JP6493668B2 - Camera unit - Google Patents

Description

  The present invention relates to a camera unit.

  As disclosed in Patent Document 1, the vehicle security system is equipped with a failure diagnosis function for the monitoring camera. In the failure diagnosis function, a total of two images are taken at two timings during traveling. If they match, the camera is diagnosed as abnormal.

JP 2007-22360 A

  In the video of the surveillance camera, the image may be distorted due to an abnormality in the synchronization signal. Alternatively, the imaging range may move due to an optical axis shift. In these failure modes, there is a difference between images captured at two timings, and a camera failure cannot be detected. The camera is diagnosed as normal.

  According to some aspects of the present invention, it is possible to provide a camera unit that can reliably detect a failure of a surveillance camera.

An aspect of the present invention detects a failure based on an image of an imaging device, a wire having an facing surface facing the imaging device, an irradiation source that illuminates the facing surface, and an image of the wire that is illuminated with light from the irradiation source. The present invention relates to a camera unit including a detection unit.

The illuminance on the facing surface is lower than that of the subject. As a result, even when imaging is performed with the imaging device, the wire is not reflected in the image. Images are taken as usual. When the facing surface is illuminated with light from the irradiation source, the illuminance of the facing surface is increased. The wire is reflected in the image. Thus, the operation of the image sensor can be confirmed according to the change in the illuminance on the facing surface. If there is a change in the wire image illuminated by light from the illumination source, a failure of the surveillance camera can be detected.

  The wire may be assembled in a lattice shape. In this way, the wire can be arranged over the entire imaging region. Problems with the surveillance camera can be detected evenly throughout the screen.

  As described above, according to the disclosed aspect, it is possible to reliably detect a failure of the surveillance camera.

It is a perspective view which shows one Embodiment of a moving body. It is a perspective view which shows the structure of a camera unit roughly. It is a block diagram which shows roughly the circuit structure of a camera unit. It is a photograph which shows the presence or absence of the reflection of a wire with 1st illumination intensity and 2nd illumination intensity. It is a photograph which shows the presence or absence of the reflection of a wire with 1st illumination intensity and 2nd illumination intensity. It is a front view of the camera unit which shows other embodiment of a wire rod roughly. It is a perspective view which shows other embodiment of a moving body.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

(1) Configuration of Moving Body FIG. 1 shows an automobile 11 as an embodiment of the moving body. The automobile 11 includes a vehicle body 12. A drive recorder 13 is mounted on the vehicle body 12. The drive recorder 13 includes a camera unit 14. The camera unit 14 is disposed, for example, inside the windshield 15. The optical axis of the camera unit 14 is directed to the front of the vehicle body 12. The camera unit 14 outputs a video signal. The state in front of the vehicle body 12 is specified by the video signal. As described later, when the camera unit 14 detects a failure of the camera unit 14 by self-diagnosis, the camera unit 14 outputs a failure notification signal.

  The drive recorder 13 includes a storage device 16. The storage device 16 is connected to the camera unit 14. A video signal is supplied from the camera unit 14 to the storage device 16. The video signal is stored in the storage device 16. For example, a nonvolatile memory or a memory card may be used as the storage device 16.

  The drive recorder 13 includes an output terminal 17. The output terminal 17 is connected to the storage device 16. For example, a personal computer or other external device can be connected to the output terminal 17. Thus, the video signal can be supplied from the output terminal 17 to the external device. The external device can display video based on the video signal.

  The drive recorder 13 includes a warning lamp 18. For example, an LED is used as the warning lamp 18. The warning lamp 18 is connected to the camera unit 14. The warning lamp 18 is supplied with a failure notification signal from the camera unit 14. When the failure notification signal is supplied to the warning lamp 18, the warning lamp 18 is turned on. In this way, a failure of the camera unit 14 can be notified to the user.

(2) Configuration of Camera Unit As shown in FIG. 2, the camera unit 14 includes an image sensor 21. The image sensor 21 is mounted on the substrate 22, for example. For example, an image sensor such as a CMOS sensor or a CCD is used for the image sensor 21. The image sensor 21 detects the intensity of light (visible light or invisible light) for each pixel. An imaging signal is generated according to the detected intensity. An image is specified by the imaging signal. A control unit to be described later may be further mounted on the substrate 22.

