Random laser speckle based modulation transfer function measurement of midwave infrared focal plane arrays

Kenneth J. Barnard; Igor Anisimov; John E. Scheihing

doi:10.1117/1.OE.51.8.083601

2 August 2012 Random laser speckle based modulation transfer function measurement of midwave infrared focal plane arrays

Kenneth J. Barnard, Igor Anisimov, John E. Scheihing

Author Affiliations +

Optical Engineering, Vol. 51, Issue 8, 083601 (August 2012). https://doi.org/10.1117/1.OE.51.8.083601

Abstract

Direct measurement of the modulation transfer function (MTF) of focal plane arrays (FPAs) using random laser speckle approaches for the visible/near-infrared wavelength band has been well documented over the last 20 years. These methods have not transitioned to the midwave infrared (MWIR) primarily because other techniques have been sufficient and MWIR laser sources with sufficient output power have been unavailable. However, as the detector pitch decreases, MTF measurements become more difficult due to diffraction, while potential MTF degradation due to lateral carrier diffusion crosstalk makes accurate MTF characterization critical for sensor system design. Here, a random laser speckle FPA MTF measurement approach is adapted for use in the MWIR that utilizes a quantum cascade laser coupled with an integrating sphere to generate the appropriate in-band random speckle. Specific challenges associated with the technique are addressed including the validity of the Fresnel diffraction assumptions describing the propagation of the random speckle field from the integrating sphere to the FPA. Improved methods for estimating the power spectral density (PSD) of the measured speckle that reduce data requirements are presented. The statistics and uniformity of the laser speckle are presented along with PSD measurements and estimated MTFs of a MWIR FPA.

Citation Download Citation

Kenneth J. Barnard, Igor Anisimov, and John E. Scheihing "Random laser speckle based modulation transfer function measurement of midwave infrared focal plane arrays," Optical Engineering 51(8), 083601 (2 August 2012). https://doi.org/10.1117/1.OE.51.8.083601

Published: 2 August 2012

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