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1.
刘立人  张子北 《光学学报》1993,13(10):08-912
基于多重成像原理,在本文中提出一种光学并行图像逻辑处理系统。对输入图案用两个正像和两个补偿进行编码。通过光调制器控制,可以实现逻辑操作的实时可编程。而且,该系统可以通过控制一组四个偏振片的状态实现独立的双输出逻辑通道,每一个输出通道各有十六种逻辑功能。文中也给出了实验结果。  相似文献   

2.
In this work, a three-step modified signed-digit (MSD) addition by using binary logic operations is proposed. Each input digit is encoded with two binary bits. Through binary logic operations, all of the weight and transfer digits and the final sum digits represented with the same encoding scheme will be generated. The operations can be performed at each digit position in parallel. In our suggested optical arithmetic and logic unit (ALU), a single electron trapping (ET) device is employed to serve as the binary logic device. This technique based on ET logic possesses the advantage of high signal-to-noise ratio (SNR). The optoelectronic system can be constructed in a simple, compact and general-purpose form.  相似文献   

3.
Conventional algorithms process addition and subtraction in different ways. In this paper, by introducing bipolar carries, a unified negabinary symbolic arithmetic for the two operations can be derived, using only the same six substitution rules. Based on the polarization-encoded optical shadow-casting technique, the encoding and decoding patterns for half-addition, half-subtraction and unified arithmetic are designed, with the fixed LED pattern and separate and simultaneous generation of the multi-outputs. The architecture is simple, programmable, cost-efficient, and the addition and subtraction of multiple pairs of bipolar numbers can be handled in parallel in the same manner.  相似文献   

4.
We propose here a new optical modified signed-digit (MSD) adder module based on bit plane pattern encoding of MSD digits and pattern operations. The pattern operations required in the algorithm are duplication, combination and shifting. They are simply performed by using optical components such as beam splitters, mirrors and parallel plates, instead of optical logic arrays. An optical MSD adder module comprised of six properly interacting blocks with all optical components packaged on a common substrate is presented in detail. We analyze the system errors caused by manufacture and alignment of optical components, the information throughput, the intensity nonuniformity and the system volume of the adder module.  相似文献   

5.
可编程光学并行模糊逻辑门   总被引:1,自引:0,他引:1  
张树群  陈彩生 《光学学报》1994,14(12):341-1344
提出了可级联的光学并行模糊逻辑门系统,十六种模糊逻辑运算可通过编程偏振半波片的状态而得到实现,语言中给出了实验结果。  相似文献   

6.
Sisir Kumar Garai 《Optik》2010,121(16):1462-3807
Optics has already proved its strong potential in information and data processing because of its inherent parallelism. Several all-optical data processors were proposed since the last few decades. Again it is also known that tristate operations can be well accommodated with optics in data and information processing, as this type of operation can enhance the information quality and capacity. Very recently, the concept of frequency variant encoding /decoding technique has been established because of its basic advantages. The potential advantage of frequency-dependent encoding/decoding is that, as the frequency is the fundamental character of a signal, it will remain unaltered in reflection, refraction, absorption, etc. during transmission. In this communication, the authors therefore propose a method of implementing frequency-encoded inversion logic operations with tristate logic using reflecting semiconductor optical amplifiers (RSOA).  相似文献   

7.
In conduction of parallel logic, arithmetic and algebraic operations, optics has already proved its successful role. Since last few decades a number of established methods on optical data processing were proposed and to implement such processors different data encoding/decoding techniques have also been reported. Currently frequency encoding technique is found be a promising as well as a faithful mechanism for the conversion of all-optical processing as the frequency of light remains unaltered after refection, refraction, absorption, etc. during the transmission of light. There are already proposed some frequency encoded optical logic gates. In this communication the authors propose a new and different concept of frequency encoded optical logic gates and optical flip-flop using the non-linear function of semiconductor optical amplifier.  相似文献   

