Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group

Line-scanning laser scattering system for fast defect inspection of a large aperture surface

Not Accessible

Your library or personal account may give you access

Abstract

Inspection of defects with micrometer level on large aperture surfaces with hundreds of millimeters is one of the challenges in surface quality evaluation. Various microscopic imaging methods have been applied to inspecting the surface defects, while they are time-consuming for the small field of view and the sub-aperture stitching. To tackle this problem, a high-speed line scanning system based on the dark-field laser scattering method is proposed. The laser beam is scanned by the rotating polygon mirror to a laser line for high throughput and then the telecentric F-theta lens converges each incoming laser beam to a focused spot that creates a high intensity to enhance the signal-to-noise ratio. The scattered light from surface defect is collected by the designed integrating sphere for low background noise and the scattering signal is detected for each focused spot at a proper acquisition rate by a photomultiplier (PMT) detector with extremely short response time. In the meanwhile, the tested surface is moving perpendicular to the laser line to realize high-speed large area inspection. The defect inspection system is confirmed experimentally with laser line length of 60 mm, minimum detectable size less than 0.5 μm, and figure of merit of 9.6cm2s1μm1. The work put forward an effective method for automatic discovery of surface defects such as scratches, digs, and contaminants on large aperture surfaces.

© 2017 Optical Society of America

Full Article  |  PDF Article
More Like This
Vision system with high dynamic range for optical surface defect inspection

Zhaolou Cao, Fenping Cui, and Chunjie Zhai
Appl. Opt. 57(34) 9981-9987 (2018)

Aperture design for a dark-field wafer defect inspection system

Chao Liu, Shuang Xu, Yufei Liu, and Zainan Xiao
Appl. Opt. 60(35) 10830-10837 (2021)

Defects evaluation system for spherical optical surfaces based on microscopic scattering dark-field imaging method

Yihui Zhang, Yongying Yang, Chen Li, Fan Wu, Huiting Chai, Kai Yan, Lin Zhou, Yang Li, Dong Liu, Jian Bai, and Yibing Shen
Appl. Opt. 55(23) 6162-6171 (2016)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Figures (12)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Tables (2)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Equations (7)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved