal comprising an intensity threshold. The vehicle headlamp control circuit can be configured to determine a composite intensity associated with the first set of values, and to drive the plurality of lighting elements using the first set of values if the composite intensity associated with the first set of values satisfies the intensity threshold. In some examples, the composite intensity satisfies the intensity threshold when the composite intensity is greater than the threshold. In other examples, the composite intensity satisfies the intensity threshold when the composite intensity is less than the threshold. Thus, the vehicle headlamp control circuit can be configured to control changes from a low intensity light output (e.g., a low beam lighting mode) to a high intensity light output (e.g., a high beam lighting mode), and vice versa. In addition, the vehicle headlamp control circuit can also control other types of lighting changes or effects, as described in more detail below.

[0007] In another example, the present disclosure describes a method of controlling a vehicle headlamp. The method can comprise receiving a first signal comprising a first set of values for driving a plurality of lighting elements of a vehicle headlamp; receiving a second signal comprising an intensity threshold; determining a composite intensity associated with the first set of values; and driving the plurality of lighting elements using the first set of values if the composite intensity associated with the first set of values satisfies the intensity threshold.

[0008] In another example, the disclosure describes a headlamp unit for a vehicle, the headlamp unit including a plurality of lighting elements and a vehicle headlamp control circuit configured to control the plurality of lighting elements. The vehicle headlamp control circuit can include a first communication interface configured to receive a first signal including a first set of values for driving the plurality of lighting elements and a second communication interface configured to receive a second signal including an intensity threshold. The vehicle headlamp control circuit can be configured to determine a composite intensity associated with the first set of values, drive the plurality of lighting elements using the first set of values if the composite intensity associated with the first set of values satisfies the intensity threshold, and drive the plurality of LEDs using a second set of values if the composite intensity associated with the first set of values does not satisfy the intensity threshold.

[0009] The details of these and other examples are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings, and from the claims. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 is a block diagram illustrating a pixel light source including a control circuit that is controlled based on two different inputs.

[0011] Figure 2 is a conceptual diagram of a right side vehicle headlamp including an array of light emitting diodes (LEDs), showing a low beam setting with only some LEDs active and a high beam setting with all LEDs active.

[0012] Figures 3A-3F is a conceptual diagram of left and right side vehicle headlamps in some example lighting modes, where different groups of LEDs are active.

[0013] Figure 4 is a timing diagram showing transmission of a picture (i.e., bitmap) to an LED circuit, where a high beam picture is transmitted in error.

[0014] Figure 5 is a block diagram of an example system for an advanced vehicle headlamp.

[0015] Figure 6 and 7 is a flowchart consistent with the techniques in accordance with the present disclosure. DETAILED DESCRIPTION

[0016] The present disclosure relates to circuits that can be used in advanced vehicle headlamp systems. The circuits can be used to control and drive lighting elements, such as light emitting diodes (LEDs), digital micromirror devices (DMDs), combinations of LEDs and DMDs, or other types of lighting elements that are independently controllable. In particular, the circuits can provide control redundancy when changing lighting modes, such as when changing from a low beam lighting mode to a high beam lighting mode, or vice versa. In addition, the circuits can also be used to control changes from a normal lighting mode (e.g., low beam or high beam) to an advanced lighting mode (e.g., with advanced lighting effects), or vice versa. The control redundancy can improve vehicle safety and help reduce or eliminate unwanted or undesirable changes in lighting modes.

[0017] For example, the circuits can control and drive the lighting elements to implement lighting mode changes, such as to implement an increase in brightness from low beam to high beam, to implement a decrease in brightness from high beam to low beam, to shape light output to implement a reduction in glare perceived by operators of other vehicles, to enhance illumination of one or more objects, to adjust or project visual aids or guide elements to help a vehicle operator, to project one or more symbols, to project a guide line for a vehicle operator, to shape light projected by LEDs, to increase light intensity of a portion of light projected by LEDs, or to implement other effects.

[0018] Lighting adjustments according to the present disclosure can include adjustments from a low beam mode to a high beam mode (or vice versa) based on user controls, or the adjustments can be more advanced and can be performed based on road information, road hazard information, road images, and / or navigation information collected or presented by the vehicle. For example, the lighting adjustments can be based on object detection, or based on other factors. In some cases, the vehicle can be equipped with cameras that can capture real-time video that can be processed in real-time to perform such object detection and adaptive lighting control.

[0019] According to the present disclosure, making any changes in illumination in a headlamp lighting (e.g., from a low beam mode to a different mode) by a pixelated light source can include a redundancy check to ensure that the output intensity of light does not exceed an intensity threshold. In some examples, circuits and techniques can be used to go from a low beam mode (or another safe lighting mode) to any other mode of illumination that defines a higher light intensity than the low beam mode, such as a high beam mode, an advanced illumination mode, an object illumination mode, a road line illumination mode, or any other mode in which the LEDs are illuminated to a higher light intensity than the low beam mode.

[0020] The described techniques can help ensure that high light output is avoided in the event that errors can exist in the data used to drive the LEDs. In this way, an unexpected switch from a low beam mode (or other safety lighting mode) to a high beam mode or other lighting mode having a higher intensity than the low beam mode can be avoided, thereby improving safety and avoiding undesirable glare to oncoming traffic. The redundant check can add an additional level of safety to the headlamp changes, which can be useful for vehicle headlamp operation. Likewise, in other examples, the techniques of the present disclosure can also be used for changes from a high light output mode to a low light output mode, in which case the expected light intensity can be checked to confirm that it is below an intensity threshold.