8.
Sisir Kumar Garai 《Optik》2010,121(8):715-721
Optics has already been proved its successful roles for conduction of parallel logic, arithmetic and algebraic operations. Since last few decades many types of optical data processors were proposed. To implement these processors different data encoding/decoding techniques have been reported. In this context polarization encoding technique, tristate, quartenary logic, multivalued logic, symbolic substitution techniques etc. may be mentioned. Very recently, frequency encoding/decoding technique have also been well established. The potential advantage of frequency dependent encoding/decoding is that, as the frequency being the fundamental character of a signal; it will remain unaltered in reflection, refraction, absorption etc. during transmission of the signal. In this communication the authors propose a scheme for implementing different logic operations adopting frequency based encoding technique. For this purpose the second harmonic generation and difference frequency generation techniques are used by exploiting the non-linear response character of some materials.  相似文献   

9.
Optics has already proved its strong potentiality for the conduction of parallel logic, arithmetic and algebraic operations. In the last few decades several all-optical data processors were proposed. To implement these processors different data encoding/decoding techniques have been reported. In this context, polarization encoding technique, intensitybased encoding technique, tristate and quaternary logic operation, multivalued logic operations, symbolic substitution techniques etc. may be mentioned. Very recently, frequency encoding/decoding technique has drawn interest from the scientific community. Frequency is the fundamental character of any signal; and it remains unaltered in reflection, refraction, absorption etc. during the propagation and transmission of the signal. This is the most important advantage of frequency encoding technique over the conventional encoding techniques. In this communication the authors propose a new scheme for implementing NOT, OR and NOR logic operations. For this purpose co-propagating beams having different frequencies in C-band (1535–1560 nm) have been used for generating cascaded sum and difference frequency, exploiting the nonlinear response character of periodically poled LiNbO3 waveguide. The cross-gain modulation property of the semiconductor optical amplifier (SOA) and the wavelength conversion property of the reflecting semiconductor optical amplifiers (RSOA) are exploited here to implement the desired optical logic and arithmetic operations.  相似文献   

10.
光学并行实现模糊逻辑图像处理   总被引:2,自引:2,他引:0  
景红梅  刘立人 《光学学报》2001,21(11):347-1352
提出和验证一种基于偏振-空间编码方案和多重成像技术的光学方法来实现模糊逻辑图像处理,系统中,模糊变量和它们的补被编码为空间正交分布的两个偏振状态。通过对透镜阵列状态的编程,可以实现两个模糊图像间的模糊逻辑操作。本系统中,两个输入图像被偏振编码为8个编码图像作为输入图像,系统是空不变系统,不需要取阈装置和解码过程,通过引进取阈装置,可以在一层系统中实现两个图像间更为复杂的模糊逻辑操作,并给出了实验结果。  相似文献   

11.
A new design approach for a three-step modified signed-digit (MSD) adder is presented that can be optically implemented using binary logic gates. The proposed scheme depends on encoding each MSD digits into a pair of binary digits using a two-state and multi-position encoding scheme. The proposed design algorithm depends on constructing the addition truth table of binary-coded MSD numbers and then using Karnaugh map to achieve output minimization. The optical binary logic gates are obtained by simply programming the decoding masks of a shadow-casting-based optical logic gate system. The proposed scheme results in a simple, compact, and efficient optical binary gate-based parallel addition system.  相似文献   

12.
Self-programmingOpticalLogicProcessorbyusingthePROMDevice¥WANGBinquan;LIULiren;PENGHaifeng;LIANGFeng(InformationOpticsLaborat...  相似文献   

13.
14.
We propose a new spatially encoding method based on simple pattern shift and threshold operations. This new encoding method termed pattern shift encoding (PSE) is suitable for a stacked optical computing system (STOCS). We fabricated a spatial encoder with the PSE consisting of a pattern split processing unit (PU) and a four-input pattern combine PU using the STOCS framework, and successfully implemented the PSE. By combination of this pattern shift encoder and the four nearest neighbors correlator reported previously parallel array logic will be achieved on the STOCS.  相似文献   

