<?xml version="1.0" encoding="utf-8"?>
<!--Generated by DataTracks version 3.0 on 13-August-2018 [03:36:49] {PM} EST - www.datatracks.com-->
<schema targetNamespace="http://www.inradoptics.com/20180630" elementFormDefault="qualified" xmlns:inrd="http://www.inradoptics.com/20180630" xmlns="http://www.w3.org/2001/XMLSchema" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xl="http://www.xbrl.org/2003/XLink" xmlns:us-gaap="http://fasb.org/us-gaap/2018-01-31" xmlns:country="http://xbrl.sec.gov/country/2017-01-31" xmlns:currency="http://xbrl.sec.gov/currency/2017-01-31" xmlns:dei="http://xbrl.sec.gov/dei/2018-01-31" xmlns:exch="http://xbrl.sec.gov/exch/2018-01-31" xmlns:invest="http://xbrl.sec.gov/invest/2013-01-31" xmlns:naics="http://xbrl.sec.gov/naics/2017-01-31" xmlns:sic="http://xbrl.sec.gov/sic/2011-01-31" xmlns:us-types="http://fasb.org/us-types/2018-01-31" xmlns:stpr="http://xbrl.sec.gov/stpr/2018-01-31" xmlns:deprecated="http://www.xbrl.org/2009/arcrole/fact-explanatoryFact" xmlns:nonnum="http://www.xbrl.org/dtr/type/non-numeric" xmlns:num="http://www.xbrl.org/dtr/type/numeric" xmlns:srt="http://fasb.org/srt/2018-01-31">
<annotation>
<appinfo>
<link:roleType roleURI="http://www.inradoptics.com/role/DocumentAndEntityInformation" id="DocumentAndEntityInformation">
<link:definition>1001 - Document - Document And Entity Information</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/CondensedConsolidatedBalanceSheets" id="CondensedConsolidatedBalanceSheets">
<link:definition>1002 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/CondensedConsolidatedBalanceSheetsParenthetical" id="CondensedConsolidatedBalanceSheetsParenthetical">
<link:definition>1003 - Statement - CONDENSED CONSOLIDATED BALANCE SHEETS [Parenthetical]</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/CondensedConsolidatedStatementsOfOperations" id="CondensedConsolidatedStatementsOfOperations">
<link:definition>1004 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/CondensedConsolidatedStatementsOfCashFlows" id="CondensedConsolidatedStatementsOfCashFlows">
<link:definition>1005 - Statement - CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/SummaryOfSignificantAccountingPolicies" id="SummaryOfSignificantAccountingPolicies">
<link:definition>1006 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/Revenue" id="Revenue">
<link:definition>1007 - Disclosure - REVENUE</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/EquityCompensationProgramAndStockBasedCompensation" id="EquityCompensationProgramAndStockBasedCompensation">
<link:definition>1008 - Disclosure - EQUITY COMPENSATION PROGRAM AND STOCK BASED COMPENSATION</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/StockholdersEquity" id="StockholdersEquity">
<link:definition>1009 - Disclosure - STOCKHOLDERS' EQUITY</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/RelatedPartyTransactions" id="RelatedPartyTransactions">
<link:definition>1010 - Disclosure - RELATED PARTY TRANSACTIONS</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/OtherLongTermNotes" id="OtherLongTermNotes">
<link:definition>1011 - Disclosure - OTHER LONG TERM NOTES</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/SummaryOfSignificantAccountingPoliciesPolicies" id="SummaryOfSignificantAccountingPoliciesPolicies">
<link:definition>1012 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/SummaryOfSignificantAccountingPoliciesTables" id="SummaryOfSignificantAccountingPoliciesTables">
<link:definition>1013 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/RevenueTables" id="RevenueTables">
<link:definition>1014 - Disclosure - REVENUE (Tables)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/EquityCompensationProgramAndStockBasedCompensationTables" id="EquityCompensationProgramAndStockBasedCompensationTables">
<link:definition>1015 - Disclosure - EQUITY COMPENSATION PROGRAM AND STOCK BASED COMPENSATION (Tables)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/OtherLongTermNotesTables" id="OtherLongTermNotesTables">
<link:definition>1016 - Disclosure - OTHER LONG TERM NOTES (Tables)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/SummaryOfSignificantAccountingPoliciesDetails" id="SummaryOfSignificantAccountingPoliciesDetails">
<link:definition>1017 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/SummaryOfSignificantAccountingPoliciesDetails1" id="SummaryOfSignificantAccountingPoliciesDetails1">
<link:definition>1018 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 1)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/SummaryOfSignificantAccountingPoliciesDetailsTextual" id="SummaryOfSignificantAccountingPoliciesDetailsTextual">