[0021] Figure 1 is a block diagram illustrating a pixel light source 14, including a vehicle headlamp control circuit 100 that controls the pixel light source based on two different inputs. The pixel light source 14 can include an array of illumination elements 102, such as individually controllable LEDs, individually controllable DMDs, a combination of LEDs and DMDs, or other types of individually controllable illumination elements. For example, the illumination elements can include a plurality of individually controllable LEDs arranged in a two-dimensional array to define a vehicle headlamp, a plurality of individually controllable illumination elements that include micro-mirrors arranged in a two-dimensional array to define a vehicle headlamp, or a combination thereof.

[0022] The vehicle headlamp control circuit 100 can include two or more different interfaces that are configured to receive signals for controlling the illumination elements 102. In particular, a first communication interface 105 can be configured to receive a first signal that includes a first set of values for driving the illumination elements 102. The first communication interface 105 can include a video interface that is configured to receive a video frame or picture, which can include a bitmap of intensity values for a plurality of different illumination elements 102. The bitmap can be generated by a video signal source 10, which can include a processor such as a central processing unit (CPU), a graphics processing unit (GPU), or other processor.

[0023] In some cases, the one or more bitmaps received via the first communication interface 105 can have errors or incorrect data. Accordingly, to account for possible errors in the bitmap data and to avoid unintended changes to the light output of the lighting elements 102, the vehicle headlamp control circuit 100 can be configured to provide control redundancy when changing lighting modes, such as when changing from a low beam lighting mode to a high beam lighting mode, or vice versa. In particular, the vehicle headlamp control circuit 100 can include a second communication interface 106 configured to receive a second signal including an intensity threshold. The intensity threshold can be delivered through a separate control interface (e.g., separate from the video interface used to deliver the bitmaps to the control circuit 100). The intensity threshold can define a total current, a duty cycle, a brightness level, or other value indicative of light output intensity. The intensity threshold can be sent to the control circuit 100 from a control source 12, which can include a microcontroller. Although the video signal source 10 and the control source 12 are shown as separate components, in some examples the video signal source 10 and the control source 12 can also be implemented as separate software routines on the same processor. Accordingly, the source 12 can include a controller separate from the video signal source 10, or can use one common processor to implement both the video signal source 10 and the control source 12 as separate software algorithms that deliver two different signals to the vehicle headlamp control circuit 100.

[0024] The vehicle headlamp control circuit 100 can be configured to determine a composite intensity associated with the first set of values received via the first communication interface 105 (e.g., a composite intensity associated with the bitmaps) and to drive the plurality of lighting elements 102 using the first set of values if the composite intensity associated with the first set of values satisfies the intensity threshold received through the second communication interface 106. In this way, control redundancy can be implemented to help avoid unwanted or undesirable changes in the light output of the lighting elements. To control changes from a lower light output mode to a higher light output mode, for example, the vehicle headlamp control circuit 100 can be configured to drive the plurality of lighting elements 102 using the first set of values if the composite intensity value associated with the first set of values is greater than the intensity threshold. Alternatively, to control changes from a higher light output mode to a lower light output mode, the vehicle headlamp control circuit 100 can be configured to drive the plurality of lighting elements 102 using the first set of values if the composite intensity associated with the first set of values is less than the intensity threshold. Accordingly, the phrase“satisfies the intensity threshold” can refer to either of the cases where the composite intensity is greater than the intensity threshold, or alternatively the composite intensity is less than the intensity threshold

[0025] The vehicle headlamp control circuit 100 can also be coupled to a memory 18 that can store one or more fail-safe images or bitmaps. The memory 18 can be part of the vehicle headlamp control circuit 100 or can comprise a separate component that is connected to the vehicle headlamp control circuit 100 via a memory interface 107 that can be connected to the memory 18 via a communication bus. The fail-safe images stored in the memory 18 can include one or more default images or one or more previously used images that are used to drive the lighting elements 102 without causing any lighting changes or effects.

[0026] In some examples, the vehicle headlamp control circuit 100 can be configured to use the first set of values received via the first communication interface 105 to drive the plurality of lighting elements if the composite intensity associated with the first set of values is below an intensity threshold received through the second communication interface 106, and to use a second set of values to drive the plurality of lighting elements 102 if the composite intensity associated with the first set of values is above the intensity threshold. In this example, the first set of values can be configured to change the plurality of lighting elements from a low beam lighting mode to a high beam lighting mode, but this change can only occur if the composite intensity associated with the first set of values is below the intensity threshold received through the second communication interface 106. If the composite intensity associated with the first set of values is above the intensity threshold, then the second set of values can be used, and the second set of values can include, for example, a set of previously used values that were previously used to drive the plurality of lighting elements, or the second set of values includes a set of default values stored in the memory 18.

[0027] In other examples, the vehicle headlamp control circuit 100 can be configured to use the first set of values received via the first communication interface 105 to drive the plurality of lighting elements if the composite intensity associated with the first set of values is above an intensity threshold received through the second communication interface 106, and to use a second set of values to drive the plurality of lighting elements if the composite intensity associated with the first set of values is below the intensity threshold. In this example, the first set of values can be configured to change the plurality of lighting elements from a high beam lighting mode to a low beam lighting mode, but this change can only occur if the composite intensity associated with the first set of values is below the intensity threshold received through the second communication interface 106. Again, the techniques of the present disclosure can be useful whenever a lighting change is made, such as to implement an increase in brightness from low beam to high beam, to implement a decrease in brightness from high beam to low beam, to shape the light output to implement a reduction in glare perceived by operators of other vehicles, to enhance illumination of one or more objects, to adjust or project a visual aid or guide element to assist a vehicle operator, to project one or more symbols, to project a guide line for a vehicle operator, to shape light projected by the lighting elements 102, to increase the light intensity of a portion of light projected by the lighting elements 102, or to implement other effects.

