DE10310264A1 - Catadioptric camera for a technical device, in particular a motor vehicle - Google Patents

Abstract

The invention relates to a catadioptric camera for a technical device, in particular a motor vehicle. The catadioptric camera comprises an image sensor for environmental detection, wherein the image sensor consists of an optical-electrical converter and an associated optics. When the environmental information, in the form of optical radiation, is detected, it is reflected by at least one mirror before impact with the image sensor, wherein the mirror preferably has a conical cross section for reflection of the optical radiation in order to realize a larger detection range compared to conventional cameras. The mirror is in this case arranged separately from the image sensor, in particular attached directly to the outer skin of the technical device or to attachments of the technical device. Due to this modular design, the device can be manufactured with little effort and integrated in a simple way in a motor vehicle, the vehicle design remains largely unchanged, since only the mirror of the catadioptric camera is visible in the environment of the vehicle.

Description

The invention relates to a catadioptric camera for one technical device, in particular a motor vehicle.

In support of the driver will be future vehicles equipped with environmental sensing systems. Such systems serve to protect the driver from obstacles and other sources of danger to warn in order to reduce the number of traffic accidents. By the electronic detection of the dead angle, for example, the driver be supported significantly when parking. The detection of the environment information takes place by means of imaging Sensors. You can do this For example, CCD sensors, which are sensitive in the visible spectrum are, or infrared sensors are used. A very essential Point in the use of such sensors in vehicles is the installation site, this one hangs not solely on the task and thus on the task to be grasped Range, but it must also requirements for the vehicle design and others for the operation the system relevant parameters are taken into account. The means Environmental information recorded in an environment detection system can be displayed to the driver, for example, directly on a display or forwarded to in-vehicle systems for evaluation become.

In Scripture JP 60240545 a device for automatic control of control units of a motor vehicle is described, which should assist the driver in particular when entering tunnels. Here, an environment detection unit is used, which essentially comprises an optical system, a light guide and an image sensor. The optics serve to image the light reflected from the environment ahead of the vehicle onto the light guide. Subsequently, the light is guided via the light guide to the image sensor. Wherein the image sensor comprises a CCD chip and a register by means of which generates a video signal. The video signal is evaluated as to whether the vehicle is ahead of a tunnel. In the event that a tunnel is detected, for example, the headlights can be automatically activated, and the windows of the motor vehicle can be closed.

In Scripture DE 20115924 U1 An optical fiber imager for automobiles is described. The image recorder consists of a video camera, a lens, a fiber optic cable and a monitor screen. Where the lens is attached to one end of the fiber optic cable in order to be able to record suitable images. Several fiber optic cables and lenses are each attached to a suitable location on the vehicle. The assembly of the fiber optic cable takes place here in direct connection with the vehicle, for example on the side mirrors, on the bumpers or on the tail lights.

Systems which for optical display of the dead angle in motor vehicles are from the published patent application WO 98/09185 known. Such systems transfer an optical image for this purpose between two different places by means of a bundle coherent optical fiber optic cable. This is at the ends of a fiber optic bundle respectively a planar microlens array attached. On the one hand serve the Microlenses to the optical radiation from the environment in a suitable Way to couple into the core of Lichtwellenlei ter. On the other hand With the microlenses, the optical radiation, after getting these along the optical fiber has spread, in a suitable Way forwarded to the display position. The display can be here directly or by means of a CCD chip and video monitor.

In the utility model application DE 29806638 U1 a camera monitoring unit to be arranged in the rear area of a motor vehicle is presented. The camera monitoring unit comprises an electronically operated recording camera, as well as a visible to the driver image display and / or display device. The recording camera is installed on a strip conductor or the like, one or more dimensional circuit carrier of a taillight unit installed. Preferably, the camera is installed with its electrical and mechanical connecting elements at an approximately centrally located in the rear region of the motor vehicle additional (third) equipped with light emitting diode taillight unit. However, the monitorable area significantly depends on the location of the tail light. In addition, such a device can be produced only with great effort, which in turn has correspondingly high costs for the purchase and repairs.

The invention is therefore the task At the bottom, a device for monitoring the environment of a technical device, in particular of a motor vehicle to create by means of an environmental sensor, which one as possible greater Range can be recorded and where the cost of production the device as possible is low.

The object is according to the invention solved by a device having the features of claim 1. advantageous Embodiments and developments are shown in the subclaims.

According to the invention, a catadioptric camera for a technical device, in particular a motor vehicle, is provided. This before Direction includes at least one image sensor for environmental detection, wherein the image sensor consists of an optical-electrical converter and an associated optics. In the detection of the environmental information, in the form of optical radiation, this is reflected before hitting the image sensor at least one mirror. In an inventive manner, the mirror for reflecting the optical radiation is mounted separately from the image sensor, in particular directly on the outer skin of the technical device and / or attached parts of the technical device. In an advantageous manner, the environment information detected thereby can be made available to the user of the technical device and / or internal systems of the technical device.

