DE102004037870B4 - Optical module for an outer vestibule in the direction of travel of a motor vehicle detecting assistance system - Google Patents

Abstract

Optical module (1) of an outer vestibule (50) in the direction of travel of a motor vehicle detecting assistance system, with
- At least a first circuit carrier (10);
- At least one on the first circuit carrier (10) arranged first semiconductor element (12);
- wherein the sensitive surface (34) of the first semiconductor element (12) is a high-resolution 2D image sensor (34);
- With a second semiconductor element (13) whose sensitive surface (35) is designed as a 3D-term sensor; and
- At least one lens unit (14; 16, 18) for projecting electromagnetic radiation on a sensitive surface (34) of the first semiconductor element (12);
characterized,
- That in the beam path (Vis + IR) of the optical module (1) a beam splitter or mirror (28) is arranged, which electromagnetic radiation wavelength specific (Vis; IR) on the sensitive surfaces (34, 35) of the first (12) and second (13) semiconductor element distributed;
- That the beam splitter or mirror (28) is a so-called. "Hot-cold-mirror", which the electromagnetic radiation (Vis + ...

Description

The The invention relates to an optical module of the outer vestibule in the direction of travel of a motor vehicle detecting assistance system, with the features of the preamble of patent claim 1.

On the driving environment of a motor vehicle directed sensor systems find more and more application in the motor vehicle of the near future. there are various assistive systems conceivable, which the driver support Offer. As examples can Track Recognition or Monitoring Applications, Night Vision Applications, Obstacle warning, pre-crash sensing, automatic speed adaptation, Traffic Jam Assistant, Pedestrian and Bicycle rider protection, traffic sign recognition, parking assistance and such more.

The Requirements for such assistance systems are sometimes very different. Common to them is the requirement, as realistic a representation as possible to generate the environment. For example, lanes in front of the vehicle also in big ones intervals to recognize, is a camera with a relatively high-resolution optical module needed.

Around Objects such as other motor vehicles, cyclists and / or pedestrians too recognize, is next to a camera image also a distance measuring System helpful, especially on radar or lidar technologies based.

For a capture of the outer vestibule in the direction of travel of a motor vehicle is known, for example a high resolution 2D camera with, for example, 300k pixels, which e.g. lanes recognizes and / or records and classifies objects.

It is also known to use a light-time-based lidar sensor for distance measuring systems. Such lidar sensors also exist in the form of a pixel matrix implemented in CMOS technology. Such, for example from the EP 1 159 636 B1 or DE 101 38 531 A1 known so-called TOF (Time of Flight) CMOS array can generate a depth image of a scene with many sampling points by means of pulsed illumination. In addition to the depth image, a grayscale image can also be evaluated. However, this is limited to a small number of eg 1 to 3000 (3k) pixels, since the amount of light emitted can not be increased arbitrarily and a compromise between the amount of light, number of pixels, distance range and cost must be found. Thus, it is not possible to use this CMOS pixel matrix measuring a distance for a high-resolution 2D image as well.

In a motor vehicle so far, each has a separate system for the 2D acquisition and one for the 3D detection are implemented, which is why therefore considerable Costs go along. About that have to go out the only available individually Systems are networked, one wants a picture as complete as possible capture the driving environment and thus build up a correspondingly secure system. Because also the space in a motor vehicle often very limited it is frequent difficult to accommodate two different systems simultaneously.

Such devices are for example from the DE 196 03 276 A1 and the GB 2 374 228 A known. In both cases, in each case in addition to a high-resolution 2D image sensor, which may be formed for example as a CCD camera, a 3D runtime sensor is used. The beam paths are preferably, as shown in the GB 2 374 228 A is disclosed, guided so that in each case a coincident observation area for the two image systems can be detected. The disadvantage here, however, the effort that is due to the see before by two different imaging systems. For this reason, in the GB 2 374 228 proposed to carry out both evaluations by means of a special method by a single photosensitive sensor and a corresponding downstream evaluation device.

