JP2022115145A - Occupant monitoring apparatus - Google Patents

Abstract

To provide an occupant monitoring apparatus which can suppress the occurrence of such a situation that infrared light reflected on a reflection translucent member is visually recognized by an occupant.SOLUTION: An occupant monitoring apparatus according to the present invention comprises: an infrared light irradiation unit 12 which irradiates, with infrared light L2, a front windshield 3 provided in a vehicle 2 to transmit visible light and reflect the infrared light; a camera 13 which images a driver D of the vehicle 2 with the infrared light L2 reflected on the front windshield 3; and a housing 6 for housing the infrared light irradiation unit 12 and the camera 13. The infrared light irradiation unit 12 is provided in the housing 6 such that a reflection position R of the infrared light L2 on the front windshield 3 is superimposed on an irradiation region 19 of a headlight 18 of the vehicle 2 when viewed from a view point position of the driver D.SELECTED DRAWING: Figure 1

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an occupant monitoring apparatus that irradiates an occupant of a vehicle with infrared light to image the behavior of the occupant.

A head-up display device that generates and displays a virtual image by display light reflected by the reflective translucent member such as a front windshield of a vehicle or a combiner, superimposed on a real scene (landscape in front of the vehicle) transmitted through the reflective translucent member. contributes to safe and comfortable vehicle operation by providing a virtual image of information desired by the vehicle occupant (driver) while minimizing the movement of the driver's line of sight.

In addition, the head-up display device is equipped with a monitoring system that irradiates the passenger with infrared light reflected by the reflective translucent member and takes an image, and based on the captured image, the behavior of the passenger, such as looking away or falling asleep, can be grasped. (occupant monitoring device) is installed.

For example, the head-up display device described in Patent Document 1 forms a display image by reflecting visible light emitted from a display means with a combiner member toward a driver (user). Infrared irradiation means for irradiating infrared rays toward the driver, a mirror member for reflecting visible light emitted from the display means toward the combiner member and transmitting the infrared rays reflected by the driver and the combiner member, and a mirror member a plurality of imaging means for sensing infrared rays penetrating through a driver and imaging the driver from different directions; It is possible to accurately calculate the position of a person's eyes.

JP 2008-126984 A

Incidentally, when an occupant monitoring device captures an image of an occupant with infrared light, the light source of the infrared light is reflected on the reflective translucent member in a dark environment such as at night, and the occupant visually recognizes it as a red ball (point light source). Sometimes. There is a problem that this so-called glimpse makes the passengers feel uncomfortable, and especially the driver feels annoyed while driving.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an occupant monitoring apparatus capable of suppressing the occurrence of a situation in which infrared light reflected by a translucent reflecting member is visually recognized by an occupant. there is

In order to solve the above-mentioned problems, the present invention provides an infrared light irradiation means for irradiating infrared light to a reflective translucent member provided in a vehicle for transmitting visible light and reflecting infrared light; An image capturing means for capturing an image of an occupant of the vehicle by infrared light reflected by the translucent member; and a housing for housing the infrared light emitting means and the image capturing means, wherein the infrared light emitting means When viewed from the viewpoint of a passenger or another passenger of the vehicle, the light-reflecting member is provided on the housing such that the reflecting position of the infrared light on the translucent reflecting member overlaps with the irradiation area of the headlights of the vehicle. It is characterized by an occupant monitoring device characterized by:

Here, the occupant's viewpoint position is a position that is assumed to be the viewpoint (eye position) of any occupant of the vehicle, and is a position that is included in a certain spatial region that is determined by assuming the occupant's seat position and physique. can do.

The infrared light irradiating means is configured such that, when viewed from the viewpoint of the occupant or the other occupant, the infrared light reflection position on the translucent reflecting member overlaps with the low-beam irradiation area of the headlight, It may be provided in the housing.

Further, the infrared light irradiation means has a higher irradiation brightness than the reflection brightness of the infrared light reflected position on the reflecting translucent member when viewed from the viewpoint position of the passenger or the other passenger. It may be provided on the housing so as to overlap with the high-brightness region of the irradiation region.

Furthermore, the passenger may be a driver sitting in the driver's seat of the vehicle.

Advantageous Effects of Invention According to the present invention, it is possible to suppress the occurrence of a situation in which infrared light reflected by a translucent reflective member is visually recognized by an occupant.

1 is an explanatory diagram showing a vehicle provided with a head-up display device incorporating an occupant monitoring device according to a mode for carrying out the invention; FIG. FIG. 2 is an explanatory diagram showing the configuration of the head-up display device of FIG. 1; FIG. 2 is a perspective view showing the appearance of the head-up display device of FIG. 1; FIG. 2 is a plan view showing the appearance of the head-up display device of FIG. 1;

A mode for carrying out the present invention will be described based on the drawings.

As shown in FIGS. 1 and 2, a head-up display device (HUD) 1 incorporating an occupant monitoring device according to the present embodiment is installed inside an instrument panel 4 below a front windshield 3 of a vehicle 2. It is provided and projects display light L1, which is visible light, onto _a part of the front windshield 3 . _The display light L1 is reflected by the front windshield 3 to generate a virtual image V, which is superimposed on the real scene transmitted through the front windshield 3 to the driver D seated in the driver's seat (not shown) behind the steering wheel 5. Make V visible.

