title: Nonlinearity Measurements of High-Power Laser Detectors at NIST.
abstract: We briefly explain the fundamentals of detector nonlinearity applicable to both electrical and optical nonlinearity measurements. We specifically discuss the attenuation method for optical nonlinearity measurement that the NIST system is based upon, and we review the possible sources of nonlinearity inherent to thermal detectors used with high-power lasers. We also describe, in detail, the NIST nonlinearity measurement system, in which detector responsivity can be measured at wavelengths of 1.06 µm and 10.6 µm, over a power range from 1 W to 1000 W. We present the data processing method used and show measurement results depicting both positive and negative nonlinear behavior. The expanded uncertainty of a typical NIST high-power laser detector calibration including nonlinearity characterization is about 1.3 %.
authors.affiliation: National Institute of Standards and Technology, Boulder, CO 80305.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Li
authors.affiliation: National Institute of Standards and Technology, Boulder, CO 80305.
authors.forename: Thomas
authors.initials: T
authors.lastname: Scott
authors.affiliation: National Institute of Standards and Technology, Boulder, CO 80305.
authors.forename: Shao
authors.initials: S
authors.lastname: Yang
authors.affiliation: National Institute of Standards and Technology, Boulder, CO 80305.
authors.forename: Chris
authors.initials: C
authors.lastname: Cromer
authors.affiliation: National Institute of Standards and Technology, Boulder, CO 80305.
authors.forename: Marla
authors.initials: M
authors.lastname: Dowell
keywords: attenuation method; calibration; calorimeter; chopper wheel; high-power laser; nonlinearity measurement; thermal detector