Abstract

Wavelength up-conversion [1] to the visible spectrum of eye-safe images around 1550 nm is useful for applications in biomedical imaging and homeland security. Due to the better performance of Silicon Focal Plane Array (FPA) imaging sensors like CCD or CMOS or image intensier tubes as compared to InGaAs Short Wave Infrared FPA sensors, up-conversion of infrared images to the visible is advantageous in some applications that require high resolution, high gating speed, or uncooled cameras. Intracavity up-conversion in solid state lasers provides a convenient resource for this purpose [2]. The system is based on sum-frequency mixing of the infrared image with a gausian laser beam at 1064 nm inside the cavity of a diode-pumped GdVO₄:Nd³⁺ laser that contains a periodically poled lithium niobate crystal (PPLN), resulting in a 631 nm up-converted image.

© 2015 IEEE