WO2009135539A1

WO2009135539A1 - Camera module with improved cooling design

Info

Publication number: WO2009135539A1
Application number: PCT/EP2008/065786
Authority: WO
Inventors: Ulrich Seger; Uwe Apel
Original assignee: Robert Bosch Gmbh
Priority date: 2008-05-09
Filing date: 2008-11-19
Publication date: 2009-11-12
Also published as: DE102008001675A1

Abstract

The invention relates to a camera module (110) for recording of image data, in particular for use in the motor vehicle industry. The camera module (110) comprises at least one image sensor chip (112), in particular a non-encapsulated image sensor chip (112). In addition, the camera module (110) comprises at least one Peltier element (128) with at least one cooling surface (138). The image sensor chip (112) is connected to the cooling surface (138) by at least one heat collector element (136), in particular at least one heat collector foil.

Description

description

title

Camera module with improved cooling concept

State of the art

The invention is based on known image acquisition and processing systems, as they can be used in particular in the automotive field. In the automotive sector, in particular camera systems for driver assistance functions as well as for the interior and / or exterior space monitoring of the motor vehicle are used. In many cases, cameras with integrated, complex computing power are to be designed for these purposes, since, for example, a transmission of a broadband video signal to a separate image processing computer in the vehicle environment is difficult to achieve. However, an integrated solution is again comparatively complicated, because in many cases due to high power losses of electronics used for image processing, the operating temperature of the image sensor is considerably increased compared to the situation in a camera with pure image acquisition functionality. However, the higher ambient temperature in turn leads to an increase in the dark current in the image sensor. For example, in conventional semiconductor materials, a leakage current at a pn junction can typically double every 8 to 10 K.

The compulsion to a compact design, which in particular in the automotive sector poor realizability of forced cooling for the camera, such as a camera behind the windshield, and the high power loss of the electronics for image processing require that the expected ambient temperature of the image sensor typically above 60 ⁰ C is located. This is hardly diminished by the fact that room conditions are typically created in the vehicle interior by air conditioning systems. As a result, dark currents increase considerably as explained above. Increasing these dark currents means that the cameras, for example, can no longer resolve the scene content in poorly lit areas in the image and that the available dynamic range is severely restricted, for example by more than a quarter. In fact, this leads to a limitation of the range of the field of view. There are therefore various types of cooling concepts known from the automotive industry, which are intended to solve the problem described above. Thus, for example, DE 103 19 176 A1 describes a device for cooling a camera in a motor vehicle, in which a camera module is connected via a thermally well-conductive connection with an externally placed on the housing heat sink. This heat sink is impinged by an air flow, which is taken from the air flow of the air conditioning and / or ventilation along the windshield. DE 103 19 176 A1 thus represents an example of a passive cooling concept for the automotive sector.

In addition to this purely passive cooling concept, active cooling concepts are also known. For example, DE 101 10 369 A1 describes an arrangement for cooling a sensor system installed in the headliner or at another temperature-sensitive location of a vehicle. In this case, a Peltier element or a similar cooling element with similar properties is used in close contact with the sensor system for cooling.

However, the use of known active cooling concepts, such as the Peltier cooling concept illustrated in DE 101 10 369 A1, is in practice associated with technical challenges in many cases. For example, DE 101 10 369 A1 uses commercially available Peltier elements. However, in many cases these Peltier elements are not adapted to the image sensors, so that these Peltier elements form, for example, condensation surfaces on which precipitation of moisture can occur. In addition, the heat coupling to the image sensors is not optimal in many cases due to the insufficient adaptation of the Peltier elements to the image sensors. The heat removal via the Peltier element is problematic in many cases, since, for example, the connection of the heat removal side of the Peltier element in DE 101 10 369 A1 can lead to a heating of the camera housing.

