Patent Publication Number: US-2023164418-A1

Title: Sensor Device and Inspection Camera having such a Sensor Device

Description:
This application claims priority under 35 U.S.C. § 119 to patent application no. DE 10 2021 213 018.6, filed on Nov. 19, 2021 in Germany, the disclosure of which is incorporated herein by reference in its entirety. 
     BACKGROUND 
     US 8,218,074 B2 has already proposed a sensor device, in particular a sensor head, for an inspection camera, in particular for an endoscope, having at least one illumination unit for illuminating an examination object, having at least one camera unit for detecting the examination object, and having at least one housing unit in which the camera unit and the illumination unit are arranged. 
     SUMMARY 
     The disclosure proceeds from a sensor device, in particular a sensor head, for an inspection camera, in particular for an endoscope, having at least one illumination unit for illuminating an examination object, having at least one camera unit for detecting the examination object, and having at least one housing unit in which the camera unit and the illumination unit are arranged. 
     It is proposed that the housing unit is designed to taper along a longitudinal axis of the housing unit. The sensor device is in particular designed to detect, without destruction, examination objects that are difficult to access or inaccessible for a person. The examination object is, for example, an inner wall of a tube, a cavity, a rear wall of a fixedly installed device, an internal organ, in particular a digestive tract, of a living being, or the like. With respect to the longitudinal axis, the housing unit preferably comprises a front housing portion and a rear housing portion. The sensor device is in particular provided to be introduced, in particular inserted, into the examination object with the front housing portion first. The housing unit in particular comprises at least one cable pass-through arranged on the rear housing portion. The cable pass-through is provided in particular for receiving a cable unit of the inspection camera. The cable unit in particular connects the camera unit and/or the illumination unit to a power source of the inspection camera. The cable pass-through is preferably provided to align a central axis of the cable unit at the cable pass-through in parallel to the longitudinal axis of the housing unit. In particular, the cable pass-through is provided to concentrically align the cable unit and the housing unit with respect to the longitudinal axis. 
     On an outer side, the housing unit comprises at least one slanted surface which forms a tapering of the housing unit relative to the longitudinal axis. The slanted surface and/or a tangential plane of the slanted surface in particular enclose/encloses an acute angle with the longitudinal axis. The slanted surface may be arranged in the front housing portion, in the rear housing portion, and/or between the front and rear housing portions. The slanted surface may be flat or curved, in particular rotationally symmetrical with respect to the longitudinal axis. For example, a part of the housing unit, in particular the front housing portion and/or the rear housing portion, or the entire housing unit is conical, frustoconical, pyramidal, frustopyramidal, wedge-shaped, rotationally hyperboloidal, rotationally paraboloidal, spherical, hemispherical, or the like. The housing unit may taper continuously or in multiple stages. If both the front housing portion and the rear housing portion form a taper, these tapers may taper in the same direction or in opposite directions along the longitudinal axis of the housing unit. The housing unit preferably has a maximum longitudinal extension parallel to the longitudinal axis, in particular along the longitudinal axis. Preferably, the housing unit has a maximum transverse extension perpendicular to the longitudinal axis and a minimum transverse extension different from the maximum transverse extension. In particular, the slanted surface connects the maximum transverse extension to the minimum transverse extension. The maximum transverse extension may be arranged in the front housing portion, in the rear housing portion, and/or between the front and rear housing portions. The minimum transverse extension is preferably arranged in the front housing portion or in the rear housing portion, in particular at one end of the housing unit along the longitudinal axis. The maximum longitudinal extension may be greater or less than the maximum transverse extension and/or the minimum transverse extension. 
     The slanted surface extends in parallel to the longitudinal axis, preferably over a substantial part of the maximum longitudinal extension of the housing unit. The term “substantial part” of a reference length is to be understood in particular to mean at least 15%, preferably more than 25%, particularly preferably more than 33%, optionally more than 50%, of an overall length of the reference length. A minimum transverse extension is preferably less than the maximum transverse extension by at least 1%, preferably more than 3%, particularly preferably more than 5%, of the maximum transverse extension. In at least one embodiment, the minimum transverse extension is in particular quasi-punctiform and forms, for example, an apex of a curvature or of a tip. In an alternative embodiment, the minimum transverse extension is a maximum extension of a front surface of the housing unit, in particular of the front housing portion, which is in particular perpendicular to the longitudinal axis. 
