HEADLIGHT AND CONTROL METHOD FOR A HEADLIGHT

Abstract

A headlight for vehicles, having a light source unit for emitting light, an optical unit for deflecting the light in accordance with a predefined light distribution, and a control unit for generating a control signal, by means of which the light source unit and/or the optical unit can be controlled, wherein the control signal is generated depending on a number of environmental parameters, wherein an optimization program is stored in the control unit, by means of which optimization program the control signal is calculated from a plurality of individual control signals, wherein by means of the individual control signals different partial light distributions, each dependent on the environmental parameters, can be generated.

Claims

1. A headlight for vehicles, the headlight comprising: a light source unit adapted to emit light; an optical unit to deflect the light in accordance with a predefined light distribution; and a control unit to generate a control signal, via the control unit, the light source unit and/or the optical unit are adapted to be controlled, wherein the control signal is generated depending on at least one environmental parameter, wherein an optimization program is stored in the control unit, via which optimization program the control signal is calculated from a plurality of individual control signals, and wherein, via the individual control signals, different partial light distributions, each dependent on the environmental parameters, are generated.

2. The headlight according to claim 1, wherein each environmental parameter from a plurality of environmental parameters is assigned a separate individual control signal via which the partial light distribution related to the environmental parameters are generated.

3. The headlight according to claim 1, wherein the environmental parameter provides light distribution-relevant individual information about the environmental conditions.

4. The headlight according to claim 1, wherein the individual control signal is formed as a digital signal which is either in an on state or in an off state or in a number of stages.

5. The headlight according to claim 1, wherein a database is provided to store individual control signals that represent respective environmental parameters.

6. The headlight according to claim 1, wherein the control unit is coupled to a detection unit and/or to an external transmission device via a communication network for detecting environmental parameters.

7. The headlight according to claim 6, wherein the optimization program is designed such that current environmental parameters provided by the external transmission device are in each case compared for correspondence with the respective current environmental parameters provided by the detection unit, and wherein, if a deviation is detected between the respective environmental parameters, the respective environmental parameter provided by the detection unit is used to form the individual control signal.

8. The headlight according to claim 1, wherein the control unit has a processor via which the presence or absence of the individual control signals is determined by comparison of the current environmental parameters provided by the detection unit and/or the external transmission device with the environmental parameters stored in the database, and wherein the control signal is calculated from the currently present individual control signals via the optimization rule.

9. The headlight according to claim 1, wherein the optimization program is designed such that spatial positions of the different present partial light distributions are compared with one another with respect to their illuminance values and the control signal is determined for each spatial position using an optimization rule.

10. The headlight according to claim 1, wherein the optimization rule is designed such that the maximum or optimal illuminance value of the spatial position is selected from the partial light distributions in each case.

11. The headlight according to claim 1, wherein the individual control signals of the different environmental parameters are provided weighted according to a weighting rule.

12. A method for controlling a headlight according to claim 1, the method comprising: assigning stored individual control signals to environmental parameters in order to generate partial light distributions, which are dependent on the respective environmental parameters; determining a presence or absence of the environmental parameters by a detection unit of the vehicle and/or by a transmission device connected via a communication network; and calculating the control signal as a function of the current presence of the environmental parameters in accordance with an optimization rule.

13. The method according to claim 12, wherein, after determination of the current individual control signals, specifying the respective different partial light distributions, the location-related illuminance values of the partial light distributions are compared with one another and the illuminance values of the light distribution generated by the control signal are calculated location-related according to the optimization rule.

14. The method according to claim 12, wherein the control signal is calculated from the weighted or non-weighted individual control signals.

