US 12,188,794 B1
Grating displacement measurement device and method using double-layer floating reading head, medium, and apparatus
Wenhao Li, Changchun (CN); Wenyuan Zhou, Changchun (CN); Zhaowu Liu, Changchun (CN); Shan Jiang, Changchun (CN); Wei Wang, Changchun (CN); Yujia Sun, Changchun (CN); Lin Liu, Changchun (CN); Xu Liang, Changchun (CN); and Siyu Jin, Changchun (CN)
Assigned to Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun (CN)
Filed by Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun (CN)
Filed on Sep. 20, 2024, as Appl. No. 18/891,376.
Claims priority of application No. 202311356408.8 (CN), filed on Oct. 19, 2023.
Int. Cl. G01D 5/26 (2006.01)
CPC G01D 5/266 (2013.01) 8 Claims
OG exemplary drawing
 
1. A grating displacement measurement device using a double-layer floating reading head, comprising:
a substrate having a substrate working surface, wherein the substrate working surface is arranged on a top of the substrate, the substrate working surface has at least two first side edges opposite to each other and at least two second side edges opposite to each other, the first side edges are adjacent to the second side edges, the at least two first side edges extend in a first direction, the at least two second side edges extend in a second direction perpendicular to the first direction, a center line of the substrate working surface extending in the first direction is a first reference line, and a center line of the substrate working surface extending in the second direction is a second reference line;
a light-through member, wherein the light-through member has a light-through hole facing a center point of the substrate working surface;
a first measurement grating group comprising two first measurement gratings, wherein the two first measurement gratings are provided on the substrate working surface and symmetrically arranged on both sides of the first reference line, and each first measurement grating is arranged parallel to the first side edge;
a second measurement grating group comprising two second measurement gratings, wherein the two second measurement gratings are provided above the substrate working surface and symmetrically arranged on both sides of the first reference line, a center line of the second measurement grating extending in the second direction coincides with the second reference line, the light-through member is arranged between the two second measurement gratings, and one of the second measurement gratings is arranged on the same side of the first reference line as one of the first measurement gratings;
a reading component group comprising at least two reading components, wherein each reading component is arranged between the first measurement grating and the second measurement grating located on the same side of the first reference line, and each reading component is configured to collect a first position information of the first measurement grating and a second position information of the second measurement grating; and
a control unit electrically connected to the reading component group, wherein the control unit is configured to generate a first position parameter according to the first position information, generate a second position parameter according to the second position information, and calculate a third position parameter of the substrate working surface according to the first position parameter and the second position parameter.