     The camera unit and the illumination unit are in particular arranged inside the housing unit. The housing unit in particular comprises a contiguous outer housing, which forms the taper and in which the camera unit and the illumination unit are arranged together. Optionally, the housing unit comprises at least one structural element, which divides an interior space of the outer housing into a plurality of subspaces. The outer housing may be formed from one piece or may be composed of a plurality of mounting part housings, in particular mounting half shells. In particular, the housing unit comprises at least one illumination opening through which the illumination unit can illuminate the examination object. Alternatively or additionally, the housing unit is at least partially formed from a light-transmissive material, in particular from a transparent or translucent material. The housing unit preferably comprises at least one camera opening for passing light through the housing unit toward the camera unit. The camera unit in particular comprises at least one camera element, optionally a plurality of camera elements. Preferably, the at least one camera element is designed as a photodetector, in particular as an active pixel sensor (CMOS sensor) or a charged-coupled device sensor (CCD sensor). The illumination unit preferably comprises at least one illumination element, and particularly preferably at least one further illumination element. Preferably, the illumination unit comprises at least one inorganic or organic light-emitting diode (LED, OLED) as the illumination element and/or as the further illumination element. In an advantageously compact embodiment, the illumination unit and the camera unit comprise a common printed circuit board on which the at least one camera element and the at least one illumination element are arranged. Alternatively, the illumination unit and the camera unit are formed separately from one another and in particular are arranged at a distance from one another within the housing unit, in particular on different printed circuit boards. 
     As a result of the embodiment according to the disclosure of the sensor device, the sensor device can advantageously be easily moved within the examination object. In particular, a sliding movement of the sensor device within the examination object may be advantageously supported. In particular, a risk of the sensor device getting caught and/or stuck within the examination object can advantageously be kept small. In particular, a risk of damaging the sensor device and/or the examination object may be advantageously kept small. 
     It is furthermore proposed that with respect to the longitudinal axis, the housing unit comprises a front housing portion, in particular the one already mentioned, a rear housing portion, in particular the one already mentioned, and a cable pass-through, in particular the one already mentioned, arranged on the rear housing portion, for connecting the camera unit and/or the illumination unit to a power source, in particular the one already mentioned, of the inspection camera, wherein the front housing portion is designed to taper along the longitudinal axis in a direction facing away from the rear housing portion. Along the longitudinal axis, the front housing portion in particular ends with the minimum transverse extension. In planes perpendicular to the longitudinal axis, along the longitudinal axis, the rear housing portion may have a constant transverse extension, in particular the maximum transverse extension of the housing unit, or may have a variable transverse extension. As a result of the embodiment according to the disclosure, a risk of getting caught when introducing the sensor device into the examination object can advantageously be kept small. 
     Furthermore, it is proposed that the housing unit is asymmetrical with respect to a center plane that is parallel to the longitudinal axis and goes through a geometric center of gravity of the housing unit. In particular, the housing unit comprises at least one housing wall extending in parallel to the longitudinal axis. In particular, the slanted surface and the housing wall parallel to the longitudinal axis are opposite one another with respect to the center plane. Alternatively, the housing unit comprises at least one further slanted surface as an outer wall, which is opposite the slanted surface with respect to the center plane. For example, the further slanted surface or a tangential plane of the further slanted surface encloses with the longitudinal axis a further acute angle, which is different from the acute angle between the slanted surface or the tangential plane of the slanted surface and the longitudinal axis. Alternatively, the slanted surface is curved and the further slanted surface is flat, or the slanted surface is flat and the further slanted surface is curved. As a result of the embodiment according to the disclosure, a deflection of the sensor device around a corner or bend within the examination object can be advantageously supported at least in one direction. In addition, an advantageously large interior space within the housing unit can be maintained at the same time. 
