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  <xsd:element abstract="true" id="aaoi_NewTaipeiCityAgreementWithInternationalGamesSystemCoMember" name="NewTaipeiCityAgreementWithInternationalGamesSystemCoMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_NewTaipeiCityLeaseAgreementMember" name="NewTaipeiCityLeaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_NingboChinaMember" name="NingboChinaMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_NotesPayableAndLongtermDebtCurrent" name="NotesPayableAndLongtermDebtCurrent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="aaoi_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_Nt100mCreditLineMember" name="Nt100mCreditLineMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_NumberOfCustomers" name="NumberOfCustomers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_NumberOfPatentsIssued" name="NumberOfPatentsIssued" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element id="aaoi_OperatingLossCarryforwardsCarryforwardPeriod" name="OperatingLossCarryforwardsCarryforwardPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_OperatingLossCarryforwardsNotSubjectToExpiration" name="OperatingLossCarryforwardsNotSubjectToExpiration" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="aaoi_OperatingLossCarryforwardsSubjectToExpiration" name="OperatingLossCarryforwardsSubjectToExpiration" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="aaoi_OracleMember" name="OracleMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_PercentageOfRevenue" name="PercentageOfRevenue" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_PolicyTable" name="PolicyTable" nillable="true" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_PrimeWorldInternationalHoldingsLtdPrimeWorldMember" name="PrimeWorldInternationalHoldingsLtdPrimeWorldMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_PrimeWorldMember" name="PrimeWorldMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ProceedsFromIssuanceOfConvertibleSeniorNotesNetOfDebtIssuanceCosts" name="ProceedsFromIssuanceOfConvertibleSeniorNotesNetOfDebtIssuanceCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ProceedsFromPaymentsForStockOptionsExercised" name="ProceedsFromPaymentsForStockOptionsExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ProductWarrantyExtensionPeriod" name="ProductWarrantyExtensionPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_PropertyInSugarLandTexasLeaseAgreementMember" name="PropertyInSugarLandTexasLeaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_PropertyPantAndEquipmentNetBeforeConstructionInProgressAndLand" name="PropertyPantAndEquipmentNetBeforeConstructionInProgressAndLand" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="aaoi_RaymondJamesAndAssociatesAndSalesAgentsMember" name="RaymondJamesAndAssociatesAndSalesAgentsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_RaymondJamesAssociatesIncMember" name="RaymondJamesAssociatesIncMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_RegisteredDirectOfferingMember" name="RegisteredDirectOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_RenewedCzbCreditLineMember" name="RenewedCzbCreditLineMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_RenewedSpdCreditLineMember" name="RenewedSpdCreditLineMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_RentIncreaseDecreasePercentage" name="RentIncreaseDecreasePercentage" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_RestrictedCashAndCashEquivalentsFairValueDisclosure" name="RestrictedCashAndCashEquivalentsFairValueDisclosure" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="aaoi_SPDBankMember" name="SPDBankMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_SalesAgentsMember" name="SalesAgentsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ScheduleOfStockSoldInOfferingTableTextBlock" name="ScheduleOfStockSoldInOfferingTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ScheduleOfUsefulLivesOfPropertyPlantAndEquipmentTableTextBlock" name="ScheduleOfUsefulLivesOfPropertyPlantAndEquipmentTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_SecondATMOfferingMember" name="SecondATMOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_ShanghaiPudongDevelopmentBankCoLtdMember" name="ShanghaiPudongDevelopmentBankCoLtdMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_SharebasedCompensationArrangementByShareBasedPaymentAwardPerformanceAwardValuePercentageOfBasedAmount" name="SharebasedCompensationArrangementByShareBasedPaymentAwardPerformanceAwardValuePercentageOfBasedAmount" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="aaoi_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueCancelled" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueCancelled" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="aaoi_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueExercised" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueExercised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="aaoi_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGranted" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsAggregateIntrinsicValueGranted" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="aaoi_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestWeightedAverageGrantDateFairValue" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedAndExpectedToVestWeightedAverageGrantDateFairValue" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageSharePriceOnDateOfRelease" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageSharePriceOnDateOfRelease" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_SharebasedCompensationArrangementBySharebasedPaymentAwardNonoptionEquityInstrumentsVestedAndExpectedToVest" name="SharebasedCompensationArrangementBySharebasedPaymentAwardNonoptionEquityInstrumentsVestedAndExpectedToVest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ShippingAndHandlingCostsPolicyTextBlock" name="ShippingAndHandlingCostsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_SubsidiaryOfAmazonMember" name="SubsidiaryOfAmazonMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_TaishinCreditFacilityMember" name="TaishinCreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_TaishinInternationalBankMember" name="TaishinInternationalBankMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_TaxesNotificationOfAuditResultMember" name="TaxesNotificationOfAuditResultMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_TelecomMember" name="TelecomMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_The200MCreditFacilityMember" name="The200MCreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_The50MCreditFacilityMember" name="The50MCreditFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_The5250ConvertibleSeniorNotesDue2026Member" name="The5250ConvertibleSeniorNotesDue2026Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_The5PercentConvertibleSeniorNotesDue2024Member" name="The5PercentConvertibleSeniorNotesDue2024Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_TheSPDCreditLineMember" name="TheSPDCreditLineMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_ThirdAtmOfferingMember" name="ThirdAtmOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_Us2mCreditLineMember" name="Us2mCreditLineMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ValuationAllowanceChangeChargedToCurrencyTranslationAdjustment" name="ValuationAllowanceChangeChargedToCurrencyTranslationAdjustment" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ValuationAllowanceChangeInOtherAdjustments" name="ValuationAllowanceChangeInOtherAdjustments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="aaoi_ValuationAllowanceDeferredTaxAssetChangeChargedToExpenseIncome" name="ValuationAllowanceDeferredTaxAssetChangeChargedToExpenseIncome" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-b-summary-of-significant-accounting-policies-product-warrant-liability-details" name="statement-statement-note-b-summary-of-significant-accounting-policies-product-warrant-liability-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-b-summary-of-significant-accounting-policies-property-plant-and-equipment-details" name="statement-statement-note-b-summary-of-significant-accounting-policies-property-plant-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-b-summary-of-significant-accounting-policies-tables" name="statement-statement-note-b-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-c-revenue-recognition-revenue-by-major-product-category-details" name="statement-statement-note-c-revenue-recognition-revenue-by-major-product-category-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-c-revenue-recognition-summary-of-valuation-assumption-of-warrant-details" name="statement-statement-note-c-revenue-recognition-summary-of-valuation-assumption-of-warrant-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-c-revenue-recognition-tables" name="statement-statement-note-c-revenue-recognition-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-d-leases-components-of-lease-expense-details" name="statement-statement-note-d-leases-components-of-lease-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-d-leases-maturities-of-lease-liabilities-details" name="statement-statement-note-d-leases-maturities-of-lease-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-d-leases-tables" name="statement-statement-note-d-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-e-cash-cash-equivalents-and-restricted-cash-summary-of-cash-cash-equivalents-and-restricted-cash-details" name="statement-statement-note-e-cash-cash-equivalents-and-restricted-cash-summary-of-cash-cash-equivalents-and-restricted-cash-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-e-cash-cash-equivalents-and-restricted-cash-tables" name="statement-statement-note-e-cash-cash-equivalents-and-restricted-cash-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-f-earnings-per-share-computation-of-basic-and-diluted-net-income-loss-per-share-details" name="statement-statement-note-f-earnings-per-share-computation-of-basic-and-diluted-net-income-loss-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-f-earnings-per-share-potentially-dilutive-securities-excluded-from-diluted-net-income-loss-per-share-details" name="statement-statement-note-f-earnings-per-share-potentially-dilutive-securities-excluded-from-diluted-net-income-loss-per-share-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-f-earnings-per-share-tables" name="statement-statement-note-f-earnings-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-g-inventories-inventories-details" name="statement-statement-note-g-inventories-inventories-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-g-inventories-tables" name="statement-statement-note-g-inventories-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-h-property-plant-and-equipment-property-plant-and-equipment-details" name="statement-statement-note-h-property-plant-and-equipment-property-plant-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-h-property-plant-and-equipment-tables" name="statement-statement-note-h-property-plant-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-i-intangible-assets-finitelived-intangible-assets-details" name="statement-statement-note-i-intangible-assets-finitelived-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-i-intangible-assets-future-amortization-expense-details" name="statement-statement-note-i-intangible-assets-future-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-i-intangible-assets-tables" name