JP7439623B2 - Vehicle interior imaging device - Google Patents

Description

The present invention relates to a vehicle interior imaging device having an imaging unit capable of capturing an image of a target area within the vehicle interior including a driver's face, and a lighting unit capable of illuminating the target area within the vehicle interior.

2. Description of the Related Art Vehicles such as automobiles are sometimes equipped with an imaging unit that can capture an image of a driver's face. Information about the driver's face that appears in the image captured by this imaging unit is used to determine whether the driver is falling asleep or looking inattentive. However, the interior of the vehicle tends to be dark, and a shadow often appears on the driver's face. When such a shadow occurs, information about the driver's face becomes unclear on the image captured by the imaging unit. Therefore, a vehicle is equipped with a lighting unit that can illuminate a target area within the vehicle interior.

An example of a vehicle interior imaging device having an imaging unit and a lighting unit includes a camera assembly having a camera and a plurality of infrared projectors arranged in line in the width direction of the vehicle. is arranged so that it coincides with the center of rotation of the steering wheel in the vehicle width direction, and the plurality of infrared projectors are distributed on both sides of the vehicle width direction relative to the camera, and the number of infrared projectors distributed on the left side is An example of an occupant image capturing device is one in which the number of infrared projectors distributed on the right side is the same as the number of infrared projectors distributed on the right side. (For example, see Patent Document 1.)

Japanese Patent Application Publication No. 2009-113621

However, in a vehicle interior imaging device in which an imaging unit such as a camera and a lighting unit such as an infrared floodlight are arranged on the steering column, as in the above example of the vehicle interior imaging device, the driver's hand holding the steering wheel is is located between the imaging unit and the lighting unit and the driver's face, and as a result, there is a possibility that the imaging by the imaging unit and the illumination by the lighting unit may be obstructed. That is, in the vehicle interior imaging device, there is a possibility that the driver's face cannot be clearly imaged.

As in the example of the above device, in a vehicle interior imaging device that has multiple lighting units such as multiple infrared floodlights, there is a risk that the cost of the multiple lighting units will increase, and the installation space for the multiple lighting units will increase. In addition, there is a risk that the installation work of the plurality of lighting units will become complicated. That is, in the vehicle interior imaging device, there is a possibility that the driver's face cannot be efficiently illuminated.

In view of these circumstances, it is desired that the vehicle interior imaging device efficiently illuminate the face of an occupant such as a driver and clearly image the occupant's face.

In order to solve the problem, a vehicle interior imaging device according to one aspect includes an imaging unit configured to be capable of capturing an image of a target area in the vehicle interior including the face of an occupant, and a vehicle interior imaging device configured to be capable of illuminating the target area. and an illumination unit configured to include a lens section, the imaging unit having a lens section arranged to be an origin of an imaging range that is imaged by the imaging unit and directed from the imaging unit to the outside of the imaging unit. , wherein the lighting unit has a light emitting part that is illuminated by the lighting unit and is arranged to be a starting point of an illumination range from the lighting unit to the outside of the lighting unit, The imaging unit and the lighting unit are arranged in a front region of the vehicle interior, and the lens section and the light emitting section are disposed in the front region of the vehicle interior so as to be shifted in the vehicle width direction with respect to the steering wheel, and the lens The lens portion and the light emitting portion are arranged in the vehicle vertical direction while at least partially overlapping in the vehicle width direction.

In the vehicle interior imaging device according to one embodiment, the face of a passenger such as a driver can be efficiently illuminated, and the face of the passenger can be clearly imaged.

FIG. 1 is a perspective view schematically showing a front area of a vehicle interior including a vehicle interior imaging device according to an embodiment, viewed from behind a driver. FIG. 2 is a front view schematically showing a vehicle interior imaging device together with a display unit according to an embodiment. FIG. 3 is a plan view schematically showing an imaging range and an illumination range in the vehicle interior imaging device according to an embodiment. FIG. 4 is a side view schematically showing an imaging range and an illumination range in the vehicle interior imaging device according to an embodiment.