     Furthermore, it is proposed that an edge of the housing unit delimiting a cable pass-through, in particular the one already mentioned, of the housing unit has a maximum transverse extension, perpendicular to the longitudinal axis, in particular the maximum transverse extension already mentioned, of the housing unit in a plane perpendicular to the longitudinal axis. In particular, the maximum transverse extension of the housing unit is insignificantly greater than a maximum opening width of the cable pass-through. The term “insignificantly greater” is to be understood in particular to mean greater by less than three times a maximum material thickness of the housing unit, preferably by less than two times a maximum material thickness of the housing unit, in particular by at most one time a maximum material thickness of the housing unit. Preferably, the maximum transverse extension of the housing unit is at least substantially equal to a maximum cable transverse extension of the cable unit. The term “substantially equal” is to be understood in particular to mean equal with a deviation of less than 10%, preferably less than 5%, in particular less than 3%. In particular, the cable pass-through is provided to arrange the cable unit and the housing unit at least substantially flush with one another, in particular to arrange them next to one another perpendicularly to the longitudinal axis with an offset of less than 1 mm, preferably less than 0.5 mm. As a result of the embodiment according to the disclosure, a shoulder between the cable unit and the sensor device can advantageously be avoided. In particular, a risk of getting caught when the sensor device is removed from the examination object may advantageously be kept small. 
     It is furthermore proposed that with respect to the longitudinal axis, the housing unit comprises a front housing portion, in particular the one already mentioned, a rear housing portion, in particular the one already mentioned, and a cable pass-through, in particular the one already mentioned, arranged on the rear housing portion, for connecting the camera unit and/or the illumination unit to a power source, in particular the one already mentioned, of the inspection camera, wherein the rear housing portion is designed to taper along the longitudinal axis in a direction facing away from the front housing portion. In particular, the rear housing portion has a minimum rear transverse extension in a plane which is perpendicular to the longitudinal axis and in which the cable pass-through is arranged. The minimum rear transverse extension may be identical to, equal to, or different from the minimum transverse extension of the entire housing unit. The minimum rear transverse extension is in particular greater than the maximum opening width of the cable pass-through. The minimum rear transverse extension is preferably less than the maximum transverse extension of the housing unit. In particular, the housing unit widens, in particular continuously, starting from the cable pass-through along the longitudinal axis up to the maximum transverse extension. In planes perpendicular to the longitudinal axis, along the longitudinal axis, the front housing portion may have a constant transverse extension, in particular the maximum transverse extension of the housing unit, or may have a variable transverse extension. As a result of the embodiment according to the disclosure, a shoulder between the cable unit and the sensor device can advantageously be avoided. In particular, a risk of getting caught when the sensor device is removed from the examination object may advantageously be kept small. 
     Furthermore, it is proposed that the sensor device comprises at least one protective window, closing the housing unit, for protecting the camera unit and at least one further protective window for protecting the illumination unit, wherein the protective window and the further protective window are formed separately from one another. The protective window is in particular arranged in the camera opening of the housing unit. The protective window is preferably made of a transparent material. The further protective window is in particular arranged in the illumination opening. The further protective window may be made of a transparent or translucent material. The camera opening and the illumination opening of the housing unit may be integrally formed, in particular forming a single opening or may be arranged at a distance from one another. The protective window preferably comprises a camera surface facing the camera unit, an object surface provided to face the examination object, and at least one side wall connecting the camera surface and the object surface to one another. The further protective window preferably comprises an illumination surface facing the illumination unit, a further object surface provided to face the examination object, and at least one further side wall connecting the illumination surface and the further object surface to one another. The protective windows may optionally be designed as optical lenses. Preferably, the sensor device comprises at least one blocking element arranged on the side wall of the protective window and/or on the side wall of the further protective window, in particular between the protective windows. The blocking element is in particular made of a non-light-transmissive material. The blocking element is in particular provided to block internal housing light from the illumination unit, in particular by absorption and/or reflection. In particular, the blocking element is provided to block internal housing light from being coupled from the illumination unit into the camera unit. The term “internal housing light” is in particular to be understood to mean light that is generated within the housing unit and, without leaving the housing unit, can be detected by the camera unit, in particular as scattered light, in particular in contrast to light that is emitted or reflected by the examination object. The blocking element is preferably designed as a structural element, in particular a spacer, of the housing unit. Alternatively, the blocking element is designed as a film or coating applied to the side wall and/or the further side wall. As a result of the embodiment according to the disclosure, an amount of light of the illumination unit that has not interacted with the examination object and impinges on the camera unit can advantageously be kept small. In particular, conduction of the light from the further protective window to the protective window can advantageously be kept small. 
