<?xml version="1.0" encoding="us-ascii"?>
<!-- DFIN ActiveDisclosure(SM) XBRL Schema Document - http://www.dfinsolutions.com/ -->
<!-- Creation Date      : 2021-02-16T21:57:06.7569034+00:00 -->
<!-- Version            : 5.0.1.571 -->
<!-- Package ID         : e569a9b3ef9d48bb922b0d04e42ceb90 -->
<!-- Copyright (c) 2021 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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  <xsd:element id="oled_OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" name="OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearTwo" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearThree" name="OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearThree" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearFour" name="OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearFive" name="OtherFiniteLivedIntangibleAssetsAmortizationExpenseYearFive" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_OtherFiniteLivedIntangibleAssetsAmortizationExpenseThereafter" name="OtherFiniteLivedIntangibleAssetsAmortizationExpenseThereafter" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_AccruedResearchAndDevelopmentAgreementFees" name="AccruedResearchAndDevelopmentAgreementFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_AccruedConsultingFeesCurrent" name="AccruedConsultingFeesCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_ResearchAndDevelopmentArrangementRoyaltyRateForLicensedProductsSoldByCompany" name="ResearchAndDevelopmentArrangementRoyaltyRateForLicensedProductsSoldByCompany" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_ResearchAndDevelopmentArrangementRoyaltyRateForLicensedProductsSoldByCompanysSublicenses" name="ResearchAndDevelopmentArrangementRoyaltyRateForLicensedProductsSoldByCompanysSublicenses" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_ResearchAndDevelopmentArrangementMaximumObligation" name="ResearchAndDevelopmentArrangementMaximumObligation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_LongTermPurchaseCommitmentPercentOfServicesPayableInCashOrShares" name="LongTermPurchaseCommitmentPercentOfServicesPayableInCashOrShares" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="oled_NewOledMaterialsAgreementAndOledMaterialsAgreementMember" name="NewOledMaterialsAgreementAndOledMaterialsAgreementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_ResearchAndDevelopmentExpenseCredit" name="ResearchAndDevelopmentExpenseCredit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_NumberOfBoardMembersElectedByClassShareholders" name="NumberOfBoardMembersElectedByClassShareholders" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DeferredCompensationArrangementWithEmployeesAndNonEmployeesShareBasedPaymentsLineItems" name="DeferredCompensationArrangementWithEmployeesAndNonEmployeesShareBasedPaymentsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_ScheduleOfDeferredCompensationArrangementWithEmployeesAndNonEmployeesShareBasedPaymentsTable" name="ScheduleOfDeferredCompensationArrangementWithEmployeesAndNonEmployeesShareBasedPaymentsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_EmployeesAndNonEmployeeMembersOfScientificAdvisoryBoardMember" name="EmployeesAndNonEmployeeMembersOfScientificAdvisoryBoardMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_MembersOfScientificAdvisoryBoardMember" name="MembersOfScientificAdvisoryBoardMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_ManufacturingExpenseMember" name="ManufacturingExpenseMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_NonEmployeeMembersOfScientificAdvisoryBoardMember" name="NonEmployeeMembersOfScientificAdvisoryBoardMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_IncrementalPerformanceBasedMember" name="IncrementalPerformanceBasedMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_PerformanceBasedVestingRequirementMember" name="PerformanceBasedVestingRequirementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_MarketBasedVestingRequirementMember" name="MarketBasedVestingRequirementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_CompanyPerformanceBasedVestingRequirementMember" name="CompanyPerformanceBasedVestingRequirementMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_StockIssuedDuringPeriodSharesShareBasedCompensationSharesWithheldForEmployeeTaxes" name="StockIssuedDuringPeriodSharesShareBasedCompensationSharesWithheldForEmployeeTaxes" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_StockIssuedDuringPeriodValueShareBasedCompensationSharesWithheldForEmployeeTaxes" name="StockIssuedDuringPeriodValueShareBasedCompensationSharesWithheldForEmployeeTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_EmployeeStockPurchasePlanESPPSharesInESPP" name="EmployeeStockPurchasePlanESPPSharesInESPP" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="oled_EmployeeStockPurchasePlanMember" name="EmployeeStockPurchasePlanMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_EmployeeStockPurchasePlanESPPPurchasePeriod" name="EmployeeStockPurchasePlanESPPPurchasePeriod" type="us-types:durationStringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_EmployeeStockPurchasePlanESPPPercentageOfMarketValue" name="EmployeeStockPurchasePlanESPPPercentageOfMarketValue" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_EmployeeStockPurchasePlanESPPMaximumAllocationOfBaseCompensation" name="EmployeeStockPurchasePlanESPPMaximumAllocationOfBaseCompensation" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_EmployeeStockPurchasePlanESPPMaximumSharesOnPurchaseDate" name="EmployeeStockPurchasePlanESPPMaximumSharesOnPurchaseDate" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_EmployeeStockPurchasePlanESPPMaximumValuePerCalendarYear" name="EmployeeStockPurchasePlanESPPMaximumValuePerCalendarYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_EmployeeStockPurchasePlanESPPCompensationExpense" name="EmployeeStockPurchasePlanESPPCompensationExpense" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_DefinedBenefitPlansNumberOfParticipants" name="DefinedBenefitPlansNumberOfParticipants" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansFactorUsedToDetermineAnnualBaseSalary" name="DefinedBenefitPlansFactorUsedToDetermineAnnualBaseSalary" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansAnnualBaseSalaryPeriod" name="DefinedBenefitPlansAnnualBaseSalaryPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansAgeOfParticipant" name="DefinedBenefitPlansAgeOfParticipant" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansMinimumPeriodOfService" name="DefinedBenefitPlansMinimumPeriodOfService" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansBenefitPercentageTierOne" name="DefinedBenefitPlansBenefitPercentageTierOne" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansBenefitPercentageTierTwo" name="DefinedBenefitPlansBenefitPercentageTierTwo" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansBenefitPercentageTierThree" name="DefinedBenefitPlansBenefitPercentageTierThree" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansMinimumPeriodOfServiceForProratedBenefit" name="DefinedBenefitPlansMinimumPeriodOfServiceForProratedBenefit" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansFactorUsedToDetermineProratedBenefit" name="DefinedBenefitPlansFactorUsedToDetermineProratedBenefit" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansInstallmentPeriod" name="DefinedBenefitPlansInstallmentPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansBenefitPercentageForSpecialParticipants" name="DefinedBenefitPlansBenefitPercentageForSpecialParticipants" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansThresholdOfBenefitObligationAtWhichActuarialLossesAreAmortized" name="DefinedBenefitPlansThresholdOfBenefitObligationAtWhichActuarialLossesAreAmortized" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="oled_DefinedBenefitPlansExpectedFutureBenefitPaymentsAfterFiveFiscalYearsThereafter" name="DefinedBenefitPlansExpectedFutureBenefitPaymentsAfterFiveFiscalYearsThereafter" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_NumberOfExecutiveOfficersUnderAgreement" name="NumberOfExecutiveOfficersUnderAgreement" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="oled_NumberOfEmployeesUnderAgreement" name="NumberOfEmployeesUnderAgreement" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="oled_MultipleOfSumOfAverageAnnualBaseSalaryAndBonusAgreementTerms" name="MultipleOfSumOfAverageAnnualBaseSalaryAndBonusAgreementTerms" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" />