[0028] In addition to providing control redundancy, the intensity threshold received via the second communication interface 106 can also be used for additional purposes, such as checking whether the actual current used to drive the lighting element 102 after a lighting change is consistent with the expected current. For example, when changing from a lower light output mode to a higher output mode, in response to driving multiple lighting elements using a first set of values, the vehicle headlight control 100 can be further configured to: measure the actual current used to drive the multiple lighting elements 102 using the first set of values, and if the actual current used to drive the multiple lighting elements using the first set of values ​​is higher than the intensity threshold, generate an alarm or change operation to drive the multiple lighting elements using a second set of values. Of course, if the actual current used to drive the multiple lighting elements using the first set of values ​​is lower than the intensity threshold for the case of changing from a higher light output mode to a lower light output mode, such a measurement can also be used to generate an alarm or change operation.

[0029] Furthermore, in some examples, additional thresholds can be used and checked. For example, when the first set of values ​​is configured to change multiple lighting elements 102 from low beam to high beam mode, additional thresholds can be checked to ensure that the expected high beam mode is sufficiently bright. In this case, the intensity thresholds received via the second communication interface 106 may include a first intensity threshold, and the circuit 100 may be further configured to generate an alarm in response to a composite intensity associated with the first set of values ​​falling below a second intensity threshold. For example, the alarm may be sent from the vehicle headlight control circuit 100 to the control source 12 to identify a potential problem with the high beam output.

[0030] In different examples, the intensity threshold can define the total current, duty cycle, luminance level, or another threshold indicating the light output intensity. Where the intensity threshold includes a current threshold, for example, the composite intensity can be defined by the combined amount of current associated with driving multiple illumination elements 102 at a first set of values. In other cases where the intensity threshold is defined based on duty cycle or luminance level, the composite intensity can be defined similarly to the threshold to provide a useful comparison.

[0031] The first communication interface 105 can be configured to receive a first signal on a frame-by-frame basis according to a video protocol. The second communication interface 106 can be configured to receive a second signal in response to a desired change in a plurality of lighting elements from a first lighting mode to a second lighting mode. This desired change can be user-controlled, in which case the second signal can be sent in response to user input. In other examples, the desired change can be automatically controlled and based on images detected by an onboard camera, changes in vehicle operation, or other factors such as vehicle turning (where edge lighting can be enhanced) or a user-selected signal (e.g., a user-selected turn signal).

[0032] In some examples, a single threshold value can be defined for the entire set of lighting elements 102. In such cases, the first set of values can include a bitmap for driving all of the lighting elements 102. In other examples, multiple different threshold values can define multiple thresholds for different portions or subsets of the lighting elements 102. When multiple thresholds are defined for different portions of the lighting elements 102, the circuit 100 can perform more advanced checks. For example, the vehicle headlamp control 100 can check the brightness of a portion or subset of the lighting elements 102 (e.g., a center portion, a particular number of rows / columns / quadrants, a top and bottom, or other defined portions) that has multiple independently adjustable or controllable thresholds. In some examples, the threshold value can be used to check whether pixels above or outside of a defined cutoff line are activated. For example, lights above or outside of a defined cutoff line can be associated with a particular lighting mode, such as high beams, edge lighting for a turn, an object detection mode, and / or lighting for presenting or illuminating a navigation line or symbol.

[0033] In examples where a threshold is associated with a portion of the lighting elements 102, the portion can include a first portion, the intensity threshold can include a first intensity threshold, and the composite intensity can include a first composite intensity. In such cases, the first communication interface 105 can also be configured to receive a third signal including a second set of values for driving a second portion of the lighting elements associated with the lighting elements 102, and the second communication interface can further be configured to receive a fourth signal including a second intensity threshold. The vehicle headlamp control circuit 100 can be configured to determine a second composite intensity associated with the second set of values, and if the second composite intensity associated with the second set of values satisfies the second intensity threshold, then drive the second portion of the lighting elements associated with the lighting elements 102 using the second set of values.

[0034] Figure 2 is a conceptual diagram of a right side vehicle headlamp 20 that includes an array of individually controllable LEDs. By activating different groups of LEDs, different types of lighting can be achieved. For example, in a low beam lighting mode, the right side vehicle headlamp 20 can be controlled to activate a subset 21 of the LEDs of the vehicle headlamp. Optionally, in a high beam lighting mode, all of the LEDs can be activated (i.e., subset 21 and subset 22). Thus, when changing from a low beam mode to a high beam mode, subset 22 can be activated, which can result in an increase in the total current used by the vehicle headlamp 20. By using intensity thresholds and comparing them to the expected composite intensity associated with an image (bitmap) for driving the headlamp 20, safety can be enhanced and unwanted or undesirable lighting changes can be reduced or avoided.

[0035] Figures 3A-3Fis a conceptual diagram of left and right vehicle headlamps in some example illumination modes, where different groups of LEDs are active. Again, the techniques of the present disclosure can be used to monitor and control illumination mode changes, such as changes to Figures 3A-3F different illumination modes shown and changes from that mode.

[0036] Figure 3A An example low beam illumination mode is shown, where left vehicle headlamp 30A illuminates subset 301A and not subset 302A. Similarly, in this example low beam illumination mode, right vehicle headlamp 30B illuminates subset 301B and not subset 302B.

[0037] Figure 3B An example high beam illumination mode is shown, where left vehicle headlamp 31A illuminates the entire LED group 305A. Similarly, in the example high beam illumination mode, right vehicle headlamp 31B illuminates the entire LED group 305B. Figure 3B

[0038] Figure 3C is another possible illumination mode, where left vehicle headlamp 32A illuminates a first subset of LEDs 306A similar to a low beam illumination mode, and further illuminates a second subset of LEDs 307A to provide or illuminate one or more guide lines. Similarly, in this example guide illumination mode, right vehicle headlamp 32B illuminates a first subset 306B similar to a low beam illumination mode, and further illuminates a second subset of LEDs 307B to provide or illuminate one or more guide lines.

