Patent ID: 11860309
Assignee: TRW LIMITED
Field: Measurement (Instruments)
Classification: CPC G | IPC G

Claim 10:
11. A method of 3D imaging objects in a scene, comprising:
(a) illuminating a scene at a first instance with at least one first pulse of light comprising at least two discrete wavelengths, and illuminating the scene at a second instance with at least one second pulse of light having the same two wavelengths;
(b) directing the reflected or scattered light from objects in the scene for the first pulse onto a detector array via an optical modulator to form a first image of the scene, the modulator being arranged to apply a first modulation to the two wavelengths in the reflected portion of the optical pulse as a function of time;
(c) directing the reflected or scattered light from objects in the scene for the second pulse onto the detector array via an optical modulator to form a second image of the scene, the modulator being arranged to apply a second, different, modulation of the two wavelengths in the reflected portion of the optical pulse as a function of time; and
(d) comparing a first image obtained from the detector corresponding to the first pulse with a second image obtained from the detector corresponding to the second pulse to form a 3D image of the scene, in which the step (b) comprises modulating the two wavelengths such that the first wavelength is increasingly attenuated over time and the second wavelength is not attenuated or is decreasingly attenuated over that time, and in which step (c) comprises modulating the two wavelengths whereby the second wavelength is increasingly attenuated over time and the first wavelength is not attenuated or is decreasingly attenuated.