WO2018065168A1

WO2018065168A1 - Method for the contactless sensing of two-dimensional temperature information, and thermal imaging camera

Info

Publication number: WO2018065168A1
Application number: PCT/EP2017/072604
Authority: WO
Inventors: Michael Frank; Daniel Marquardt; Axel Rumberg; Mike Uhlig; Patrick Meyer; Tatiana Babkina
Original assignee: Robert Bosch Gmbh
Priority date: 2016-10-06
Filing date: 2017-09-08
Publication date: 2018-04-12
Also published as: DE102016219388A1

Abstract

The invention proposes a handheld thermal imaging camera (10) for the contactless sensing of two-dimensional temperature information (12) of a scene (14), which comprises a housing (16) having at least one infrared detector array (48), said infrared detector array (48) consisting of a plurality of infrared-radiation-sensitive pixels (56). According to the invention, a projection device (34, 34a) is arranged in or on the housing (16) of the thermal imaging camera (10), the purpose of which is to convert two-dimensional temperature information (12) sensed by the infrared detector array (48) into a projectable image (36) and to project the projectable image (36) onto the scene (14). The invention further proposes a method for the contactless sensing of two-dimensional temperature information (12) of a scene (14).

Description

description

title

Method for non-contact determination of a two-dimensional temperature information and thermal imaging camera

The invention relates to a thermal imaging camera for non-contact determination of a two-dimensional temperature information of a scene, in particular for non-contact determination of a thermal image of a scene, and a method for non-contact determination of a two-dimensional temperature information of a scene.

State of the art

Devices and methods for the non-contact determination of a two-dimensional temperature information of a scene are known from the prior art and are used in a variety of applications, for example for the safety inspection of electrical circuits, for troubleshooting in machine processes or for the identification of insufficient heat insulation in the context of thermal and / or cold insulation.

Infrared measuring systems have the advantage of non-contact and rapid measuring over conventional temperature measuring devices and can be used in particular when areas to be measured are difficult or impossible to access. The temperature measurement by means of an infrared-sensitive thermometer is based on detection of thermal radiation, ie infrared radiation in a wavelength range between in particular 3 μηι and 50 μηι, which is emitted by each object depending on its temperature, in particular its surface temperature, with different intensity. Out a contactless measured intensity of the emitted heat radiation, a surface temperature of the emitting body or an emitting scenery can be determined. Thermal imaging cameras for contact-free determination of a two-dimensional temperature information of a scene typically have an infrared-sensitive image sensor, a lens system and a screen and, like a camera operating in the visual spectral range, allow an object to be examined in the infrared region of the radiation spectrum and displayed on the screen as a two-dimensional image. often output color-coded image of the object. DE 10 2014 226 342 A1 describes such a thermal imaging camera.

Disclosure of the invention

The invention is based on a hand-held thermal imaging camera for non-contact determination of a two-dimensional temperature information of a scene, in particular for non-contact determination of a thermal image of a scene. The thermal imaging camera has a housing with at least one infrared detector array, wherein the infrared detector array consists of a plurality of infrared radiation sensitive pixels. According to the invention, a projection device is arranged in or on the housing, which is provided for converting a two-dimensional temperature information determined by means of the infrared detector array into a projectable image and for projecting the projectable image onto the scene.

"Thermal Imaging Camera" refers to a device for non-contact measurement of a two-dimensional temperature information of a scene by outputting at least one information relating to the two-dimensional temperature information, for example by outputting one or more temperature indications, advantageously two or more temperature measurements, a temperature distribution or the like two-dimensional temperature information in the form of a composite of a plurality of spatially resolved and / or spatial angle resolved temperature readings thermal image exist. A "hand-held" thermal imaging camera is to be understood in particular as meaning that the thermal imaging camera can only be transported by hand, especially with one hand, without the aid of a transport machine The mass of the hand-held thermal imaging camera is in particular less than 5 kg, advantageously less than 3 kg and particularly advantageously less than 1 kg the thermal imaging camera can be guided by a user.