     In addition, it is proposed that the protective window and the further protective window are arranged at an offset from one another in a direction parallel to the longitudinal axis. The protective window in particular has a maximum window thickness between the camera surface and the object surface. The further protective window in particular has a further maximum window thickness between the illumination surface and the further object surface. Preferably, the protective window and the further protective window are arranged in parallel to the longitudinal axis at an offset of more than the maximum window thickness, in particular more than two times the maximum window thickness, and/or more than the further maximum window thickness, in particular more than two times the further maximum window thickness. The protective window that is arranged closer to, in particular on, the longitudinal axis, is preferably offset in the direction of the front housing portion, while the protective window that is arranged further away from the longitudinal axis is offset in the direction of the rear housing portion. The front housing portion can advantageously be strongly tapered as a result of the embodiment according to the disclosure. 
     It is furthermore proposed that a viewing direction of the camera unit is oriented at an acute angle, in particular an adjustable acute angle, to the longitudinal axis in order to detect the examination object through a slanted surface, in particular the one already mentioned, of the housing unit tapering the housing unit. The viewing direction is in particular a central axis of a maximum viewing angle of the camera unit, in particular of the camera element. In one embodiment of the camera unit having a plurality of camera elements, each camera element preferably has its own viewing direction, which may be oriented in parallel to one another, arranged in a common viewing plane, or arranged obliquely to one another. The viewing direction of the at least one camera element is preferably oriented, in particular can be oriented, at least substantially perpendicularly to the camera surface of the inspection window. In particular, the camera opening is partially or completely arranged in the slanted surface. Preferably, the viewing direction is oriented, in particular can be oriented, at least substantially perpendicularly to the slanted surface. In an advantageously simple embodiment, the acute angle, which the viewing direction encloses with the longitudinal axis, is fixed. Alternatively, the camera unit comprises at least one drive element for changing, in particular pivoting, an angle of the viewing direction relative to the longitudinal axis. The drive element may be provided to move, in particular to pivot, the camera element relative to the housing unit or to move, in particular to pivot, a reflective optical element. The reflective optical element is preferably a mirror, in particular a micromirror actuator. In an embodiment of the camera unit having the drive element for changing the viewing direction, an angular range adjustable with the drive element for the angle between the viewing direction and the longitudinal axis preferably also includes an orientation of the viewing direction parallel to the longitudinal axis and/or optionally an orientation of the viewing direction perpendicular to the longitudinal axis. Alternatively, the viewing direction of the camera unit is oriented, in particular fixedly, at least substantially in parallel or at least substantially perpendicularly to the longitudinal axis. As a result of the embodiment according to the disclosure, the examination object can advantageously be examined in detail. 
     It is furthermore proposed that the sensor device comprises a mounting plate, in particular the already mentioned printed circuit board, which is arranged in the housing unit and on which at least the camera unit is mounted, wherein the illumination unit comprises at least one illumination element, in particular the illumination element already mentioned, the already mentioned further illumination element or an additional illumination element, which is arranged on a side of the mounting plate facing away from the camera unit. In the following, this illumination element is referred to as the rearward illumination element. The camera unit, in particular the at least one camera element, is preferably arranged facing the front housing portion. The rearward illumination element is preferably arranged facing the rear housing portion. The rearward illumination element is in particular designed as an LED or OLED. Preferably, the rearward illumination element has a main emission direction which is at least substantially parallel to a surface of the mounting plate on which the rearward illumination element is mounted. The main emission direction of the rearward illumination element is preferably transverse, in particular perpendicular, to the longitudinal axis. In particular, the housing unit comprises a rearward illumination opening, in particular the illumination opening or an additional illumination opening, through which light from the rearward illumination element can be radiated out of the housing unit. The rearward illumination element is provided in particular to indirectly illuminate the examination object. As a result of the embodiment according to the disclosure, direct reflections on the examination object, which can lead to overexposure of the camera unit, can be advantageously avoided. 