15.
Ricardo Arizaga  Roberto Torroba   《Optik》2002,113(8):333-336
We implement a validation technique, based on polarization encoding using the classical digital speckle pattern correlation. A validation mark is generated, which can be magnetically affixed or by means of a chip attached to a primary document. Besides, a decoding key is also generated in the same setup to be sent to the client. In our method, security is twofold by the speckle and polarization characteristics of the procedure. Both encoding and decoding keys are stored digitally. The validation can be achieved by a subtraction operation between both keys performed with conventional software. No additional experimental setups are required in the decoding step. Experimental results are presented to illustrate the method.  相似文献   

16.
Four-operand parallel optical computing using shadow-casting technique   总被引:1,自引:0,他引:1  
Optical shadow-casting (OSC) technique has shown excellent potential for optically implementing two-operand parallel logic gates and array logic operations. The 16 logic functions for two binary patterns (variables) are optically realizable in parallel by properly configuring an array of 2×2 light emitting diodes. In this paper, we propose an enhanced OSC technique for implementing four-operand parallel logic gates. The proposed system is capable of performing 216 logic functions by simply programming the switching mode of an array of 4×4 light emitting diodes in the input plane. This leads to an efficient and compact realization scheme when compared to the conventional two-operand OSC system.  相似文献   

17.
Performances of options for arranging data in the input images of digital optical computing are analyzed and evaluated on the basis of the characteristic functions that the authors formularized. The methods for arranging the data are classified into two options: the spatially expanded bit-pattern arrangement (SEPA) and the bit-slice arrangement (BSA). To analyze and evaluate the performance, the options are applied to the parallel operations based on the optical array logic that is a paradigm of digital parallel computing. Processing steps, storage capacity, and scale of the operation kernel required for performing various parallel operations are analyzed as the characteristic functions. The performances of the SEPA and the BSA are evaluated by comparing these functions. The features of each option are clarified and a guideline for choosing the optimal option is proposed to efficiently perform digital parallel optical operations.  相似文献   

18.
薛康  李勇 《光子学报》2014,39(12):2163-2167
在采用二值时空编码结构照明的三维测量中,由于遮挡、阴影及光学系统的低通滤波特性等原因导致被测物体部分区域解码错误或无法解码.为减轻这些因素对测量结果的影响,提出了一种采用冗余编码的二值时空编码照明三维测量方法.该方法在空间相邻区域设置相同编码,以时间坐标进行区别.解码时,根据编码的冗余性对结果进行校验、残缺编码恢复.与原有编码相比,在不增加投影模式数量的情况下,获得了更多的有效点数,提高了解码的可靠性,并为进一步的纠错提供了更多信息.  相似文献   

19.
三值光学计算机系统结合光强与光的偏振方向表示三值信息,其核心器件——三值逻辑光学处理器是按照降值设计理论完成的,该处理器能完成所有19683种二元三值逻辑运算.本文旨在提出一种实现加法运算的新方法——用三值逻辑光学处理器实现加法.为了解决加法的串行进位延时问题,使用改良符号数表示进行数据编码,从而实现全并行无进位加法.用三值光学计算机与改良符号数表示相结合的方法实现加法既能够充分发挥三值光学计算机位数巨大的优势以及三值逻辑光学处理器能完成所有二元三值逻辑运算的特性,同时又发挥了改良符号数加法的无进位特点.经实验证明该方法具有可行性和正确性,是实现光学加法器的一种新思路.  相似文献   

20.
Optics has already been proved as a successful candidate for conducting parallel logic, arithmetic and algebraic operations. Several all-optical data processors were proposed since last few decades. To implement these systems, different data encoding decoding techniques such as polarization encoding, tristate, quartenary state, multivalued state, symbolic substitution technique etc. have already been proposed. All these are done to use optics in a suitable platform. We propose here a new concept of encoding data by adopting frequencies variation technique for conducting a inversion operation successfully.  相似文献   

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