为了证明远红外电视系统的可用性,瑞典Chalmers工艺大学的有关工作人员已用脉冲-位置调制把电视信号强加到铅盐半导体激光器的光束上。光束用透镜集聚并用光伏铅盐探测器探测。然后使视频信号从探测器输出解调并耦合到电视监控器上。他们发现通过实验室发射的象上没有雪花干扰,这表示了良好的信噪比。然而,他们注意到即 To prove the availability of far-infrared television systems, staff at Chalmers University of Technology in Sweden have used pulse-position modulation to impose television signals onto the beam of a lead salt semiconductor laser. The beam is collected with a lens and probed with a photo lead salt detector. The video signal is then demodulated from the detector output and coupled to the television monitor. They found that there was no snow interference on the image emitted by the laboratory, which showed a good signal-to-noise ratio. However, they noticed that