  The camera unit 14 includes a lens holder 23. The lens holder 23 is formed from, for example, a resin material. The lens holder 23 surrounds the image sensor 21 on the substrate 22. The lens holder 23 holds the lens 24 in front of the image sensor 21. In front of the lens 24, a light shielding wall 25 is formed in the lens holder 23 so as to surround the periphery of the lens 24. The light shielding wall 25 defines an incident space 26 in front of the image sensor 21.

  The camera unit 14 includes a specimen, that is, a wire rod 27. The wire 27 is made of a wire having a diameter of about 1 mm, for example. The wire rod 27 is disposed inside the light shielding wall 25. The axis of the wire rod 27 may cross the incident space 26 along a plane orthogonal to the optical axis of the lens 24.

  The wire rod 27 has an facing surface 27 a that faces the image sensor 21. The facing surface 27a only needs to have a reflectance determined with respect to the light detected by the image sensor 21. In the installation environment, the first illuminance is established at the facing surface 27a. Since the facing surface 27a is surrounded by the light shielding wall 25 and is shadowed from the subject (for example, a landscape in front of the surveillance camera), the first illuminance of the facing surface 27a is lower than the illuminance of the subject.

  The camera unit 14 includes an irradiation source 28. For example, an LED is used as the irradiation source 28. The irradiation source 28 illuminates the facing surface 27a. When light is irradiated from the irradiation source 28, the second illuminance higher than the first illuminance is established at the facing surface 27a. The illuminance of the facing surface 27a is increased. The facing surface 27a can be easily switched between the first illuminance and the second illuminance depending on whether the irradiation source 28 is turned on or off.

  As shown in FIG. 3, the camera unit 14 includes a control unit 31. The control unit 31 includes a video processing unit 32 connected to the image sensor 21. An imaging signal is supplied from the imaging device 21 to the video processing unit 32. The video processing unit 32 generates a video signal based on the imaging signal. The video is specified by the video signal.

  The control unit 31 has a video output unit 33. The video output unit 33 is connected to the video processing unit 32. A video signal is supplied from the video processing unit 32 to the video output unit 33. The video output unit 33 outputs a video signal in accordance with the screen.

  The control unit 31 has a detection unit 34. The detection unit 34 is connected to the video processing unit 32 and the irradiation source 28. A video signal is supplied from the video processing unit 32 to the detection unit 34. The detection unit 34 controls on / off of the irradiation source 28. The detection unit 34 periodically supplies an ON signal to the irradiation source 28. The irradiation source 28 receives the ON signal and irradiates light. The detection unit 34 acquires a video signal of an image captured at the irradiation timing from the video processing unit 32. The detector 34 detects an image of the wire 27 in the image when the irradiation source 28 is turned on. In detection, the detection unit 34 compares the captured image with the reference image. In the reference image, an image of the wire 27 is drawn on the screen. The reference image is taken into the detection unit 34 from the storage unit 35, for example. The reference image may be generated based on, for example, an actual photograph. In generating the reference image, a control signal can be input from the outside of the control unit 31 to the detection unit 34. The detection unit 34 can store a reference image in the storage unit 35 in response to the supply of the control signal.

(3) Operation of Drive Recorder Next, the operation of the drive recorder 13 will be briefly described. When the engine of the automobile 11 is operated, power is supplied to the drive recorder 13. A video signal is output from the camera unit 14 in response to power supply. The video signal is stored in the storage device 16. In this way, the state in front of the vehicle body 12 is recorded. When the supply of power is stopped, the recording of the video signal ends. For example, the video signal of the latest 5 minutes is left in the storage device 16. When, for example, a personal computer or a smartphone is connected to the output terminal 17, the state in front of the vehicle body 12 can be displayed on the screen of the personal computer or the smartphone.

  In the camera unit 14, an imaging signal is output from the imaging device 21. When the irradiation source 28 is turned off, the first illuminance is established at the facing surface 27a. As shown in FIG. 4 (a), even when imaging is performed with the imaging device 21, the illuminance of the facing surface 27a of the wire rod 27 is lower than that of the subject and close to the imaging device 21 and is not in focus so that the image is not focused. The wire rod 27 is not reflected. Images are taken as usual.

