Control method for the optical components of a dynamically reconfigurable optical platform

Control method for the optical components ofa dynamically reconfigurable optical platform

Xianchao Wang,1,2 Junjie Peng,1,* and Shan Ouyang1

1School of Computer Engineering and Science, Shanghai University,149 Yanchang Road, Shanghai 200072, China

2School of Mathematics and Computational Science, Fuyang Normal College,741 East Qinghe Road, Fuyang 236041, China

*Corresponding author: [email protected]

Received 25 August 2010; revised 12 November 2010; accepted 3 December 2010;posted 22 December 2010 (Doc. ID 133799); published 4 February 2011

We propose a control method for the optical components of a dynamically reconfigurable optical platform,the ternary optical computer (TOC). The optical components are made of liquid-crystal cell arrays(LCCAs) and polarizers, so the control method is for generating the pilot signals of the LCCAs to meetuser demands. In this work, we first briefly introduce the TOC theory, the modules in the TOC monitorsystem, and the addressing of these LCCAs. Then we focus on the method for generating the controlinformation (CI) of optical components, i.e., the encoder and the operator in the TOC according tothe operands and the information about the basic operating units needed by an operation. In addition,we define data structures, some of which store the information to generate the CI and others that mainlystore the generated CI. Finally we provide an example to verify the proposed method and conduct anexperiment to generate the LCCA CI. The results demonstrate the correctness and feasibility of themethod. © 2011 Optical Society of AmericaOCIS codes: 160.3710, 200.3760, 200.4740, 200.4960, 230.3720, 230.5440.

1. Introduction

The liquid-crystal cell array (LCCA) has many desir-able characteristics, such as high optical efficiency,parallel processing, and wide availability. And theliquid-crystal cell (LCC) can change the polarizationdirection of light when a pilot signal voltage isapplied on it [1]. Therefore, the LCCA can offer anexciting medium for diffractive optical elements[2,3], optical correlators [4], two-dimensional spatiallight modulators [5–7], interferometers [8,9], polari-zation diffraction gratings [10–12], optical logic gates[1,13,14], optical pattern recognition [4], and opticalimage processing [15]. In addition, there are also newapplications where the LCCA can be used to controlthe two-dimensional polarization states of the outputbeam. For example, Jin et al. proposed an optical

computer principle and architecture [16] in whichthey used LCCAs to control the polarization of light.

In optical computing, Jin et al. used three stablelight states, no-intensity light (NIL), horizontally po-larized light (HPL), and vertically polarized light(VPL), to represent information. And in order to im-plement encoding and operating, he utilized someLCCAs to control the polarization of light and polar-izers to filter beams. Some considerable develop-ments have been obtained on the ternary opticalcomputer (TOC) in the last several years. For exam-ple, in 2008, the decrease-radix design principle(DRDP) was proposed [17], and a TOC experimentplatform was built according to the principle. Re-cently, the optical vector-matrix multiplication [18]and a cellular automata calculation model [19] wereperformed on the experiment platform. One can seethat the TOC is a digital, dynamically reconfigur-able, and multiple-instruction multiple-data (MIMD)system from [18,19]. However, parallel operation

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could not be achieved on the experiment platformbecause the control modes of those LCCAs were se-quential scanning. In order to achieve the parallel op-eration, we designed a new LCCA in which each pixelwas controlled by a pin and we built another new ex-periment platform with the new LCCA in 2009.

According to the DRDP, any two-input ternary lo-gic operation can be implemented on the TOC experi-ment platform. However, the work relies on all theLCCA control information (CI) generated by theTOC monitor system. But the software to generate ithas not yet been exploited. Therefore, to implementany two-input ternary logic operation, the CImust begenerated according to the truth table and the oper-ands of a certain operation.

The rest of the article is organized as follows.Section 2 briefly describes the TOC and the DRDP.Section 3 focuses on the method for generating theCI of these LCCAs on the new experiment platform.Section 4 mainly illustrates the correctness and fea-sibility of the proposed method on the TOC throughan experiment. And the last section gives the con-cluding remarks and the consideration of futurework.