In a particularly advantageous manner can the Use device in connection with a motor vehicle, below Now the subject of the invention based on such an automotive application be described in detail. With the present invention is created a modular structure of the environment detection system, by the mirror separated from the image sensor directly on the motor vehicle is attached. Due to this modular structure, the system can be set to one create a particularly simple way. Where the mirror is optional, as additional Component, on the body or on the attachments of the motor vehicle can be attached. For example, it is conceivable that the mirror on the bumpers, side mirrors, on cover glass of lighting units or any other Attachments of the motor vehicle is attached.

In addition to the image sensor associated optics can by the use of other optical means, which in the Beam path between image sensor and mirror are introduced, extends the system for environment detection in an advantageous manner become. As another optical means, e.g. optical Lenses the image of the optical radiation on the image sensor. It is conceivable that a whole system of optical lenses in the Beam path is introduced in order to minimize aberrations. Belonging to the aberrations For example, chromatic aberration, coma, astigmatism and Field curvature.

However, it is special in one advantageous manner also conceivable as another optical means a bunch single optical fiber (LWL) in the beam path between the image sensor and mirror to bring. An advantage here is that the image sensor not necessarily be mounted in the direct field of view to the mirror got to. Thus, the mounting of the image sensor in a protected place take place, for example, in a space between the vehicle body behind a panel. Whereby in a further advantageous Embodiment of the invention is also conceivable, several mirrors attach to the vehicle and the optical radiation reflected therewith to image on a single image sensor. Here are several Fiber to a fiber optic bundle summarized. For the image transfer using fiber optic bundle However, it is necessary that at both end faces the fibers in the same order are arranged in order to avoid information distortions. That's why is also a use of fiber rods conceivable in which the individual fibers fused together. Fiber rods have the property that these under supply of heat can be bent, also later after the end faces already finished. In particular, on the production technology affects the fiber rods their rigid structure disadvantageous, but this disadvantage is characterized balanced, that is the order of the individual fibers during installation in a system does not change.

In a further advantageous embodiment of The invention relates to the mirror on which the optical radiation is reflected to cut a mirror with a conical cross. Under conical in the The meaning of this invention is understood to mean a shape of the mirror, in which of these a paraboloid or hyperboloid or a Combination of conic sections (parabola, hyperbola, ellipse) corresponds. Such mirrors are preferably used in panoramic cameras used, for example, in the document "Folded Catadioptric Cameras, "by Shree K. Nayar and Venkata Peri, link hyperlink www.cs.columbia.edu/ CAVE / publinks / nayar_cvpr_1999_1.pdf. For catadioptric Camera systems with folded beam path are there next to planar Mirroring e.g. also proposed parabolic and hyperbolic mirrors. Here, the image sensor and the mirror form a compact, constructive Unit. A significant advantage in the use of such mirrors with conical Cross-section is that hereby a much larger surrounding area detectable than would be the case with a single planar mirror. Thus it is e.g. also possible that the entire range of 360 ° around the vehicle is detected by at least two mirrors attached to the vehicle become. Preferably, each one of these mirrors on the diagonally opposite extreme Corner of the vehicle is attached.

In a further embodiment, the mirror for reflecting the optical radiation is advantageously attached to a lighting unit, in particular to an illumination cover of the motor vehicle. In this case, the mirror is preferably mounted directly behind the respective lighting cover and thus hardly visible to persons located in the environment of the motor vehicle. On the one hand, this results in a largely neutral appearance, which is often required in terms of vehicle design. On the other hand, every time you wash the lighting covers, it also becomes the field of vision the camera cleaned. Lighting covers are also usually attached to those positions of a motor vehicle, which hardly pollute due to their aerodynamic properties or have a self-cleaning property.

In a particularly advantageous manner can the device of the invention be used in a motor vehicle, in this case in particular the mirror at the vehicle rear is mounted in the area of the trunk handle. The attachment of the Device at the back of the motor vehicle is suitable, for example, for use as Parking aid. The device being an electronic rearview mirror serves and the driver the recorded environmental data in the form images directly on a display. however it is also conceivable that the acquired environmental data for evaluation be forwarded to in-vehicle systems. For example the evaluation is carried out by means of image processing methods. the Persons skilled in this are known methods by means of which a motion analysis or a distance determination can be performed. These include u.a. optical flow, the tracing of features in the image and the evaluation perspective views by means of inverse illustration. Of course you can the device according to the invention application specific be attached to other locations of the motor vehicle, for example, can the mirror in the 3rd brake light (rear, center) on the vehicle be integrated. Other applications are here, for example the lane assistant, which the driver when leaving the lane by a signal warns. When used as an electronic mirror for monitoring of the Dead Angle, the driver is warned of obstacles that he otherwise could not see.

Of course, the invention is not limited to use in motor vehicles, but it is also one Use in connection with work machines conceivable. For example used in the production area driverless transport systems, in which is the device of the invention in particular for monitoring the Dead angle is suitable. Also it is possible to put the mirror on one Robotic arm to install, in particular for the observation of poorly visible Areas.

Other features and benefits of Invention will become apparent from the following description of embodiments from the automobile sector based on the figures. Showing:

1 Basic structure of the catadioptric camera.

2a Perspective view of a known from the prior art attachment of a camera.

2 B Side view of a known from the prior art attachment of a camera.

3a Perspective view of the integration of a catadioptric camera on a motor vehicle.

3b Side view of the integration of a catadioptric camera on a motor vehicle.

In 1 the basic structure of the catadioptric camera is shown. Where the optical radiation at a mirror ( 4 ) is reflected such that this in the direction of the image sensor ( 1 ) is deflected. The image sensor ( 1 ) comprises an optic ( 3 ), which transmits the optical radiation to the optical-electrical converter ( 2 ) maps. By means of the optical-electrical converter ( 2 ), the optical radiation is converted into an electrical camera signal. The device according to the invention provides that the mirror ( 4 ) separated from the image sensor ( 1 ) is arranged. Alternatively, between the image sensor ( 1 ) and the mirror ( 4 ) further optical means ( 5 ) can be introduced into the beam path, for example in order to minimize image errors.

2a shows the perspective view of a known from the prior art attachment form a camera ( 10 ) at the rear of a motor vehicle. The camera ( 10 ) is attached here next to the trunk handle. This recessed position, which has been aerodynamically designed so that the handle is as polluted as possible, guarantees a largely clean camera ( 10 ). In addition, the camera ( 10 ) with the trunk closed for the persons located in the vicinity of the motor vehicle is not visible. However, the recessed installation position towards the outermost vehicle edge has the disadvantage that only a part of the rear space can be observed with it. Where the camera field of view ( 20 ) is limited either by the laterally protruding body parts or by the structure of the camera, so that so only a small detection area ( 30 ) is feasible.

In the 2 B is the side view of a known from the prior art attachment of a camera ( 10 ) is shown on the back of a motor vehicle. Here, the opposite of the camera ( 10 ) projecting bumpers ( 40 ) the camera field of view ( 20 ) and according to the 2a only a small area is detectable.

3a shows the perspective view of the integration of a catadioptric camera on the back of a motor vehicle. The mirror ( 4 ) of the catadioptric camera is here in the brake light ( 50 ) integrated. Thus, this embodiment also provides neutrality in terms of design requirements. In addition, this area is designed technically so that it contaminates relatively little. However, a significant advantage is the much larger coverage area ( 30 ). By the use of at least one mirror ( 4 ) with conical cross-section, it is possible a camera field of view ( 20 ) with an opening angle of more than 180 °. Where the camera field of view ( 20 ) is limited here only due to protruding body parts.

In 3b becomes the side view of the integration of a catadioptric camera ( 10 ) is shown on the back of a motor vehicle. The mirror ( 4 ) is in the brake light ( 50 ) integrated. Because of this opposite the in 2 B superior position can be a significantly larger field of view ( 20 ) realize. Here is the camera ( 10 ) at a protected position below the mirror ( 4 ) in the trunk. In an advantageous manner, the mirror ( 4 ) in the form of an additional pluggable component. The brake light ( 50 ) is therefore designed such that it comprises a receptacle for a plug-in mirror. Thus, for example, in all vehicles of a model variant the same brake light ( 50 ), the mirror ( 4 ) as well as the camera ( 10 ) can then be integrated later on request in the vehicle. In addition, arises in the manufacture of such, subsequently expandable with a mirror brake light ( 50 ) compared to a conventional brake light only a slightly higher cost. The invention thus also enables an economically advantageous retrofit solution. Thus, standard equipment manufactured with individual mirrors and cameras can be retrofitted cost-effectively.

1

image sensor

2

Optical-electrical converter

3

optics

4

mirror

5

Further optical means

10

camera

20

Camera field of view

30

detection range

40

bumper

50

Stoplight

Claims (8)

Catadioptric camera for a technical device, in particular a motor vehicle, in which at least one image sensor ( 1 ), consisting of an optical-electrical converter ( 2 ) and associated optics ( 3 ), Environmental information in the form of optical radiation when detected on at least one mirror ( 4 ), characterized in that the mirror ( 4 ) for reflecting the optical radiation separately from the image sensor ( 1 ) is attached directly to the outer skin of the technical device and / or directly attached to attachments of the technical device. Apparatus according to claim 1, characterized in that in the beam path between the image sensor ( 1 ) and mirrors ( 4 ) further optical means ( 5 ) are introduced. Device according to claim 2, characterized in that as a further optical means ( 5 ) An optical waveguide is introduced into the beam path. Device according to one of the preceding claims, characterized in that the mirror ( 4 ) has a conical cross section. Device according to one of the preceding claims, characterized in that the mirror ( 4 ) is an additional part of a lighting unit of the vehicle, in particular part of the lighting cover. Use of the device on a motor vehicle, wherein the mirror ( 4 ) is mounted in particular on the vehicle rear side in the region of the trunk handle. Use of the device on a motor vehicle, wherein the mirror ( 4 ) in the 3rd brake light (rear, center) is integrated. Use of the device on a work machine, wherein the mirror ( 4 ) is mounted in particular on a robot arm.