     It is furthermore proposed that the housing unit forms at least one light guide which leads away from the illumination unit in parallel or transversely to the longitudinal axis. The housing unit comprises the light guide in particular instead of the further protective window. For example, the light guide is designed as an optical waveguide or as a planar optical waveguide structure (POWG). The light guide is in particular inserted in the illumination opening. As a result of the embodiment according to the disclosure, the further inspection window can advantageously be omitted. In particular, the illumination opening can advantageously be kept small. In particular, a risk of foreign objects and/or dirt penetrating into the illumination opening can advantageously be kept small. 
     Furthermore, it is proposed that the sensor device comprises at least one orientation sensor for determining a spatial orientation of the camera unit. The orientation sensor is preferably arranged within the housing unit. Alternatively, the orientation sensor is integrated into the cable unit of the inspection camera. The orientation sensor is preferably designed as an inertial measurement unit (IMU), which preferably comprises rotation rate sensors and/or acceleration sensors. The orientation sensor is preferably provided to detect an orientation of the housing unit, in particular of the camera unit, relative to gravity. The orientation sensor is in particular provided to associate orientation information, which indicates an orientation of the examination object relative to gravity, with an image, captured by the camera unit, of the examination object. Processing of the image captured by the camera unit and of the orientation information detected by the orientation sensor is preferably performed by an external computing unit, in particular a computing unit of the inspection camera, which is arranged outside the housing unit. Alternatively, the sensor device comprises a computing unit which is arranged in the housing unit and links the image and the orientation information to one another. For example, the orientation information may be stored and/ in particular output together with the image by means of a marking, for example in the form of an arrow, of a coordinate system or the like, within the image, or may in particular be used by the computing unit to rotate the image to a standard orientation, in particular to automatically adapt it to an orientation of a display for presenting the image. As a result of the embodiment according to the disclosure, an image of the examination object captured by the camera unit can advantageously be interpreted easily. In particular, points of interest of the examination object can advantageously be easily located. In particular, the sensor device can advantageously be intuitively navigated in the examination object. 
     In addition, an inspection camera, in particular an endoscope, having at least one sensor device according to the disclosure and having at least one power source, arranged at a distance from the housing unit, for supplying electrical power to the camera unit and/or the illumination unit is proposed. The inspection camera in particular comprises an operating unit, the already mentioned cable unit, and the sensor device. In particular, the sensor device is connected to the operating unit via the cable unit, in particular only via the cable unit. The operating unit in particular comprises an operating housing in which the power source is arranged. The operating housing can preferably be held by hand, in particular by one hand, and in particular without aids. The operating unit preferably comprises an output unit. The output unit preferably comprises a display for representing the image captured by the camera unit and/or the orientation information detected by the orientation sensor. The output unit is in particular inserted in the operating housing. Preferably, the operating unit comprises the already mentioned computing unit. The term “computing unit” is understood in particular to mean a unit having an information input, information processing, and an information output. Advantageously, the computing unit comprises at least one processor, a memory, input and output means, further electrical components, an operating program, regulating routines, control routines, and/or calculation routines. Preferably, the components of the computing unit are arranged on a common board and/or advantageously arranged in a common housing. The cable unit in particular comprises at least one power line connecting the camera unit and/or the illumination unit to the power source. The power source is preferably designed as an accumulator or battery. Alternatively, the power source is designed as a power connection, in particular for connecting to an external power grid. The operating unit preferably comprises at least one operating element, in particular at least for switching the sensor device on and/or off. Preferably, the cable unit comprises at least one data line connecting the camera unit and/or the orientation sensor to the computing unit. The cable unit in particular comprises a jacket in which the power line and the data line of the cable unit are arranged together. The jacket is preferably designed as a hose, in particular a strip-wound hose or a corrugated hose, made of metal or plastic. Preferably, the cable unit, in particular in an unwound state, has a greater, in particular more than five times greater, preferably more than ten times greater, particularly preferably more than twenty times greater, maximum longitudinal extension than the sensor device. As a result of the embodiment according to the disclosure, an inspection camera can be provided, which is advantageously easy to handle. 