2. Related Work

A. Brief Introduction to the Ternary Optical Computer

Figure 1 illustrates the optical components of theTOC. There are seven polarizers altogether (VP1,VP2, VP3, VP4, VP5, HP1, and HP2), three layersof monochromatic LCCAs (L1, L2, and L3), and onephotoreceptor array (D) in the optical components.The polarizers include two kinds: vertical (VPi,i ¼ 1, 2, 3, 4, 5) and horizontal (HPi, i ¼ 1, 2). TheVPi is clear to the VPL, and the HPi is clear tothe HPL; all other cases are opaque. In Fig. 1, S isthe light source; E is the encoder, which containsVP1, L1, VP2, and L2. It converts the binary electricsignals into ternary optical ones (please refer toSubsection 3.D for a more detailed discussion); Ois the reconfigurable trivalued logic optical processor,

which contains VP3, HP1, L3, VP4, HP2, and VP5—it is equally divided into four parts, VV, VH, HH, andHV, respectively (it is mainly used to accomplish op-tical computing, i.e., changing the light states); and Dis the photoreceptor array, which reconverts the tern-ary optical signals into the binary electric ones. Here,two layers of LCCAs of the encoder E need their CI togenerate VPL, HPL, or NIL. At the same time, thethird layer of the LCCAs of the operator O also needsits CI to complete optical computing. In this paper,we will mainly investigate the CI generation ofall the LCCAs, to be discussed in detail in Subsec-tions 3.D–3.F.

B. Decrease-Radix Design Principle

The DRDP was put forward by Yan et al. [17]. Accord-ing to the DRDP, any of the nn2 two-input n-valuedlogic operations can be implemented by combinationof some basic operating units (BOUs). To the n-valued logic, there are n2ðn − 1Þ different BOUs.The process to implement an operation by composingsome BOUs is called reconfiguration [17].

If n ¼ 3, it can be easily found that there are alto-gether 19,683 kinds of two-input trivalued logic op-erations and 18 kinds of BOUs. In the case of theTOC, any one-bit two-input trivalued logic processorcan be dynamically reconfigured at runtime by nomore than six BOUs. All the BOUs have the sameconfiguration: an LCC is sandwiched by two polari-zers. By aggregating all the BOUs with the same po-larizers, we can set up the optical operator of theTOC. As mentioned above, the optical operator of theTOC consists of four parts, i.e., VV, VH, HH, and HV.On the new platform, each part is made up of anLCCA, with 24 × 24 LCCs, i.e., 576 BOUs, sand-wiched by two polarizers. According to the propertyof polarizers, the operation results are VPL or NIL inVV and HV, and HPL or NIL in VH and HH.

According to the configuration of BOUs and theparts where they are located, all of these BOUscan be classified into 50 kinds, shown in Table 3.For convenience, the BOU with No. p is written as

Fig. 1. Architecture of the TOC.

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BOUp, the BOUs with Nos. from p to q as BOUp–q,and the BOUs with No. p and q as BOUp;q. In Table 3,BOU1–18 are the most fundamental BOUs. Function-ally, each of BOU21–44 and BOU51–58 is merged by twoand three of BOU1–16, respectively. For example,BOU21 is merged by BOU1 and BOU3, and BOU51by BOU1, BOU3, and BOU5. Thus, any one-bit two-input trivalued logic processor can be dynamicallyreconfigured by no more than six BOUs, and no morethan three BOUs are needed in each part.

Based on the DRDP, two TOC experiment plat-forms had been built in Shanghai University by theend of 2009. Each of them is a dynamically reconfigur-able optical computer. In this paper, we will discussthe CI generation of L3 in the new optical platform,according to the DRDP. For a detailed discussionabout this issue, please refer to Subsection 3.F.

3. LCCA Control Information Generation in theTernary Optical Computer

A. LCCA Addressing

To control the LCCAs in the TOC, we address themfirst. As mentioned in Subsection 2.B, the encoderneed not be divided into four parts, as does the opera-tor. But it is divided into four parts for the conveni-ence of control. Thus there are, altogether, 12 LCCAsin the optical components of the TOC. There are 24 ×24 LCCs in each LCCA, and these LCCAs will be ad-dressed individually. Each pixel is addressed with arow number and column number, each from 0 to 23.The schematic diagram is shown in Fig. 2, and eachsmall square indicates an LCC.