Disclosure of the invention

Therefore, a camera module for recording image data is proposed, which at least largely avoids the above-described disadvantages of known camera modules. The camera module is particularly suitable for use in the motor vehicle sector, for example for use in one of the driver assistance systems described above and / or for monitoring the interior and / or exterior of the motor vehicle. The proposed camera module allows an efficient lowering of the temperature only for an image sensor chip of the camera module, whereby a significant improvement of the system performance with a justifiable additional expenditure on components and operating performance becomes possible.

A "camera module" can be understood to mean an arbitrarily constructive device which comprises at least one image sensor chip for the acquisition of image data.An image sensor chip can be understood to mean virtually any component which is set up to receive optical information, in particular image data In particular, the image sensor chip may comprise at least one semiconductor component, in particular a photosensitive semiconductor chip, for example, a CCD and / or CMOS chip. In which the semiconductor material is at least substantially free and, for example, not received in a plastic housing (eg, encapsulated), this embodiment enables a particularly efficient cooling of the image sensor chip, since at least largely on insulating intermediate layer n between the image sensor chip and the cooling can be omitted. Alternatively or additionally, however, completely or partially encapsulated image sensor chips are also conceivable. In addition to the image sensor chip, the camera module may comprise further components, for example frames, housings, base plates or base plates, an evaluation and control electronics (for example, for the purpose of image processing described above), power supplies, interfaces, optical systems (especially lenses, lenses, screens, mirrors etc .) or similar.

The camera module furthermore comprises at least one Peltier element with at least one cooling surface (often referred to as "cold surface" in Peltier technology) .Peltier element can in principle be understood to mean any element which acts as an electric-thermal energy converter, in particular an element which taking advantage of the Peltier effect using electrical energy, a first surface, for example a surface of the element itself, cools (cooling surface) and a second surface, for example, again a surface of the element itself, warms (warming surface, in the Peltierchnik often as "Hot surface"). In this case, a temperature difference between the heating surface and the cooling surface is produced, which, for example, by the type of electrical energy used (eg, a current and / or voltage), the nature of the Peltier element, the environmental conditions or by similar effects or combinations of such effects. te can be influenced. The Peltier element may also be of modular design, for example, and comprise a plurality of individual Peltier elements which are, for example, cascade-shaped, zigzag-shaped or similarly coupled in order to act collectively as a Peltier element in the sense of the above definition. According to the invention, the image sensor chip is connected to the cooling surface of the Peltier element by at least one heat collecting element, in particular at least one heat collecting foil. This heat collecting element, which is connected as at least one intermediate layer between the image sensor chip and the Peltier element, can comprise at least one material with a good thermal conductivity. Preferably, materials are used which have a thermal conductivity of at least 1 W / (m * K) and preferably higher thermal conductivities, in particular of more than 100 to 200 W / (m * K). Materials with a high thermal conductivity are preferred, since otherwise the heat collecting element would cause an excessive temperature difference even at low power losses in the image sensor chip. Particular preference is given in principle to metals. For example, copper can be used, which has a thermal conductivity of 350 to 370 W / (m * K). Alternatively or additionally, for example, aluminum with a thermal conductivity of 220 W / (m * K) can be used. In principle, the use of plastics would be conceivable, in particular of filled plastics with a comparatively high thermal conductivity, conceivable. For example, thermoplastics and / or elastomers may be considered as the base material, for example silicone plastics. Plastics themselves generally have a thermal conductivity in the order of 1 W / (m * K). With appropriate fillings, such as metal and / or graphite fillings, this value can be increased even more. For example, copper-filled polyamides are available that achieve up to 10 W / (m * K) thermal conductivity. For the simple design of the heat collecting element so the cost advantage in the use of plastics is always to weigh against the significant disadvantage in terms of thermal resistance, so the metals are generally preferable. Also multi-layered structures can be used.