The hand-held thermal imaging camera in one embodiment has a housing that accommodates at least the essential functional components of the thermal imaging camera. The thermal imaging camera preferably consists of only one housing, which forms the main body of the thermal imaging camera. In particular, the housing accommodates at least one control device, an infrared detector array, an input and / or output device, in particular a display device, a power supply device and an evaluation device and the projection device. In particular, the components are housed in their total volume to more than 50%, preferably more than 75% and particularly preferably 100% in the housing of the thermal imaging camera. In this way, a particularly compact thermal imaging camera which can easily be guided by one user with one hand can be realized. Furthermore, the components of the thermal imaging camera can be advantageously protected in this way by a housing of the thermal imager from damage and environmental influences, for example against the ingress of moisture and dust. It should be noted that at least parts of the essential functional components can also be arranged outside the housing of the thermal imaging camera on the housing. For example, in particular the projection device can also be arranged on the outside of the housing of the thermal imaging camera. The thermal imaging camera is set up to detect non-contact determination of a two-dimensional temperature information of a scene, in particular for non-contact determination of a thermal image of a scene, in a solid angle region emitted by the scene infrared radiation. It should be pointed out that within the scope of this document the term "infrared radiation" is synonymous with heat radiation. <br/><br/> [0002] The spatial angle range - also referred to as "measuring range" - is understood to mean a geometrically, locally limited area which comprises at least a section of the scene to be examined includes, the infrared radiation leaves the object or objects of the scenery in the direction of the thermal imaging camera and is at least partially detected by the thermal imaging camera. Typically, the solid angle range is defined by the inlet opening of the thermal imaging camera or by the optical properties of the thermal imaging camera (for example, by zoom, angle coverage, opening angle, etc.).

For measuring infrared radiation, the thermal imaging camera has at least one infrared detector array and an evaluation device. The infrared detector array has a plurality of infrared radiation sensitive pixels. The infrared detector array detects infrared radiation emitted in the solid angle region and projected on its surface, and generates a detection signal based on the detected intensity of incident infrared radiation. The infrared detector array has a two-dimensional detection surface on a surface facing the scene, on which the plurality of infrared radiation-sensitive pixels is arranged. Each of the pixels of the infrared detector array can - assuming illumination by means of infrared radiation - determine image information and generate a detection signal therefrom. The detection signal provided by each pixel can then be used to determine temperature information. In particular, the detection signal of each pixel can be forwarded to the evaluation device of the thermal imaging camera. From the evaluation device, the detection signal can be evaluated individually and / or in combination with detection signals of other pixels.

Each pixel of the infrared detector array is an infrared radiation sensitive element and is intended to receive infrared radiation. in particular from the middle infrared range in the wavelength range between 3 μm and 50 μm, and to convert it into a detection signal, in particular an electrical detection signal. Typically, the detection signals generated by such radiation-sensitive elements are dependent on an infrared radiation intensity incident on the respective element. Examples of such elements which are sensitive to infrared radiation include photodiodes, bolometers, pyroelectric sensors, P / N diodes, PIN diodes, avalanche photo diodes (APD), (modulated) CCD chips and CMOS pixels, but others, For example, silicon sensors, indium gallium arsenide sensors, lead sulfide sensors, indium antimony sensors, cadmium mercury telluride sensors, gallium arsenide quantum well sensors, cadmium mercury telluride sensors, which appear useful to a person skilled in the art or the like based, infrared radiation sensitive elements are understood.

In one embodiment of the thermal imaging camera, the plurality of pixels are arrayed on the scene-facing surface of the infrared detector array. The number of pixels is for example 80 * 80 pixels, preferably 360x240 pixels, particularly preferably 640> <480 pixels. The number of pixels defines the resolution of the thermal imager, i. in particular the resolution of a two-dimensional temperature information measured by means of the thermal imaging camera. Due to the matrix-like arrangement, a particularly homogeneous and, in particular, complete detection of infrared radiation can take place from the solid angle range, since the infrared detector array is provided homogeneously and in particular without gaps with pixels.

Each of the pixels of the infrared detector array can be connected to the evaluation device directly or indirectly via further intermediate components by signal technology. In particular, an indirect signaling connection of the pixels with the evaluation device can also be realized via switching elements, for example multiplexers or other selection circuits, which are designed to selectively transmit detection signals of several pixels. In this way it can be achieved, in particular, that detection signals of individual pixels or of a group of pixels, independently of detection signals of other pixels, are applied to the Evaluation device forwarded and can be evaluated by this.

The term "provided" is to be understood in the following to mean specifically "programmed", "designed", "designed" and / or "equipped." The term "provided" for an object for a specific function should in particular be understood to mean that the object fulfills and / or carries out this specific function in at least one application and / or operating state or is designed to perform the function.