B. Relevant Data Structures

To generate the LCCACI, some data structures mustbedefined.TheyareTASK,USERINFO,OPERATIO-NINFO, OPRND, and OPERATORINFO, shown inFig. 3, where the left data structures are used tostore the information, which is employed to generatethe LCCA CI, and the right data structures areused to store the CI. Their functions are as follows,respectively:

• TASK is used to store an operation request, i.e.,a task. The structure consists of four fields: User,Operation, Oprnd, and lpNext. The field User is aUSERINFO structure, and Operation, Oprnd, andlpNext store the pointers to OPERATIONINFO,OPRND, and next task, respectively. All the tasksform a queue. The head node of the task queue is gen-erated while the system starts. The modules in themonitor system can obtain the useful informationfrom the pointer to the head node to generate theLCCA CI.

• USERINFO stores user information. User-Name, RequestTime, TaskNum, and Socket inUSERINFO are, respectively, the name, requesttime, task number, and socket of a certain user,where TaskNum is used to differentiate tasks ofthe same user and Socket is used to return the opera-tion results to the user.

• OPERATIONINFO consists of ONumber,OperatorID, MfL2P, and lpNext. Maybe there aremultiple operations and multiple operands in a taskbecause the TOC is aMIMD system. Therefore, thereis a field ONumber to store the number of operandsin a certain operation and a field lpNext to point tothe next operation. OperatorID represents the ID ofthe logic operation and points to a OPERATORINFOnode. MfL2P points to a MFL2P node.

• OPRND consists of OperandA, OperandB,BitNumber, and lpNext. Where OperandA and

Fig. 2. Schematic diagram of each LCCA address.

Fig. 3. Data structures used to generate the CI.


OperandB store the A-port and B-port operands ofthe logic operation pointed by OperatorID, respec-tively. BitNumber represents the bits of the operand,and lpNext points to the next operand.

• OPERATORINFO consists of IDNum,TrthTab, UnitNum, BOUNum[6], and NumArea[4].As mentioned above, there are 19,683 kinds of two-input trivalued logic operations. To achieve an opera-tion, its logic truth table must be mapped into aphysical one represented by three optical states [17],i.e., VPL, HPL, and NIL. Therefore, there is a fieldIDNum to distinguish operations and to store theID of a physical truth table. TrthTab stores the phys-ical truth table to achieve one operation. UnitNumstores the number of the BOUs needed by such aone-bit operation. The array BOUNum[6] storesthe serial numbers of these BOUs. And the array Nu-mArea[4] stores the numbers of these BOUs locatedin VV, VH, HH, and HV, respectively. The informa-tion about all OPERATORINFO nodes is read intothe memory to be used while the monitor systemstarts.

• MFL2P stores the map from the input symbolsof a certain operation to these three optical states.

• LCCACTRLINFO stores all of the LCCA CI.Where LCI1, LCI2, and LCI3 all point to a FOURAR-EA node, the array Number[4] stores the numbers ofBOUs in different parts when once-through opera-tion is achieved. Here, once-through operationmaybe includes several operations because the opti-cal platform is a MIMD system.

• FOURAREA points to the CI of a layer ofLCCAs. Where VV, VH, HH, and HV in the structureall point to a MULTIBYTES node.

• MULTIBYTES stores the CI of an LCCA. Andit is a array with 24 rows and 3 columns. In theMULTIBYTES node, there are 3 bytes in each row,

i.e., FirstB, SeconB, and ThirdB. And each bytestores the CI of eight LCCs in the same row as anLCCA.

• LCCAADDRESS indicates the start address ofan LCCA when its CI is generated. In the structure,Row and Col indicate the row and column of the startaddress. For details of the LCCA addressing, pleaserefer to Subsection 3.A. The system has the firstchoice of row to generate the CI. In other words, toachieve a certain operation, the LCCs in the secondrow will be used after those in the first row run out,and so forth. Obviously, each LCCA need anLCCAADDRESS to point to its start address.

