Optical Society of America Publishing
In a recently demonstrated algorithmic spectral-tuning technique by Jang et al. [Opt. Express 19, 19454-19472, (2011)], the reconstruction of an object’s emissivity at an arbitrarily specified spectral window of interest in the long-wave infrared region was achieved. The technique relied upon forming a weighted superposition of a series of photocurrents from a quantum dots-in-a-well (DWELL) photodetector operated at discrete static biases that were applied serially. Here, the technique is generalized such that a continuously varying biasing voltage is employed over an extended acquisition time, in place using a series of fixed biases over each sub-acquisition time, which totally eliminates the need for the post-processing step comprising the weighted superposition of the discrete photocurrents. To enable this capability, an algorithm is developed for designing the time-varying bias for an arbitrary spectral-sensing window of interest. Since continuous-time biasing can be implemented within the readout circuit of a focal-plane array, this generalization would pave the way for the implementation of the algorithmic spectral tuning in focal-plane arrays within in each frame time without the need for on-sensor multiplications and additions. The technique is validated by means of simulations in the context of spectrometry and object classification while using experimental data for the DWELL under realistic signal-to-noise ratios.
Jang, Woo-Yong; Hayat, Majeed M.; Zarkesh-Ha, Payman; and Krishna, Sanjay, "Continuous time-varying biasing approach for spectrally tunable infrared detectors" (2012). Electrical and Computer Engineering Faculty Research and Publications. 570.
ADA Accessible version
Accepted version. Optics Express, Vol. 20, No. 28 (2012): 29823-29837. DOI. This article is © 2012 Optical Society of America Publishing. Used with permission.
Majeed M. Hayat was affiliated with University of New Mexico, Albuquerque at the time of publication.