Invention:
This invention is a method to improve accuracy and acquisition time of three-dimensional (3D) imaging systems by using illumination patterns with different spectrum and polarization states and simultaneously measuring the reflected patterns that can distinguish light of different spectrum and polarization states. Unlike existing techniques that utilize sequential measurements, this invention acquires all relevant information in a single shot and can be applied to rapidly changing scenes and objects. The invention describes different random patterns for projection and an adaptive or “smart” algorithm to change the patterns in real-time to improve accuracy of the measurement process. The projected patterns can be modified in real-time to improve sampling of local areas where there are large changes and high background noise.
Background:
Structured light illumination is used extensively in 3D imaging to measure topography of an object. Conventional methods utilize periodic fringe pattern of different phase to reconstruct the surface shape of an object. Different periodic fringes are projected onto the object sequentially and the reflected fringes are measured at different times. A minimum of three sets of fringes are needed for reconstruction and more fringes are often used to improve accuracy. When the different fringes are projected at the same time, the camera cannot identify and separate the different fringes. The measurement technique is limited by the time to project and to measure accurately the different fringe patterns and cannot be applied to rapidly changing or moving objects.
Applications:
- Real-time imaging
- Dental imaging
Advantages:
- Real-time
- Uses an adaptive/smart algorithm
- Can minimize high background noise
- Improved accuracy