The at least one heat collecting element can in particular be designed as a cross-section-matching heat collecting element, wherein the heat collecting element has at least one first cross-sectional area to be assigned to the image sensor chip and at least one second cross-sectional area assigning the Peltier element. The first and the second cross-sectional area may be different. In this way, for example, a cross section of the image sensor chip can be adapted to a cross section of the Peltier element. For example, the first cross-sectional area may be designed to be larger than the second cross-sectional area. <br/><br/> The heat collecting element may in particular be configured mechanically such that the typically larger cross-section of this image sensor chip and on the Peltier element side on the side of the image sensor chip the typically smaller cross-section of the Peltier element are in each case contacted over the whole area and thus that a heat flow is applied to the smaller transverse concentration of the Peltier element is concentrated. The required heat transfer performance is achieved with the modern Peltier elements even with small areas. This results in a considerable advantage of the embodiment according to the invention, namely that a Peltier element that is significantly smaller than the image sensor and therefore cost-effective to produce can be used.

For example, the heat collecting element may have an at least partially trapezoidal cross section in at least one sectional plane. By way of example, this sectional plane may be a sectional plane perpendicular through the image sensor chip, the Peltier element and the heat collecting element, for example a sectional plane parallel to the edges of the image sensor chip and / or the Peltier element. Instead of a trapezoidal configuration, however, another embodiment can be selected, for example, a stepped configuration or a design with rounded edges, in which way also a cross-sectional change can be brought about. In addition to a cross-section-adapting region, the heat collecting element can also comprise regions of constant cross-section, for example cylindrical, columnar or disc-shaped regions.

The use of Peltier elements using heat collection elements allows an ideal coupling of the Peltier element to the back of the image sensor chip. For example, by using the trapezoidal heat collecting elements, it is possible in particular to ensure the most uniform possible temperature distribution on the image plane. By suitable geometric design of the heat collecting elements, a heat distribution in a semiconductor material of the image sensor chip, for example in silicon, and a distribution of power loss sources can additionally be taken into account.

In known systems, a disadvantage of the use of the Peltier elements in particular, as described above, in the poor adaptation of the Peltier elements to the BiId sensor chips. This adaptation can be greatly improved geometrically by the proposed use of the heat collecting element. A further improvement can be achieved by using very small Peltier elements, which have lateral dimensions in the micrometer to the millimeter range and which are thus adapted to the size of conventional semiconductor chips. Such very small Peltier elements open up the possibility of realizing cooling limited at least largely locally to the image sensor chip or even only to relevant regions of the image sensor chip. The (for example by means of wafer processes manufactured) micro-Peltier elements can on the chip size of the image sensor chip (for example, 6 x 7 mm ² ) and a power loss of a few hundred mW can be adapted and integrated in this way in the assembly and connection technology of the module low. Accordingly, it is proposed to adapt the Peltier element preferably in its lateral dimensions, ie in the dimensions in a plane parallel to the image plane of the image sensor chip, in at least one dimension to the image sensor chip. The lateral dimensions of the Peltier element preferably exceed the respectively associated dimensions of the image sensor chip by not more than 100%, preferably by not more than 50% and particularly preferably by not more than 10%. For example, it is possible to avoid unnecessary cooling surfaces, at which condensation can occur, and it is possible to realize energetically particularly favorable cooling.

For example, it can be calculated that with an assumed power loss of the image sensor chip of 160 mW and a temperature in the camera module of about 60 ⁰ C, the temperature of the image sensor chip can be lowered by 20 K, with an additional cooling power of less than 300 mW. Commercially available Peltier elements have an efficiency coefficient of better than 0.5 at this operating point, with a further development of this technology and a further increase in the efficiency can be expected in the near future. Thus, with a relative to the total power consumption of the camera module preferably low additional power a significant reduction in the dark currents in the image sensor chip can be realized. The associated increase in visibility, especially in twilight and at night, represents a significant technical advantage over conventional camera modules.

The cooling capacity used can be implemented with the maximum efficiency in lowering the temperature. This is due to the fact that in the structure described in which the Peltier element only has to cool the heat collecting element and the image sensor chip, only the low mass of the image sensor chip and the heat collecting element has to be cooled. Therefore, the structure is due to the principle of a low thermal short circuit. In addition, only the low power dissipation of, for example, carried out in CMOS technology, image sensor chip must be dissipated via the Peltier element. Other power losses, such as power losses of electronic components for image processing can remain uncooled or can be cooled separately.

