<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2013-10-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000099106</issuerCik>
        <issuerName>TRANS LUX CORP</issuerName>
        <issuerTradingSymbol>TNLX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001089801</rptOwnerCik>
            <rptOwnerName>SCHIELE GEORGE W</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>19 HILL ROAD</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GREENWICH</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06830</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Warrant</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0.5</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2013-10-02</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>500000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2014-10-02</value>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2018-10-02</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>500000</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>500000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">500,000 Warrants were granted to Mr. Schiele by the Board of Directors and approved by the stockholders at the 2013 Annual Meeting. 165,000 are exercisable after 1 year; an additional 165,000 warrants are exercisable after 2 years; and all of the warrants are exercisable after 3 years.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ George W. Schiele</signatureName>
        <signatureDate>2013-10-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
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X0306
4
2013-10-02
0
0000099106
TRANS LUX CORP
TNLX
0001089801
SCHIELE GEORGE W
19 HILL ROAD
GREENWICH
CT
06830
1
0
0
0
Warrant
0.5
2013-10-02
4
A
0
500000
0
A
2014-10-02
2018-10-02
Common Stock
500000
500000
D
500,000 Warrants were granted to Mr. Schiele by the Board of Directors and approved by the stockholders at the 2013 Annual Meeting. 165,000 are exercisable after 1 year; an additional 165,000 warrants are exercisable after 2 years; and all of the warrants are exercisable after 3 years.
/s/ George W. Schiele
2013-10-17