The "evaluation device" of the thermal imager should be understood to mean a device which has at least one information input for accepting detection signals, an information processing unit for processing, in particular evaluation of the assumed detection signals, and an information output for passing on the processed and / or evaluated detection signals and / or evaluation information Advantageously, the evaluation device has components that comprise at least one processor, a memory and an operating program with evaluation and calculation routines, In particular, the electronic components of the evaluation device can be arranged on a printed circuit board or printed circuit board, preferably on a common board with a control device of the thermal imaging camera Furthermore, the control device and the evaluation device can also be embodied as a single component, for example in Fo rm of a microcontroller. The evaluation device is provided for receiving and evaluating detection signals generated by the infrared detector array, in particular from the pixels that can be signaled by the evaluation device, and for evaluating the two-dimensional temperature information of the scene based on detection signals of at least one plurality of illuminated pixels of the infrared detector array. The evaluation device is preferably provided based on detection signals of at least one plurality of illuminated pixels, an evaluation of one or more temperature measurement values, in particular also averaged temperature measurement values, particularly preferably a thermal image. In this way, the evaluation device serves to determine a two-dimensional temperature information, in particular a thermal image, from measured infrared data. red radiation. The evaluated two-dimensional temperature information, in particular the thermal image, can be provided by the evaluation device for further processing and / or output to a user of the thermal imaging camera by means of an output device, in particular by means of the projection device, and / or an external device by means of a data communication interface.

Furthermore, in one embodiment, the thermal imaging camera can also have an optical system, in particular an imaging optical system for imaging infrared radiation from the solid angle region onto the infrared detector array. Such optics is intended to project from the solid angle range emitted infrared radiation, preferably in the middle infrared spectrum in the wavelength range between 3 μηι and 50 μηι, on the surface of the view of the scenery behind the optics arranged infrared detector array or focus. The optics may in particular have infrared components which guide, conduct, bundle and / or otherwise influence the spatial propagation of optical components, for example lenses, mirrors or the like. Further, in one embodiment, optics may be provided to adjust a magnitude of the solid angle range, i. to set a size of the measuring range of the thermal imaging camera changeable using the optics, in particular steplessly to set "zoomable".

In one embodiment of the thermal imaging camera, the thermal imaging camera has a screen by means of which the two-dimensional temperature information, in particular the thermal image, can be displayed and thus output to a user of the thermal imaging camera.

According to the invention, a projection device is arranged in or on the housing of the thermal imaging camera, which is provided for converting a two-dimensional temperature information determined by the infrared detector array into a projectable image and which is provided for projecting the projectable image onto the scene. The projection device is used for outputting the two-dimensional temperature information, in particular the thermal image, by generating a projection on the scene, in particular on a projection surface of the scene or a projection surface in a predetermined spatial profile. graced picture. The projected image preferably comprises the determined two-dimensional temperature information, in particular the determined thermal image.

The projection device is designed to project the image onto the scene. For this purpose, the projection device may have a structure which allows both a simultaneous planar projection, for example using an LC display or a micromirror field, as well as a stroboscopic projection using other illumination sources, such as a filament lamp, an arc lamp and / or an LED. In one embodiment, the projectable image serves to augment that of the

Scenery, especially from the projection screen of the scenery, defined working environment. Such an augmentation can be used, for example, to efficiently find cold bridges in a house facade to be examined.

In one embodiment of the hand-held thermal imaging camera, the projection device has at least one light or video projector and / or one laser projector. The light or video projector and / or the laser projector are used to project the projected image converted by the projection device onto the scene, for example onto an examined wall. In particular, in one embodiment, the thermal imager can also have a plurality of video projectors designed for simultaneous planar projection, in particular one or more projectors. Furthermore, a laser-based projection device can also be used, which can be realized with different deflection principles, for example with rotary prisms, galvanometer mirrors and / or micromirrors.

In one embodiment of the hand-held thermal imager, the projection device projects substantially into the same solid angle from which the thermal imager measures infrared radiation. In particular, the "projection in the same solid angle" also includes the projection in the same spatial direction, from which the thermal imager measures infrared radiation In this way, a particularly simple embodiment of the thermal imager can be specified, which still provide an accurate, distortion-free projection of the projected In particular, the currently investigated Immediately superimpose the scene with an evaluated thermal image by projection. Advantageous is the result of the projection, in particular the quality and accuracy of the conformity of the projected image with the examined scene, regardless of a current position and / or orientation of the thermal imaging camera. A predistortion device for predistorting the image to be projected as a function of the instantaneous position and / or orientation of the thermal imaging camera can thus be dispensed with.

