Matwyschuk Alexis
Appl Opt. 2017 Sep 20;56(27):7766-7773. doi: 10.1364/AO.56.007766.
Having laid down previously the foundations of the multiple-wavelength range-gated active imaging (WRAI) principle in flash mode and accumulation mode, its use in superimposed style for the direct tracking of moving objects was studied. The movement is supposed to be in a transverse plane of the scene. Each emitted laser pulse with a different wavelength visualizes the object at a specific time. Therefore, the wavelength set allows us to freeze the different positions of the object in the recorded image according to the laser emission period. Thus, in each recorded image, the object trajectory can be visualized directly according to these specific moments, allowing us to deduce the speed and the acceleration of the object at the same time. Another advantage, especially when the object trajectory is unpredictable, is that the wavelength progression indicates the trajectory direction. The principle being independent of the video frequency, the object speed can be very high. Furthermore, the range gating allows improvement of the object visibility through scattering environments. Three cases were identified and studied in superimposed style. Although the first case has not been used with range gating, it allowed us to show the possibility of using a traditional color camera. On the other hand, the two cases applying range gating required management of the exposure time. In each case, the temporal behavior was studied, as well as the possible speeds according to the object distance. The experimental test results validated the theoretical part and the possibility to determine the trajectory and the speed of a moving object with the WRAI principle in superimposed style.
在奠定了多波长距离选通主动成像（WRAI）原理在闪光模式和累积模式下的基础之后，研究了其在叠加模式下用于直接跟踪移动物体的情况。假设物体的运动是在场景的横向平面内。每个发射的具有不同波长的激光脉冲在特定时间使物体成像。因此，波长组使我们能够根据激光发射周期在记录图像中冻结物体的不同位置。这样，在每个记录图像中，可以根据这些特定时刻直接可视化物体轨迹，从而使我们能够同时推断出物体的速度和加速度。另一个优点，特别是当物体轨迹不可预测时，是波长顺序指示轨迹方向。该原理与视频频率无关，物体速度可以非常高。此外，距离选通可以通过散射环境提高物体的可见性。在叠加模式下确定并研究了三种情况。虽然第一种情况未与距离选通一起使用，但它使我们能够展示使用传统彩色相机的可能性。另一方面，应用距离选通的两种情况需要管理曝光时间。在每种情况下，都研究了时间行为以及根据物体距离的可能速度。实验测试结果验证了理论部分以及使用叠加模式下的WRAI原理确定移动物体轨迹和速度的可能性。