In Subsections 3.D–3.F, we will discuss how to gener-ate the CI according to the information stored in theTASK node, and the generated CI will be stored inthe LCCACTRLINFO node.

C. Monitor System in the Ternary Optical Computer

LCCA CI is achieved by the CI generation module(CIGM), which is an important component of themonitor system in the TOC. All the modules andtheir relationships are shown in Fig. 4, where the cli-ent, first of all checks the truth tables and the oper-ands input by user and then submits the operationrequest to the server. The operation request containsthe name of the user and an operation queue, i.e.,several truth tables and their operands. Finally, itwaits for the operation results sent by the server anddisplays them. In Fig. 4, the broken lines indicate thedata stream, the thin lines represent the control sig-nals sent from the control module (CM), and the boldlines represent the control signals sent to the CM.Meanwhile, we can see that the monitor systemmainly consists of the CM, the network communica-tion module (NCM), the data preprocess module

Fig. 4. Monitor system in the TOC.


(DPPM), the CIGM, the local communication module(LCM), the encoder, the operator, the photoreceptorarray and the decode module (DM). Their functionsare as follows:

• The CM receives the feedback signals fromother modules, and then decides the next operations,according to the signals, to achieve the informationdissemination among the modules.

• The NCM is responsible for the communicationbetween the client and the server. On the one hand,after receiving all data, it generates a TASK node,fills up the fields RequestTime and Socket inUSERINFO, and sends the reception-finished signal(RFS) to the CM. And the CM sends the data prepro-cess signal (DPPS) to the DPPM after receivingthe RFS from the NCM. On the other hand, theNCM sends the operation results received from theDM to the client after receiving the operation-finished signal from the CM and deletes the TASKnode.

• The DPPM processes the data received by theNCM after receiving the DPPS. The processing ofdata includes splitting the truth table, the operandsand the name of user, filling up the fields UserNameand TaskNum in USERINFO, and generating theOPERATIONINFO queue and the OPRND queue fora task. And then it sends the process-finished signal(PFS) to the CM. The CM sends the generate-control-information signal (GCIS) to the CIGM afterreceiving the PFS.

• The CIGM mainly generates the CI of threelayers of LCCAs in each parts according to theOPERATIONINFO queue and OPRND queue ofthe first TASK node after receiving the GCIS fromthe CM. It will generate the CI for the next TASKnode if there are enough BOUs in each parts to use.Otherwise, it will send all the CI in an LCCACTR-LINFO node to the LCM.

• The LCM is responsible for the communicationbetween the optical components and the DM, theCIGM. On the one hand, on receiving the CI of allthe LCCAs from the CIGM, the LCM sends it tothe corresponding LCCAs. On the other hand, on re-

ceiving the data from the photoreceptor array, theLCM sends them to the DM.

• The encoder and the operator are made up ofthe LCCAs and some polarizers, as mentioned above.The encoder generates VPL, HPL, and NIL as soonas it receives its own CI, and the operator imple-ments optical computing immediately when receiv-ing its own CI.

• The photoreceptor array is in charge of gather-ing the output of the operator not by measuring theintensities but by judging whether the BOU is brightor not. At the same time, it transforms the ternaryoptical information into a binary electric one. Aftergathering the data, it send them to the LCM.

• The DM decodes the results gathered by thephotoreceptor array. After decoding, it sends a signalto the CM. The CM, according to the signal, judgeswhether the decoded results take part in another op-eration or not. The decoded results are sent to theCIGM if they are the operands of another operation;otherwise, they are sent to the NCM.

As mentioned above, all of these modules achieveoptical computing in harmony with each other.

D. Control Information of the Encoder

The state of an LCC is defined by the voltage appliedto it, and the state determines whether the LCC ro-tates the incident polarized light or not. On the newoptical platform, polarized light entering a nonener-gized LCC is twisted by 90° on exit and an electricfield applied across the LCC causes the polarizedlight to go through without being twisted. This prop-erty of the LCC can be used to form the encoder andthe operator of the TOC. The encoding is shown inFig. 5, where LCC1 and LCC2 are two LCCs, VP1and VP2 are two vertical polarizers, E ¼ 0 meansthat the LCC is nonenergized, and E ¼ 1 means thatit is energized. From Fig. 5, we find that the encodercan generate three optical states, i.e., VPL, HPL, andNIL, by controlling LCC1 and LCC2. According toFig. 5, we can obtain their CI, shown in Table 1, tooutput three such optical states.