Further, the HUD ₁ has a function of monitoring the state of the driver D, and captures an image of the driver D by irradiating the driver D with infrared light L2.

Specifically, the HUD 1 is separated from the outside by being covered with a housing 6 molded of black ABS resin or the like to prevent the intrusion of external light, and a transparent cover glass 7 made of polycarbonate or the like is attached to the housing 6. A recessed opening 8 is formed. Inside the housing 6, a display unit 9, a plane mirror 10, a concave mirror 11, an infrared light irradiation unit 12, and a camera 13 are held and accommodated.

As shown in FIG. 2, the cover glass 7 has a quadrilateral plate shape that is curved downward, and is provided with a light blocking portion 14 for blocking visible light over the entire periphery (periphery of the four sides). ing. The light shielding portion 14 is formed by forming a black printed layer on a transparent base material such as polycarbonate.

The display unit 9 is provided with a display 15 composed of a light source, a liquid crystal panel, and the like, and projects and displays visible image light (display light L ₁ ) from the display 15 . The plane mirror 10 is formed by vapor-depositing a metal such as aluminum or a dielectric multilayer film on a glass molded to have a flat portion, and simply reflects visible light. The concave mirror 11 is formed by vapor-depositing metal such as aluminum on resin such as polycarbonate molded so as to have a concave portion, and magnifies and reflects visible light.

As shown in FIG. 3 , the infrared light irradiation unit 12 is provided in the vehicle width direction center side of the vehicle 2 so as to face the light shielding portion 14 below the cover glass 7 in the housing 6 . An infrared light transmitting portion 16 that transmits infrared light is provided in a portion of the light shielding portion 14 facing the infrared light irradiation unit 12 (the portion of the infrared light transmitting portion 16 of the light shielding portion 14 is a visible light). It consists of a black printed layer that shields light and transmits infrared light, and the other part consists of a black printed layer that shields visible light and infrared light.), the infrared light irradiation unit 12, Infrared light (near infrared light) L ₂ emitted by a light source (point light source) composed of light emitting diodes (LEDs) is irradiated toward the front windshield 3 through the infrared light transmitting portion 16 .

At that time, the viewpoint position of the driver D (here, it is an arbitrary position within the designed eye box 17, and three viewpoint positions with different heights within the eye box 17 are shown in FIG. 1). ₂ , the reflection position R of the infrared light L2 on the front windshield 3 (the position where the optical axis of the light source of the infrared light irradiation unit 12 intersects the front windshield 3) is the irradiation area of the headlights 18 of the vehicle 2. (All areas irradiated by the headlights 18) overlap with at least a part of 19 (for example, a high illuminance area surrounded by an 80% isolux curve with respect to the maximum illuminance in the irradiated area 19) (Fig. 1 , the distance from the headlights 18 of the vehicle 2 to the irradiation area 19 on the road surface is longer than the dimensions of the vehicle 2, so the space in front of the vehicle 2 and a part of the road surface are omitted from the illustration by broken lines. is doing.).

On the other hand, the camera 13 is provided at the center of the vehicle 2 in the vehicle width direction and in front of the infrared light irradiation unit 12 so as to face the infrared light transmitting portion 16 below the cover glass 7 in the housing 6. Near _- infrared image provided by an imaging element having sensitivity to infrared light L2 in the wavelength band irradiated from the infrared irradiation unit ₁₂ and a lens capable of transmitting the infrared light L2 and forming an image on the imaging element to shoot.

Further, in the case of the present embodiment, although detailed illustration is omitted here, the housing 6 has a pair of peripheral wall portions that are substantially orthogonal (intersect) with the vehicle width direction. As a configuration in which the infrared light irradiation unit 12 and the camera 13 are provided in the hollow space of the housing 6 slightly inside the one peripheral wall portion (one peripheral wall portion) located on the side near the imaginary center line that bisects the left and right there is The housing 6 here has four peripheral wall portions, and the two peripheral wall portions generally along the vehicle width direction shown in FIG. be done.

In the HUD ₁ , the display light L1 from the display unit 9 is reflected by the plane mirror 10, then magnified and reflected by the concave mirror 11, and passes through the transparent central portion 17 surrounded by the light shielding portion 14 of the cover glass 7. and projected onto the front windshield 3. The display light L1 projected onto the front windshield ₃ is magnified and reflected toward the driver D side to generate a virtual image V which is superimposed on the real scene transmitted through the front windshield 3 and displayed to the driver D.

On the other hand, the infrared light L2 from the infrared light irradiation unit ₁₂ passes through the infrared light transmitting portion 16 of the light shielding portion 14 of the cover glass 7 and is projected onto the front windshield 3. The light is reflected to the side of D and illuminates the driver D. Then, when reflected by the driver D, part of the infrared light _L2 follows a reverse path, and the infrared light _L2 that has passed through the infrared light transmission part 16 and entered the camera 13 causes the driver D to imaged. This imaging is performed periodically or irregularly while the virtual image V is being displayed, and the driver D is monitored based on the captured image.

