| 摘要 |
PROBLEM TO BE SOLVED: To precisely detect light (radiation light) radiated to an object of distance measurement, even when the brightness of background light such as sunlight with respect to the object of distance measurement changes. SOLUTION: A light extraction apparatus includes a radiation light extraction section 18 for calculating a brightness value with respect to radiation light of an irradiation wavelength corresponding to the brightness value of a nonirradiation wavelength set by a wavelength setting section 16, based on the ratio of brightness values between a first wavelength (the irradiation wavelength) and a second wavelength (the nonirradiation wavelength) calculated by an interwavelength information calculation section 15, and extracting radiation light a radiated to a preceding vehicle A as an object of distance measurement from an irradiation device 5, based on the difference between the calculated brightness value with respect to the irradiation wavelength and a brightness value of the irradiation wavelength on the occasion of radiating the radiation light. COPYRIGHT: (C)2008,JPO&INPIT |
