A Novel Light Routing Device with Phase Encoding using Liquid Crystal Spatial Light Modulator

一种采用液晶空间光调制器的相位编码新型光路由装置

基本信息

批准号：
09650387
负责人：
KANNARI Fumihiko
金额：
$ 1.98万
依托单位：
Department of Electrical Engineering, Faculty of Science and Technology, Keio University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

项目摘要

A novel space variant optical interconnection, where the spatial routing pattern among nodes is variable only by changing the phase encoding pattern embedded on a spatial light modulator (SLM), is proposed and experimentally examined its basic performance for one-dimensional routing patterns. The spatial phase profile of a coherent light is shaped with a segmented liquid crystal SLM so that the far-field pattern matches to a desired routing pattern. At the same time, the laser beam is encoded with a M-series code and converted to a quasi noise spatial pattern. Various routing patterns encoded with different M-series are multiplexed and send in space. At a receiver, only a desired routing pattern can be selected with an identical M-series phase mask. The rest of multiplexed signals remain as noise and eliminated by some threshold detectors. We obtained following conclusions through theoretical and experimental studies.(1) Assuming a 128x128 segmented SLM at 16 gray levels, one can multiplex more than 100 routing patterns using length-127 M-series phase codes.(2) Proof-of-concept experiments was conducted with a 128 one-dimensional SLM and a HeNe laser. Doubly encoded spatial routing pattern embedded on the SLM was successfully decoded with another SLM phase mask. The signal-to-loss ratio were evaluated for different M-series code lengths.(3) We demonstrated that a spatial pattern encoded for the spectral phase of an incoherent light can be sent through a fiber and recovered by forming a spectral holography. This time-to-space conversion scheme can open up new optical interconnections and communications.(4) In order to use spectral holography technologies in fiber delivered interconnections and communications, we demonstrated holography at 1.3mm wavelength. The hologram was first written by a SHG of 1.3mm laser and then read by the fundamental beam.

一种新型的空间变体光学互连，其中节点之间的空间路由模式仅通过更改空间光调制器（SLM）上的相位编码模式（SLM）而变化，并通过实验检查了其对一维路由模式的基本性能。相干光的空间相位曲线用分段的液晶SLM形成，因此远场图案与所需的路由图案匹配。同时，用M系列代码编码激光束并转换为准噪声空间图案。用不同M系列编码的各种路由模式是多路复用并发送空间的。在接收器处，只能使用相同的M系相掩码选择所需的路由模式。其余的多重信号保持为噪声，并被一些阈值检测器消除。我们通过理论和实验研究得出了以下结论。（1）假设在16个灰度处采用128x128分段的SLM，可以使用长度为127 M系列代码多重多重超过100个路由模式。（2）使用128个一维SLM和hene hene laser进行了概念验看实验。嵌入在SLM上的双重编码的空间路由模式已成功用另一个SLM相掩码解码。评估了不同的M系列代码长度的信噪比。（3）我们证明，可以通过纤维发送针对不一致光的光谱阶段编码的空间模式，并通过形成光谱全息恢复。该时间空间转换方案可以打开新的光学互连和通信。（4）为了在光纤传递的互连和通信中使用光谱全息技术，我们在1.3mm波长下证明了全息图。全息图最初是由1.3毫米激光的SHG编写的，然后由基本梁读取。