15. The method according to claim 12, wherein, via the optimization rule, the respective location-related maximum illuminance values of the partial light distributions are used to determine the control signal.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0021] FIG. 1 is a block diagram of a headlight of the invention;

[0022] FIG. 2 shows an allocation table of various environmental parameters to partial light distributions;

[0023] FIG. 3a shows a partial light distribution in the area in front of the vehicle for the environmental parameter “road course straight”;

[0024] FIG. 3b shows a partial light distribution in the area in front of the vehicle for the environmental parameter “road course to the left”;

[0025] FIG. 3c shows a partial light distribution in the area in front of the vehicle for the environmental parameter “road course to the right”;

[0026] FIG. 3d shows a partial light distribution in the area in front of the vehicle for the environmental parameter “pedestrian on right”;

[0027] FIG. 3e shows a partial light distribution in the area in front of the vehicle for the environmental parameter “pedestrian on left”;

[0028] FIG. 3f shows a partial light distribution in the area in front of the vehicle for the environmental parameter “oncoming traffic present”;

[0029] FIG. 3g shows a partial light distribution in the area in front of the vehicle for the environmental parameter “oncoming traffic absent”;

[0030] FIG. 4 shows a resulting light distribution in the area in front of the vehicle; and

[0031] FIG. 5 shows a flowchart of the lighting control system.

DETAILED DESCRIPTION

[0032] A headlight for vehicles is located in a front-end area of a vehicle. It comprises a light source unit 1 with a plurality of light sources 2 arranged in a matrix-like manner. Light sources 2 are preferably designed as LED light sources arranged on a common support. The LED light sources 2 are arranged in a matrix-like manner with a predefined number, so that a pixel light system with a plurality of small pixels of a light distribution L can be generated by means of such a matrix headlight.

[0033] To depict the light emitted from light sources 2, an optical unit 4 is provided, which has, for example, a predefined number of lenses. The headlight can be designed as a scanning headlight, wherein the light source is designed as a laser light source and optical unit 4 as a deflection unit. Alternatively, optical unit 4 can also have a plurality of liquid crystal elements or micromirror elements, so that suitable controlling of optical unit 4 results in an LCD pixel light system (LCD=liquid crystal display) or a micromirror-based pixel system (DMD=digital micromirror device). Depending on the design of optical unit 4, a control signal 6 is emitted by means of a control unit 5 to light source unit 1 and/or a control signal 7 is emitted to optical unit 4, by means of which the light distribution L shown in FIG. 4 is generated.

[0034] Control unit 5 has an optimization program 8 by means of which control signal 6, 7 is generated. For this purpose, optimization program 8 takes into account current environmental parameters 9, which can be provided by a detection unit 10 coupled to control unit 5. For example, detection unit 10 can include a camera and/or sensors.

[0035] Alternatively or in addition, control unit 5 is coupled via a communication network 11 (for example, the Internet) to a transmission device 12, which transmits, for example, weather data and/or road condition data or the like as environmental parameters 13. For example, transmission device 12 can be cloud-based or integrated into another vehicle, preferably a vehicle in front.

[0036] Different categories of environmental parameters 9, 13 that are taken into account in generating the light distribution L are listed in FIG. 2. The first category concerns the “road course” category, wherein “road course straight,” “road course to the left,” and “road course to the right” are specified as environmental parameters. Alternatively, refinements of this category with multiple possibilities can be provided. The second category concerns the “number of pedestrians,” wherein “pedestrians on left few,” “pedestrians on left many,” “pedestrians on right few,” and “pedestrians on right many” are specified as environmental conditions. Each of these preselected environmental conditions is assigned a partial light distribution TL1, TL2, TL3 . . . Tn. The corresponding partial light distribution TL1, TL2 . . . TLn can be generated by a corresponding individual control signal A1, A2, A.sub.n, with which light source unit 1 and/or optical unit 4 are controlled. In contrast to the category “road course”, where different road courses are queried, a number range of the presence of pedestrians on the left and/or right side is also queried in the category “pedestrians.” Depending on the pedestrian traffic, pedestrians can thus be optimally taken into account in the light distribution L.