The direct chip cooling of the image sensor chip, which in the present case can only take place via the heat collecting element, in contrast to conventional techniques in which complete, in particular encapsulated image sensor modules are cooled, is further promoted by current developments in image sensor technology. For example, further developments in the assembly and connection technology, which are reflected in the image sensor chips, in particular the possibility of constructions with even improved boundary conditions for the temperature reduction in the image sensor chip with minimal additional energy expenditure. Thus, for example, the layer thickness of the semiconductor material, for example silicon, is currently reduced to layer thicknesses in the range of 30 to 60 μm. The thermal mass and the thermal resistance to the Peltier cooler is again significantly reduced, and a faster response to the introduced cooling capacity can be achieved. In addition, the wire bonds, which represent a significant contribution to the thermal short circuit, can be replaced by so-called through-silicon vias (TSVs). Thus, the electrical connection via a method that is comparable to the soldering Ball Grid Arrays (BGAs) on thin flex foil circuit boards, designed.

Further improvements of the proposed camera module relate in particular to the storage or reception of the Peltier element in the camera module. As described above, the camera module may in particular comprise a housing, which may, for example, comprise at least one base plate, that is to say a plate or a housing part facing away from an imaging optics of the camera module. Instead of a single base plate, however, it is also possible to provide a plurality of base plates or also non-planar housing parts which are arranged on the side of the camera housing facing away from the image-sensitive side of the image sensor chip and thus can likewise be referred to as a base plate. In contrast to known camera modules, such as the camera module known from DE 101 10 369 A1, it is particularly preferred according to the invention to decouple the spacer element thermally from the housing or the bottom plate of the housing. The housing is exposed in many cases strong thermal loads or fluctuations, which are caused for example in the front region of the motor vehicle by sunlight, or which can also be caused by an integrated in the housing evaluation electronics. In order to achieve an at least substantial thermal decoupling of the Peltier element from the housing, for example, the Peltier element can be insulated from the base plate by means of at least one thermally insulating frame. A "frame" can be understood to mean any holder which receives the Peltier element and separates this Peltier element from the base plate and / or the rest of the housing, however, a peripheral thermal frame, for example a frame let into an opening in the base plate, is particularly preferred. Accordingly, this frame or a corresponding insulating enclosure can be configured in such a way that a warming surface of the Peltier element is arranged on an outer side of the camera module, that is to say for example on a side facing the interior of the motor vehicle, where it is included. For example, by a draft (for example, a fan for ventilation of the windshield of the motor vehicle) can be cooled.

In order to additionally improve the heat removal from the warming side of the Peltier element, at least one heat dissipation element can furthermore be provided. This heat-dissipating element can in particular be designed in accordance with the heat-collecting element described above with regard to the preferred materials. In particular, the heat dissipation element may in turn comprise at least one heat dissipation foil. The heat dissipation element should be thermally separated from the bottom plate and should at least partially penetrate the bottom plate. In this way, heat of the warming surface of the Peltier element can be transported away on an outer side of the camera module. For example, the heat-dissipating element can again be configured as a cross-section-matching heat-dissipating element and can have at least one first cross-sectional area attributed to the Peltier element and at least one second cross-sectional area facing the outer side of the camera module, the first and second cross-sectional areas preferably being different. In turn, the heat dissipation element may at least partially and in at least one sectional plane have a trapezoidal cross-section, for example a trapezoidal cross-section with a cross-sectional area which widens outwards. Alternatively or additionally, however, it is also possible to use shapes other than a trapezoidal shape, for example a stepped shape, a shape with rounded side surfaces or the like. By means of the cross-section-matching element, which can act as a heat spreader, and which is mounted on the warm side of the Peltier element, the waste heat can for example be led to a separate heat exchanger, or it can be as large as possible in another way Surface are provided for dissipating the heat from the warm side of the Peltier element. In this way, the heat can preferably not be fed back directly to the housing elements of the camera module, so that the thermal short circuit can be reduced.