[0039] Figure 3D Another possible illumination mode is shown, where left vehicle headlamp 33A illuminates a first subset of LEDs 308A similar to a low beam illumination mode. Figure 3D The example illumination mode shown can include illumination of one or more symbols (e.g., a turn arrow). In this example, right vehicle headlamp 33B illuminates a first subset 308B similar to a low beam illumination mode, and further illuminates a second subset of LEDs 309 to provide or illuminate the symbol.

[0040] Figure 3E is another possible illumination mode, where left vehicle headlamp 34A illuminates a first subset of LEDs 310A similar to a low beam illumination mode. Figure 3E The example illumination mode shown in can include illumination of one or more objects or road hazards, such as in response to object detection. In this example similar to a low beam illumination mode, right vehicle headlamp 34B illuminates a first subset 310B, and further illuminates a second subset of LEDs 312 to illuminate the object or road hazard (possibly in response to object detection based on a vehicle-mounted camera system). ​

[0041] Figure 3F Another possible lighting mode (e.g., a safety lighting mode with an intensity lower than low beam) is provided, in which a small subset of LEDs 311A ​​and 311B are illuminated by the left vehicle headlight 36A and the right vehicle headlight 36B.

[0042] Figures 3A-3F This is merely an example of various lighting patterns that can be achieved using pixelated light sources. The techniques disclosed herein can... Figures 3A-3F This is used when changing between the modes shown. However, other types of lighting modes can also be defined and used, such as modes that provide edge lighting during cornering, display other types of symbols, adaptive and changing modes based on object detection, or other modes. The techniques disclosed herein are useful whenever a lighting change occurs in pixelated vehicle headlights.

[0043] The intensity threshold or multiple thresholds can be defined or adjusted according to the mode or use case. This can be accomplished, for example, by register settings or mode changes transmitted via control signals to the second communication interface 106. Although the current threshold is described in detail in this disclosure, according to embodiments, the threshold can be set to a duty cycle, current level, brightness level, or anything indicating the LED brightness associated with the vehicle headlights. The threshold can be set independently or synchronized with video frames.

[0044] Figure 4 Timing diagram 40 illustrates the transmission of an image (i.e., a bitmap) to an LED circuit (or another pixelated light source), where the high beam image is incorrectly transmitted. In timing diagram 40, multiple low beam images are sent and then replaced by a single high beam image (i.e., Figure 4 The image shown in image #3 is interrupted. Figure 4 In the example, during the low-beam mode associated with images 0-5, the current threshold can be defined as 1.5 amps. Since image #3 will define a composite current greater than the threshold of 1.5 amps, the LED control circuit can ignore or discard image #3, and the LED control circuit can drive the LED using the default image or another version of image #2.

[0045] according to Figure 4The timing diagram of FIG. 6B shows that, in order to activate a lighting mode change from low beam to high beam, an intensity threshold change is needed. For example, the intensity threshold limit for high beam can be increased from 1.5 amps to 8 amps, which can occur before receiving picture #6. Pictures #6 and #7 can cause a change from low beam mode to high beam mode, which can be confirmed by checking whether the composite current associated with picture #6 and picture #7 is below the current threshold. Since the current threshold was increased from 1.5 amps to 8 amps before receiving picture #6 and #7, this change to high beam mode is allowed, and the LED control circuit can use pictures #6 and #7 to drive the LEDs.

[0046] Furthermore, according to the timing diagram of FIG. 6B, for a lighting mode change from high beam back to low beam, the intensity threshold can again be changed back to 1.5 amps before receiving picture #8. The LED control circuit can use picture #8 to drive the LEDs, since the composite intensity associated with picture #8 is less than 1.5 amps, satisfying the low beam threshold. Figure 4

[0047] Figure 5 is a block diagram of an example system for an advanced vehicle headlamp. In particular, Figure 5 An adaptive vehicle lighting system 50 is shown, which includes one or more camera sensors 502 configured to capture video data associated with a scene illuminated by the vehicle lighting system, a graphics processing unit (GPU) 504 to process the video data, and a vehicle headlamp unit 506 including a set of LEDs 508 that can be arranged in a two-dimensional array, and a vehicle headlamp control circuit 510 configured to control the LEDs 508. The vehicle headlamp control circuit 510 can include separate circuitry with respect to the LEDs 508, or alternatively, these components can be combined into a common circuit to define a fully integrated vehicle headlamp unit 506 formed in a common silicon structure.

[0048] The vehicle headlamp control circuit 510 can include an LED controller 512 configured to receive the processed video data from the GPU via a first interface 518, which can include a high-speed video interface, or a differential interface commonly used in automotive circuit applications. Furthermore, according to the present disclosure, the LED controller 512 can also be configured to receive an intensity threshold from a control unit 505 via a control interface 517. The LED controller 512 can be configured to determine a composite intensity associated with an image of the video data, and cause an LED driver 514 to use the image of the video data to drive the LEDs 508 if the composite intensity associated with the first set of values satisfies the intensity threshold.

[0049] ​The LED driver 514 can include a direct-current-direct-current converter or other power device configured to drive the LEDs based at least in part on the processed video data. In some cases, the LED driver 514 can include one or more direct-current-direct-current power converters that utilize parallel sets of linear current sources to deliver precise amounts of current to a load for different modes. In such examples, the LED driver 514 can use additional linear current sources as the current demand increases.