[0037] In the third category, “oncoming traffic”, the presence and absence of oncoming traffic is taken into account. In the fourth category, the current weather is taken into account. In the fifth category, the road surface is taken into account. In the sixth category, the location of the vehicle is taken into account. The nth category can concern the street lighting, for example. The number of categories is arbitrary; it depends on the accuracy requirement.

[0038] Different partial light distributions associated with corresponding environmental parameters 9, 13 are shown in FIG. 3. The environmental parameters 9, 13 thus provide light distribution-relevant individual information about the environmental conditions of the vehicle, wherein the individual control signals A1, A2, A.sub.n required in each case for generating the partial light distribution TL1, TL2, . . . TLn are stored in a database 14 connected to control unit 5.

[0039] The optimization program 8 is designed such that the categories or the presence or absence of the total number of environmental parameters 9, 13 are queried sequentially, wherein there are only two binary signals for each query, namely “1” for presence and “0” for absence. This is done in step S1 according to FIG. 5. In each case, the signal is a digital signal which, according to an embodiment which is not shown, can also be present in a number of stages (dimming stages).

[0040] If the presence of an environmental parameter is affirmed, this means that corresponding individual control signals A1 . . . A.sub.n, stored in database 14, are taken into account for determining control signal 6, 7. Environmental parameters that are currently not present and to which the digit “0” is assigned have the effect that the corresponding control signal A1 is not taken into account for determining control signal 6, 7.

[0041] Control unit 5 has a microprocessor as a processor/computing component 15, by means of which the optimization program is run.

[0042] In a further step S2, the optimization program applies an optimization rule by means of which control signal 6, 7 is generated from the relevant individual control signals A1 . . . A.sub.n marked with “1.” According to a first variant of the optimization rule, identical pixel-like spatial positions or pixel-like location coordinates K1, K2, Kn of the partial light distributions TL1 . . . TLn assigned to the respective present environmental parameters are checked to determine which of the partial light distributions TL1 . . . TLn provides the maximum illuminance value. This is then used for the resulting light distribution L in the further step S3. In the present exemplary embodiment, the environmental parameters regarding “road course straight,” “pedestrians on left few,” “pedestrians on right many,” “oncoming traffic yes,” “weather dry,” “road surface asphalt,” and “city street” are present, so that the partial light distributions TL1, TL4, TL7, TL8, TL12, TL13, TL16 are linked together. This is done in such a way that these partial light distributions TL1, TL4, TL7, TL8, TL12, TL13, TL16 are “superimposed” as it were and the maximum illuminance values at the respective location coordinates K1, K2, Kn of these partial light distributions TL1, TL4, TL7, TL8, TL12, TL13, TL16 are determined, from which the current light distribution L is then formed. The corresponding control signal is determined by optimization program 8 and transferred to light source unit 1 and/or optical unit 4 in step S3.

[0043] According to an alternative embodiment of the invention (not shown), the partial light distributions TL1, TL2, . . . TLn or the corresponding individual control signals A1, A2, An assigned to the respective environmental parameters present can be weighted according to a weighting rule to determine the control signal. In the present exemplary embodiment, it is assumed that all relevant categories with the same proportion of illuminance values are compared with one another and the maximum illuminance value related to the location coordinates K1, K2, Kn of the maximum illuminance value is used. If, for example, the fifth category “road surface” should have a subordinate importance compared to the other categories, the corresponding individual control signal can be included not with a factor of 1, but with a factor between 0 and 1. For example, if the fifth category at a certain location K1, K2, Kn specifies the maximum illuminance value, it would be correspondingly smaller, for example, decrease to half, if the weighting factor is 0.5, and thus the illuminance value in the light distribution L at this spatial position would be smaller.

[0044] As can be seen in FIG. 5, the current environmental parameters are queried continuously and repeatedly, so that the light distribution L can be changed or adjusted immediately if the environmental conditions change.

[0045] The invention being thus described, it will be obvious that the same may be varied in many ways. Such as variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.