If the layer thickness of the Peltier element, which may be configured in particular as a micro-Peltier element, is less than the layer thickness of the bottom plate or of the housing in the region in which the heat is to be dissipated, the heat dissipation element in this area can be a non-cross section adaptive Section can be extended, which can also be referred to as a transfer section. This transfer section can at least partially penetrate the bottom plate or the housing in the region of the heat removal. For example, the transfer section can be adapted to the cross-section of the Peltier element from its cross-sectional shapes and thus accommodate the (for example rectangular) contour of the Peltier element. In which subsequent region of the heat dissipation element, in which this causes the Querschnittsver- change, and which is arranged for example on the outside of the housing, then the best possible removal of the heat can be effected. The transfer section then takes over the thermally decoupled breakthrough of the heat dissipation element through the bottom plate. The transfer section and / or the entire heat-dissipating element, as well as optionally the heat-collecting element, in whole or in part in addition to the housing, for example the bottom plate, be thermally insulated, for example by using at least one additional insulation element, for example, again a frame. The heat dissipation element can be connected to at least one cooling element on an outer side of the camera module. This cooling element may comprise, for example, a heat exchanger, a heat sink, in particular a ribbed heat sink, liquid cooling, air cooling, in particular a fan, or similar cooling elements or combinations of cooling elements.

Another way to minimize the coupling of heat through parasitic paths can be achieved by filling the camera module with a protective gas, which has a lower convection slope and / or a lower heat transfer coefficient compared to air. As an example of such protective gases can be called argon or krypton. The protective gas also has the advantage that the risk of fogging during cooling is reduced. As an alternative or in addition to exposure to protective gas, it would also be possible to apply a vacuum (vacuum). Such a vacuum Verkap rating of the cooled image sensor chip could cause a further reduction of thermal bridges over which the thermal short circuit takes place.

A further preferred embodiment of the camera module relates to the control of the cooling means of the Peltier element. This activation can also be realized without the above-described mechanical-thermal configurations of the camera module, that is, for example, in camera modules which merely have an image sensor chip with a peripheral cooling, without a heat collecting element. In the proposed cooling concept, however, the improvement of the control can be used particularly favorably. Thus, the invention proposes to drive the Peltier element preferably so that a loss line only occurs when the temperature of the image sensor chip exceeds a limit, which leads to an unacceptable degradation of image quality. In this way, optimal use can be achieved while minimizing energy consumption. Accordingly, it is proposed that the camera module has at least one controller. This control may, for example, comprise an electronic control, for example one or more electronic components. For example, the controller can control a microcomputer, for example a microcontroller, with a central controller. data processing unit, one or more volatile and / or non-volatile memories, interfaces or similar, usually contained in data processing equipment components. The controller can, for example, programmatically, then be set up to determine a cooling demand and to control the Peltier element according to the determined cooling demand. For example, the control, as shown above, take place according to a pure threshold value method, that is, a control of the Peltier element only when a certain threshold of the image quality is exceeded. Alternatively or additionally, however, it is also possible for a continuous and / or stepped or other type of activation to be carried out in accordance with the cooling requirement.

To determine the cooling requirement for driving the Peltier element, it is particularly preferred to use a noise-equivalent signal. Such a noise equivalent signal is a signal which directly or indirectly reflects image quality in terms of image noise. For example, the image noise at one, several or all pixels of the image sensor chip can be detected and used for control. This can result in stable image quality over a wide range of operating temperature. For subsequent image processing, stabilization can positively impact higher availability. In addition, the controlled use of the Peltier element makes it possible to prevent the image sensor chip from becoming the condensing water condensation surface during operation near the dew point, or to respond to incipient condensation by reducing the cooling capacity.

Brief description of the drawings

Embodiments of the invention are illustrated in the drawings and explained in more detail in the following description.

