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    <element id="REFR_ProceedsFromSaleOfCommonStockAndWarrants" name="ProceedsFromSaleOfCommonStockAndWarrants" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_DisclosureLicenseAndOtherAgreementsAbstract" name="DisclosureLicenseAndOtherAgreementsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_LicenseAndOtherAgreementsTextBlock" name="LicenseAndOtherAgreementsTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_DisclosureRightsPlanAbstract" name="DisclosureRightsPlanAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_RightsPlanDisclosureTextBlock" name="RightsPlanDisclosureTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_RestrictedStockPolicyTextBlock" name="RestrictedStockPolicyTextBlock" nillable="true" xbrli:periodType="duration" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_WorkingCapital" name="WorkingCapital" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_NonrecurringCashExpenses" name="NonrecurringCashExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_RoyaltyRateOnSellingPrice" name="RoyaltyRateOnSellingPrice" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_RecognizedBenefitMeasured" name="RecognizedBenefitMeasured" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_DeferredTaxAssetsLeaseLiability" name="DeferredTaxAssetsLeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_DeferredTaxAssetsAmortization" name="DeferredTaxAssetsAmortization" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_AmortizedCostTermDescription" name="AmortizedCostTermDescription" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_CorporateMinimumTaxRate" name="CorporateMinimumTaxRate" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_ExciseTaxOnCorporateStockRate" name="ExciseTaxOnCorporateStockRate" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_OperatingLossCarryforwardsExpirationDescription" name="OperatingLossCarryforwardsExpirationDescription" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsIssuedInPeriodWeightedAverageExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsIssuedInPeriodWeightedAverageExercisePrice" nillable="true" xbrli:periodType="duration" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_WarrantsAndNonemployeeOptionsVestedTerm" name="WarrantsAndNonemployeeOptionsVestedTerm" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_RoyaltyEarnedPercentage" name="RoyaltyEarnedPercentage" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_LesseeOperatingLeaseLiabilityPaymentsDueYearTwoAndThree" name="LesseeOperatingLeaseLiabilityPaymentsDueYearTwoAndThree" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_LesseeOperatingLeaseLiabilityPaymentsDueYearFourAndFive" name="LesseeOperatingLeaseLiabilityPaymentsDueYearFourAndFive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_LeaseExpirationTerm" name="LeaseExpirationTerm" nillable="true" xbrli:periodType="duration" type="xbrli:durationItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_PercentageOfAcquisitionThresholdInRightsAgreement" name="PercentageOfAcquisitionThresholdInRightsAgreement" nillable="true" xbrli:periodType="duration" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_DiscountPriceOfStock" name="DiscountPriceOfStock" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_AcquiringAssetsPercent" name="AcquiringAssetsPercent" nillable="true" xbrli:periodType="instant" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_RightsPlanExpireDate" name="RightsPlanExpireDate" nillable="true" xbrli:periodType="duration" type="xbrli:dateItemType" substitutionGroup="xbrli:item" />
    <element id="REFR_RightsRedemptionPricePerShare" name="RightsRedemptionPricePerShare" nillable="true" xbrli:periodType="instant" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" />
</schema>
