PubMed Health⌕ Search

Biomedical subjects

Jindong Tian

Publications and source records attributed to Jindong Tian.

3 recordsLinked to original sources

Three-dimensional vision from a multisensing mechanism.

An approach for sensing a three-dimensional (3D) object surface with an arbitrary geometric shape is presented. Combining two different 3D sensing mechanisms, point-array encoding based on affine transformation and fringe encoding based on phase mapping, we construct a mathematic model for 3D vision in which the point-array encoding is initially applied to determine the fringe orders to create a control-vertex mesh with absolute coordinate values in 3D space. Then phase evaluation and phase unwrapping for fringe decoding is performed under the guidance of control-vertex mesh, leading to an absolute phase map and the corresponding range image of the test object. The computer simulations and experimental results are presented to demonstrate the theoretical prediction.

Journal Article↗

Three-dimensional digital imaging based on shifted point-array encoding.

An approach to three-dimensional (3D) imaging based on shifted point-array encoding is presented. A kind of point-array structure light is projected sequentially onto the reference plane and onto the object surface to be tested and thus forms a pair of point-array images. A mathematical model is established to formulize the imaging process with the pair of point arrays. This formulation allows for a description of the relationship between the range image of the object surface and the lateral displacement of each point in the point-array image. Based on this model, one can reconstruct each 3D range image point by computing the lateral displacement of the corresponding point on the two point-array images. The encoded point array can be shifted digitally along both the lateral and the longitudinal directions step by step to achieve high spatial resolution. Experimental results show good agreement with the theoretical predictions. This method is applicable for implementing 3D imaging of object surfaces with complex topology or large height discontinuities.

Journal Article↗

Three-dimensional vision with dual acousto-optic deflection encoding.

We report a new method of sensing a three-dimensional (3D) object surface with an arbitrary geometric shape. In this approach, the first-order beams diffracted from two acousto-optic deflectors (AODs) interfere with each other to form a spatial carrier that is used to encode the depth information from the 3D object surface. A direct digital synthesizer is utilized to control two AODs to generate sequentially spatial carriers with different spatial frequencies so that a modified temporal phase-unwrapping technique can be applied for decoding the shape information of the test surface. Preliminary experimental results are presented to demonstrate the effectiveness of this method.

Algorithms↗