The projection device is furthermore provided for converting the two-dimensional temperature information determined by means of the infrared detector array into a projectable image. In order to carry out relevant conversion steps, in one embodiment of the thermal imaging camera the projection device may in particular comprise an image-generating device, a computing unit or an evaluation unit. In an alternative embodiment, the relevant conversion steps can also be carried out using the evaluation device of the thermal imaging camera. The relevant conversion steps include at least the generation of image data based on the determined two-dimensional temperature information.

In one embodiment of the hand-held thermal imaging camera, the projection device is provided to determine from the two-dimensional temperature information projectable contours, in particular isotherms, and to project them. The projection device can advantageously evaluate the two-dimensional temperature information in such a way that a projectable image is formed in which lines connect points (locations) of the same temperature, in particular lines connect points (locations) of identical, discretely spaced defined temperatures (for example in 10 ° C. steps) , In this way, an easily interpretable projectable image can be provided, which further does not require a particularly elaborate projection device. In particular, a projectible image can be provided which can be projected onto the scene by projecting only one color, for example using red laser light. An elaborate color video projector can thus be dispensed with. In one embodiment of the hand-held thermal imaging camera, the projection device is provided for using different light intensities, in particular different laser intensities, and / or different colors and / or different gray levels to highlight different areas of the projected two-dimensional temperature information, in particular areas of different temperature, and / or highlight. In particular, the projection device is intended to assign different regions of the projected two-dimensional temperature information, in particular regions of different temperature, different light intensities, in particular different laser intensities, and / or different colors and / or different gray levels. In this way, it is possible to realize a scene augmentation that is particularly intuitive for a user of the thermal imaging camera. For example, areas of different temperature with different light intensities or laser intensity can be illuminated, so that a kind of relief effect arises, by means of which

Detect geometry of regions of different temperature in an intuitive way. Alternatively or additionally, different colors and / or gray levels may be used in the projection to identify different areas of the projected two-dimensional temperature information. In one embodiment, it is conceivable to realize the projected image in the form of a "heat map", ie as a two-dimensional diagram whose position-dependent values are represented as colors, so that a large amount of data and in particular marked values within this data volume can be detected intuitively and quickly ,

In one embodiment of the hand-held thermal imaging camera, the projection device is provided to mark and / or emphasize areas with temperatures above a defined threshold and / or areas with temperatures below a defined threshold in the projection.

In this way, an amount of data output by means of projection to a user of the thermal imaging camera can advantageously be reduced so that only certain areas of a specific, for example, previously defined, temperature in the projected image on the scene can be removed. For example, such cold bridges can be marked or highlighted and thus also especially quickly recognize and find. In one embodiment, highlighting or highlighting regions having temperatures above a defined threshold and / or temperatures below a defined threshold may be accomplished using a laser spot emitted at corresponding locations in the scene.

In one embodiment of the hand-held thermal imaging camera, the thermal imaging camera has a data communication interface intended to provide at least one additional piece of information that is projected onto the scene superimposed on the projectable image.

The data communication interface should in particular be understood to mean a device which is intended to accept at least one piece of information from a user and / or a device and / or a storage device and to forward it to the control device and / or the evaluation device and / or the projection device. The data communication interface can be realized, for example, in the form of a user interface of the thermal imaging camera and / or using another device, for example in the form of an external data device such as a smartphone, a tablet PC, a PC, or in the form of another, which appears appropriate to a person skilled in the art external data device, which is connectable via a data communication interface of the thermal imaging camera with the control device and / or the evaluation device and / or the projection device of the thermal imager. For example, a user interface such as an input device allows a user to input parameters superimposed on the projected image to be projected onto the scene. Alternatively or additionally, the data communication interface can be designed as a memory device. In particular, the invention thus makes it possible to provide a hand-held thermal imaging camera in which parameters to be projected, in particular working parameters, can be predefined in a simple manner. Furthermore, the data communication interface can be realized as an interface provided in particular for wireless communication, by means of which the thermal imager can exchange data, in particular send and / or receive working parameters. The data communication interface is signal technically at least to the control device and / or the evaluation device and / or the Projection device of the thermal imaging camera connected. Preferably, the data communication interface uses a standardized communication protocol for a transmission of electronic, in particular digital data. Advantageously, the data communication interface comprises a wireless interface, in particular, for example, a WLAN, Bluetooth, infrared, NFC, RFID interface or another wireless interface which appears expedient to a person skilled in the art. Alternatively or additionally, the data communication interface can also have a wired adapter, for example a USB or micro USB adapter. Thus, the data or parameters to be projected with the projectible image superimposed on the scenery, in particular working parameters, can also be reliably and reliably transmitted to the thermal imaging camera by an external data processing device, or read out from it for further processing. In one embodiment of the thermal imaging camera, the data communication interface can also serve for connection to a data network, for example the Internet.