[0050] The GPU 504 can process the raw video data and generate processed video data that is processed to achieve a desired lighting effect through the LEDs. For example, such processing by the GPU 504 can be based on navigation information collected or presented by the vehicle, based on object detection, or based on other factors. For example, the camera sensor 502 can deliver real-time video in a raw format to the GPU 504, and the GPU can process the raw video to identify scenes, roads, features, obstacles, or other elements within the raw video data. In some examples, the GPU can perform one or more object detection algorithms on the raw video data in order to identify objects or elements within the video data captured by the camera sensor 502. Based on such object detection algorithms, the GPU 504 can modify the raw video data to generate processed video data, and can modify the processed video data relative to the raw video data in a manner that can achieve a desired lighting effect through the LEDs 508.

[0051] For example, object detection can be used to identify oncoming traffic, road hazards, or obstacles. Such object detection can be used to modify the raw video data such that the processed video data has pixelated data adjustments relative to the raw video data. The pixelated data adjustments can adjust the raw video data where objects are detected in the field of view. In this way, the processed data itself can be altered in a manner that helps achieve a lighting effect of the LEDs 508, such as reducing glare perceived by operators of other vehicles, illumination of one or more objects, presenting visual aids or guidance to help vehicle operators, projecting one or more symbols, projecting a guidance line for a vehicle operator, shaping a light beam, reducing light intensity, presenting a symbol, shape, or symbol, or presenting other effects. Other desirable lighting effects can also include illumination of a logo or symbol, such as to present welcome information or lighting effects to a driver when the vehicle is starting or when the vehicle is in a park mode.

[0052] Referring again to object detection, the GPU 504 can process the raw video data and identify oncoming traffic in the raw video data. In this case, such objects can be used to cause a particular pixelated intensity decrease such that the LEDs 508 implement a glare reduction for the oncoming traffic. As another example, the GPU 504 can process the raw video data to identify an object or a road hazard, such as an animal on the road, and in this case, the object can be used to cause a particular pixelated intensity increase such that the LEDs 508 illuminate the object with more light. The raw video data can include a bitmap of RGB intensity values, and the processed video data can include a similar bitmap of RGB intensity values that includes intensity adjustments to those pixels associated with object detection.

[0053] Although RGB intensity values are discussed herein with respect to video data, other video data formats can be such as well, such as formats that use chrominance and luminance values, LUV formats, CMYK formats, vectorized video data formats, or other video data formats. The bitmap of intensity values can be viewed as a bitmap of a video image, or as a bitmap of intensity values for individual pixels of an LED array. Thus, by processing a bitmap of an image, the GPU can essentially define a new bitmap of that image that, when used to drive the LEDs 508, is modified to implement object detection, reduce glare, or other effects.

[0054] As noted above, the first interface 518 can include a high-speed video interface, or a differential interface commonly used in automotive circuit applications. Examples of the first interface 518 can include an Ethernet interface; a Gigabit Multimedia Serial Link (GMSL) interface; a Controller Area Network (CAN) bus interface; a Controller Area Network Flexible Data (CAN-FD) bus interface; an interface defined according to the FlexRay protocol; a link defined according to the Low Voltage Differential Signaling (LVDS) standard, such as FPD-Link, FlatLink, FPD-Link II, FPD-Link III, and OpenLDI; or a Controller Area Network eXtended (CAN-XL) bus interface.

[0055] Unlike the first interface 518, which transmits video data to the vehicle headlamp unit 506, the second interface 517 can comprise a control signal interface. The second interface 517 can be used to transmit intensity threshold values from the control unit 505 to the LED controller 512. The second interface 517 can also control one or more other functions of the vehicle headlamp, as well as perform or facilitate diagnostics. For applications where safety is not important, this second interface 517 can be easily disabled (either by actually disabling its functionality or by simply setting the threshold value to a value that will be satisfied by any type of image that will be used to drive the LEDs 508). In other examples, the control interface 517 used to send intensity threshold values can also come directly from the GPU 504 as a separate communication interface from the GPU 504 to the LED controller 512 (i.e., separate from the first interface 518).

[0056] In any case, in accordance with the present disclosure, the LED controller 512 can be configured to determine a composite intensity associated with an image of the video data and cause the LED driver 514 to drive the LEDs 508 using the image of the video data if the composite intensity associated with the first set of values satisfies an intensity threshold. If not, the LED controller 512 can cause the LED driver 514 to drive the LEDs 508 using alternative data, such as a “safe” video frame used previously or a default “safe” video frame saved in memory (not shown) in the LED controller 512. Figure 5

[0057] In addition to object detection or other processing that can be performed by the GPU 504, in some examples, additional video data adjustments can be made, such as so-called gamma correction of the video data. In some examples, the gamma correction is performed by the GPU 504 after the initial processing of the video data described above. In some examples, the gamma correction is performed by the LED controller 512 after the GPU 504 processes the video data described above. In other examples, the LED driver 514 can be configured to perform the gamma correction. The gamma correction or other video data adjustments can be used to further improve the illumination achieved by the LEDs 508. The processed and adjusted video data (e.g., data processed by the GPU 504 and then adjusted with gamma correction) can still comprise a bitmap of RGB intensity values (or other format) that includes intensity adjustments to pixels associated with object detection, intensity adjustments to pixels used to render guide lines or guide features, and gamma correction adjustments. The LED driver 514 can then use the processed and adjusted video data (e.g., bitmap) to drive the LEDs 508, which can comprise an array of LEDs with pixels corresponding to the intensity values defined in the video data bitmap. In accordance with the present disclosure, such an image or bitmap of RGB intensity values can only be used if the composite intensity associated with those values satisfies a threshold value set by the control unit 505 and transmitted via the second interface 517.​

[0058] The use of intensity thresholds according to this disclosure can provide an additional level of safety for vehicle headlight operation, ensuring that only permitted light patterns can be displayed without adding excessive complexity to the light source driver. When the light source controller receives image information through a first interface and a threshold through a second interface, a check can be performed by the light source controller. The check can be performed by calculating a composite luminance associated with the received image. This composite luminance can then be compared to an adjustable threshold, which is transmitted to the light source controller via an interface separate from the one used to transmit the image. If the image is too bright, it can be ignored and the device can continue to drive the lighting element using the last valid image or use a defined fail-safe image. Similarly, the luminance check can be refined to check the luminance of a complete array of pixelated lighting elements with a single threshold, the luminance of an array sub-section (e.g., center section, number of rows / columns / quadrants) with several independently adjustable thresholds, or to check whether pixels above, below, or beyond a defined cutoff line are activated at specific locations in the array.

