Patent ID: 7645975

Claim:
A spatial information detector, comprising: at least two photoelectric converters configured to receive a light from a target space, into which a light intensity-modulated at a modulation signal having a predetermined frequency is being irradiated, and generate an electric output corresponding to an intensity of the received light; at least one electrode formed on each of said at least two photoelectric converters; a charge storage formed in each of said at least two photoelectric converters by applying a control voltage to said at least one electrode to collect at least part of electric charges generated in said each of said at least two photoelectric converters; a controller configured to control the control voltage applied to said at least one electrode such that an area of said charge storage in one of two different phase periods of said modulation signal is different from the area of said charge storage in an other phase period of said modulation signal; a charge ejector configured to output the electric charges collected in said charge storage; and an evaluator configured to evaluate the target space according to a difference between the electric charges collected in the one of said two different phase periods by said charge storage formed in one of said at least two photoelectric converters, and the electric charges collected in the other phase period by said charge storage formed in the other one of said at least two photoelectric converters, wherein said at least two photoelectric converters receive light from the target space, into which a flashing light is being irradiated, and said evaluator evaluates the target space in accordance with a difference between electric charges collected in a lighting period of said flashing light by said charge storage formed in one of said at least two photoelectric converters, and electric charges collected in a non-lighting period of said flashing light by said charge storage formed in the other one of said photoelectric converters.