US 12,215,967 B2
Line-scanning three-dimensional sensing system
Jinbo Jiang, Hong Kong (CN); Steaphan Si Fan Xie, Hong Kong (CN); and Yong Chi, Hong Kong (CN)
Assigned to Hong Kong Applied Science and Technology Research Institute Company Limited, Hong Kong (CN)
Filed by Hong Kong Applied Science and Technology Research Institute Company Limited, Hong Kong (CN)
Filed on Aug. 12, 2022, as Appl. No. 17/819,340.
Prior Publication US 2024/0053140 A1, Feb. 15, 2024
Int. Cl. G01B 11/25 (2006.01); G02B 27/09 (2006.01)
CPC G01B 11/25 (2013.01) [G02B 27/0955 (2013.01); G02B 27/0988 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A line-scanning three-dimensional (3D) sensing system for measuring a surface profile of an object, the system comprising:
a light source module for generating a polychromatic light beam, wherein the light source module is a color-mixing light source module comprising:
a light source for generating raw light rays that collectively provide polychromatic light; and
a color mixing rod optically coupled to the first slit to provide the polychromatic light beam to the first slit for spatial filtering, the color mixing rod being shaped as an elongated slab for mixing the raw light rays to generate the polychromatic light beam such that at least a portion of the polychromatic light beam to be received by the first slit is substantially uniform in color;
a first slit for spatially filtering the polychromatic light beam to form a polychromatic linear light beam (PLLB);
a dispersion optical module (DOM) configured to:
perform a forward optical process of chromatically dispersing the PLLB received from the first slit into constituent narrowband linear light beams (CNLLBs) and focusing the CNLLBs respectively on different focal planes to form a rainbow light pattern for illuminating a scanned surface of the object during surface profile measurement, whereby the illuminated object is caused to display an information-bearing color image (IBCI) on the object, the IBCI containing height information of the scanned surface;
capture the IBCI; and
perform a backward optical process of optically condensing the captured IBCI to form an elongated light pattern, wherein the backward optical process is an inverse of the forward optical process;
and
a second slit for spatially filtering the elongated light pattern to form an output light line, whereby a height profile of the scanned surface is obtainable by analyzing a spectral content at each point of the output light line such that the surface profile is determinable according to respective height profiles obtained for a plurality of scanned surfaces of the object.