A vehicle interior imaging device according to an embodiment will be described. Note that the vehicle interior imaging device according to this embodiment is installed in the interior of a vehicle, and the vehicle is an automobile. However, the vehicle may be a vehicle other than an automobile that has a cabin in which a passenger such as a driver can ride.

In the drawings used in the description of this specification, directions based on the vehicle are shown as follows. In FIGS. 1, 3, and 4, the front of the vehicle and the rear of the vehicle are indicated by a one-sided arrow F and a one-sided arrow B, respectively. In FIGS. 1 to 3, the left and right directions when facing the front of the vehicle are indicated by a single-sided arrow L and a single-sided arrow R, respectively. The vehicle width direction is indicated by a one-sided arrow L and a one-sided arrow R. Furthermore, in FIGS. 1, 2, and 4, the upper side of the vehicle and the lower side of the vehicle are indicated by a one-sided arrow U and a one-sided arrow D, respectively.

"Overview of vehicle interior imaging device"
An outline of the vehicle interior imaging device 10 according to the present embodiment will be described with reference to FIGS. 1 to 4. That is, the vehicle interior imaging device 10 is roughly configured as follows. As shown in FIGS. 1 to 4, a vehicle interior imaging device (hereinafter simply referred to as the "device" as necessary) 10 captures an object in the vehicle interior 1 including the face 2a (shown in FIG. 1) of a passenger 2. It has an imaging unit 20 configured to be able to image a region. The device 10 includes an illumination unit 30 configured to illuminate a target area within the vehicle interior 1.

The imaging unit 20 has a lens section 22 that is arranged to be the starting point of an imaging range 21 (shown in FIGS. 3 and 4) that is imaged by the imaging unit 20. The illumination unit 30 has a light emitting section 32 arranged to be the starting point of an illumination range 31 (shown in FIGS. 3 and 4) imaged by the illumination unit 30. Note that in FIGS. 3 and 4, each of the imaging range 21 and the illumination range 31 is indicated by hatching consisting of a plurality of diagonal lines, and the hatching of the illumination range 31 and the plurality of diagonal lines forming the hatching of the imaging range 21 are separated. The plurality of diagonal lines that form the line intersect with each other.

As shown in FIGS. 3 and 4, the imaging range 21 is defined from the imaging unit 20 to the outside of the imaging unit 20. The illumination range 31 is defined from the illumination unit 30 toward the outside of the illumination unit 30. The lens portion 22 and the light emitting portion 32 are arranged in the vehicle vertical direction while at least partially overlapping in the vehicle width direction.

Furthermore, the device 10 can be generally configured as follows. As shown in FIGS. 3 and 4, the imaging range 21 is defined around an imaging optical axis 21a that extends through the lens section 22 toward the target area. The illumination range 31 is defined around an illumination optical axis 31a that passes through the light emitting section 32 and extends toward the target area.

As shown in FIG. 1, the lens portion 22 and the light emitting portion 32 are disposed offset from the face 2a of the occupant 2 in the vehicle width direction. As shown in FIG. 3, the illumination optical axis 31a overlaps the imaging range 21 within a section located on the passenger 2 side (indicated by a one-sided arrow Q) from the imaging optical axis 21a when viewed in the vertical direction of the vehicle. . Furthermore, the illumination optical axis 31a can be made to substantially coincide with the imaging optical axis 21a when viewed in the vehicle vertical direction.

As shown in FIGS. 2 to 4, the imaging unit 20 has an imaging window 23 that opens to expose the lens portion 22 toward the vehicle interior 1. As shown in FIGS. The lighting unit 30 has a lighting window 33 that opens to expose the light emitting section 32 toward the vehicle interior 1. As shown in FIGS. 1 to 4, a display unit 3 having a display surface 3a configured to be able to display information to the occupant 2 is arranged in the vehicle interior 1. As shown in FIGS.

