Measuring the lens focal length by laser confocal technique

Hualing Wu; Jiamiao Yang; Liurong Qiu; Weiqian Zhao

doi:10.1117/12.2035803

10 October 2013 Measuring the lens focal length by laser confocal technique

Hualing Wu, Jiamiao Yang, Liurong Qiu, Weiqian Zhao

Proceedings Volume 8916, Sixth International Symposium on Precision Mechanical Measurements; 89161E (2013) https://doi.org/10.1117/12.2035803
Event: Sixth International Symposium on Precision Mechanical Measurements, 2013, Guiyang, China

Abstract

A new laser confocal focal-length measurement (LCFM) is proposed for the high-accuracy measurement of lens back focal length. LCFM uses the peak point of confocal response curve to precisely identify the lens focus, and uses the elastic contact between reflector R and the lens last surface to determine the test lens last vertex. The distance between the reflectors on these two positions is then measured by a laser distance interferometer, and then the accurate back focal-length of test lens is obtained. Compared with existing methods, LCFM significantly improves the measurement accuracy and simplifies the system structure by laser confocal technique, and reduces the product development cost. LCFM is especially suitable for the back focal-length measurement of large aperture lens.

Citation Download Citation

Hualing Wu, Jiamiao Yang, Liurong Qiu, and Weiqian Zhao "Measuring the lens focal length by laser confocal technique", Proc. SPIE 8916, Sixth International Symposium on Precision Mechanical Measurements, 89161E (10 October 2013); https://doi.org/10.1117/12.2035803

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available