摘要 |
A back scatter absorption detector/imager having an optical parametric device for generating sensing radiation, the optical parametric device having a nonlinear medium (NLC) and a pump wave laser source, the nonlinear medium (NLC) being able to generate a signal and an idler wave in response to being stimulated with the pump wave, thereby to generate sensing radiation, and a detector (D) for detecting any sensing radiation back-scattered from a target area, characterized in that the pump wave laser source and the nonlinear medium (NLC) are provided in the same optical cavity. |