Time-space coding method and apparatus for generating a structured light coded pattern
The present disclosure provides a time-space coding method and apparatus for generating a structured light coded pattern. Different coded patterns are outputted in time division by driving different light-emitting points based on a regular light-emitting lattice so as to time-space label a target object or a projection space. This method effectively overcomes the limitations of the fact that in the prior art, a plurality of projectors is needed to project different patterns in time division when it is required to project time-space labels of a plurality of patterns. According to the present method, by driving different light-emitting elements on the light-emitting substrate, different coded patterns are formed, and by using a time-division output technology, time-space labeling of an object may be finalized with only one projector. Moreover, this method may significantly improve the accuracy and robustness of three-dimensional depth measurement through time-space coding with a depth decoding algorithm.
1. A time-space coding method for generating a structured light coded pattern, comprising steps of:
S1: designing a regular light-emitting lattice of a certain size;
S2: coding light-emitting particle elements in the regular light-emitting lattice in step S1 in accordance with a coding rule to generate a coded pattern; and
S3: performing window uniqueness analysis to the coded pattern generated in step S2; in the case of meeting a window uniqueness distribution requirement, generating a final coded pattern; in the case of failure to meet the requirement, repetitively executing steps S2˜S3 till meeting the window uniqueness distribution requirement to thereby generate the final coded pattern.
2. The generating method according to claim 1 , further comprising:
S4: projecting the finally generated coded pattern in S3 directly or through duplication, arrangement, and splicing, onto a surface of a space object, to thereby finalize three-dimensional depth measurement of the object.
3. The method according to claim 1 , wherein the regular light-emitting lattice is arranged into a square shape, a rectangular shape, a circular shape, or a triangular shape.
4. The method according to claim 1 , wherein the coding rule is a space coding method or a time-space coding method.
5. A time-space coding apparatus for generating a structured light coded pattern, comprising:
a light-emitting substrate;
a collimator;
a driving module; and
a display control module, wherein
a plurality of regularly arranged light-emitting particle elements are distributed on the light-emitting substrate;
the collimator performs collimation processing to light rays emitted by all of the light-emitting particle elements on the light-emitting substrate;
the driving module is configured for driving the regularly arranged light-emitting particle elements on the light-emitting substrate with constant current in an X-Y axis direction; and
the display control module selects, in accordance with a coding rule, light-emitting particle elements that meet the coding rule and informs the driving module to drive for displaying the selected light-emitting particle elements.
6. The apparatus according to claim 5 , further comprising:
a diffractive optical element (DOE) that duplicates, arranges, and further splices a coded pattern emitted by the light-emitting substrate.
7. The apparatus according to claim 5 , wherein the light-emitting substrate is of a square shape, a rectangular shape, a circular shape, or a triangular shape.
8. The apparatus according to claim 5 , wherein the display control module separately controls individual light emitting particle elements, each light emitting particle element has a corresponding switching signal and current intensity signal; or a plurality of light emitting particle elements can be subject to uniform control, a plurality of light emitting particle elements in a same group have a same switching signal and current intensity signal so as to be either simultaneously turned on or simultaneously turned off.
9. The apparatus according to claim 5 , wherein the display control module comprises an external communication interface via which a user controls on and off of each light emitting particle element on the light emitting substrate or adjusts a light emitting brightness, thereby generating different shapes of coded patterns designed by a user.
10. The apparatus according to claim 5 , wherein the display control module cannot only control projection of a fixed coded pattern to label the space object, but also can control time-division output of a plurality of different coded patterns, thereby time-space labelling the target object or projection space.