We demonstrate a prototype for a compact, hybrid daylight harvesting system that collects and transports sunlight to illuminate dark spaces, up to two levels underground. The prototype is designed to have a compact size so that it can be mounted on top of a conventional lamp post at ground level and the system serves an additional purpose of a streetlamp for ground level illumination during nighttime. The system utilizes an acrylic ball lens as solar concentrator, and the focused sunlight is directly coupled into a single plastic optical fiber that transports it to indoor spaces. The spherical symmetry of the ball lens allows it to be static, while the position of focused light spot varies gradually underneath it, in accordance with the solar position in the sky. Therefore, only the light-collecting optical fiber needs to be moved under the ball lens, obviating the need for heavy-duty motors typically used to align solar concentrators along the direction of sun’s rays. The focused sunlight under the ball is tracked using a microcontroller-based tracking mechanism. This design is the first demonstration of a daylight harvesting system, to the best of our knowledge, using a ball lens as static sunlight collector and a movable optical fiber tracking the focused spot underneath the ball. The moving parts in the proposed system are lightweight and are well concealed from environmental hazards like dust, wind and moisture.

我们演示了一种紧凑型混合日光采集系统的原型，该系统可以收集和传输阳光以照亮黑暗的空间，地下空间最多可达两层。该原型设计为具有紧凑的尺寸，因此可以在地面上安装在常规灯柱的顶部，并且该系统还可以用作路灯的夜间用途，以在夜间进行地面照明。该系统利用丙烯酸球镜作为太阳能聚光器，聚焦的阳光直接耦合到单个塑料光纤中，该塑料光纤将其传输到室内空间。球形透镜的球面对称性使其可以保持静止，而聚焦光斑的位置则根据其在天空中的太阳位置逐渐在其下方变化。因此，仅需将集光光纤移动到球镜下方，就无需使用通常用于将聚光器沿太阳光线方向对准的重型电机。使用基于微控制器的跟踪机制跟踪球下聚焦的阳光。就我们所知，此设计是日光收集系统的首次演示，它使用球镜作为静态阳光收集器，并使用可移动的光纤跟踪球下方的聚焦点。拟议系统中的活动部件重量轻，并且很好地掩盖了诸如灰尘，风和湿气之类的环境危害。使用基于微控制器的跟踪机制跟踪球下聚焦的阳光。就我们所知，此设计是日光收集系统的首次演示，它使用球镜作为静态阳光收集器，并使用可移动的光纤跟踪球下方的聚焦点。拟议系统中的活动部件重量轻，并且很好地掩盖了诸如灰尘，风和湿气之类的环境危害。使用基于微控制器的跟踪机制跟踪球下聚焦的阳光。就我们所知，此设计是日光收集系统的首次演示，它使用球镜作为静态阳光收集器，并使用可移动的光纤跟踪球下方的聚焦点。拟议系统中的活动部件重量轻，并且很好地掩盖了诸如灰尘，风和湿气之类的环境危害。