  The detection unit 34 performs failure diagnosis periodically (for example, at intervals of 10 seconds, 1 minute, or 5 minutes). In the failure diagnosis, the detection unit 34 supplies an ON signal to the irradiation source 28. When the irradiation source 28 is turned on, the illuminance of the facing surface 27a is switched from the first illuminance to the second illuminance. When the facing surface 27a is illuminated with the second illuminance, the illuminance of the facing surface 27a is increased. As shown in FIG. 4B, the wire rod 27 appears in the image. The detection unit 34 compares the captured image and the reference image by a method such as pattern matching. When the image sensor 21 operates normally, the images of the wire rod 27 overlap each other in the two images, and the pattern matching results match. When the image sensor 21 is out of order, the image of the wire 27 is deformed, moved, or disappears, and the pattern matching results do not match. Thus, the operation of the image sensor 21 can be confirmed according to the change in the illuminance of the facing surface 27a.

  In FIG. 4, a wire having a diameter of about 1 mm was placed about 1 cm in front of the lens 24 and focused on about 2 m in front of the lens 24 for imaging. On the other hand, in FIG. 5, similarly, a wire having a diameter of about 1 mm was placed about 1 cm in front of the lens 24, but was focused on about 5 cm in front of the lens 24. As shown in FIG. 5A, it was confirmed that the reflection of the wire 27 was avoided at the first illuminance. As shown in FIG. 5B, it was confirmed that the wire 27 appears in the image at the second illuminance.

  When the output of the image sensor 21 becomes abnormal, the image of the wire 27 is deformed, moved, or disappears from the image reproduced by the detection unit 34. The detection unit 34 compares the image of the wire rod 27 with the reference image and determines that the images do not overlap by the above-described pattern matching. At this time, the detection unit 34 recognizes a failure of the camera unit 14. The detection unit 34 outputs a failure notification signal. The failure notification signal is supplied to the warning lamp 18. The warning lamp 18 is lit. The failure of the camera unit 14 is notified to the user. Thus, periodic failure diagnosis is realized.

  For example, if the lens 24 is physically displaced, for example, the optical axis is shifted, the position of the wire rod 27 is shifted in the captured image. The image of the wire 27 does not overlap between the captured image and the reference image. Thus, the detection unit 34 recognizes a failure of the camera unit 14. The detection unit 34 outputs a failure notification signal. When a malfunction occurs in vertical synchronization or horizontal synchronization in the image sensor 21, the shape of the wire rod 27 is distorted in the captured image. Therefore, the image of the wire 27 does not overlap between the captured image and the reference image. Thus, the detection unit 34 recognizes a failure of the camera unit 14.

  The reference image is captured. For example, imaging may be performed at the time of initial movement when attached to the vehicle body 12 or at the time of factory shipment. In imaging, for example, a control signal is input to the detection unit 34 from the outside of the control unit 31. In response to the supply of the control signal, the detection unit 34 supplies an ON signal to the irradiation source 28 and acquires a video signal from the video processing unit 32. The wire rod 27 is reflected in the captured image. The detection unit 34 stores the acquired image in the storage unit 35.

  As shown in FIG. 6, the wire rods 27 may be assembled in a lattice shape. Thus, the wire rod 27 can be arranged in the entire imaging region. Problems of the image sensor 21 can be detected evenly over the entire screen.

(4) Other Embodiments FIG. 7 shows an automobile 11a according to another embodiment. An automatic driving device 41 is mounted on the automobile 11a. The automatic driving device 41 includes an image recognition sensor 42. The image recognition sensor 42 may be configured similarly to the camera unit 14 described above. The image recognition sensor 42 is fixed in front of the vehicle body 12. The image recognition sensor 42 is used for recognizing the lane 43, for example. The lane 43 is specified by the image captured by the image recognition sensor 42. The automatic driving device 41 controls the steering so as to follow the lane 43. The image recognition sensor 42 supplies a failure notification signal to the navigation system 44, for example. When the navigation system 44 receives the failure notification signal, the navigation system 44 displays a failure notification image on the screen of the display 45.

  DESCRIPTION OF SYMBOLS 11 Mobile body (automobile), 11a Mobile body (automobile), 21 Image pick-up element, 23 Lens holder, 25 Light-shielding wall, 26 Incidence space, 27 Wire material, 27a Opposing surface, 28 Irradiation source, 31 Control part, 42 Image recognition sensor.

Claims (2)

An image sensor;
A wire having an facing surface facing the image sensor;
An irradiation source for illuminating the facing surface;
A camera unit comprising: a detection unit that detects a failure based on an image of a wire illuminated by light from the irradiation source; The camera unit according to claim 1, wherein the wire is assembled in a lattice shape.