Show it

Figure IA to IC different sectional views of a first embodiment of a camera module according to the invention with a Wärmesammelele- element;

FIGS. 2A to 2C show various sectional views of a second exemplary embodiment of a camera module according to the invention with a trapezoidal shape

Heat collection element; and 3 shows a sectional view similar to FIG. 2C of a third exemplary embodiment of a camera module with a trapezoidal heat collecting element and a trapezoidal heat dissipation element.

embodiments

In the figures IA to IC various highly schematic sectional views of a first exemplary embodiment of a camera module 110 are shown. In this case, FIG. 1A shows a top view, in plan view, of an image sensor chip 112, FIG. 1B shows a sectional view along the section line A-A 'in FIG. 1A, and FIG. 1C shows a sectional view along the section line B-B' in FIG. In the following reference is made to all these representations, since these are explained simultaneously. The camera module 110 comprises a housing 114, with a bottom plate 116 and a lens barrel 118. In the lens barrel 118, a lens 122 is inserted by means of a lens mount 120, which is not shown in the illustration according to FIG IA. This lens 122 usually comprises a plurality of lens elements 124, as well as optionally further elements, such as diaphragms or the like.

The bottom plate 116, like the rest of the housing 114, for example, wholly or partially made of plastic or, preferably, be designed as a metallic base plate. On and / or in this bottom plate 116, a flex foil 126 is applied, that is to say a flexible printed circuit board which, for example, has conductor tracks for electrical contacting of the image sensor chip 112 and / or a Peltier element 128. In this embodiment, a Peltier element 128 and the image sensor chip 112 are mounted on this flex foil 126. The electrical contacting can take place via bonds 130 for the image sensor chip 112 (see FIG. 1C) and via bonds 128 designed for stronger currents for the Peltier element 128. The bonds 130, 132 may be set, for example, by a conventional wire bonding method. The bonds 130 for the image sensor chip 112 may, for example, be arranged on two edges of the image sensor chip 112, whereas the Peltier element 128 may be contacted via the bonds 132, for example only on one end side.

To accommodate the lens barrel 118, the housing 114 may further include a ring portion 134 (see FIG. 1A). On this ring section 134, the assembly of the objective tube 118 with the objective 122 inserted therein can take place. The flex foil 126 may be passed under the ring portion 134, for example, within a recess in which the entire flex foil 126 may be received and retained. As can be seen for example from FIG. 1A, the Peltier element 128 is well adapted to the image sensor chip 112 in terms of its lateral dimensions, so that, for example, the edge lengths of the Peltier element 128 do not exceed the edge lengths of the image sensor chip 112 by more than a factor of two. In order to collect the waste heat of the image sensor chip 112, a heat collecting element 136 is provided between the image sensor chip 112 and the Peltier element 128 according to the invention. This heat collecting element 136 may be configured, for example, as a heat conducting foil, for example in the form of a silicone heat conducting foil. Heat conductivities of 2 W / mK or more are particularly preferably achieved. The heat-conducting foil of the heat-collecting element 136 may have, for example, a thickness of approximately 1 mm. The heat collection element 136 collects the waste heat of the image sensor chip 112 before it can heat, for example by radiation, remaining components of the camera module 114 and passes this waste heat efficiently to the Peltier element 128 on. The Peltier element 128, which has a cooling surface 138 and a warming surface 140 (which may be predetermined by the sound of the Peltier element 128), then dissipates the waste heat via its heating surface 140 to the base plate 116 of the camera module 110.

FIGS. 2A to 2C show a second exemplary embodiment of a camera module 110 according to the invention, in sectional representations which correspond to the sectional views of FIGS. 1A to 1C. In this respect, reference may be made to the above description of the figures IA to IC for the design of the common elements. In the exemplary embodiment illustrated in FIGS. 2A to 2C, the adaptation of a Peltier element 128 to the lateral dimensions of the image sensor chip 112 is further improved. By adapting the Peltier element 128 to the size of the image sensor chip 112, the cooling efficiency can be improved by concentrating the cooling solely on the image sensor chip 112, without the image sensor chip 112 having to be designed to be larger. Again, the housing 114 of the camera module 110 has a bottom plate 116, such as a metallic bottom plate or substrate plate. In turn, the flex foil 126 with the conductor tracks for the electrical connection of the image sensor chip 112 and the chip-shaped Peltier element 128 is mounted on this bottom plate 116 or in a recess of this bottom plate 116. The bonds 130 and 132 for the image sensor chip 112 and the Peltier element 128 may be arranged analogously to the embodiment in FIG. 1A.