  <xsd:element id="oled_CommitmentWithExecutiveOfficersMember" name="CommitmentWithExecutiveOfficersMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_MajorCustomerAMember" name="MajorCustomerAMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_MajorCustomerBMember" name="MajorCustomerBMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_MajorCustomerCMember" name="MajorCustomerCMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_ExcludingNorthAmericaMember" name="ExcludingNorthAmericaMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_OtherNonUSMember" name="OtherNonUSMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_NumberOfSuppliersFromWhichChemicalMaterialsWerePurchased" name="NumberOfSuppliersFromWhichChemicalMaterialsWerePurchased" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_DeferredIncomeTaxExpenseBenefitBeforeChangeinValuationAllowance" name="DeferredIncomeTaxExpenseBenefitBeforeChangeinValuationAllowance" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_EffectiveIncomeTaxRateReconciliationChangeInAccrualsAndReservesPercent" name="EffectiveIncomeTaxRateReconciliationChangeInAccrualsAndReservesPercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_EffectiveIncomeTaxRateReconciliationDeductionShareBasedCompensationCostPercent" name="EffectiveIncomeTaxRateReconciliationDeductionShareBasedCompensationCostPercent" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_EffectiveIncomeTaxRateReconciliationUSTaxCutsAndJobsAct" name="EffectiveIncomeTaxRateReconciliationUSTaxCutsAndJobsAct" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_TaxCreditAndOperatingLossCarryforwardsLineItems" name="TaxCreditAndOperatingLossCarryforwardsLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_TaxCreditAndOperatingLossCarryforwardsTable" name="TaxCreditAndOperatingLossCarryforwardsTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_DeferredTaxAssetsCapitalizedTechnologyLicenseAndPatents" name="DeferredTaxAssetsCapitalizedTechnologyLicenseAndPatents" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_DeferredTaxAssetsCapitalizedResearchExpenditures" name="DeferredTaxAssetsCapitalizedResearchExpenditures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_DeferredTaxAssetsRetirementPlan" name="DeferredTaxAssetsRetirementPlan" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_IncomeTaxesLineItems" name="IncomeTaxesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_IncomeTaxesTable" name="IncomeTaxesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_AllocationOfWithholdingToNonKoreanPatentsMember" name="AllocationOfWithholdingToNonKoreanPatentsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_WithholdingAndInterestForLicensingAndRoyaltyPayments" name="WithholdingAndInterestForLicensingAndRoyaltyPayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_WithholdingAndInterestForLicencingAndRoyaltyPaymentsPeriod" name="WithholdingAndInterestForLicencingAndRoyaltyPaymentsPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMinimum" name="StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMinimum" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMaximum" name="StateAndForeignIncomeTaxReturnsSubjectToExaminationPeriodMaximum" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_WithholdingTaxRateForRoyaltyPayments" name="WithholdingTaxRateForRoyaltyPayments" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_PercentageOfRevenueRecordedFromSaleOfMaterials" name="PercentageOfRevenueRecordedFromSaleOfMaterials" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_PercentageOfRevenueRecordedFromProvisionOfServices" name="PercentageOfRevenueRecordedFromProvisionOfServices" type="num:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_UnbilledReceivablesNoncurrent" name="UnbilledReceivablesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_ContractExpirationYear" name="ContractExpirationYear" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" />
  <xsd:element id="oled_BacklogAssociatedWithCommittedPurchaseOrdersFromCustomers" name="BacklogAssociatedWithCommittedPurchaseOrdersFromCustomers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_NetIncreaseDecreaseInDeferredRevenue" name="NetIncreaseDecreaseInDeferredRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionForDeferredRevenue" name="CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionForDeferredRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_AdjustedBalanceDeferredRevenue" name="AdjustedBalanceDeferredRevenue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_UnbilledReceivablesIncreaseDecreaseNet" name="UnbilledReceivablesIncreaseDecreaseNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit" />
  <xsd:element id="oled_IncreaseDecreaseInUnbilledReceivablesAbstract" name="IncreaseDecreaseInUnbilledReceivablesAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true" />
  <xsd:element id="oled_CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionForUnbilledReceivables" name="CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoptionForUnbilledReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
  <xsd:element id="oled_AdjustedBalanceUnbilledReceivables" name="AdjustedBalanceUnbilledReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit" />
</xsd:schema>