Fig. 5. Encoding of the TOC.


In Table 1, the symbol “0” means E ¼ 0 and “1”means E ¼ 1. We see that there are two groups ofCI that can make the encoder generate NIL. In thiswork, we select CE0 to make the encoder output NIL.

E. Control Information of the Operator

In this work, we have not realized light control on thereconfigurable optical platform. Therefore, we nowuse the electric signals to control each LCC to changethe polarization of light. For the three kinds of con-trol light, there are eight control logics (shown inTable 2) to control the 50 BOUs, i.e., the LCCs ofthe third layer of the LCCAs. In Table 2, the symbol“0” also means E ¼ 0 and “1” also means E ¼ 1.

The control of any BOU is one of the eight controllogics. For example, the BOU10 is controlled withCO5 when it is used to achieve a certain operation.If the control light is NIL or HPL, its electric controlsignal is “1,” otherwise “0.”

To generate the CI of operator L3, we, first of all,determine the control logic of each kind of BOU,shown in Table 3. Theoretically, the BOU17 andBOU18 can transformNIL into VPL or HPL, and theyare implemented functionally by use of the otherBOUs. In this work, we do not discuss it. Conse-quently, their control logics are not shown in Table 3.“Swap” in Table 3 refers to whether or not the oper-ands of the A-port and B-port are exchanged to gen-erate the CI of a BOU when it is used by a certainoperation. Symbol “N” indicates that they are not ex-changed, and “Y” indicates that they are exchanged.For instance, the BOU5;8;9;13;27 are used to implementa certain operation. In Table 3, we can see that theoperands of two ports are exchanged to generate theCI of BOU5;8;27, and they are not exchanged to gen-erate the CI of BOU9;13.

F. LCCA Control Information Generation

The CIGM will, according to the OPERATIONINFOqueue and the OPRND queue in the first TASK node(Tables 1 and 3), generate the CI of all BOUs neededby the task after it receives the GCIS from the CM.

We assume that the number nð1 ≤ n ≤ 6Þ of the BOUsneeded by a certain operation has been obtained froma OPERATORINFO. The steps to generate the CI ofthe BOUs for such a one-bit operation are as follows:

Step 1: Judge whether there are enough BOUs ineach part to achieve the operation or not, accordingto the contents of LCCAADDRESS. Jump to Step 2directly if there are enoughBOUs in each part. Other-wise, Jump to Step 2 after sending the generatedCI tothe LCM and generating a new LCCACTRLINFOnode.

Step 2: Get the serial number of a BOU from theOPERATORINFO.

Step 3: Judge whether the operands of A-port andB-port need swapping or not according to the serialnumber. Jump to Step 4 if they do not need swapping.Otherwise, jump to Step 4 after they are swapped.

Step 4: Generate the CI of the encoder, i.e., L1 andL2, according to Table 1 and the mapped optical stateof the B-port operand.

Step 5: Store the generated CI into the both corre-sponding positions, which are pointed to by bothstart addresses, in the LCCACTRLINFO node.And then increase each address by 1.

Step 6: Generate the CI of the BOU, according toTable 3 and the mapped optical state of the A-portoperand.

Step 7: Store the generated CI into the correspond-ing position, which is also pointed by a start address,in the LCCACTRLINFO node. And then increase theaddress by 1.

Step 8: Decrease n by 1. Judge whether n is equalto 0 or not. Jump to Step 9 if n is equal to 0. Other-wise, jump to Step 3.

Step 9: Complete the CI generation for this one-bitoperation.

To generate all the CI of the BOUs needed by the op-eration, the steps mentioned above will be repeated.