     The sensor device according to the disclosure and/or the inspection camera according to the disclosure is/are not to be limited to the above-described application and embodiment. In order to fulfill a functionality described herein, the sensor device according to the disclosure and/or the inspection camera according to the disclosure can in particular comprise a number of individual elements, components, and units that deviates from a number mentioned herein. Moreover, in the case of the value ranges specified in this disclosure, values within the mentioned limits are also to be considered as disclosed and usable as desired. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further advantages become apparent from the following description of the drawings. Five exemplary embodiments of the disclosure are 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. 
       Shown are: 
         FIG.  1    a schematic diagram of an inspection camera according to the disclosure, 
         FIG.  2    a schematic diagram of a sensor device according to the disclosure, 
         FIG.  3    a schematic diagram of a further embodiment of a sensor device according to the disclosure, 
         FIG.  4    a schematic diagram of an embodiment of a sensor device according to the disclosure having a tapering on both sides, 
         FIG.  5    a schematic diagram of an alternative embodiment of a sensor device according to the disclosure, and 
         FIG.  6    a schematic diagram of an embodiment of a sensor device according to the disclosure having an asymmetrical taper. 
     
    
    
     DETAILED DESCRIPTION 
       FIG.  1    shows an inspection camera  12   a , in particular an endoscope. The inspection camera  12   a  comprises at least one sensor device  10   a  having a camera unit  20   a  (see  FIG.  2   ). The sensor device  10   a  comprises a housing unit  22   a . The camera unit  20   a  of the sensor device  10   a  is arranged in the housing unit  22   a . The inspection camera  12   a  in particular comprises an operating unit  49   a . Preferably, the inspection camera  12   a  comprises at least one cable unit  52   a . The sensor device  10   a  is in particular arranged at one end of the cable unit  52   a . The operating unit  49   a  is preferably arranged at an end of the cable unit  52   a , said end in particular facing away from the sensor device  10   a . The operating unit  49   a  comprises a power source  32   a . The power source  32   a  is in particular designed as an accumulator. The operating unit  49   a  in particular comprises a handle  54   a  in which the power source  32   a  is arranged. The power source  32   a  is arranged on the sensor device  10   a  at a distance from the housing unit  22   a . The power source  32   a  is provided to supply power to the sensor device  10   a , in particular to the camera unit  20   a . The operating unit  49   a  preferably comprises an output unit  56   a , in particular a display. The output unit  56   a  is preferably provided to output an image captured by the camera unit  20   a . The operating unit  49   a  comprises at least one operating element  58   a  for operating the sensor device  10   a  and/or the operating unit  49   a , e.g., for storing a single image captured by the camera unit  20   a , for switching the camera unit  20   a  on and/or off, or the like. 
       FIG.  2    shows the sensor device  10   a . The sensor device  10   a  comprises at least one illumination unit  14   a . The illumination unit  14   a  is provided to illuminate an examination object. The sensor device  10   a  comprises the camera unit  20   a . The camera unit  20   a  is provided to detect the examination object. The sensor device  10   a  comprises the housing unit  22   a . The camera unit  20   a  and the illumination unit  14   a  are arranged in the housing unit  22   a . The housing unit  22   a  is designed to taper along a longitudinal axis  24   a  of the housing unit  22   a . 