As shown in FIGS. 3 and 4, each of the imaging window 23 and the illumination window 33 is arranged on a virtual plane E (indicated by a two-dot chain line) that is substantially coplanar with the display surface 3a. Furthermore, as shown in FIGS. 1, 2, and 4, the lens section 22 is arranged above the light emitting section 32 in the vehicle.

"Details of the vehicle interior imaging device and vehicle interior"
Referring to FIGS. 1 and 2, the vehicle interior imaging device 10 and the vehicle interior 1 in which it is installed can be configured as follows in detail. As shown in FIG. 1, the face 2a of the occupant 2 included in the target area within the vehicle interior 1 is the face 2a of the driver 2. Such a vehicle interior imaging device 10 can also be called a driver monitoring system. The device 10 is arranged in a front region 1a of the vehicle interior 1 in the longitudinal direction of the vehicle.

The vehicle interior 1 has an instrument panel 4 located in its front region 1a. The vehicle interior 1 has a steering wheel 5 located so as to face the driver 2 in its front region 1a. The steering wheel 5 is located on one side in the vehicle width direction with respect to the substantially central area 4a of the instrument panel 4 in the vehicle width direction. The steering wheel 5 is rotatable around its central axis 5a. The steering wheel 5 is located at the rear of the vehicle with respect to the instrument panel 4.

As shown in FIGS. 1 and 2, the display unit 3 is a car navigation system. However, the display unit can also be a display unit other than a car navigation system having a display surface configured to be able to display information to a passenger, in particular a driver. For example, the display unit may be a meter panel having a speedometer, tachometer, etc., an audio unit, an air conditioning unit, etc.

The display unit 3 has a frame 3b located around a display surface 3a. The frame 3b is arranged on a virtual plane E (shown in FIGS. 3 and 4) that is substantially coplanar with the display surface 3a. However, the frame can also be arranged so as to protrude toward the vehicle interior with respect to the display surface to the extent that the display surface is visible to an occupant, particularly the driver.

The display section 3a of the display unit 3 is arranged in a substantially central area 1b of the front area 1a of the vehicle interior 1 in the vehicle width direction. Further, the display section 3a is arranged in a substantially central area 4a of the instrument panel 4. A substantially central region 1b of the front region 1a of the vehicle interior 1 substantially coincides with a substantially central region 4a of the instrument panel 4. The display section 3a is arranged closer to the vehicle interior 1 than the outer surface 4b of the instrument panel 4. The display section 3a is arranged above the vehicle with respect to the central axis 5a of the steering wheel 5.

The imaging unit 20 is configured to be able to acquire still images and moving images. The light emitting section 32 of the lighting unit 30 is configured using an LED (light emitting diode). However, the light emitting section can be configured using light emitting means other than LEDs. For example, the light emitting means may be an organic EL (organic electroluminescence), an incandescent lamp, a fluorescent lamp, or the like.

As shown in FIG. 1, the lens section 22 of the imaging unit 20 and the light emitting section 32 of the illumination unit 30 are arranged offset from the steering wheel 5 in the vehicle width direction. The lens portion 22 is arranged above the vehicle with respect to the central axis 5a of the steering wheel 5. Furthermore, the light emitting part 32 can also be arranged above the vehicle with respect to the center axis 5a of the steering wheel 5.

As shown in FIGS. 1 and 2, the imaging window 23 and the illumination window 33 are formed in the frame 3b of the display unit 3. However, the imaging window and the illumination window can also be formed in separate units adjacent to the display unit.

The lens portion 22 and the light emitting portion 32 are arranged between the upper and lower edges of the display surface 3a in the vehicle vertical direction. However, only one of the lens section and the light emitting section can be arranged between the upper and lower edges of the display surface. Furthermore, the lens section and the light emitting section can be arranged above the vehicle with respect to the upper edge of the display surface. The lens section and the light emitting section can also be arranged below the vehicle with respect to the lower edge of the display surface.