[0059] Figure 6 and 7 This is a flowchart consistent with the technology according to this disclosure. It will be... Figure 1 Description of the 100° angle of the vehicle headlight control circuit Figure 6 Although other circuits can be used to perform these techniques. For example... Figure 6 As shown, the vehicle headlight control circuit 100 receives an intensity threshold (601) via a control interface. Furthermore, the vehicle headlight control circuit 100 receives a bitmap for driving the lighting element 102 via a video interface (602). Specifically, the vehicle headlight control circuit 100 receives the bitmap at a first communication interface 105 of the control circuit 100 and the intensity threshold at a second communication interface 106 of the control circuit 100. The vehicle headlight control circuit 100 determines the total intensity associated with driving the lighting element using the bitmap and determines whether the intensity of the bitmap-based lighting element meets the intensity threshold (603). If the intensity of the bitmap-based lighting element meets the threshold (the "yes" branch of 603), the vehicle headlight control circuit 100 drives the lighting element 102 using the bitmap (604). However, if the intensity of the bitmap-based lighting element does not meet the threshold (the "no" branch of 603), the vehicle headlight control circuit 100 drives the lighting element 102 using alternative data (605). For example, alternative data may include previously used bitmaps (i.e., previously received video data frames used to drive lighting elements) or default and secure bitmaps stored in memory 18.

[0060] From Figure 5 Angle description of the adaptive vehicle lighting system 50 shown. Figure 7. According to Figure 5 , while similar techniques can be used for other systems, such as systems of other types of vehicle headlamps having individually controllable lighting elements. Referring to Figure 7 , the camera sensor 502 of the adaptive vehicle lighting system 50 captures video data associated with the driving vehicle (701). The GPU 504 can process the video data to create a bitmap having adjustments or effects (702). For example, the GPU 504 can use the captured video data associated with the road or road conditions in order to add adjustments or effects to the bitmap used to drive the individually controllable LEDs 508. Again referring to Figures 3C-3E , for example, the object lighting of the guide lines 307A and 307B in the bitmap, one or more symbols 309 in the bitmap, or a particular subset of lighting elements 312 at a particular location in the bitmap can be added by the GPU in order to define such lighting features, adjustments, or effects in the bitmap. The lighting features, adjustments, or effects can be based on the captured images of the road conditions, and these features, adjustments, or effects can include LEDs that are additionally activated beyond those shown in the low beam setting shown in Figure 3A .

[0061] The control unit 505 (or possibly the GPU 504) transmits the intensity threshold to the LED controller 512 via the control interface 517 (703). In addition, the GPU 504 transmits the bitmap having the lighting features, adjustments, or effects to the LED controller 512 via the video interface 516 (704). The LED controller 512 determines the total intensity associated with driving the LEDs 508 using the bitmap, and determines whether the intensity of the LEDs 508 based on the bitmap satisfies the intensity threshold (705). If the intensity of the LEDs 508 based on the bitmap satisfies the threshold (the “yes” branch of 705), then the LED controller 512 causes the LED driver 514 to drive the LEDs 508 using the bitmap (706). However, if the intensity of the LEDs 508 based on the bitmap does not satisfy the threshold (the “no” branch of 705), then the LED controller 512 causes the LED driver 514 to drive the LEDs 508 using alternative data (707). Again, for example, the alternative data can include a previously used bitmap (i.e., a previously received bitmap used to drive the lighting elements) or a default and safe bitmap stored in memory (not shown) associated with the vehicle headlamp control circuit 510.

[0062] The following examples can illustrate one or more aspects of the present disclosure.

[0063] Example 1 : A vehicle headlamp control circuit configured to control a vehicle headlamp comprising a plurality of lighting elements, the vehicle headlamp control circuit comprising: a first communication interface configured to receive a first signal comprising a first set of values for driving the plurality of lighting elements; and a second communication interface configured to receive a second signal comprising an intensity threshold, wherein the vehicle headlamp control circuit is configured to: determine a composite intensity associated with the first set of values, and if the composite intensity associated with the first set of values satisfies the intensity threshold, use the first set of values to drive the plurality of lighting elements.

[0064] Example 2: The vehicle headlamp control circuit of example 1, wherein the vehicle headlamp control circuit is configured to: if the composite intensity associated with the first set of values is below the intensity threshold, use the first set of values to drive the plurality of lighting elements, and if the composite intensity associated with the first set of values is above the intensity threshold, use a second set of values to drive the plurality of lighting elements.

[0065] Example 3: The vehicle headlamp control circuit of example 1 or 2, wherein the second set of values comprises a set of previously used values previously used to drive the plurality of lighting elements.

[0066] Example 4: The vehicle headlamp control circuit of example 1 or 2, wherein the second set of values comprises a set of default values.

[0067] Example 5: The vehicle headlamp control circuit of any of examples 1-4, wherein in response to using the first set of values to drive the plurality of lighting elements, the vehicle headlamp control circuit is further configured to: measure an actual amount of current used to drive the plurality of lighting elements using the first set of values; and if the actual amount of current used to drive the plurality of lighting elements using the first set of values is above the intensity threshold, generate an alert or change operation to drive the plurality of lighting elements using the second set of values.

