Driver monitoring systems and methods with indirect light source and camera
A driver monitoring system of a vehicle includes: an infrared (IR) camera configured to, via a windshield, capture an image of a driver on a driver's seat within a passenger cabin of the vehicle; and an IR light source configured to transmit IR light directly toward the driver and the driver's seat.
1 . A driver monitoring system of a vehicle, comprising:
an infrared (IR) camera configured to, via a windshield, capture an image of a driver on a driver's seat within a passenger cabin of the vehicle,
wherein the IR camera is disposed below a top surface of a dashboard of the vehicle and configured to capture the image through an aperture in the top surface of the dashboard that narrows a field of view of the IR camera, and
wherein the IR camera has an angle of incidence of approximately 54-64 degrees with respect to the windshield;
an IR light source configured to transmit IR light directly toward the driver and the driver's seat; and
an IR reflective film disposed on the windshield and configured to reflect light from within the passenger cabin through the aperture toward the IR camera,
wherein the IR film has an R value of at least 80 percent for near IR light.
2 . The driver monitoring system of claim 1 wherein the IR light source is disposed at least partially below the top surface of the dashboard.
3 . The driver monitoring system of claim 1 wherein the IR film is disposed between inner and outer layers of glass of the windshield.
4 . The driver monitoring system of claim 1 wherein the IR film is disposed on an inner surface of an inner layer of glass of the windshield.
5 . The driver monitoring system of claim 1 wherein the IR film includes a coating for s-polarized light.
6 . The driver monitoring system of claim 1 wherein the IR film includes a coating for p-polarized light.
7 . The driver monitoring system of claim 1 wherein the IR camera includes a filter on a lens of the camera.
8 . The driver monitoring system of claim 7 wherein the filter includes a p-polarized filter.
9 . The driver monitoring system of claim 7 wherein the filter includes quarter waveplate circular polarization.
10 . The driver monitoring system of claim 1 further comprising at least one of:
a second IR light source configured to transmit IR light directly toward the driver and the driver's seat; and
a third IR light source configured to transmit light indirectly toward the driver via the windshield.
11 . The driver monitoring system of claim 1 further comprising:
a gaze module configured to determine a gaze of the driver based on the image from the IR camera; and
a monitor module configured to determine whether a location where the gaze of the driver intersects a vertical plane in front of the driver is within an area on the vertical plane.
12 . The driver monitoring system of claim 11 wherein:
the monitor module is configured to increment a timer value when the location where the gaze of the driver intersects the vertical plane in front of the driver is outside of the area on the vertical plane; and
the driver monitoring system further includes an alert module configured to output an alert to the driver when the timer value is greater than a predetermined value.
13 . The driver monitoring system of claim 12 wherein the alert module is configured to at least one of:
output a visual alert via one or more visual output devices;
output an audible alert via one or more speakers; and
output a haptic alert via one or more vibrating devices.
14 . A driver monitoring method for a vehicle, comprising:
by an infrared (IR) camera, via a windshield, capturing an image of a driver on a driver's seat within a passenger cabin of the vehicle,
wherein the IR camera is disposed below a top surface of a dashboard of the vehicle and configured to capture the image through an aperture in the top surface of the dashboard that narrows a field of view of the IR camera,
wherein the IR camera has an angle of incidence of approximately 54-64 degrees with respect to the windshield;
by an IR light source, transmitting IR light directly toward the driver and the driver's seat; and
by an IR reflective film disposed on the windshield, reflecting light from within the passenger cabin toward the IR camera and through the aperture,
wherein the IR film has an R value of at least 80 percent for near IR light.
15 . The driver monitoring method of claim 14 further comprising:
determining a gaze of the driver based on the image from the IR camera; and
determining whether a location where the gaze of the driver intersects a vertical plane in front of the driver is within an area on the vertical plane.