In one embodiment of the hand-held thermal imaging camera, the data communication interface is provided to enable a transmission of information to be projected from at least one further device. Such a further device, in addition to the already mentioned data devices such as smart phone, tablet PC, PC or the like may also be another hand tool or measuring device. For example, the thermal imaging camera can read data from a detection device, which is designed to detect hidden objects under an examination surface. Alternatively or additionally, such measuring devices can also represent distance measuring devices, leveling devices or the like. The invention thus makes it possible to provide a hand-held thermal imaging camera which is capable of autonomously or user-independently determining data or parameters to be displayed, in particular working parameters.

Furthermore, a method according to the invention for non-contact determination of a two-dimensional temperature information of a scene, in particular for non-contact determination of a thermal image of a scene, is proposed. The method is based on a thermal imaging camera as described. In one embodiment of the method, this has at least the following method steps:

Measuring infrared radiation by means of an infrared detector array of the thermal imaging camera, which consists of a multiplicity of pixels which are sensitive to infrared radiation,

• Determining a two-dimensional temperature information, in particular a thermal image, of measured infrared radiation.

According to the invention, the two-dimensional temperature information, in particular the thermal image, is projected onto the scene using the projection device of the thermal imaging camera.

Drawings The invention is explained in more detail in the following description with reference to exemplary embodiments illustrated in the drawings. The drawing, the description and the claims contain numerous features in combination. The person skilled in the art will expediently also consider the features individually and combine them into meaningful further combinations. Like reference numerals in the figures indicate like elements.

Show it:

1 shows an embodiment of a thermal imaging camera according to the invention in a perspective front view,

FIG. 2 shows an embodiment of a thermal imaging camera according to the invention in a perspective rear view,

FIG. 3 shows a perspective, schematic rear view of an embodiment of the thermal imaging camera according to the invention in front of a scene to be measured,

FIG. 4 shows the essential components of an embodiment of the thermal imaging camera according to the invention,

FIG. 5a-c show schematic representations of an examined scene onto which a projectable image obtained from two-dimensional temperature information is projected, FIG.

FIG. 6 shows an embodiment of the method according to the invention. Description of the embodiments

In the following, a thermal imaging camera 10 according to the invention in the form of a hand-held thermal imaging camera 10 is presented. Each of FIGS. 1 and 2 shows an exemplary embodiment of this thermal imaging camera 10 in a perspective front view or in a perspective rear view. The thermal imaging camera 10 serves to determine a two-dimensional temperature information 12, in this exemplary embodiment a thermal image 12 a, of a scene 14 to be examined. Scenery 14 may be any arrangement to be examined, typically including objects, particularly surfaces of objects, or the like. Examples of such a scene 14 may be a house facade (see Figure 3), a fuse box, a group of people, a landscape or the like. A perspective, schematic rear view of a thermal imaging camera 10 according to the invention in front of a scenery 14 to be measured by way of example is shown in FIG.

The thermal imaging camera 10 comprises a housing 16 with a handle 18. With the handle 18, the thermal imaging camera 10 can be conveniently held in one hand during its use. The housing 16 of the thermal imager 10 furthermore has an output device in the form of a touch-sensitive screen 22 on a side 20 facing a user during use of the thermal imager 10, as well as operating elements 24 for user input and control of the thermal imager 10. In particular, the thermal imaging camera 10 also has a probe 24a, with which a user can determine a non-contact two-dimensional temperature information 12 of the scene to be examined

14 can trigger.

