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  <xsd:element abstract="true" id="luna_SeventhLoanModificationAgreementMember" name="SeventhLoanModificationAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedInPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedInPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsConvertedWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAggregateIntrinsicValueRepurchased" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedAggregateIntrinsicValueRepurchased" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsRepurchasesInPeriod" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsRepurchasesInPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsRepurchasesInPeriodWeightedAverageGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsRepurchasesInPeriodWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsVested" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsVested" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerLimit" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeLowerLimit" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element abstract="true" id="luna_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeRollForward" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeRollForward" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperLimit" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeUpperLimit" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="instant" />
  <xsd:element id="luna_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisedInPeriodExercisePriceRangeUpperRangeLimit" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisedInPeriodExercisePriceRangeUpperRangeLimit" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansForfeituresInPeriodExercisePriceRangeLowerRangeLimit" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansForfeituresInPeriodExercisePriceRangeLowerRangeLimit" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansForfeituresInPeriodExercisePriceRangeUpperRangeLimit" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansForfeituresInPeriodExercisePriceRangeUpperRangeLimit" nillable="true" substitutionGroup="xbrli:item" type="num:perShareItemType" xbrli:periodType="duration" />
  <xsd:element id="luna_SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsNonvestedAggregateIntrinsicValueGranted" name="SharebasedCompensationArrangementbySharebasedPaymentAwardEquityInstrumentsOtherthanOptionsNonvestedAggregateIntrinsicValueGranted" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration" />
  <xsd:element id="luna_SignificantPurchaseCommitmentTimePeriod" name="SignificantPurchaseCommitmentTimePeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="luna_SiliconValleyBankMember" name="SiliconValleyBankMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="luna_SixthLoanModificationAgreementMember" name="SixthLoanModificationAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="luna_TechnologyDevelopmentMember" name="TechnologyDevelopmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="luna_TunableLasersMember" name="TunableLasersMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="luna_UnitedStatesGovernmentMember" name="UnitedStatesGovernmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>