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  <xsd:element abstract="true" id="lpth_LightpathPlanMember" name="LightpathPlanMember" 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_LyttonBuyersMember" name="LyttonBuyersMember" 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 id="lpth_NetAssetsAcquiredMeasurementPeriodAdjustment" name="NetAssetsAcquiredMeasurementPeriodAdjustment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_NewHampshireTaxAuthorityMember" name="NewHampshireTaxAuthorityMember" 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_NumberOfCustomers" name="NumberOfCustomers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <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 id="lpth_OperatingLossCarryforwardLimitationOnTaxableIncomePercent" name="OperatingLossCarryforwardLimitationOnTaxableIncomePercent" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="lpth_OperatingLossCarryforwardsNotSubjectToExpiration" name="OperatingLossCarryforwardsNotSubjectToExpiration" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="lpth_OperatingLossCarryforwardsSubjectToExpiration" name="OperatingLossCarryforwardsSubjectToExpiration" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="lpth_OrlandoFlLeaseMember" name="OrlandoFlLeaseMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" 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_OtherStateTaxAuthoritiesMember" name="OtherStateTaxAuthoritiesMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_PaymentTaxWithholding" name="PaymentTaxWithholding" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="lpth_PaymentTaxWithholdingDividends" name="PaymentTaxWithholdingDividends" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="lpth_PaymentsToAcquireBusinessesNetOfAdjustmentsAndClawback" name="PaymentsToAcquireBusinessesNetOfAdjustmentsAndClawback" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" 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 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_RateAfter2MillionMember" name="RateAfter2MillionMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_RateAfterFullPaymentMember" name="RateAfterFullPaymentMember" 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 id="lpth_RetainedEarningsAvailableForRepatriation" name="RetainedEarningsAvailableForRepatriation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="lpth_SICP2018OmnibusPlanMember" name="SICP2018OmnibusPlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_ScheduleOfIncomeTaxesPaidTableTextBlock" name="ScheduleOfIncomeTaxesPaidTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" 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 abstract="true" id="lpth_SeriesGPurchasersMember" name="SeriesGPurchasersMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_SeriesGPurchasersWarrantsMember" name="SeriesGPurchasersWarrantsMember" 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_SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOutstandingWeightedAverageRemainingContractualTerm" name="SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsNonvestedOutstandingWeightedAverageRemainingContractualTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <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_StockIssuedDuringPeriodSharesExerciseOfWarrants" name="StockIssuedDuringPeriodSharesExerciseOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_StockIssuedDuringPeriodSharesExistingSharesResold" name="StockIssuedDuringPeriodSharesExistingSharesResold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_StockIssuedDuringPeriodSharesNewIssuesAndExistingSharesResold" name="StockIssuedDuringPeriodSharesNewIssuesAndExistingSharesResold" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_StockIssuedDuringPeriodValueExerciseOfWarrants" name="StockIssuedDuringPeriodValueExerciseOfWarrants" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" 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_ThreeCustomersMember" name="ThreeCustomersMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" 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_TwentyTwentyFiveEsppMember" name="TwentyTwentyFiveEsppMember" 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 id="lpth_VatPolicyPolicyTextBlock" name="VatPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_VatRate" name="VatRate" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="lpth_VatReceivablesPayables" name="VatReceivablesPayables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" 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_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-compensatory-equity-incentive-plan-and-other-equity-incentives-award-activity-details" name="statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-award-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-intrinsic-and-fair-values-of-awards-details" name="statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-intrinsic-and-fair-values-of-awards-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-stockbased-compensation-expense-details" name="statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-stockbased-compensation-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-summary-of-plans-details" name="statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-summary-of-plans-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-tables" name="statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-unrecognized-compensation-cost-details" name="statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-unrecognized-compensation-cost-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-valuation-assumptions-details" name="statement-statement-note-10-compensatory-equity-incentive-plan-and-other-equity-incentives-valuation-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-11-earnings-loss-per-share-computation-of-earnings-per-share-details" name="statement-statement-note-11-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-11-earnings-loss-per-share-securities-excluded-from-earnings-per-share-details" name="statement-statement-note-11-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-11-earnings-loss-per-share-tables" name="statement-statement-note-11-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-16-foreign-operations-longlived-assets-by-country-details" name="statement-statement-note-16-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-16-foreign-operations-revenues-by-country-details" name="statement-statement-note-16-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-16-foreign-operations-tables" name="statement-statement-note-16-foreign-operations-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-17-segment-reporting-reconciliation-of-income-from-segments-details" name="statement-statement-note-17-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-17-segment-reporting-tables" name="statement-statement-note-17-segment-reporting-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisitions-assets-acquired-and-liabilities-assumed-details" name="statement-statement-note-3-acquisitions-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-acquisitions-consideration-transferred-details" name="statement-statement-note-3-acquisitions-consideration-transferred-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisitions-intangible-assets-details" name="statement-statement-note-3-acquisitions-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-3-acquisitions-pro-forma-information-details" name="statement-statement-note-3-acquisitions-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-acquisitions-tables" name="statement-statement-note-3-acquisitions-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-4-revenue-revenue-by-product-group-details" name="statement-statement-note-4-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-4-revenue-tables" name="statement-statement-note-4-revenue-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-5-inventories-net-inventories-details" name="statement-statement-note-5-inventories-net-inventories-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-5-inventories-net-tables" name="statement-statement-note-5-inventories-net-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-6-property-and-equipment-net-property-and-equipment-details" name="statement-statement-note-6-property-and-equipment-net-property-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-6-property-and-equipment-net-tables" name="statement-statement-note-6-property-and-equipment-net-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-7-goodwill-and-intangible-assets-future-amortization-of-intangibles-details" name="statement-statement-note-7-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-7-goodwill-and-intangible-assets-goodwill-details" name="statement-statement-note-7-goodwill-and-intangible-assets-goodwill-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-7-goodwill-and-intangible-assets-intangible-assets-details" name="statement-statement-note-7-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-7-goodwill-and-intangible-assets-tables" name="statement-statement-note-7-goodwill-and-intangible-assets-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-income-taxes-cash-paid-for-income-taxes-details" name="statement-statement-note-9-income-taxes-cash-paid-for-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-income-taxes-components-of-provision-for-income-tax-details" name="statement-statement-note-9-income-taxes-components-of-provision-for-income-tax-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-income-taxes-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-9-income-taxes-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-income-taxes-income-loss-before-income-taxes-details" name="statement-statement-note-9-income-taxes-income-loss-before-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-income-taxes-reconciliation-of-income-tax-details" name="statement-statement-note-9-income-taxes-reconciliation-of-income-tax-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-income-taxes-reconciliation-of-income-tax-details-parentheticals" name="statement-statement-note-9-income-taxes-reconciliation-of-income-tax-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="lpth_statement-statement-note-9-income-taxes-tables" name="statement-statement-note-9-income-taxes-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>
