Patent ID: 11922262
Assignee: CHANGXIN MEMORY TECHNOLOGIES, INC.
Field: Computer technology (Electrical engineering)
Classification: CPC G | IPC G

Claim 0:
1. A photomask inspection system, comprising:
a thickness measuring device for a photomask, comprising a plurality of sensor modules arranged side by side, wherein the plurality of sensor modules measures a thickness of the photomask;
a barcode reading device, configured to read a barcode on the photomask to obtain the thickness of the photomask, wherein the barcode reading device and the thickness measuring device are disposed opposite to each other; and
a calibration device, configured to calibrate the barcode reading device, wherein the calibration device comprises a calibration rod and an electromagnet, wherein the calibration rod comprises a calibration stick and a calibration base, and wherein the electromagnet is arranged at a bottom of the calibration base.