[0068] Example 6: The vehicle headlamp control circuit of any of examples 1-5, wherein the intensity threshold is a first intensity threshold, and wherein the circuit is further configured to generate an alert in response to the composite intensity associated with the first set of values being below a second intensity threshold.

[0069] Example 7: The vehicle headlamp control circuit of any of examples 1 or 3-6, wherein the vehicle headlamp control circuit is configured to: if the composite intensity associated with the first set of values is above the intensity threshold, use the first set of values to drive the plurality of lighting elements, and if the composite intensity associated with the first set of values is below the intensity threshold, use a second set of values to drive the plurality of lighting elements.

[0070] Example 8: The vehicle headlamp control circuit of any of examples 1-6, wherein the first set of values is configured to change the plurality of lighting elements from a low beam lighting mode to a high beam lighting mode.

[0071] Example 9: The vehicle headlamp control circuit of any of examples 1-6 or 8, wherein the first set of values is configured to change the plurality of lighting elements from a lower intensity lighting mode to a higher intensity lighting mode.

[0072] Example 10: The vehicle headlamp control circuit of any of examples 1 or 3-6, wherein the first set of values is configured to change the plurality of lighting elements from a higher intensity lighting mode to a lower intensity lighting mode.

[0073] Example 11 : The vehicle headlamp control circuit of any of examples 1-10, wherein the intensity threshold comprises a current threshold.

[0074] Example 12: The vehicle headlamp control circuit of example 11, wherein the composite intensity is defined by a composite amount of current associated with driving the plurality of lighting elements with the first set of values.

[0075] Example 13: The vehicle headlamp control circuit of any of examples 1-12, wherein the first communication interface is configured to receive the first signal frame-by-frame according to a video protocol, and the second communication interface is configured to receive the second signal in response to a desired change of the plurality of lighting elements from a first lighting mode to a second lighting mode.

[0076] Example 14: The vehicle headlamp control circuit of any of examples 1-13, wherein the plurality of lighting elements comprises one or more of: a plurality of individually controllable light emitting diodes (LEDs) arranged in a two-dimensional array to define the vehicle headlamp; and a plurality of individually controllable lighting elements comprising micro-mirrors arranged in a two-dimensional array to define the vehicle headlamp.

[0077] Example 15: The vehicle headlamp control circuit of any of examples 1-14, wherein the first set of values comprises a bitmap for driving an array of lighting elements that define the vehicle headlamp.

[0078] Example 16: The vehicle headlamp control circuit of any of examples 1-14, wherein the first set of values comprises a bitmap for driving a portion of lighting elements associated with an array of lighting elements that define the vehicle headlamp.

[0079] Example 17: The vehicle headlamp control circuit of Example 16, wherein the portion comprises a first portion, the intensity threshold comprises a first intensity threshold, and the composite intensity comprises a first composite intensity, wherein: the first communication interface is further configured to receive a third signal comprising a second set of values for driving a second portion of the lighting elements associated with defining the array of lighting elements of the vehicle headlamp; the second communication interface is further configured to receive a fourth signal comprising a second intensity threshold; and the vehicle headlamp control circuit is further configured to: determine a second composite intensity associated with the second set of values, and if the second composite intensity associated with the second set of values satisfies the second intensity threshold, then drive the second portion of the lighting elements using the second set of values.

[0080] Example 18: A method of controlling a vehicle headlamp, comprising: receiving a first signal comprising a first set of values for driving a plurality of lighting elements of a vehicle headlamp; receiving a second signal comprising an intensity threshold; determining a composite intensity associated with the first set of values; and if the composite intensity associated with the first set of values satisfies the intensity threshold, then driving the plurality of lighting elements using the first set of values.

[0081] Example 19: The method of Example 18, further comprising if the composite intensity associated with the first set of values does not satisfy the intensity threshold, then driving the plurality of lighting elements using a second set of values.

[0082] Example 20: The method of Example 18 or 19, wherein the second set of values comprises one of: a set of previously used values previously used to drive the plurality of lighting elements; and a set of default values.

[0083] Example 21 : A headlamp unit for a vehicle, the headlamp unit comprising: a plurality of lighting elements; and a vehicle headlamp control circuit configured to control the plurality of lighting elements, the vehicle headlamp control circuit comprising: a first communication interface configured to receive a first signal comprising a first set of values for driving the plurality of lighting elements; and a second communication interface configured to receive a second signal comprising an intensity threshold, wherein the vehicle headlamp control circuit is configured to: determine a composite intensity associated with the first set of values, if the composite intensity associated with the first set of values satisfies the intensity threshold, then drive the plurality of lighting elements using the first set of values, and if the composite intensity associated with the first set of values does not satisfy the intensity threshold, then drive the plurality of LEDs using a second set of values.

[0084] Various aspects have been described in this disclosure.

Claims

1. A vehicle headlight control circuit configured to control a vehicle headlight comprising a plurality of lighting elements, the vehicle headlight control circuit comprising: The first communication interface is configured to receive a first signal including a first set of values ​​for driving the plurality of lighting elements; as well as The second communication interface is configured to receive a second signal, including an intensity threshold. The plurality of lighting elements are designed as pixelated light sources, and the intensity threshold indicates a threshold value for the light output intensity of the light source. The vehicle headlight control circuit is configured to: determine a composite intensity associated with the first set of values, and if the composite intensity associated with the first set of values ​​satisfies the intensity threshold, drive the plurality of lighting elements using the first set of values ​​to activate a first subset of the pixelated light sources; and if the composite intensity associated with the first set of values ​​does not satisfy the intensity threshold, drive the plurality of lighting elements using a second set of values ​​to activate a second subset of the pixelated light sources.

2. The vehicle headlight control circuit of claim 1, wherein the vehicle headlight control circuit is configured to: drive the plurality of lighting elements using the first set of values ​​if the composite intensity associated with the first set of values ​​is lower than the intensity threshold, and drive the plurality of lighting elements using a second set of values ​​if the composite intensity associated with the first set of values ​​is higher than the intensity threshold.