Further, the lens portion 22 and the light emitting portion 32 are arranged on the passenger 2, particularly the driver 2 side, with respect to the display surface 3a in the vehicle width direction. However, the lens section and the light emitting section can also be arranged on the opposite side of the display surface in the vehicle width direction from the occupant, particularly the driver. Further, the lens portion and the light emitting portion may be arranged between both side edges of the display surface in the vehicle width direction.

"Details of imaging range and illumination range"
Referring to FIGS. 3 and 4, the imaging range 21 and the illumination range 31 can be determined in detail as follows. As shown in FIGS. 3 and 4, the imaging range 21 is determined to be approximately rotationally symmetrical about the imaging optical axis 21a. The imaging range 21 is defined to have a substantially fan shape when viewed in a direction substantially perpendicular to the imaging optical axis 21a. Therefore, the imaging range 21 is determined to have a substantially fan shape when viewed in the vehicle vertical direction or the vehicle width direction.

The illumination range 31 is determined to be substantially rotationally symmetrical about the illumination optical axis 31a. The illumination range 31 is defined to have a substantially fan shape when viewed in a direction substantially orthogonal to the illumination optical axis 31a. Therefore, the illumination range 31 is defined to have a substantially fan shape when viewed in the vehicle vertical direction or the vehicle width direction.

As shown in FIG. 3, the imaging optical axis 21a is arranged substantially parallel to a virtual longitudinal straight line J extending in the longitudinal direction of the vehicle, when viewed in the vehicle vertical direction. As shown in FIG. 4, the distance H in the vertical direction between the center of the lens section 22 on the imaging optical axis 21a and the center of the light emitting section 32 on the illumination optical axis 31a is such that the imaging range 21 and the illumination range 31 are When viewed in this direction, the face 2a (shown in FIG. 1) of the occupant 2, particularly the driver 2, is determined to overlap at the position thereof. The imaging optical axis 21a is arranged substantially parallel to the virtual longitudinal straight line J when viewed in the vehicle width direction. The illumination optical axis 31a is arranged substantially parallel to the imaging optical axis 21a when viewed in the vehicle width direction. Furthermore, as shown in FIGS. 3 and 4, the viewing angle α of the imaging range 21 is smaller than the illumination angle β of the illumination range 31.

However, the imaging optical axis 21a can also be tilted toward the passenger 2 side, particularly the driver 2 side, or the opposite side with respect to the virtual longitudinal straight line J when viewed in the vertical direction of the vehicle. In particular, it is preferable that the imaging optical axis 21a be tilted toward the passenger 2 side, particularly toward the driver 2 side, with respect to the virtual longitudinal straight line J when viewed in the vehicle vertical direction. The imaging optical axis 21a can also be tilted upward or downward of the vehicle with respect to the virtual longitudinal straight line J when viewed in the vehicle width direction. In particular, it is preferable that the imaging optical axis 21a be tilted upward of the vehicle with respect to the virtual longitudinal straight line J. Furthermore, the illumination optical axis 31a can be tilted upward or downward with respect to the imaging optical axis 21a when viewed in the vehicle width direction. Further, the viewing angle α of the photographing range 21 can be made approximately equal to the illumination angle β of the illumination range 31. The viewing angle α of the photographing range 21 can also be made larger than the illumination angle β of the illumination range 31.

In the overlap section A in which the imaging range 21 and the illumination range 31 overlap, the illumination unit 30 can brightly illuminate the target area in the vehicle interior 1 that is imaged by the imaging unit 20 . Furthermore, the face 2a of the occupant 2, particularly the driver 2, can be clearly displayed on the image taken by the imaging device 20 of the target area in the vehicle interior 1 illuminated by the lighting unit 30. In particular, on this image, shadows caused by the hands 2b, arms 2c, nose 2d, etc. of the occupant 2, particularly the driver 2, are unlikely to appear on the face 2a.