     With respect to the longitudinal axis  24   a , the housing unit  22   a  comprises a front housing portion  26   a  and a rear housing portion  28   a . The housing unit  22   a  comprises a cable pass-through  30   a  arranged on the rear housing portion  28   a . The cable pass-through  30   a  is provided to connect the camera unit  20   a  and/or the illumination unit  14   a  to the power source  32   a  of the inspection camera  12   a . In particular, the cable pass-through  30   a  is provided to receive the cable unit  52   a , in particular at least one data line and/or at least one power line of the cable unit  52   a . The front housing portion  26   a  is designed to taper along the longitudinal axis  24   a  in a direction facing away from the rear housing portion  28   a . In particular, the housing unit  22   a  is designed to taper over an entire length of the housing unit  22   a  in parallel to the longitudinal axis  24   a . By way of example, the housing unit  22   a  is rotationally paraboloidal. In particular, an apex of a parabola describing an outer wall of the housing unit  22   a  is arranged in the front housing portion  26   a . A maximum transverse extension  36   a  of the housing unit  22   a  perpendicular to the longitudinal axis  24   a  is in particular arranged in one plane with the cable pass-through  30   a . The sensor device  10   a  in particular comprises a mounting plate  44   a , in particular a printed circuit board, which is arranged in the housing unit  22   a  and on which at least the camera unit  20   a  is mounted. The illumination unit  14   a  preferably comprises at least one illumination element  46   a , in particular an LED. Preferably, the illumination unit  14   a  comprises a plurality of illumination elements  46   a , which are arranged in the shape of a circle, in particular at regular intervals, around a viewing direction of the camera unit  20   a . The at least one illumination element  46   a  is arranged on the mounting plate  44   a , in particular on the same side of the mounting plate  44   a  as the camera unit  20   a . A viewing direction of the camera unit  20   a  is in particular oriented in parallel to, in particular coaxially with, the longitudinal axis  24   a . The sensor device  10   a  comprises at least one protective window  38   a , closing the housing unit  22   a , for protecting the camera unit  20   a . The sensor device  10   a  comprises at least one further protective window  40   a ,  42   a , closing the housing unit  22   a , for protecting the illumination unit  14   a . The protective window  38   a  and the further protective window  40   a ,  42   a  are formed separately from one another. The protective window  38   a  and the further protective window  40   a ,  42   a  are arranged at an offset from one another in a direction parallel to the longitudinal axis  24   a . In particular, the housing unit  22   a  forms at least one blocking element  60   a ,  62   a , which is arranged on a side wall of the protective window  38   a  and/or of the further protective window  40   a ,  42   a . Preferably, the blocking element  60   a ,  62   a  extends in particular from an outer wall of the housing unit  22   a  to the mounting plate  44   a . 
     The sensor device  10   a  comprises an orientation sensor  50   a  for determining a spatial orientation of the camera unit  20   a . The orientation sensor  50   a  is in particular arranged within the housing unit  22   a . 
       FIGS.  3  to  6    show four further exemplary embodiments of the disclosure. The following descriptions and the drawings are substantially limited to the differences between the exemplary embodiments, wherein reference can basically also be made to the drawings and/or the description of the other exemplary embodiments, in particular of  FIGS.  1  to  2   , with respect to identically designated components, in particular with respect to components having the same reference signs. In order to distinguish the exemplary embodiments, the letter a is added to the reference signs of the exemplary embodiment in  FIGS.  1  to  2   . In the exemplary embodiments of  FIGS.  3  to  6   , the letter a is replaced by letters b to e. 
       FIG.  4    shows a sensor device  10   b  for an inspection camera  12   b . The sensor device  10   b  comprises at least one illumination unit  14   b . The illumination unit  14   b  is provided to illuminate an examination object. The sensor device  10   b  comprises a camera unit  20   b . The camera unit  20   b  is provided to detect the examination object. The sensor device  10   b  comprises a housing unit  22   b . The camera unit  20   b  and the illumination unit  14   b  are arranged in the housing unit  22   b . The housing unit  22   b  is designed to taper along a longitudinal axis  24   b  of the housing unit  22   b . The sensor device  10   b  comprises a mounting plate  44   b , in particular a printed circuit board, arranged in the housing unit  22   b . At least the camera unit  20   b  is mounted on the mounting plate  44   b . The illumination unit  14   b  comprises at least one illumination element  46   b  arranged on a side of the mounting plate  44   b  facing away from the camera unit  20   b . 
     The sensor device  10   b  comprises an orientation sensor  50   b  for determining a spatial orientation of the camera unit  20   b . The orientation sensor  50   b  is in particular integrated into a cable unit  52   b  of the inspection camera  12   b . Preferably, the orientation sensor  50   b  is arranged less far from the housing unit  22   b  at or in the cable unit  52   b  than a maximum longitudinal extension of the housing unit  22   b  parallel to the longitudinal axis  24   b . 
     With respect to further features of the sensor device  10   b , reference is made in particular to  FIGS.  1  to  2    and their description. 
