Vehicle cabin lighting apparatus

• US 8,055,023 B2
• Filed: 07/05/2005
• Issued: 11/08/2011
• Est. Priority Date: 07/07/2004
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation, Nippon Soken, Inc. (DENSO Corporation)
• Original Assignee: DENSO Corporation, Nippon Soken, Inc. (DENSO Corporation)
• Inventors: Okada, Rokuro, Goto, Tomoyuki
• Primary Examiner(s): LEE, JOHN W
• Application Number:
  US11/173,148
• Publication Number:
  US 20060018641A1
• Time in Patent Office: 2,317 Days
• Field of Search: 382/100, 382/141, 382/104, 382/11, 382/232, 280/735, 280/739, 362/455, 362/520, 702155-156, 702/166, 706/15, 706/20
• US Class Current: 382/104
• CPC Class Codes: B60Q 3/80 Circuits; Control arrangements for dashboards B60Q3/16; for mass transit vehicles B60Q3/47
• CPC Class Codes: B60R 25/1004 Alarm systems characterised by the type of sensor, e.g. current sensing means using door lock sensors B60R25/1001
• CPC Class Codes: B60R 25/302 using recording means, e.g. black box
• CPC Class Codes: B60R 25/305 using a camera
• CPC Class Codes: G03B 15/02 Illuminating scene

Abstract

A plurality of lighting units are positioned forwardly of the driver seat in the cabin of a vehicle for applying infrared radiations in respective directions to the vehicle driver seated on the driver seat. The intensities of the emitted infrared radiations are controlled according to respective basic controlled variables depending on the illuminance in the vehicle cabin. The position and orientation of the face of the vehicle driver are recognized from an image captured of the vehicle driver by an imaging device, and the basic controlled variables are corrected according to the recognized position and orientation, thereby adjusting the intensities of the infrared radiations emitted from the lighting units and a balance of the infrared radiations emitted from the lighting units. Thereafter, the illuminance in the vehicle cabin and the recognized position and orientation change, then corrective coefficients for the basic controlled variables are updated depending on the changes.

Claims

1. A vehicle cabin lighting apparatus for lighting a vehicle cabin comprising:

a plurality of lighting units disposed at different positions, respectively, in the vehicle cabin, emitting intensities of light to allow an imaging device installed in the vehicle cabin to capture at all times an optimum image of a face of a vehicle driver;

the imaging device, disposed in the vehicle cabin, capturing an image of the vehicle driver, including the face of the vehicle driver, in the vehicle cabin;

a light emission controller, including a plurality of driver circuits and an image processor for processing data of the captured image by the imaging device, performing the following steps;

setting basic controlled variables for controlling the electric currents to be supplied to the plurality of lighting unit;

energizing the plurality of driver circuits to supply first electric currents to the plurality of lightning unit based on the set basic controlled variables;

acquiring a brightness of the image of the vehicle driver captured by the imaging device from the image processor;

determining whether the acquired brightness of the image of the vehicle driver falls in a preset allowable range;

correcting the set basic controlled variables if the acquired brightness of the image of the vehicle driver does not fall in the preset allowable range;

recognizing a position and orientation of the face of the vehicle driver;

calculating corrective coefficients including positional corrective coefficients, horizontal corrective coefficients and vertical corrective coefficients, based on the recognized position and orientation, which are based on a forward or rearward shift of the face of the vehicle driver, a horizontal shift of the face of the vehicle driver and a vertical shift of the face of the vehicle driver, respectively, from a standard orientation of the face of the vehicle;

calculating specific controlled variables based on the set basic controlled variables and the corrective coefficients;

energizing the plurality of driver circuits to supply second electric currents to the plurality of lighting units based on the calculated specific controlled variables, so that the intensities of light emitted from said plurality of lighting units commensurate with the calculated specific controlled variables, thereby ensuring the optimum image of the face of the vehicle driver is captured at all times.

2. The vehicle cabin lighting apparatus according to claim 1, further comprising:

a first illuminance sensor for detecting an illuminance in the vehicle cabin.

3. The vehicle cabin lighting apparatus according to claim 1, wherein said recognizing the position and orientation of the face of the vehicle driver includes determining the distances between feature points on the face of the vehicle driver and shapes of graphic patterns formed by lines interconnecting the feature points.

4. The vehicle cabin lighting apparatus according to claim 1, wherein said imaging device and said plurality of lighting units are disposed around a seat for imaging and lighting the vehicle driver and a vehicle occupant seated on the seat in the vehicle cabin.

5. The vehicle cabin lighting apparatus according to claim 1, further comprising:

a behavior detecting device that detects a behavior of the vehicle driver.

6. The vehicle cabin lighting apparatus according to claim 5, wherein said behavior detecting device detects a behavior of the vehicle driver from the image captured by the imaging device.

7. The vehicle cabin lighting apparatus according to claim 1, wherein the intensities of light emitted from said plurality of lighting units are infrared radiations.

8. A method for lighting a vehicle cabin comprising:

emitting intensities of light to allow an imaging device installed in the vehicle cabin to capture at all times an optimum image of a face of a vehicle driver by a plurality of lighting units disposed at different positions, respectively, in the vehicle cabin;

capturing an image of the vehicle driver, including the face of the vehicle driver, in the vehicle cabin by the imaging device deposed in the vehicle cabin;

controlling a light emission by a controller, including a plurality of driver circuits and an image processor for processing data of the captured image by the imaging device, comprising;

setting basic controlled variables for controlling the electric currents to be supplied to the plurality of lighting unit;

energizing the plurality of driver circuits to supply first electric currents to the plurality of lightning unit based on the set basic controlled variables;

acquiring a brightness of the image of the vehicle driver captured by the imaging device from the image processor;

determining whether the acquired brightness of the image of the vehicle driver falls in a preset allowable range;

correcting the set basic controlled variables if the acquired brightness of the image of the vehicle driver does not fall in the preset allowable range;

recognizing a position and orientation of the face of the vehicle driver;

calculating corrective coefficients including positional corrective coefficients, horizontal corrective coefficients and vertical corrective coefficients, based on the recognized position and orientation, which are based on a forward or rearward shift of the face of the vehicle driver, a horizontal shift of the face of the vehicle driver and a vertical shift of the face of the vehicle driver, respectively, from a standard orientation of the face of the vehicle;

calculating specific controlled variables based on the set basic controlled variables and the corrective coefficients;

energizing the plurality of driver circuits to supply second electric currents to the plurality of lighting units based on the calculated specific controlled variables, so that the intensities of light emitted from said plurality of lighting units commensurate with the calculated specific controlled variables, thereby ensuring the optimum image of the face of the vehicle driver is captured at all times.