As described above, the vehicle interior imaging device 10 according to the present embodiment includes the imaging unit 20 configured to be able to image a target area in the vehicle interior 1 including the face 2a of the occupant 2, and a unit configured to be able to illuminate the target area. an illumination unit 30 configured to The lighting unit 30 has a lens portion 22 arranged therein, and the lighting unit 30 is arranged so as to be illuminated by the lighting unit 30 and to be the starting point of an illumination range 31 extending from the lighting unit 30 to the outside of the lighting unit 30. The vehicle interior imaging device 10 includes a light emitting section 32, and the lens section 22 and the light emitting section 32 are arranged in the vehicle vertical direction while at least partially overlapping in the vehicle width direction.

In such a vehicle interior imaging device 10, an overlap section A in which the imaging range 21 and the illumination range 31 overlap is arranged from a starting point that at least partially overlaps each other when viewed in the vertical direction of the vehicle, to detect the face of the occupant 2. It can be determined to face a target area within the vehicle interior 1 including 2a. In such an overlap section A, the illumination unit 30 can brightly illuminate the target area so as to suppress the shadow of the target area reflected on the imaging unit 20. As a result, when the target area is imaged by the imaging unit 20 while being illuminated by the illumination unit 30, it is possible to suppress the occurrence of a shadow in the target area on the image captured by the imaging unit 20. Therefore, the face 2a of the occupant 2 such as the driver 2 can be efficiently illuminated, and the face 2a of the occupant 2 can be clearly imaged.

In the vehicle interior imaging device 10 according to the present embodiment, the imaging range 21 is defined around an imaging optical axis 21a extending toward the target area through the lens section 22, and the illumination range 31 is The illumination optical axis 31a extends toward the target area through the light emitting part 32, and the lens part 22 and the light emitting part 32 are disposed offset in the vehicle width direction with respect to the face 2a of the occupant 2. The illumination optical axis 31a overlaps the imaging range 21 within a section located on the passenger 2 side from the imaging optical axis 21a when viewed in the vertical direction of the vehicle.

In such a vehicle interior imaging device 10, the overlap section A can be defined so as to go toward the face 2a of the occupant 2 from starting points that at least partially overlap each other when viewed in the vertical direction of the vehicle. In such an overlap section A, the illumination unit 30 can reduce the shadow of the face 2a of the occupant 2 reflected in the imaging unit 20. As a result, when the face 2a of the occupant 2 is imaged by the imaging unit 20 while being illuminated by the lighting unit 30, it is possible to suppress the appearance of a shadow on the face 2a of the occupant 2 on the image captured by the imaging unit 20. In particular, even if the position of the face 2a of the occupant 2 shifts toward the front of the vehicle, it is possible to suppress an increase in shadows appearing on the face 2a of the occupant 2 on the image captured by the imaging unit 20.

In the vehicle interior imaging device 10 according to the present embodiment, the illumination optical axis 31a substantially coincides with the imaging optical axis 21a when viewed in the vehicle vertical direction. In such a vehicle interior imaging device 10, the overlap section A is defined as the entire target area in the vehicle interior 1 including the face 2a of the occupant 2 from a starting point that at least partially overlaps each other when viewed in the vertical direction of the vehicle. It can be determined that the In such an overlap section A, the illumination unit 30 can reduce the shadow of the entire target area reflected on the imaging unit 20. Especially at night, even when the entire target area is dark, the lighting unit 30 can brightly illuminate the entire target area reflected in the imaging unit 20. As a result, if the entire target area is imaged by the imaging unit 20 while being illuminated by the illumination unit 30, it is possible to suppress the occurrence of a shadow over the entire target area on the image captured by the imaging unit 20.

In the vehicle interior imaging device 10 according to the present embodiment, the imaging unit 20 has an imaging window 23 that opens to expose the lens portion 22 toward the vehicle interior 1, and the illumination unit 30 includes: It has an illumination window 33 that opens to expose the light emitting part 32 toward the vehicle interior 1, and each of the imaging window 23 and the illumination window 33 can display information toward the passenger 2. It is arranged on a virtual plane E that is substantially coplanar with the display surface 3a configured as follows.

