Two-dimensional measurement of the lens optical transfer function from a digital image

David P. Morgan-Mar; Matthew R. Arnison; Chris A. Deller; Peter A. Fletcher; Kieran G. Larkin

doi:10.1117/12.871897

24 January 2011 Two-dimensional measurement of the lens optical transfer function from a digital image

David P. Morgan-Mar, Matthew R. Arnison, Chris A. Deller, Peter A. Fletcher, Kieran G. Larkin

Proceedings Volume 7876, Digital Photography VII; 78760H (2011) https://doi.org/10.1117/12.871897
Event: IS&T/SPIE Electronic Imaging, 2011, San Francisco Airport, California, United States

Abstract

We present a novel method for accurately measuring the optical transfer function (OTF) of a camera lens by digitally imaging a tartan test pattern containing sinusoidal functions with multiple frequencies and orientations. The tartan pattern can be tuned to optimize the measurement accuracy for an adjustable set of sparse spatial frequencies. The measurement method is designed to be accurate, reliable, and fast in a wide range of measurement conditions, including uncontrolled lighting. We describe the design of the tartan pattern and the algorithm for estimating the OTF accurately from a captured digital image. Simulation results show that the tartan method has significantly better accuracy for measuring the modulus of the OTF (the modulation transfer function, or MTF) than the ISO 12233 standard slanted-edge method, especially at high spatial frequencies. With 1% simulated imaging noise, the root mean square (RMS) error of the tartan method is on average 5 times smaller than the RMS error of the slanted-edge method. Experiments with a printed tartan chart show good agreement (0.05 RMS) with MTFs measured using the slanted-edge method and that, like the slanted-edge method, our method is tolerant to wide variations in illumination conditions.

Citation Download Citation

David P. Morgan-Mar, Matthew R. Arnison, Chris A. Deller, Peter A. Fletcher, and Kieran G. Larkin "Two-dimensional measurement of the lens optical transfer function from a digital image", Proc. SPIE 7876, Digital Photography VII, 78760H (24 January 2011); https://doi.org/10.1117/12.871897

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