%0 Journal Article
%T Mid-Infrared Lifetime Imaging for Viability Evaluation of Lettuce Seeds Based on Time-Dependent Thermal Decay Characterization
%A Ghiseok Kim
%A Geon Hee Kim
%A Chi-Kook Ahn
%A Yoonkyu Yoo
%A Byoung-Kwan Cho
%J Sensors
%D 2013
%I MDPI AG
%R 10.3390/s130302986
%X An infrared lifetime thermal imaging technique for the measurement of lettuce seed viability was evaluated. Thermal emission signals from mid-infrared images of healthy seeds and seeds aged for 24, 48, and 72 h were obtained and reconstructed using regression analysis. The emission signals were fitted with a two-term exponential model that had two amplitudes and two time variables as lifetime parameters. The lifetime thermal decay parameters were significantly different for seeds with different aging times. Single-seed viability was visualized using thermal lifetime images constructed from the calculated lifetime parameter values. The time-dependent thermal signal decay characteristics, along with the decay amplitude and delay time images, can be used to distinguish aged lettuce seeds from normal seeds.
%K mid-infrared thermography
%K thermal lifetime image
%K nondestructive test
%K lettuce seed
%K seed viability
%U http://www.mdpi.com/1424-8220/13/3/2986