Here, from the viewpoint of making it easier for the occupants 2, especially the driver 2, to visually recognize the display surface 3a of the display unit 3 of a car navigation system, etc., the interior layout of the vehicle interior 1 is typically such that the driver 2 and No obstacles are allowed to intervene between the surface 3a and the surface 3a. On the other hand, in the vehicle interior imaging device 10, each of the imaging window 23 and the illumination window 33 is arranged on a virtual plane E that is substantially coplanar with the display surface 3a. As a result, it is difficult for obstacles to intervene between the light emitting part 32 and the light emitting part 32. As a result, shadows caused by such obstacles may appear in the target area in the vehicle interior 1, particularly in the face 2a of the occupant 2. can be effectively suppressed.

In the vehicle interior imaging device 10 according to the present embodiment, the lens section 22 is arranged above the light emitting section 32 in the vehicle. In such a vehicle interior imaging device 10, for example, if the lens portion 22 is placed above the central axis 5a of the steering wheel 5, the lens portion 22 may be placed above the arm 2c of the driver 2 who operates the steering wheel 5. can be placed. Therefore, it is possible to efficiently prevent the fact that the face 2a of the driver 2 cannot be imaged due to the arm 2c of the driver 2 being reflected in the imaging unit 20, and the shadow of the arm 2c of the driver 2 appearing on the face 2a of the driver 2. It can be prevented. Therefore, the face 2a of the occupant 2 such as the driver 2 can be clearly imaged.

Although the embodiments of the present invention have been described so far, the present invention is not limited to the above-described embodiments, and the present invention can be modified and changed based on the technical idea thereof.

DESCRIPTION OF SYMBOLS 1... Vehicle interior, 2... Passenger, driver, 2a... Face, 3a... Display surface 10... Vehicle interior imaging device, apparatus 20... Imaging unit, 21... Imaging range, 21a... Imaging optical axis, 22... Lens part, 23... Imaging window 30...Illumination unit, 31...Illumination range, 31a...Illumination optical axis, 32...Light emitting section, 33...Illumination window E...Virtual plane

Claims (5)

an imaging unit configured to be able to image a target area within the vehicle interior including the face of an occupant;
and a lighting unit configured to illuminate the target area,
The imaging unit has a lens section that is arranged to be an origin of an imaging range that is imaged by the imaging unit and goes from the imaging unit to the outside of the imaging unit,
The lighting unit is a vehicle interior imaging device, wherein the lighting unit has a light emitting part that is illuminated by the lighting unit and is arranged to be a starting point of an illumination range from the lighting unit to the outside of the lighting unit,
The imaging unit and the lighting unit are arranged in a front area of the vehicle compartment,
The lens portion and the light emitting portion are disposed offset in the vehicle width direction with respect to the steering wheel in a front region of the vehicle interior, and the lens portion is disposed above the vehicle with respect to a central axis of the steering wheel.
A vehicle interior imaging device, wherein the lens section and the light emitting section are arranged in a vehicle vertical direction while at least partially overlapping in a vehicle width direction. The imaging range is determined around an imaging optical axis extending toward the target area through the lens portion,
The illumination range is defined around an illumination optical axis extending through the light emitting part toward the target area,
The lens portion and the light emitting portion are disposed offset in the vehicle width direction with respect to the face of the occupant,
The vehicle interior imaging device according to claim 1, wherein the illumination optical axis overlaps the imaging range within a section located on the passenger side from the imaging optical axis when viewed in the vertical direction of the vehicle. The vehicle interior imaging device according to claim 2, wherein the illumination optical axis coincides with the imaging optical axis when viewed in the vertical direction of the vehicle. The imaging unit has an imaging window that opens to expose the lens portion toward the vehicle interior,
The lighting unit has a lighting window that opens to expose the light emitting part toward the vehicle interior,
4. The vehicle according to claim 1, wherein each of the imaging window and the illumination window is arranged on a virtual plane coplanar with a display surface configured to display information to the passenger. The vehicle interior imaging device according to item (1). The vehicle interior imaging device according to any one of claims 1 to 4, wherein the lens section is arranged above the light emitting section in the vehicle.