Such a method and a device for determining the phase and / or amplitude information of an electromagnetic wave is also in the EP 1 009 984 B1 described. In this case, both the amplitude information and the phase information of an electromagnetic wave are evaluated by a specific correlation technique.

adversely Here, however, the high computational effort in the evaluation of Signals or the circuit complexity for the realization of Correlation.

It object of the present invention, which is known from the prior art to avoid known disadvantages.

This object is achieved by the features of the independent claims. Advantageous embodiments and developments, which can be used individually or in combination with each other, are the subject the respective dependent claims.

The Invention is based on generic optical Modulon on that the sensitive surface of the first semiconductor element a high resolution Is 2D image sensor; and that a second semiconductor element is provided is whose sensitive area is designed as a 3D runtime sensor.

On the first circuit carrier can arranged both the first and the second semiconductor element be.

For the purpose of increase constructive degrees of freedom is proposed, a first and to arrange second semiconductor element on different circuit carriers.

According to the invention is in Beam path (Vis + IR) of the optical module, a beam splitter or mirror arranged, which electromagnetic radiation wavelength specific (Vis; IR) on the sensitive surfaces of the first and the second semiconductor element distributed.

ever according to the structural design of the optical module is the beam splitter or mirrors below 30 ° to 60 °, preferably below 45 ° in the Beam path (Vis + IR) of the optical module arranged.

According to the invention is a so-called "hot-cold-mirror" as a beam splitter or mirror which uses electromagnetic radiation (Vis + IR) is divided into two components, one in which the visible one Includes light (Vis) and in one, which longer wavelength as the near infrared (IR) includes.

To the invention, the visible light (Vis) on the sensitive area of the first semiconductor element and longer wavelengths such as the near infrared (IR) on the sensitive surface of the second semiconductor element guided.

Of the used beam splitter or mirror has thus advantageous a kind of filter function, by the respective semiconductor element only the corresponding wavelength or light components, which are also used.

Conveniently, the infrared light component (IR) originates from at least one of the optical module associated infrared light source.

The resolution the lens unit for projecting electromagnetic radiation finally is from the spectral range essentially to the high-resolution 2D Sensor tuned, because for the much smaller number of pixels and the sake of sensitivity rather larger pixels of the 3D sensor is a much lower resolution and sharpness (MTF) necessary.

The The present invention allows for the first time the inexpensive Construction of only one optical module with a completed 2D / 3D Unit. About that can out these units of the optical module already in the production of each other be tuned or calibrated to each other, so that complex networking work - as in State of the art necessary - advantageous omitted.

additional Details and further advantages of the invention are given below on hand preferred embodiments in conjunction with the attached Drawing described.

The single FIGURE shows a schematic diagram of an embodiment of an optical module 1 ,

This is based on the basic idea, an optical detection unit 1 which absorbs light in the entire spectral range from visible (Vis) to near infrared (IR). There are so-called "hot / cold mirrors" or "cold / hot mirrors" on the market. 28 It is possible to divide the wavelength range of the light into two components, namely one which encloses the visible light (Vis) and one which comprises longer wavelengths such as the near infrared (IR).

Depending on the version of the mirror 28 , one component (Vis or IR) is reflected and the other is transmitted or vice versa. Another criterion in this regard is the angle at which the mirror 28 in the beam path (Vis + IR) is arranged.

The mirror 28 is - as shown - for example, at an angle of 45 degrees in the beam path (Vis + IR) brought. It can thus send the signal wavelength-specific to two different detectors 34 and 35 to lead. Shown is a so-called "hot-mirror" 28 which is permeable to shorter wavelength ("cold") wavelengths, ie visible light (Vis), and which reflects or reflects longwave ("hot") wavelengths, in particular IR rays, upwards.

The detectors are preferably sensitive surfaces 34 ; 35 two semiconductor elements 12 ; 13 , which in the embodiment depending on its own circuit carrier 10 . 11 are arranged, which advantageously the design freedom of the optical module 1 elevated.

In the specific case illustrated, the visible light detector (Vis) is a high resolution 2D image sensor 34 example way to detect lanes and / or objects in the outer lobby 50 a motor vehicle.