4. Example and Experiment

We have discussed how to generate the LCCA CI.Now we give an example to show the process. Firstof all, the system should initialize the LCCA CI be-fore it generates the CI for an operation. Obviously,the output of the encoder is initialized NIL. In otherwords, all CI of L1 and L2 is initialized with “0.” Andthe CI of all BOUs is also initialized with “0.” We as-sume that the truth table of an operation called Ttransformation is shown in Table 4 and the operandsof A and B ports are 111uuu000 and 1u01u01u0,

Table 1. Control Information of the Encoder

Control

OutputNo. LCC1 LCC2

CE0 0 0 NILCE1 0 1 NILCE2 1 0 HPLCE3 1 1 VPL

Table 2. Eight Electric Control Logics for Three Optical States

Control Light

No.

CO0 CO1 CO2 CO3 CO4 CO5 CO6 CO7

NIL 0 0 0 0 1 1 1 1VPL 0 0 1 1 0 0 1 1HPL 0 1 0 1 0 1 0 1


respectively. And we call the leftmost bit in theoperands the first one.

On the basis of the DRDP, the map from the inputsymbols to the three optical states is shown inTable 5. And the L1 and L2 CI for different opticalstates are also shown in Table 5.

The BOUs needed by the one-bit T transformationand their CI are shown in Table 6. We can see thatthe one-bit T transformation needs 5 BOUs, andthere are 1, 1, 1, and 2 BOU(s) in VV, VH, HH,and HV, respectively.

We can obtain the CI to achieve the operation ac-cording to the operands (Tables 5 and 6). Let us takethe second-bit operands, i.e., “1” and “u,” for instance,to demonstrate the process of generating the CI. Theoperands “1” and “u” are, respectively, mapped intothe HPL and NIL, according to Table 5. For eachBOU, its CI generation is as follows:

• For BOU5, the LCC CI in L1 and L2 is gener-ated with HPL and the one in L3 is generated with

NIL because the operands need swapping. Accordingto Table 5, the LCC CI in L1 and L2 is, respectively,“1” and “0” to generate HPL. And the LCC CI in L3 is“0” according to Table 6. Meanwhile, the BOU5 is lo-cated in HV. Therefore, the LCC CI of L1, L2, and L3in HV is “1,” “0” and “0,” respectively.

• For BOU8, similar to BOU5, the LCC CI of L1,L2, and L3 in VH is “1,” “0,” and “1,” respectively.

• For BOU9, the LCC CI in L1 and L2 is gener-ated with NIL and the one in L3 is generated withHPL because the operands do not need swappingand it belongs to VV. We can obtain the LCC CI,i.e., “0,” “0,” and “0,” of L1, L2, and L3 in VV,respectively.

• For BOU13, similarly to BOU9, the LCC CI ofL1, L2, and L3 in HV is “0,” “0,” and “1,” respectively.

• For BOU27, similarly to BOU5, the LCC CI ofL1, L2, and L3 in HH is “1,” “0,” and “0,” respectively.

The start address of the part which an LCC belongsto is increased by 1 to store next LCCCI after its CI isstored. All the CI to implement this 9 bit T transfor-mation is shown in Table 7. The bold font represents

Table 3. Basic Operating Unit Information to Generate the Control Information of L3

No. Part Control Logic No. Swap No. Part Control Logic No. Swap

1 HV CO6 N 28 HH CO6 Y2 HH CO1 N 29 HH CO5 Y3 VV CO1 N 30 HH CO3 N4 VH CO2 N 31 HH CO6 N5 HV CO3 Y 32 HH CO5 N6 HH CO4 Y 33 VH CO4 Y7 VV CO5 Y 34 VH CO1 Y8 VH CO6 Y 35 VH CO2 Y9 VV CO2 N 36 VH CO4 N

10 VH CO5 N 37 VH CO1 N11 VV CO4 Y 38 VH CO2 N12 VH CO3 N 39 VV CO3 Y13 HV CO3 N 40 VV CO6 Y14 HH CO4 N 41 VV CO5 Y15 VV CO4 N 42 VV CO3 N16 VH CO3 N 43 VV CO6 N17 VV — — 44 VV CO5 N18 HH — — 51 HV CO0 N21 HV CO4 Y 52 HH CO7 N22 HV CO1 Y 53 HV CO0 N23 HV CO2 Y 54 HH CO7 N24 HV CO4 N 55 VV CO7 N25 HV CO1 N 56 VH CO0 N26 HV CO2 N 57 VV CO7 N27 HH CO3 Y 58 VH CO0 N