="statement-statement-note-i-intangible-assets-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-j-fair-value-of-financial-instruments-financial-instruments-measured-at-fair-value-on-a-recurring-basis-details" name="statement-statement-note-j-fair-value-of-financial-instruments-financial-instruments-measured-at-fair-value-on-a-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-j-fair-value-of-financial-instruments-tables" name="statement-statement-note-j-fair-value-of-financial-instruments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-k-notes-payable-and-longterm-debt-schedule-of-notes-payable-and-longterm-debt-details" name="statement-statement-note-k-notes-payable-and-longterm-debt-schedule-of-notes-payable-and-longterm-debt-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-k-notes-payable-and-longterm-debt-schedule-of-notes-payable-and-longterm-debt-details-parentheticals" name="statement-statement-note-k-notes-payable-and-longterm-debt-schedule-of-notes-payable-and-longterm-debt-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-k-notes-payable-and-longterm-debt-tables" name="statement-statement-note-k-notes-payable-and-longterm-debt-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-l-convertible-senior-notes-schedule-of-carrying-value-of-convertible-senior-notes-details" name="statement-statement-note-l-convertible-senior-notes-schedule-of-carrying-value-of-convertible-senior-notes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-l-convertible-senior-notes-schedule-of-interest-expense-details" name="statement-statement-note-l-convertible-senior-notes-schedule-of-interest-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-l-convertible-senior-notes-tables" name="statement-statement-note-l-convertible-senior-notes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-m-accrued-liabilities-accrued-liabilities-details" name="statement-statement-note-m-accrued-liabilities-accrued-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-m-accrued-liabilities-tables" name="statement-statement-note-m-accrued-liabilities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-n-other-income-and-expense-other-income-and-expense-details" name="statement-statement-note-n-other-income-and-expense-other-income-and-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-n-other-income-and-expense-tables" name="statement-statement-note-n-other-income-and-expense-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-o-income-taxes-income-loss-from-operations-before-income-taxes-details" name="statement-statement-note-o-income-taxes-income-loss-from-operations-before-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-o-income-taxes-net-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-o-income-taxes-net-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-o-income-taxes-provision-for-income-tax-expense-benefit-details" name="statement-statement-note-o-income-taxes-provision-for-income-tax-expense-benefit-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-o-income-taxes-reconciliation-of-the-us-federal-income-tax-rate-details" name="statement-statement-note-o-income-taxes-reconciliation-of-the-us-federal-income-tax-rate-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-o-income-taxes-summary-of-valuation-of-allowance-details" name="statement-statement-note-o-income-taxes-summary-of-valuation-of-allowance-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-o-income-taxes-tables" name="statement-statement-note-o-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-o-income-taxes-unrecognized-tax-benefits-details" name="statement-statement-note-o-income-taxes-unrecognized-tax-benefits-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-p-sharebased-compensation-performance-stock-unitawards-activity-details" name="statement-statement-note-p-sharebased-compensation-performance-stock-unitawards-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-p-sharebased-compensation-restricted-stock-unitawards-activity-details" name="statement-statement-note-p-sharebased-compensation-restricted-stock-unitawards-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-p-sharebased-compensation-sharebased-compensation-details" name="statement-statement-note-p-sharebased-compensation-sharebased-compensation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-p-sharebased-compensation-tables" name="statement-statement-note-p-sharebased-compensation-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-q-stockholders-equity-stock-sold-in-offering-details" name="statement-statement-note-q-stockholders-equity-stock-sold-in-offering-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-q-stockholders-equity-tables" name="statement-statement-note-q-stockholders-equity-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-r-segment-and-geographic-information-asset-information-by-geographic-region-details" name="statement-statement-note-r-segment-and-geographic-information-asset-information-by-geographic-region-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-r-segment-and-geographic-information-revenue-information-by-geographic-region-details" name="statement-statement-note-r-segment-and-geographic-information-revenue-information-by-geographic-region-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-r-segment-and-geographic-information-schedule-of-segment-information-details" name="statement-statement-note-r-segment-and-geographic-information-schedule-of-segment-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_statement-statement-note-r-segment-and-geographic-information-tables" name="statement-statement-note-r-segment-and-geographic-information-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="aaoi_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>