An occupant monitoring device for a HUD 1 according to the present embodiment includes an infrared light irradiation unit that irradiates infrared light L2 onto a front windshield 3 provided in a vehicle ₂ that transmits visible light and reflects infrared light. 12, a camera 13 that captures an image of a driver D of the vehicle ₂ with the infrared light L2 reflected by the front windshield 3, and a housing 6 that houses the infrared light irradiation unit 12 and the camera 13. The light irradiation unit 12 is mounted on the housing 6 so that the reflection position R of the infrared light L2 on the front windshield 3 overlaps with the irradiation area 19 of the headlights 18 of the vehicle ₂ when viewed from the viewpoint position of the driver D. Since it is provided (accommodated), the light source of the infrared light irradiation unit 12 is reflected on the front windshield 3 in a dark environment outside the vehicle, and if the background is dark, it is visible to the driver D as a red ball. Even in this case, if the headlights 18 are turned on, the irradiation area 19 is superimposed on the red ball, and the background of the red ball becomes bright, so that the passenger can visually recognize the infrared light L2 reflected by the front windshield ₃ . It is possible to suppress the occurrence of the situation (Tamami).

The infrared light irradiation unit 12 is arranged so that the reflection position R of the infrared light L2 on the front windshield 3 overlaps with the low beam irradiation area of the headlights 18 of the vehicle ₂ when viewed from the viewpoint position of the driver D. It is desirable to be provided in the housing 6 at the same time, so that it is possible to suppress the occurrence of the headlights 18 whenever the headlights 18 are lit (not only in the case of high beam but also in the case of low beam).

In addition, the infrared light irradiation unit 12 is arranged so that the reflection position R of the infrared light L2 on the front windshield ₃ is higher _than the reflection brightness of the infrared light L2 at the reflection position R when viewed from the viewpoint position of the driver D. It is desirable that the housing 6 is provided so as to overlap with the high brightness region of the illumination region 19 having the highest illumination brightness.

In addition, the reflection luminance here means the infrared light L2 reflected by the front windshield ₃ when the infrared light L2 emitted from the light source is reflected by the front windshield ₃ and irradiated to the driver D. means the brightness of The illumination brightness of the illumination area 19 is the brightness (background brightness) of the light reflected by the road surface or the like that is the illumination target of the headlights 18. It means the brightness of the road surface or the like that is visible to the driver D after being reflected from the road surface or the like. Since the high-luminance region of the irradiation region 19 has a higher irradiation luminance _than the reflection luminance of the infrared light L2, the reflection position R overlaps with the high-luminance region, thereby ensuring the appearance of the shadow. can be suppressed.

Although the embodiments for carrying out the present invention have been exemplified above, the embodiments of the present invention are not limited to those described above, and may be modified as appropriate without departing from the gist of the invention.

For example, in the above embodiment, the front windshield of the vehicle is a translucent reflective member, but a combiner or the like may be used as the translucent reflective member instead of the front windshield.

In addition, the infrared light irradiation unit 12 is viewed from the viewpoint of other occupants other than the driver D sitting in the driver's seat of the vehicle 2, but the driver D sitting in the front passenger seat or the rear seat. 3 may be provided in the housing 6 so that the reflection position R of the infrared light L ₂ at 3 overlaps the irradiation area 19 of the headlight 18 of the vehicle 2 .

2 Vehicle 3 Front windshield (reflecting translucent member)
6 Enclosure (housing)
12 infrared light irradiation unit (infrared light irradiation means)
13 camera (imaging means)
18 headlight 19 irradiation area D driver (passenger)
L ₂ infrared light R reflection position

Claims (4)

infrared light irradiation means for irradiating infrared light to a reflective light-transmitting member provided in a vehicle that transmits visible light and reflects infrared light;
imaging means for imaging an occupant of the vehicle with the infrared light reflected by the translucent reflecting member;
A housing that accommodates the infrared light irradiation means and the imaging means,
The infrared light irradiating means is configured such that the position of the infrared light reflected on the translucent reflecting member overlaps with the irradiation area of the headlights of the vehicle when viewed from the viewpoint of the passenger or another passenger of the vehicle. (2) an occupant monitoring device provided in the housing; The infrared light irradiating means is configured such that, when viewed from the viewpoint of the occupant or the other occupant, the infrared light reflection position on the translucent reflecting member overlaps with the low-beam irradiation area of the headlight, 2. The occupant monitoring device according to claim 1, wherein the occupant monitoring device is provided in the housing. In the infrared light irradiation means, when viewed from the viewpoint of the passenger or the other passenger, the reflection position of the infrared light on the translucent reflecting member is higher than the reflection luminance of the infrared light at the reflection position. 3. The occupant monitoring device according to claim 1, wherein the occupant monitoring device is provided in the housing so as to overlap with a high luminance region of the irradiation region having high irradiation luminance. The occupant monitoring apparatus according to any one of claims 1 to 3, wherein the occupant is a driver sitting in a driver's seat of the vehicle.

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