Table 4. Truth Table of T Transformation

a b Result

u u u0 0 01 1 1u 0 u0 1 11 u 0u 1 00 u u1 0 1

Table 5. Map from the Input Symbols to Optical States and the Controlof the Encoder

Map from the Input Symbolsto Three Optical States Control of the Encoder

Input Symbol Optical State L1 L2 No.

u NIL 0 0 CE00 VPL 1 1 CE31 HPL 1 0 CE1


the LCC CI to implement the second-bit T transfor-mation. And the outputs of all BOUs needed by this9 bit T transformation are also shown in the last rowin Table 7, according to these CI. In the last row, “1”

indicates that the BOU is bright and “0” indicates itis dark.

According to the method described above, we pro-grammed the software to generate LCCA CI for anytwo-input trivalued logic operation. The CI, gener-ated by the software, of the 9 bit T transformationis shown in Fig. 6. In the figure, 9, 9, 9, and 18are the numbers of BOUs that will be used in VV,VH, HH, and HV, respectively.

After the CI is sent to the optical components, wecan obtain its outputs, shown in Fig. 7. Theoretically,the operation results can be obtained by judgingwhether the BOUs are bright or not, but in fact thereare several different intensity levels in each part be-cause of the limitation of experiment condition. For

Table 6. Basic Operating Units Needed by T Transformation andTheir Information

No. Part Swap

CI

NIL VPL HPL No.

5 HV Y 0 1 1 CO38 VH Y 1 1 0 CO69 VV N 0 1 0 CO2

13 HV N 0 1 1 CO327 HH Y 0 1 1 CO3

Table 7. Control Information to Achieve the Operation in the Example and Their Outputs

VV VH HH HV

L1 101101101 111000111 111000111 111011010001111011L2 001001001 000000111 000000111 000001000001101011L3 000000111 011011011 101101101 110111100010110111

Output 000000001 000000100 101000000 001000010000000000

Fig. 6. CI to achieve the operation in the example.

Fig. 7. (Color online) Outputs of achieving the operation in the example.


the same reason, BOUs may have several intensitylevels and only those greater than a given intensitylevel threshold are served as bright BOUs. FromFig. 7, we can obtain the decoded results of VV, VH,HH, and HV. They are 000000001, 000000100,101000000, and 001000010000000000, respectively.They are identical with the last row in Table 7.Therefore, the experiment has proved the correct-ness of the proposed method for generating theLCCA CI.

5. Conclusions

From the discussion above, we can see that the pro-cess of generating the LCCA CI is one of allocatingthe LCCs to complete operations for users. The ex-periment has demonstrated that the proposed meth-od for generating the LCCACI is correct and feasible.It can be seen, from the process of generating LCCACI, that the method does not fragment the LCCAs asmemory allocation. This can improve the efficiency ofthe pixels. At the same time, the system uses onebyte to control eight pixels, which can decrease thecommunication from the monitor computer to the op-tical components of the TOC. Thus, the overall per-formance will be improved.

Though this study has succeeded in generating theCI of all the LCCAs in the TOC, we are far from im-plementing the monitor system of the TOC. We willfocus on how to decode and how to obtain the opera-tion results from the decoded results.

This work was supported by the National NaturalScience Foundation of China (NSFC) (61073049), thePh.D. Programs Foundation of the Ministry ofEducation of China (20093108110016), the ShanghaiLeading Academic Discipline Project (J50103), theResearch Project of Excellent Young Talents in theUniversities in Shanghai (B.37-0108-08-002), andthe Natural Science Research Project of Higher Edu-cation in Anhui (KJ2010B150). The authors thank YiJin for providing the optical platform and givingsome good advice on the paper. And the authors alsowould like to thank the reviewers for their helpfulcomments, remarks, and suggestions, which led toimprovements of the paper.

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Control method for the optical components of a dynamically reconfigurable optical platform