In turn, a heat collecting element 136 is also provided between the Peltier element 128 and the image sensor chip 112. In the illustrated embodiment, however, the heat collection element 136 is configured as a cross-sectional matching heat collection element and has a first cross-sectional area 142 that assigns the image sensor chip 112, and a second cross-sectional area 144 which assigns the Peltier element 128. As can be seen from the consideration of FIGS. 2B and 2C, the second cross-sectional area 144 is smaller than the first cross-sectional area 142, so that in the sectional positions shown in FIGS. 2B and 2C the heat-collecting element 136 has a trapezoidal cross-section. While the first cross-sectional area 142 substantially corresponds to or is only slightly smaller than the cross-sectional area of the image sensor chip 112, the second cross-sectional area 144 is adapted to the lateral dimensions of the Peltier element 128, at least in the cross-sectional direction BB 'in FIG. The heat collecting element 136 thus acts in such a way that it collects the heat exiting at the bottom of the image sensor chip 112 and transmits it concentrated to the Peltier element 128.

Finally, FIG. 3 shows, in a sectional view analogous to FIG. 2C, a third exemplary embodiment of a camera module according to the invention in which the idea of a trapezoidal heat collecting element 136 shown in FIGS. 2A to 2C is continued. In this case, analogously to the embodiment in FIG. 2C, for example, the heat collecting element 136 is adapted to the image sensor chip 112 or the Peltier element 128 from its cross-sectional areas 142, 144. In contrast to the illustration according to FIGS. 2A to 2C, however, no heat is transferred to the bottom plate 116 of the housing 114 on the warming surface 140 of the peltier element 128, but the Peltier element 128 is thermally insulated from the bottom plate 116. For this purpose, the camera module 110 has a thermally insulating frame 146 within which the Peltier element 128 is passed through the bottom plate 116. This frame 146 may for example consist of a flexible material, which facilitates assembly. As an example, an elastomer or rubber could be used as the material, for example an ethylene-propylene-diene rubber (EPDM).

On the warming surface 140 of the Peltier element 128, a heat dissipation element 148 is provided, which connects the Peltier element 128 with a ribbed heat sink 150 outside the housing 114 of the camera module 110. In this case, the heat dissipation element 148, which basically may consist of the same material as the heat accumulation element 136, in turn has a trapezoidal design and has a first cross-sectional area 152 and a second cross-sectional area 154. While the first cross-sectional area 152 facing the Peltier element 128 is again adapted to the lateral dimensions of the spacer element 128, the second cross-sectional area 154, which assigns the heat sink 150, is made larger and, for example, adapted to the lateral dimensions of the heat sink 150. In this way, in the form of a "heat spreader", the heat of the warming surface 140 of the Peltier element 128 can be effectively dissipated via the heat sink. element 148 and the heat sink 150 are discharged to the ambient air. It should be noted that in the exemplary embodiment illustrated in FIG. 3, the Peltier element 128 itself is guided through the opening within the base plate 116. However, this is not mandatory. Thus, for example, the heat dissipation element 148, in addition to the trapezoidal profile shown in FIG. 3, can have a region with a substantially uniform cross section, which is led through the bottom plate 116. In this area, for example, the Peltier element 128 can then be placed.

