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  <xsd:element id="lpth_BusinessCombinationRemainingPotentialEarnout" name="BusinessCombinationRemainingPotentialEarnout" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="lpth_CashBenchmarkMember" name="CashBenchmarkMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_ChangeInDeferredIncomeTaxExpenseBenefit" name="ChangeInDeferredIncomeTaxExpenseBenefit" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_ClassACommonStockPerTrancheMember" name="ClassACommonStockPerTrancheMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_ComputerEquipmentAndSoftwareMember" name="ComputerEquipmentAndSoftwareMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_ContingentConsiderationPaymentsClassACommonStockMember" name="ContingentConsiderationPaymentsClassACommonStockMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_DebtInstrumentCovenantMinimumEbitda" name="DebtInstrumentCovenantMinimumEbitda" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_DisposalGroupIncludingDiscontinuedOperationPercentSold" name="DisposalGroupIncludingDiscontinuedOperationPercentSold" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="lpth_DocumentAndEntityInformation" name="DocumentAndEntityInformation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_EarningsPerShareBasicNetOfAccretion" name="EarningsPerShareBasicNetOfAccretion" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_EarningsPerShareDilutedNetOfAccretion" name="EarningsPerShareDilutedNetOfAccretion" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_EarnoutMember" name="EarnoutMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_EarnoutToBePaidInCashMember" name="EarnoutToBePaidInCashMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_EarnoutToBePaidInSharesMember" name="EarnoutToBePaidInSharesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_EngineeringServicesMember" name="EngineeringServicesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_FinanceLeaseCost" name="FinanceLeaseCost" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_G5InfraredMember" name="G5InfraredMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_InfraredComponentsMember" name="InfraredComponentsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_IspOpticsLatviaMember" name="IspOpticsLatviaMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_KnowhowMember" name="KnowhowMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_LatvianStateRevenueServiceMember" name="LatvianStateRevenueServiceMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_LeaseAssets" name="LeaseAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_LeaseLiabilities" name="LeaseLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_LeaseTermsAndDiscountRatesTableTextBlock" name="LeaseTermsAndDiscountRatesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_LesseeOperatingAndFinanceLeaseLiabilityToBePaidMaturity" name="LesseeOperatingAndFinanceLeaseLiabilityToBePaidMaturity" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_LightpathMember" name="LightpathMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_LpoizMember" name="LpoizMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_ManufacturingEquipmentMember" name="ManufacturingEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_NorthRunMember" name="NorthRunMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_NumberOfOperatingLeases" name="NumberOfOperatingLeases" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element id="lpth_OperatingLeaseRightofuseAssetPeriodicIncreaseReduction" name="OperatingLeaseRightofuseAssetPeriodicIncreaseReduction" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_OtherForeignCountriesMember" name="OtherForeignCountriesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_PolicyTable" name="PolicyTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_ProceedsFromPublicOfferingNet" name="ProceedsFromPublicOfferingNet" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="lpth_ProceedsFromSaleOfMachineryAndEquipmentLeaseback" name="ProceedsFromSaleOfMachineryAndEquipmentLeaseback" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_PublicOfferingMember" name="PublicOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_PublicPlacementMember" name="PublicPlacementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_RestrictedStockAwardsAndRestrictedStockUnitsMember" name="RestrictedStockAwardsAndRestrictedStockUnitsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_SICP2002OmnibusPlanMember" name="SICP2002OmnibusPlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_SICP2018OmnibusPlanMember" name="SICP2018OmnibusPlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_SecuritiesPurchaseAgreementMember" name="SecuritiesPurchaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_SellingExpenseMember" name="SellingExpenseMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_SeriesGConvertiblePreferredStockAndWarrantsMember" name="SeriesGConvertiblePreferredStockAndWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_SeriesGConvertiblePreferredStockMember" name="SeriesGConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_SharebasedCompensationArrangementBySharebasedPaymentAwardDiscountFromMarketPrice" name="SharebasedCompensationArrangementBySharebasedPaymentAwardDiscountFromMarketPrice" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="lpth_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestExercisableNumber" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestExercisableNumber" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="lpth_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingNumber" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingNumber" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="lpth_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestOutstandingWeightedAverageRemainingContractualTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_SharebasedCompensationArrangementBySharebasedPaymentAwardForfeitureRate" name="SharebasedCompensationArrangementBySharebasedPaymentAwardForfeitureRate" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_SharebasedCompensationArrangementBySharebasedPaymentAwardMaximumValueOfSharesPerEmployee" name="SharebasedCompensationArrangementBySharebasedPaymentAwardMaximumValueOfSharesPerEmployee" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="lpth_SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedRemainingFiscalYear" name="SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedRemainingFiscalYear" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearFive" name="SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearFive" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearFour" name="SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearFour" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearOne" name="SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearOne" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearThree" name="SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearThree" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearTwo" name="SharebasedPaymentArrangementNonvestedAwardCostNotYetRecognizedYearTwo" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_StockIssuedDuringPeriodSharesNewIssuesAndExistingSharesResold" name="StockIssuedDuringPeriodSharesNewIssuesAndExistingSharesResold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_SupplementalBalanceSheetInformationOnLeasesTableTextBlock" name="SupplementalBalanceSheetInformationOnLeasesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_SupplementalCashFlowInformationOnLeasesTableTextBlock" name="SupplementalCashFlowInformationOnLeasesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_TwentyFourteenEsppMember" name="TwentyFourteenEsppMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_TwentyTwentyEquipmentLoanMember" name="TwentyTwentyEquipmentLoanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_TwentyTwentyThreeEquipmentLoanMember" name="TwentyTwentyThreeEquipmentLoanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_VisibleComponentsMember" name="VisibleComponentsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_VisimidPlanoTxLeaseMember" name="VisimidPlanoTxLeaseMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_VisimidTechnologiesMember" name="VisimidTechnologiesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_WithinSixMonthsMember" name="WithinSixMonthsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_WithinTwelveMonthsMember" name="WithinTwelveMonthsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-income-taxes-income-tax-expense-and-effective-tax-rate-details" name="statement-statement-note-10-income-taxes-income-tax-expense-and-effective-tax-rate-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-income-taxes-tables" name="statement-statement-note-10-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-11-stockbased-compensation-award-activity-details" name="statement-statement-note-11-stockbased-compensation-award-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-11-stockbased-compensation-stockbased-compensation-expense-details" name="statement-statement-note-11-stockbased-compensation-stockbased-compensation-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-11-stockbased-compensation-tables" name="statement-statement-note-11-stockbased-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-11-stockbased-compensation-unrecognized-compensation-cost-details" name="statement-statement-note-11-stockbased-compensation-unrecognized-compensation-cost-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-11-stockbased-compensation-valuation-assumptions-details" name="statement-statement-note-11-stockbased-compensation-valuation-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-12-earnings-loss-per-share-computation-of-earnings-per-share-details" name="statement-statement-note-12-earnings-loss-per-share-computation-of-earnings-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-12-earnings-loss-per-share-securities-excluded-from-earnings-per-share-details" name="statement-statement-note-12-earnings-loss-per-share-securities-excluded-from-earnings-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-12-earnings-loss-per-share-tables" name="statement-statement-note-12-earnings-loss-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-13-leases-lease-expense-details" name="statement-statement-note-13-leases-lease-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-13-leases-lease-term-and-discount-rate-information-details" name="statement-statement-note-13-leases-lease-term-and-discount-rate-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-13-leases-maturities-of-lease-liabilities-details" name="statement-statement-note-13-leases-maturities-of-lease-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-13-leases-supplemental-balance-sheet-information-details" name="statement-statement-note-13-leases-supplemental-balance-sheet-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-13-leases-supplemental-cash-flow-information-details" name="statement-statement-note-13-leases-supplemental-cash-flow-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-13-leases-tables" name="statement-statement-note-13-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-14-loans-payable-future-maturities-of-loans-payable-details" name="statement-statement-note-14-loans-payable-future-maturities-of-loans-payable-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-14-loans-payable-tables" name="statement-statement-note-14-loans-payable-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-15-foreign-operations-longlived-assets-by-country-details" name="statement-statement-note-15-foreign-operations-longlived-assets-by-country-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-15-foreign-operations-revenues-by-country-details" name="statement-statement-note-15-foreign-operations-revenues-by-country-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-15-foreign-operations-tables" name="statement-statement-note-15-foreign-operations-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-16-segment-reporting-reconciliation-of-income-from-segments-details" name="statement-statement-note-16-segment-reporting-reconciliation-of-income-from-segments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-16-segment-reporting-tables" name="statement-statement-note-16-segment-reporting-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisition-of-amorphous-materials-assets-acquired-and-liabilities-assumed-details" name="statement-statement-note-3-acquisition-of-amorphous-materials-assets-acquired-and-liabilities-assumed-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisition-of-amorphous-materials-consideration-transferred-details" name="statement-statement-note-3-acquisition-of-amorphous-materials-consideration-transferred-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisition-of-amorphous-materials-intangible-assets-details" name="statement-statement-note-3-acquisition-of-amorphous-materials-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisition-of-amorphous-materials-pro-forma-information-details" name="statement-statement-note-3-acquisition-of-amorphous-materials-pro-forma-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisition-of-amorphous-materials-tables" name="statement-statement-note-3-acquisition-of-amorphous-materials-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-6-revenue-revenue-by-product-group-details" name="statement-statement-note-6-revenue-revenue-by-product-group-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-6-revenue-tables" name="statement-statement-note-6-revenue-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-7-inventories-inventories-details" name="statement-statement-note-7-inventories-inventories-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-7-inventories-tables" name="statement-statement-note-7-inventories-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-8-property-and-equipment-property-and-equipment-details" name="statement-statement-note-8-property-and-equipment-property-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-8-property-and-equipment-tables" name="statement-statement-note-8-property-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-goodwill-and-intangible-assets-future-amortization-of-intangibles-details" name="statement-statement-note-9-goodwill-and-intangible-assets-future-amortization-of-intangibles-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-goodwill-and-intangible-assets-intangible-assets-details" name="statement-statement-note-9-goodwill-and-intangible-assets-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-goodwill-and-intangible-assets-tables" name="statement-statement-note-9-goodwill-and-intangible-assets-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