3. The vehicle headlight control circuit of claim 2, wherein the second set of values ​​includes a previously used set of values ​​previously used to drive the plurality of lighting elements.

4. The vehicle headlight control circuit according to claim 2, wherein the second set of values ​​includes a set of default values.

5. The vehicle headlight control circuit of claim 2, wherein in response to driving the plurality of lighting elements using a first set of values, the vehicle headlight control circuit is further configured to: Measure the actual current used to drive the plurality of lighting elements using the first set of values; and If the actual current used to drive the plurality of lighting elements using the first set of values ​​is higher than the intensity threshold, an alarm is generated or the operation is changed to drive the plurality of lighting elements using the second set of values.

6. The vehicle headlight control circuit of claim 2, wherein the intensity threshold is a first intensity threshold, and wherein the circuit is further configured to generate an alarm in response to the composite intensity associated with the first set of values ​​being lower than a second intensity threshold.

7. The vehicle headlight control circuit of claim 1, wherein the vehicle headlight control circuit is configured to: drive the plurality of lighting elements using the first set of values ​​if the composite intensity associated with the first set of values ​​is higher than the intensity threshold, and drive the plurality of lighting elements using a second set of values ​​if the composite intensity associated with the first set of values ​​is lower than the intensity threshold.

8. The vehicle headlight control circuit according to claim 1, wherein the first set of values ​​is configured to change the plurality of lighting elements from a low beam lighting mode to a high beam lighting mode.

9. The vehicle headlight control circuit of claim 1, wherein the first set of values ​​is configured to change the plurality of lighting elements from a lower intensity lighting mode to a higher intensity lighting mode.

10. The vehicle headlight control circuit of claim 1, wherein the first set of values ​​is configured to change the plurality of lighting elements from a higher intensity lighting mode to a lower intensity lighting mode.

11. The vehicle headlight control circuit according to claim 1, wherein the intensity threshold includes a current threshold.

12. The vehicle headlight control circuit of claim 11, wherein the composite intensity is defined by the composite amount of current associated with driving the plurality of lighting elements at the first set of values.

13. The vehicle headlight control circuit of claim 1, wherein the first communication interface is configured to receive the first signal frame by frame according to a video protocol, and the second communication interface is configured to receive the second signal in response to a desired change of the plurality of lighting elements from a first lighting mode to a second lighting mode.

14. The vehicle headlight control circuit according to claim 1, wherein the plurality of lighting elements comprises one or more of the following: Multiple individually controllable light-emitting diodes (LEDs) are arranged in a two-dimensional array to define the vehicle headlights; and Multiple individually controllable lighting elements, including micromirrors arranged in a two-dimensional array, define the vehicle headlights.

15. The vehicle headlight control circuit of claim 1, wherein the first set of values ​​includes a bitmap for driving an array of lighting elements defining the vehicle headlights.

16. The vehicle headlight control circuit of claim 1, wherein the first set of values ​​includes a bitmap for driving a portion of the lighting elements associated with the array of lighting elements defining the vehicle headlights.

17. The vehicle headlight control circuit of claim 16, wherein the portion includes a first portion, the intensity threshold includes a first intensity threshold, and the composite intensity includes a first composite intensity, wherein: The first communication interface is also configured to receive a third signal, the third signal including a second set of values ​​for driving a second portion of the lighting elements associated with an array of lighting elements defining the vehicle headlights; The second communication interface is also configured to receive a fourth signal including a second strength threshold; and The vehicle headlight control circuit is further configured to: determine a second composite intensity associated with the second set of values, and drive the second portion of the lighting element using the second set of values ​​if the second composite intensity associated with the second set of values ​​satisfies the second intensity threshold.

18. A method for controlling vehicle headlights, the method comprising: Receive a first signal including a first set of values ​​for a plurality of lighting elements for driving the vehicle headlights, wherein the plurality of lighting elements are designed as pixelated light sources, and an intensity threshold indicates a threshold of the light output intensity of the light source; Receive a second signal including an intensity threshold; Determine the composite strength associated with the first set of values; as well as If the composite intensity associated with the first set of values ​​satisfies the intensity threshold, the first set of values ​​is used to drive the plurality of lighting elements to activate a first subset of the pixelated light source; and if the composite intensity associated with the first set of values ​​does not satisfy the intensity threshold, the second set of values ​​is used to drive the plurality of lighting elements to activate a second subset of the pixelated light source.

19. The method of claim 18, further comprising driving the plurality of lighting elements using a second set of values ​​if the composite intensity associated with the first set of values ​​does not meet the intensity threshold.

20. The method of claim 19, wherein the second set of values ​​comprises one of the following: A previously used set of values ​​for driving the plurality of lighting elements; and A set of default values.

21. A headlight unit for a vehicle, the headlight unit comprising: Multiple lighting elements; as well as A vehicle headlight control circuit is configured to control the plurality of lighting elements, the vehicle headlight control circuit including: The first communication interface is configured to receive a first signal including a first set of values ​​for driving the plurality of lighting elements; as well as The second communication interface is configured to receive a second signal, including an intensity threshold. The plurality of lighting elements are designed as pixelated light sources, and the intensity threshold indicates a threshold value for the light output intensity of the light source. The vehicle headlight control circuit is configured to: determine a composite intensity associated with the first set of values; if the composite intensity associated with the first set of values ​​satisfies the intensity threshold, drive the plurality of lighting elements using the first set of values ​​to activate a first subset of the pixelated light sources; and if the composite intensity associated with the first set of values ​​does not satisfy the intensity threshold, drive the plurality of lighting elements using a second set of values ​​to activate a second subset of the pixelated light sources.

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