I= DIGITAL OPTICAL COMPUTING USING POLARIZATION ENCODED OPTICAL SHADOW-CASTING TECHNIQUE
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Title of Thesis
DIGITAL OPTICAL COMPUTING USING POLARIZATION ENCODED OPTICAL SHADOW-CASTING TECHNIQUE

Author(s)
S. Rizwan Ali Rizvi
Institute/University/Department Details
Department of Physics/ Quaid-i-Azam University, Islamabad
Session
1994
Subject
Physics
Number of Pages
168
Keywords (Extracted from title, table of contents and abstract of thesis)
digital optical computing, optical shadow-casting technique, combinational logic circuits, sequential logic circuits, polarization-encoded optical shadow-casting, posc, lensless shadow-casting technique, full adder design, trinary logic, nonclocked flip-flops, clocked latches

Abstract
A digital electronic computer consists of two types of circuits, combinational and sequential logic circuits. The building blocks of combinational logic circuits are binary logic gates which act as the switching elements in a digital computer. The sequential circuits, on the other hand, are implemented by using flip-flops which act as the memory elements. In this thesis these basic most logic elements are designed and implemented optically for a digital optical processor based on the polarization-encoded optical shadow-casting (POSC) technique.

Binary optical decoders have been designed in POSC scheme by using the POSC modified algorithm. The exclusive aspect of this design is that the multioutputs are always generated separately and simultaneously at the output plane. In particular a 3-to-8 line decoder and a BCD to an excess-3 code converter have been developed The scope of multiple valued logic is explored in general and particularly in optics based computing. Moreover the design and implementation of some trinary combinational logic elements is presented in POSC scheme.

In the end we have proposed a novel POSC scheme to optically implement different types of sequential logic elements. The proposed system architecture is capable of implementing synchronous as well as asynchronous sequential circuits. The design and implementation of various flip-flops has been presented. The main features of these flip-flops is that various sequential operations are performed optically by utilizing optical feedback.

Download Full Thesis
1157.18 KB
S. No. Chapter Title of the Chapters Page Size (KB)
1 0 Contents 0
77.76 KB
2 1 Introduction 1
160.42 KB
  1.1 Limitations of Electronic Computer 2
  1.2 Advantages of Optics 5
  1.3 Trends in Digital Optical Computing 6
  1.4 Lensless Shadow-Casting Technique 9
  1.5 Layout of Thesis 17
3 2 Polarization Encoded Optical Shadow-Casting Scheme 20
114.27 KB
  2.1 Polarization Encoded optical Shadow-Casting System 21
  2.2 Implementation of Combinational Logic units 25
  2.3 The POSC Modified Algorithm 26
  2.4 Full Adder Design 29
  2.5 Conclusion 37
4 3 Design Of Optical Decoders Using Polarization Encoded Optical Shadow-Casting Scheme 38
86.58 KB
  3.1 Decoders 39
  3.2 Code Converters 46
  3.3 Conclusion 50
5 4 Implementation Of Trinary Logic In Polarization Encoded Optical Shadow-casting Scheme 53
168.3 KB
  4.1 Multiple Valued Logic and Optical Computing 53
  4.2 Half-Adder and Half- subtracter Design 55
  4.3 Full-Adder and Full- Subtracter Design 62
  4.4 Experimental Verification 72
  4.5 Conclusion 75
6 5 Optical Flip-Flops in POSC Scheme 77
188.94 KB
  5.1 Optical Flip-Flops 77
  5.2 System configuration 80
  5.3 Design Algorithm 82
  5.4 Nonclocked Flip-Flops 86
  5.5 Clocked Latches 97
  5.6 Conclusion 104
7 6 References 107
555.92 KB