On the side facing away from the user 26 of the housing 16, an inlet opening 28 is provided in the housing 16. The inlet opening 28 defines (possibly in cooperation with an optics of the thermal imaging camera 10, not shown here) the detection area of the thermal imaging camera 10, which is shown in dashed lines in FIG. 3 by the solid angle area 30. The infrared radiation emitted in this solid angle region 30 or in this solid angle region 30 from the scene 14, in particular from the objects of the scene 14, is detected by the thermal imager 10. Immediately behind the inlet opening 28 is located in a scattering light-reducing light tube 32 a lens system as optics (not shown here). The lens system is permeable to radiation in the mid-infrared range and serves to focus infrared radiation on an infrared detector array (see FIG. 4) of the thermal imager 10.

On the side 26 of the housing 16 facing away from the user during use of the thermal imaging camera 10, a projection device 34 is provided in the housing 16, which is intended to convert a two-dimensional temperature information 12 determined by means of an infrared detector array 48 into a projectable image 36 and this to project projected image 36 onto the scene 14 (note: hereinafter, both projectable image and projected image are designated by reference numeral 36). In the exemplary embodiment presented, the projection device 34 consists of an evaluation device (not shown in detail) and a video projector 34a ("projector") which is arranged in the housing 16 of the thermal imager 10. The image 36 projected onto the scene 14 is used for augmenting the image the scene 14, in particular of a projection surface of the scene 14, defined working environment (see Figures 5a to 5c).

Furthermore, the thermal imaging camera 10 can have a camera operating in the visual spectrum (not shown here in detail) for recording visual images. Such images can be output together with a thermal image 12a generated from a temperature measurement initiated by the user, in particular at least partially superimposed or superimposed with the thermal image 12a.

On the underside of the thermal imaging camera 10, the handle 18 also has a receptacle 40 for receiving an energy store 42, which may be embodied by way of example in the form of a rechargeable accumulator or in the form of batteries.

As shown in FIG. 4, electrical components of the thermal imager 10 are mounted and interconnected in the interior of the thermal imager 10, for example on a printed circuit board. The electrical components comprise at least the projection device 34, a control device 44, an evaluation device 46 such as an infrared detector array 48 for detecting infrared radiation entering the inlet opening 28 of the thermal imager 10. The control device 44 represents, in particular, a device which comprises at least one control electronics as well as means for communication with the other components of the thermal imaging camera 10, in particular means for controlling and regulating the thermal imaging camera 10. The control device 44 is connected to the other components of the thermal imaging camera 10, In particular, the infrared detector array 48, the evaluation device 46, a data communication interface 50, the energy storage 42, a data memory 52, possibly a shutter mechanism 54 ("shutter"), but also with the controls 24,24a and the touch-sensitive screen 22 signal connected.

The infrared detector array 48 of the thermal imaging camera 10 is comprised of a plurality of infrared radiation sensitive pixels 56. The pixels 56 are designed to receive infrared radiation from the infrared radiation spectrum contained in the infrared radiation beam

Solid angle range 30, starting from the scene to be examined 14 in the inlet opening 28 of the thermal imaging camera 10 enters (see Figure 3) to detect. Each pixel 56 is provided to provide an electrical detection signal at its output that correlates to the radiated heat output of the infrared radiation to the pixel 56. These pixel-dependent detection signals are output, individually or in combination with other detection signals of other pixels 56, first to the control device 44 of the thermal imaging camera and forwarded by the latter to the evaluation device 46 of the thermal imager 10. In the illustrated embodiment, the pixels 56 are realized as infrared radiation-sensitive p / n diodes. Advantageously, the pixels 56 of the infrared detector array 48 are arranged like a matrix on the surface of the infrared detector array 48 facing the scenery. The number of pixels 56 in the illustrated embodiment is in particular 80 * 80 pixels, preferably 360 × 240 pixels, particularly preferably 640 × 480 pixels.

The evaluation device 46 is used to receive and evaluate detection signals of the infrared detector array 48, wherein the evaluation device 46 based on detection signals at least a plurality of pixels illuminated with infrared radiation 56 an evaluation of the two-dimensional temperature information 12, in particular the thermal image 12 a, the examined scenery 14 performs. The evaluation device 46 has at least one processor, a memory and an operating program with evaluation and calculation routines (in each case unspecified in FIG. 4). The evaluated two-dimensional temperature information 12, in particular the generated thermal image 5 12a, can be used by the evaluation device 46 for further processing and / or output to a user of the thermal imaging camera 10 by means of an output device, in particular by means of the projection device 34, and / or an external device by means of the data communication interface 50 are provided.