In contrast, the detector for the infrared light (IR) is a 3D transit time sensor 35 , which in any case preferably only with its own infrared light source (not shown) of the optical module 1 works - for the 35 Thus, only the infrared light component (IR) is relevant.

The advantage of such an optical module 1 There is one in the cost, it has only one optical unit 14 ; 16 . 18 be built, and the module 1 includes a completed 2D / 3D unit 12 . 34 ; 13 . 35 , Another advantage is that the sensor units 12 . 34 and 13 . 35 Already coordinated during production, the 2D and 3D data can be calibrated to each other.

In addition, the used beam splitter or mirror 28 already a filter function for the corresponding wavelengths. He 28 leads to the respective sensor 34 ; 35 only the light components, which are also used.

The resolution of the optics 14 ; 16 . 18 comprising a lens holder 14 as well as a first 16 and second 18 Lens, of the spectral range essentially only needs the high-resolution sensor 34 be optimized because of the much smaller number of pixels and for sensitivity reasons anyway rather larger pixels of the 3D sensor 35 a much lower resolution and sharpness (MTF) is necessary.

In that regard, the present invention allows for the first time the inexpensive construction of only one optical module with a closed 2D / 3D unit, which is especially for the outer vestibule 50 in the direction of travel of a motor vehicle detecting assistance systems such as lane detection or monitoring applications, night vision applications, obstacle warning, pre-crash sensing, automatic speed adaptation, congestion assistant, pedestrian and cyclist protection, traffic sign recognition and the like is more suitable.

Claims (6)

Optical module ( 1 ) one the outer vestibule ( 50 ) in the direction of travel of a motor vehicle detecting assistance system, with - at least a first circuit carrier ( 10 ); At least one on the first circuit carrier ( 10 ) arranged first semiconductor element ( 12 ); - where the sensitive surface ( 34 ) of the first semiconductor element ( 12 ) a high-resolution 2D image sensor ( 34 ); With a second semiconductor element ( 13 ) whose sensitive area ( 35 ) is designed as a 3D runtime sensor; and - at least one lens unit ( 14 ; 16 . 18 ) for projecting electromagnetic radiation onto a sensitive surface ( 34 ) of the first semiconductor element ( 12 ); characterized in that - in the optical path (Vis + IR) of the optical module ( 1 ) a beam splitter or mirror ( 28 ), which electromagnetic radiation wavelength-specific (Vis; IR) on the sensitive surfaces ( 34 ; 35 ) of the first ( 12 ) and the second ( 13 ) Distributed semiconductor element; - that the beam splitter or mirror ( 28 ) is a so-called "hot-cold-mirror" which divides the electromagnetic radiation (Vis + IR) into two components, namely one which encloses the visible light (Vis) and one which has longer wavelengths such as the near infrared (IR); and - that the visible light (Vis) on the sensitive surface ( 34 ) of the first semiconductor element ( 12 ) and longer wavelengths like the near infrared (IR) - the sensitive area ( 35 ) of the second semiconductor element ( 13 ) to be led. Optical module ( 1 ) according to claim 1, characterized in that on the first circuit carrier ( 10 ) both the first ( 12 ) as well as the second ( 13 ) Semiconductor element are arranged. Optical module ( 1 ) according to claim 1, characterized in that the second semiconductor element ( 13 ) on its own second circuit carrier ( 11 ) is arranged. Optical module ( 1 ) according to one of the preceding claims, characterized in that the beam splitter or mirror ( 28 ) at 30 ° to 60 °, preferably at 45 ° in the optical path (Vis + IR) of the optical module ( 1 ) is arranged. Optical module ( 1 ) according to one of the preceding claims, characterized in that the infrared light component (IR) of a the optical module ( 1 ) associated infrared light source comes. Optical module ( 1 ) according to one of the preceding claims, characterized in that the resolution of the lens unit ( 14 ; 16 . 18 ) for projecting electromagnetic radiation from the spectral region substantially onto the high-resolution 2D sensor ( 34 ) is tuned.