In the exemplary embodiment shown in FIG. 3, the contacting can again take place via a separate printed circuit board and / or via a flex foil 126. As in the previous exemplary embodiments, additional components, for example electronic components, may also be accommodated within the housing 114, which may also be arranged in whole or in part likewise on the flex foil 126 and / or another printed circuit board. In addition to the housing 114 illustrated in the figures, the camera module 110 can comprise further housing components, for example an enclosure enclosing the entire arrangement shown in the figures. Other embodiments are conceivable.

Claims

claims

1. Camera module (110) for receiving image data, in particular for use in the automotive sector, comprising at least one image sensor chip (112), in particular a non-encapsulated image sensor chip (112), further comprising at least one peier animal element (128) with at least one cooling Surface (138), wherein the image sensor chip (112) with the cooling surface (138) by at least one heat collecting element (136), in particular at least one heat collecting film, is connected.

2. The camera module (110) according to the preceding claim, wherein the heat collecting element (136) is configured as a cross-section matching heat collecting element (136), wherein the heat collecting element (136) at least one, the image sensor chip (112) facing first cross-sectional area (142) and at least a second cross-sectional area (144) facing the Peltier element (128), the first and second cross-sectional areas being different.

3. Camera module (110) according to the preceding claim, wherein the heat collecting element (136) at least partially and in at least one sectional plane has a trapezoidal cross-section.

4. The camera module (110) according to any one of the preceding claims, wherein the Peltier element (128) in its lateral dimensions of the lateral dimensions of the image sensor chip (112) in at least one dimension, preferably in both dimensions, by not more than 100%, preferably not more than 50%, and more preferably not more than 10%.

5. The camera module according to claim 1, wherein the camera module comprises at least one base plate, wherein the Peltier element is isolated from the base plate by means of at least one thermally insulating frame. is received in particular in the bottom plate (116).

6. Camera module (110) according to one of the preceding claims, wherein the camera module (110) comprises at least one bottom plate (116), wherein the Peltier element (128) is connected to at least one heat dissipation element (148), in particular at least one heat dissipation foil, wherein the Heat dissipation element (148) against the

Bottom plate (116) is thermally separated, wherein the heat dissipation element (148) at least partially penetrates the bottom plate (116) and is adapted to heat a warming surface of the Peltier element (128) on an outer side of the camera module (110) to transport.

7. The camera module (110) according to the preceding claim, wherein the Wärmeableitele- element (148) is designed as a cross-section matching Wärmeableitelement (148), wherein the Wärmeableitelement (148) at least a first, the Peltier element (128) assigning cross-sectional area (152) and at least a second, the outside of the camera module (110) assigning cross-sectional area (154), wherein the first and the second cross-sectional area are different.

8. Camera module (110) according to the preceding claim, wherein the heat dissipation element (148) at least partially and in at least one sectional plane has a trapezoidal cross-section.

9. The camera module (110) according to one of the two preceding claims, wherein the heat dissipation element (148) further comprises a transfer section, wherein the transfer section is configured substantially without cross-sectional change and at least partially penetrates the bottom plate (116).

10. The camera module (110) according to claim 6, wherein the heat dissipation element (148) is connected to at least one cooling element (150) on an outer side of the camera module (110), in particular to at least one of the following cooling elements (150): a heat exchanger; a heat sink (150), in particular a corrugated heat sink; a liquid cooling; an air cooling, in particular a fan.

11. Camera module (110) according to one of the preceding claims, wherein at least one of the image sensor chip (112) and / or the Peltier element (128) receiving the interior of the camera module (110) is filled with a protective gas, in particular argon and / or krypton, and / / or is subjected to a vacuum.

12. Camera module (110) according to one of the preceding embodiments, wherein the image sensor chip (112), the Peltier element (128) and the heat collecting element (136) at least partially on a flexible conductor foil (126) are arranged.

13. The camera module (110) according to one of the preceding claims, further comprising at least one controller, wherein the controller is set to a cooling requirement to determine and to control the Peltier element (128) according to the determined cooling demand.

14. The camera module (110) according to the preceding claim, wherein the controller is set to the cooling demand from a noise equivalent signal, in particular a

Noise of the image sensor chip (112) to be detected.