10

The projection device 34 of the thermal imaging camera 10 is provided for converting the two-dimensional temperature information 12 determined by means of the infrared detector array 48 into a projectable image 36. To generate the image data from the two-dimensional temperature information 12, the projectile onsvorrichtung 34 has an evaluation (not shown). In particular, the evaluation device of the projection device 34 is provided for determining from the two-dimensional temperature information 12 projectable contours 58, in particular isotherms 58 a (see FIG. 5 a). Furthermore, the evaluation device of the projection device 34 is provided for determining regions 20 having temperatures above a defined threshold (identified by reference numeral 60 in FIG. 5b) and / or regions having temperatures below a defined threshold, so that the associated regions are marked in the projected image 36 and / or can be highlighted (see Figure 5b). Furthermore, the evaluation unit of the projection device 34 is intended to

25 to superimpose data or information 62 received via the data communication interface 50 with the image 36 to be projected (see FIG. 5c). In particular, under the "overlay", the overlay, crossfade, combination or the like is at least the two-dimensional temperature information to be displayed with the projectable image as well as the additional information

30 62 provided by the data communication interface 50. In this way, a combined representation in the form of an "integrated image" or an integrated "augmentation" can be realized. The combined representation is intended to be projected onto the scene 14 by means of the projection device 34 and thus to be output to a user of the thermal imaging camera 10. The superimposed or superimposed projection of the image 36 represents an intuitively particularly understandable interpretation aid and / or presentation aid, which facilitates a user of the thermal imager 10 the interpretation and evaluation of the output two-dimensional temperature information 12.

In the embodiments of the hand-held thermal imaging camera 10 shown in FIG. 1 to FIG. 3, the projection device 34 has a video projector 34a. As shown in FIGS. 5a to 5c, the projection device projects in substantially the same direction and in the same solid angle 30 from which the thermal imager 10 measures infrared radiation.

FIGS. 5a to 5c schematically illustrate sceneries 14 that are examined by means of the thermal imaging camera 10, onto which a projectable image 36 obtained from a two-dimensional temperature information 12 is projected. The scenery consists of an example of a house facade, which is to be examined for thermal bridges. The thermal imaging camera 10, as also shown in FIG. 3, is positioned in front of the scene 14 in such a way that the entire building façade is covered by the solid angle region 30, so that from measured infrared radiation (process step 200 in FIG. 6) of the house façade a complete characterization of the house façade two-dimensional temperature information 12 can be determined (method step 202 in Figure 6). The two-dimensional temperature information 12, in particular the thermal image 12a, is first converted by the projection device 34 into a projectable image 36 (method step 206, see FIG. Subsequently, the projectable image 36 is projected onto the scene 14, in particular onto a projection surface located in the scenery 14 - in this case the house facade (method step 208 in FIG. 6). The projected image 36 serves to augment the scene 14 and the particularly clear and intuitively recordable output of the measurement results of the thermal imaging camera 10 to the user.

In FIG. 5 a, the projectable image 36 has been determined by evaluating projectible contours 58, in particular isotherms 58 a, from the two-dimensional temperature information 12. These contours 58, in particular isotherms 58 a, are projected onto the scene 14. In FIG. 5b, furthermore, by way of example, regions 60 having temperatures above a defined threshold - ie regions in which thermal bridges or cold bridges are present - are projected with the image 36 and marked or highlighted in this way. In particular, the marking or highlighting is done using different colors (represented here by different colors)

Hatching).

In FIG. 5c, superimposed on the projectable image 36, information 62 is projected onto the scene 14, which was received via the data communication interface 50 of the thermal imager 10. The illustration is about

Location data determined by a detection device in a separate measurement process. The detection device is designed, for example, to detect magnetic and non-magnetic metals, power lines, wooden substructures and / or plastic tubes located under the surface of the house façade (not shown here in detail.) The location data of the detection device are transmitted to the thermal imager 10 using the data communication interface 50 In the illustration, the location data relate to the course of an electrical line, wherein the course is projected as a dot-dashed line with the projectable image 36 superimposed on the scene 14.

