DETAILED DESCRIPTION OF THE INVENTION

[0019] The invention discloses improving an operator control so as to reduce disruptive image components which are faded into the driver's field of vision, and an operator control which is ergonomic.

[0020] In one embodiment of the invention, the image of the driver's hand is recorded by the video camera, but is not faded directly into the driver's field of vision. Rather, it is used to determine the position of the driver's hand. In accordance with the determination of the position of the driver's hand, a virtual image pointer is then faded into the driver's field of vision by a visual display unit. In this regard, disruptive optical background signals in the image recorded by the video camera, such as parts of the center console, are faded out.

[0021] Accordingly, the operator control according to the invention has a sensor which senses the position of an input element which is controlled manually by the operator. The input element can be, for example, the operator's hand or index finger. However, it is also possible for the operator to hold a separate input element which interacts with the sensor in order to permit the position to be determined. A video camera, such as an infrared camera, an ultrasonic sensor, a radar sensor, a capacitive sensor or a contact sensor, (i.e. what is commonly referred to as a touchpad) is preferably suitable here as sensor.

[0022] Furthermore, the operator control according to the invention has a visual display unit which is arranged in the operator's field of vision and displays at least one virtual operator element and the virtual image pointer. The display unit preferably includes a head-up display which can project an image directly into the operator's field of vision.

[0023] Moreover, in the operator control according to the invention, an evaluation unit which is connected to the sensor on the input side and which determines the position of the manually controlled input element is provided.

[0024] Finally, an image generator is provided, which is connected to the evaluation unit on the input side and to the display unit on the output side. The image generator displays a virtual image pointer in the operator's field of vision in accordance with the position of the manually controlled operator element.

[0025] In a preferred embodiment of the invention, the evaluation unit is connected on the output side to a comparator unit. The comparator unit compares the position, determined by the evaluation unit, of the manually controlled operator element with predefined position data and generates a control signal as a function of the result of the comparison. The predefined position data preferably corresponds to the positions of the individual virtual switching elements to be activated, such that the user moves the manually controlled input element into a desired spatial region in order to trigger a switch activation.

[0026] Preferably, the comparator unit is connected on the output side to a loudspeaker in order to audibly display a possible activation, and/or an activation which has taken place, of a virtual operator element. In this way, it is possible, for example, to give the operator audible feedback by outputting an audible signal if the manually controlled input element is located in an activation position in front of a switching element. The operator knows, for example, that the manually controlled input element, such as an index finger, merely has to be pressed toward the front in order to activate the operator element, after which a further audible element is then output, which preferably differs from the first audible signal, in order to indicate that the operator element has been activated.

[0027] In another embodiment of the invention, the evaluation unit is connected on the output side to a limiter which limits the position data, determined by the evaluation unit, of the manually controlled input element to predefined values. In this way, it is possible, for example, to prevent the virtual image pointer faded into the operator's field of vision from moving out of the operator's field of vision when he makes a hand movement which misses the mark. The virtual image pointer instead remains at the limits of the field of vision in order to facilitate repositioning by the operator. The limiter is also preferably connected on the output side to a loudspeaker in order to give the operator audible feedback so that the loudspeaker outputs an audible warning signal if the operator's hand moves out of the operator control region.

[0028] The perspective view illustrated in FIG. 1 shows a motor vehicle interior with a driver 1 and a video camera 2 which is arranged in the roof lining above the center console and which is directed downward onto an operator control area 3 lying in the region of the center console. The operator control area 3 includes, in contrast to conventional operator controls, no switching elements or operator elements which are actually embodied. Rather, they serve as a contact face for an index finger 4 of the driver 1 , which serves as an input element. The image of the operator control area 3 , which is picked up by the video camera 2 , includes, as information, the position of the driver's index finger 4 .

[0029] Furthermore, the operator control according to the invention has a head-up display 5 which is illustrated schematically in FIG. 2 . The structure of such a head-up display 5 is described in detail in German laid-open application DE 196 20 199 A1. On the one hand, the head-up display 5 fades virtual operator elements 6 into the field of vision of the driver 1 , and the virtual operator elements 6 can be virtual switches, for example. On the other hand, the head-up display 5 projects a virtual image pointer 7 into the field of vision of the driver 1 .

[0030] The video camera 2 is connected on the output side to an image analyzing unit 8 which serves as an evaluation unit and which analyzes the image of the hand of the driver 1 which is picked up by the video camera 2 , and determines the spatial position of the tip of the index finger 4 and outputs it in the form of position data X, Y, Z.

[0031] A limiter 9 is connected downstream of the image analyzing unit 8 and compares the position data X, Y, Z, calculated by the image analyzing unit 8 , of the tip of the index finger with predefined position data which limit the operator control area 3 . If the driver 1 moves his/her index finger 4 out of the operator control area, the position data X, Y, Z of the tip of the index finger 4 are limited to the limiting values X _LIM , Y _LIM , Z _LIM at the boundaries of the operator control area 3 .

[0032] Furthermore, the limiter 9 is connected on the output side to a loudspeaker 10 which outputs an audible warning signal if the user's hand leaves the operator control area 3 .

[0033] On the output side, the limiter 9 is connected to a comparator unit 11 which compares the limited position data X _LIM , Y _LIM , Z _LIM with predefined position data, which correspond to the virtual positions of the operator element 6 . If the driver 1 moves his/her index finger 4 in such a way that the tip of the index finger 4 is located in the region of the virtual positions of the switching elements 6 , the comparator unit 11 outputs a corresponding control signal CONTROL in order to trigger the function which is associated with the respective operator element 6 . In this case, the comparator unit 11 activates the loudspeaker 10 in order to generate an audible feedback signal which indicates to the driver 1 that the respective operator element 6 has been successfully activated. In addition, the comparator unit 11 is connected on the output side to an image generator 12 , which drives the head-up display 5 so as to display the virtual operator elements 6 . The operator element activated by the driver 1 is displayed in a different color after successful activation, such that the driver 1 receives not only an audible feedback signal by the loudspeaker 10 , but also a visual feedback signal as a result of the operator element 6 being achieved in a different color in the head-up display 5 .

[0034] The operator control according to the invention also has an image generator 13 which is connected on the input side to the limiter 9 , and drives the head-up display 5 so as to display the virtual image pointer 7 as a function of the position data X _LIM , Y _LIM and Z _LIM limited by the limiter 9 .

[0035] The exemplary embodiment illustrated in FIG. 3 coincides largely with the exemplary embodiment described above and shown in FIGS. 1 and 2 , so that in what follows the same reference symbols are used and reference is made to the above description in order to avoid repetitions.

[0036] The particular feature of the exemplary embodiment according to FIG. 3 is that the sensor 2 is not a video camera, but rather a touch-sensitive touchpad which outputs the position at which the driver touches the touchpad.

[0037] The invention is not restricted to the exemplary embodiment described above. Instead, it is possible to conceive of a multiplicity of variants and modifications which make use of the idea according to the invention and therefore also fall within the scope of protection.