Patent ID: 8055023

Claim:
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.