In Figure 6, the inventive method is summarized. The illustrated method steps are based on the application example, which starts from the measurement scenario of FIG. 3, in which a user of the thermal imaging camera 10 is interested in an examination of the temperature distribution of the scene 14, in particular the house facade. Based on the measurement scenario shown in FIG. 3, the user of the thermal imaging camera 10 directs the thermal imaging camera 10 to measure the scene 14 to be examined in order to measure the scene 14 In a first method step 200, the thermal imaging camera 10 measures infrared radiation from the solid angle region 30 by means of the infrared detector array 48. The respective detection signals of the pixels 56 of the infrared detector array 48 are thereby transmitted to the evaluation device. tion 46, from which they are evaluated in method step 202 and are then available for further processing. In method step 202, in particular from measured infrared radiation, a two-dimensional temperature information 12, in particular a thermal image 12a, is determined. For this purpose, the evaluation device 46 of the thermal imaging camera 10 converts the detection signals of the pixels 56 of the infrared detector array 48 into temperature information and thus generates the two-dimensional temperature information 12. The two-dimensional temperature information 12 determined in this way is produced in method step 206 using the projection device 34 , in particular by the projection device 34, converted into a projectable image 36. For this purpose, for example, illumination limits, a color spectrum, an exposure correction or the like are analyzed and set. Optionally available information 62, which are provided by the data communication interface 50 in method step 204, are also taken into account in the step 206 in the conversion of the two-dimensional temperature information 12 into the projectable image 36 and integrated into or superimposed on the image 36 to be projected. Finally, in method step 208, the projection of the projectable image 36 onto the scene takes place with augmentation of the scene 14.

It should be noted that these method steps can proceed repeatedly, as indicated by the arrow 210. By a fast rate of the process steps 200 to 208, the image 36 projected onto the scene 14 appears to the user like a continuously updated image 36, in particular like a continuously updated thermal image 12a, in particular like a "live thermal image" of the scene 14.

Claims

claims

1. Hand-held thermal imaging camera (10) for non-contact determination of a two-dimensional temperature information (12) of a scene (14), in particular for non-contact determination of a thermal image (12a) of a scene (14), comprising a housing (16) with at least one infra red Detector array (48), which consists of a plurality of infrared radiation sensitive pixels (56), characterized in that in or on the housing (16) a projection device (34, 34a) is arranged, which for converting one by means of the infrared detector array (48) provided two-dimensional temperature information (12) in a projected image (36) and for projecting the projected image (36) on the scenery (14) is provided.

2. Handheld thermal imaging camera according to claim 1, characterized in that the projection device (34, 34a) has at least one light or video projector (34a) and / or a laser projector.

3. Handheld thermal imaging camera according to one of the preceding claims, characterized in that the projection device (34, 34a) projected substantially in the same solid angle (30) from which the thermal imager (10) measures infrared radiation.

4. Hand-held thermal imaging camera according to one of the preceding claims, characterized in that the projection device (34, 34a) is provided to determine from the two-dimensional temperature information (12) projectable contours (58), in particular isotherms (58a), and to project them ,

5. Handheld thermal imaging camera according to one of the preceding claims, characterized in that the projection device (34, 34a) is provided, using different light intensities, in particular different laser intensities, and / or different colors and / or different gray levels different areas (60) highlighting and / or highlighting the projected two-dimensional temperature information, in particular regions (60) of different temperature. Handheld thermal imaging camera according to one of the preceding claims, characterized in that the projection device (34, 34a) is provided to mark areas (60) with temperatures above a defined threshold and / or areas with temperatures below a defined threshold in the projection and / or highlight.

A handheld thermal imaging camera according to any one of the preceding claims, characterized by a data communication interface (50) arranged to provide at least one further piece of information (62) projectable with the projectable image (36) superimposed on the scene (14).

Handheld thermal imaging camera according to claim 7, characterized in that the data communication interface (50) is provided to allow a transmission of an information to be projected (62) at least from another device.

Method for non-contact determination of two-dimensional temperature information (12) of a scene (14), in particular for non-contact determination of a thermal image (12a) of a scene (14) by means of a thermal imaging camera (10) according to one of the preceding claims, comprising at least the following method steps:

Measuring infrared radiation by means of an infrared detector array (48) of the thermal imager (10), which consists of a plurality of infrared radiation sensitive pixels (56),

Determining a two-dimensional temperature information (12), in particular a thermal image (12a), from measured infrared radiation,

characterized in that the two-dimensional temperature information (12), in particular the thermal image (12a), is projected onto the scene (14) using a projection device (34, 34a) of the thermal imager (10).