       FIG.  4    shows a sensor device  10   c  for an inspection camera  12   c . The sensor device  10   c  comprises at least one illumination unit  14   c . The illumination unit  14   c  is provided to illuminate an examination object. The sensor device  10   c  comprises a camera unit  20   c . The camera unit  20   c  is provided to detect the examination object. The sensor device  10   c  comprises a housing unit  22   c . The camera unit  20   c  and the illumination unit  14   c  are arranged in the housing unit  22   c . The housing unit  22   c  is designed to taper along a longitudinal axis  24   c  of the housing unit  22   c . With respect to the longitudinal axis  24   c , the housing unit  22   c  comprises a front housing portion  26   c  and a rear housing portion  28   c . The housing unit  22   c  comprises a cable pass-through  30   c , arranged on the rear housing portion  28   c , for connecting the camera unit  20   c  and/or the illumination unit  14   c  to a power source of the inspection camera  12   c . The rear housing portion  28   c  is designed to taper along the longitudinal axis  24   c  in a direction facing away from the front housing portion  26   c . The front housing portion  26   c  is designed to taper along the longitudinal axis  24   c  in a direction facing away from the rear housing portion  28   c . In particular, the housing unit  22   c  has a diamond-shaped cross section in a plane parallel to the longitudinal axis  24   c . 
     A viewing direction of the camera unit  20   c  is oriented at an acute angle, in particular an adjustable acute angle, to the longitudinal axis  24   c  in order to detect the examination object through a slanted surface of the housing unit  22   c  tapering the housing unit  22   c . In particular, the camera unit  20   c  comprises at least one pivotably mounted camera element and a drive element for moving the camera element relative to the longitudinal axis  24   c . 
     With respect to further features of the sensor device  10   c , reference is made in particular to  FIGS.  1  to  3    and their description. 
       FIG.  5    shows a sensor device  10   d  for an inspection camera  12   d . The sensor device  10   d  comprises at least one illumination unit  14   d . The illumination unit  14   d  is provided to illuminate an examination object. The sensor device  10   d  comprises a camera unit  20   d . The camera unit  20   d  is provided to detect the examination object. The sensor device  10   d  comprises a housing unit  22   d . The camera unit  20   d  and the illumination unit  14   d  are arranged in the housing unit  22   d . The housing unit  22   d  is designed to taper along a longitudinal axis  24   d  of the housing unit  22   d . The housing unit  22   d  forms at least one light guide  48   d , which leads away from the illumination unit  14   d  in parallel or transversely to the longitudinal axis  24   d . 
     A viewing direction of the camera unit  20   d  is oriented at an acute angle, in particular an adjustable acute angle, to the longitudinal axis  24   d . In particular, the camera unit  20   d  comprises at least one micromirror actuator  64   d ,  66   d  for tilting the viewing direction relative to the longitudinal axis  24   d . 
     In a plane perpendicular to the longitudinal axis  24   d , an edge of the housing unit  22   d  delimiting a cable pass-through  30   d  of the housing unit  22   d  has a maximum transverse extension  36   d  of the housing unit  22   d  perpendicular to the longitudinal axis  24   d . In particular, the housing unit  22   d  and a cable unit  52   d  of the inspection camera  12   d  are flush with one another in a direction transverse to the longitudinal axis  24   d . 
     With respect to further features of the sensor device  10   d , reference is made in particular to  FIGS.  1  to  4    and their description. 
       FIG.  6    shows a sensor device  10   e  for an inspection camera  12   e . The sensor device  10   e  comprises at least one illumination unit  14   e . The illumination unit  14   e  is provided to illuminate an examination object. The sensor device  10   e  comprises a camera unit  20   e . The camera unit  20   e  is provided to detect the examination object. The sensor device  10   e  comprises a housing unit  22   e . The camera unit  20   e  and the illumination unit  14   e  are arranged in the housing unit  22   e . The housing unit  22   e  is designed to taper along a longitudinal axis  24   e  of the housing unit  22   e . The housing unit  22   e  is asymmetrical with respect to a center plane  34   e  that is parallel to the longitudinal axis  24   e  and goes through a geometric center of gravity of the housing unit  22   e . A viewing direction of the camera unit  20   e  is oriented at a defined acute angle to the longitudinal axis  24   e  in order to detect the examination object through a slanted surface of the housing unit  22   e  tapering the housing unit  22   e . 
     With respect to further features of the sensor device  10   e , reference is made in particular to  FIGS.  1  to  5    and their description.