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    <element id="AAOI_NotePayable2Member" name="NotePayable2Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_USBankLoansMember" name="USBankLoansMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_ChinaBanksMember" name="ChinaBanksMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_TaiwanMember" name="TaiwanMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_Plan2013Member" name="Plan2013Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_Plan1998Member" name="Plan1998Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_Plan2000Member" name="Plan2000Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_Plan2004Member" name="Plan2004Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_Plan2006Member" name="Plan2006Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_CashPaidFor" name="CashPaidFor" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_ConversionOfShareholdersLoanToPreferredStock" name="ConversionOfShareholdersLoanToPreferredStock" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_ScheduleOfProFormaEarningsPerShareBasicAndDilutedTableTextBlock" name="ScheduleOfProFormaEarningsPerShareBasicAndDilutedTableTextBlock" nillable="true" xbrli:periodType="duration" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_FairValueOfFinancialInstrumentsDetailsAbstract" name="FairValueOfFinancialInstrumentsDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_NumeratorAbstract" name="NumeratorAbstract" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_DenominatorAbstract" name="DenominatorAbstract" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_WeightedAverageSharesUsedToComputeNetIncomeLossPerShareAbstract" name="WeightedAverageSharesUsedToComputeNetIncomeLossPerShareAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_NetIncomeLossPerShare" name="NetIncomeLossPerShare" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_NumberOfSharesUsedToComputeNetIncomeLossPerShare" name="NumberOfSharesUsedToComputeNetIncomeLossPerShare" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_NumberOfSharesUsedToComputeProFormaNetIncomeLossPerShare" name="NumberOfSharesUsedToComputeProFormaNetIncomeLossPerShare" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_ProFormaNetIncomeLossPerShare" name="ProFormaNetIncomeLossPerShare" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_PotentiallyDilutiveSecuritiesDetailsAbstract" name="PotentiallyDilutiveSecuritiesDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_InventoryDetailsAbstract" name="InventoryDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_InventoryNarrativeAbstract" name="InventoryNarrativeAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_LowerOfCostOrMarketAdjustmentForInventory" name="LowerOfCostOrMarketAdjustmentForInventory" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_PropertyPlantAndEquipmentDetailsAbstract" name="PropertyPlantAndEquipmentDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_PropertyPlantAndEquipmentNarrativeAbstract" name="PropertyPlantAndEquipmentNarrativeAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_NotesPayableAndLongtermDebtDetailsAbstract" name="NotesPayableAndLongtermDebtDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_DebtInstrumentDomain" name="DebtInstrumentDomain" abstract="true" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_NotesPayableAndLongtermDebtNarrativeAbstract" name="NotesPayableAndLongtermDebtNarrativeAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_BankAcceptancePayable" name="BankAcceptancePayable" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_AccruedLiabilitiesDetailsAbstract" name="AccruedLiabilitiesDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_AccruedPayments" name="AccruedPayments" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_AccruedCommission" name="AccruedCommission" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_OtherIncomeAndExpenseDetailsAbstract" name="OtherIncomeAndExpenseDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_GovernmentSubsidyIncome" name="GovernmentSubsidyIncome" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_EmployeeeStockbasedCompensationDetailsAbstract" name="EmployeeeStockbasedCompensationDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_OptionActivityDetailsAbstract" name="OptionActivityDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_NumberOfShares" name="NumberOfShares" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_ExercisePrice" name="ExercisePrice" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_StockbasedCompensatinNarrativeAbstract" name="StockbasedCompensatinNarrativeAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_ConvertiblePreferredStockDetailsAbstract" name="ConvertiblePreferredStockDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_StockholdersEquityNarrativeAbstract" name="StockholdersEquityNarrativeAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="AAOI_SegmentAndGeographicInformationDetailsAbstract" name="SegmentAndGeographicInformationDetailsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
</schema>
