An image capturing apparatus for obtaining information regarding a depth of a subject includes: an illumination unit operable to cast a first illumination light beam that mainly contains a first wavelength and has a first intensity distribution on a plane perpendicular to an optical axis of the first illumination light beam and a second illumination light beam mainly containing a second wavelength and a third wavelength and having a second intensity distribution on a plane perpendicular to an optical axis of the second illumination light beam onto the subject, the second and third wavelengths being different from the first wavelength, the second intensity distribution being different from the first intensity distribution; and a depth calculation unit operable to calculate a depth-direction distance to the subject based on outgoing light beams from the subject.
This patent application is a divisional application of U.S. application Ser. No. 09/878,398 now U.S. Pat. No. 6,724,490, which was filed Jun. 12, 2001, which also claims priority based on a Japanese patent application No. 2000-176142 filed on Jun. 12, 2000, the contents of which are incorporated herein by reference.
Systems and methods are presented that use light sensors and computing devices to compute the depth of an object using shuttered light pulses. In one embodiment, depth is determined as follows: A light emitter emits a pulse of light that is directed toward an object. The pulse is reflected off the object and travels toward a beam splitter. The beam splitter splits the reflected pulse into multiple pulses, with each pulse directed to a shuttered sensor with a different shutter location. The shuttered sensors measure the integrated intensity of the light, and these values are used to determine the depth of the object. A method is presented which calibrates a system that has an arbitrary number of shutters and enables the system to determine the depth of an object, even in the presence of ambient illumination and scattered light.
A measurement sensor comprising a PSD (30) as an optoelectronic receiver, a transmitter (10, 12) for generating spots (22, 26), optics (14, 32) for reproducing the spots (22', 26') on the PSD (30) and means (44, 46, 48, 50, 52) for processing output signals (I1, I2) generated by said PSD (30) and for controlling the transmitter (10, 12) depending on the processed output signals (I1, I2) in order to measure the distance between the target (24) and the sensor by a triangulation technique is disclose closed. The transmitter comprises at least two optoelectronic signal sources (10, 12) for projecting at least two spots (22, 26) independent from each other on a target (24), the means (44, 46, 48, 50, 52) comprising a digitally controlled potentiometer (48) for balancing the output signals (I1, I2) and a digital processor (52) adapted for controlling the potentiometer (48).
An optical position-tracking system comprises a first light beam steering device for sweeping a first light beam through a first angular range to cause a reflection of the first light beam by a target. Additionally, the optical position-tracking system further comprises a second light beam steering device for sweeping a second light beam through a second angular range to cause a reflection of the second light beam by the target. Moreover, the optical position-tracking system enables determination of a position of the target using a triangulation technique utilizing a first angular value of the first light beam and a second angular value of the second light beam. The first angular value and the second angular value depend on the existence of the respective reflection.