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Updated: Feb 14, 2026

Simulation of Early Earth Hydrothermal Chimneys in a Thermal Gradient Environment
Published on: February 27, 2021
IR-to-visible image upconverter under nonlinear crystal thermal gradient operation
Abstract:
In this work we study the enhancement of the field-of-view of an infrared image up-converter by means of a thermal gradient in a PPLN crystal. Our work focuses on compact upconverters, in which both a short PPLN crystal length and high numerical aperture lenses are employed. We found a qualitative increase in both wavelength and angular tolerances, compared to a constant temperature upconverter, which makes it necessary a correct IR wavelength allocation in order to effectively increase the up-converted area.
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