<link:definition>1019 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Textual)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/RevenueDetails" id="RevenueDetails">
<link:definition>1020 - Disclosure - REVENUE (Details)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/RevenueDetailsTextual" id="RevenueDetailsTextual">
<link:definition>1021 - Disclosure - REVENUE (Details Textual)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/EquityCompensationProgramAndStockBasedCompensationDetails" id="EquityCompensationProgramAndStockBasedCompensationDetails">
<link:definition>1022 - Disclosure - EQUITY COMPENSATION PROGRAM AND STOCK BASED COMPENSATION (Details)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/EquityCompensationProgramAndStockBasedCompensationDetails1" id="EquityCompensationProgramAndStockBasedCompensationDetails1">
<link:definition>1023 - Disclosure - EQUITY COMPENSATION PROGRAM AND STOCK BASED COMPENSATION (Details 1)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/EquityCompensationProgramAndStockBasedCompensationDetails2" id="EquityCompensationProgramAndStockBasedCompensationDetails2">
<link:definition>1024 - Disclosure - EQUITY COMPENSATION PROGRAM AND STOCK BASED COMPENSATION (Details 2)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/EquityCompensationProgramAndStockBasedCompensationDetailsTextual" id="EquityCompensationProgramAndStockBasedCompensationDetailsTextual">
<link:definition>1025 - Disclosure - EQUITY COMPENSATION PROGRAM AND STOCK BASED COMPENSATION (Details Textual)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/StockholdersEquityDetailsTextual" id="StockholdersEquityDetailsTextual">
<link:definition>1026 - Disclosure - STOCKHOLDERS' EQUITY (Details Textual)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/RelatedPartyTransactionsDetailsTextual" id="RelatedPartyTransactionsDetailsTextual">
<link:definition>1027 - Disclosure - RELATED PARTY TRANSACTIONS (Details Textual)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/OtherLongTermNotesDetails" id="OtherLongTermNotesDetails">
<link:definition>1028 - Disclosure - OTHER LONG TERM NOTES (Details)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:roleType roleURI="http://www.inradoptics.com/role/OtherLongTermNotesDetailsTextual" id="OtherLongTermNotesDetailsTextual">
<link:definition>1029 - Disclosure - OTHER LONG TERM NOTES (Details Textual)</link:definition>
<link:usedOn>link:presentationLink</link:usedOn>
<link:usedOn>link:definitionLink</link:usedOn>
<link:usedOn>link:calculationLink</link:usedOn>
</link:roleType>
<link:linkbaseRef xlink:type="simple" xlink:href="inrd-20180630_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
<link:linkbaseRef xlink:type="simple" xlink:href="inrd-20180630_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
<link:linkbaseRef xlink:type="simple" xlink:href="inrd-20180630_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
<link:linkbaseRef xlink:type="simple" xlink:href="inrd-20180630_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" />
</appinfo>
</annotation>
<import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd" />
<import namespace="http://www.xbrl.org/2003/linkbase" schemaLocation="http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd" />
<import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd" />
<import namespace="http://fasb.org/us-gaap/2018-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd" />
<import namespace="http://xbrl.sec.gov/invest/2013-01-31" schemaLocation="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd" />
<import namespace="http://xbrl.sec.gov/country/2017-01-31" schemaLocation="http://xbrl.sec.gov/country/2017/country-2017-01-31.xsd" />
<import namespace="http://xbrl.sec.gov/currency/2017-01-31" schemaLocation="http://xbrl.sec.gov/currency/2017/currency-2017-01-31.xsd" />
<import namespace="http://xbrl.sec.gov/exch/2018-01-31" schemaLocation="https://xbrl.sec.gov/exch/2018/exch-2018-01-31.xsd" />
<import namespace="http://xbrl.sec.gov/naics/2017-01-31" schemaLocation="http://xbrl.sec.gov/naics/2017/naics-2017-01-31.xsd" />
<import namespace="http://xbrl.sec.gov/sic/2011-01-31" schemaLocation="http://xbrl.sec.gov/sic/2011/sic-2011-01-31.xsd" />
<import namespace="http://xbrl.sec.gov/stpr/2018-01-31" schemaLocation="https://xbrl.sec.gov/stpr/2018/stpr-2018-01-31.xsd" />
<import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd" />
<import namespace="http://www.xbrl.org/2009/role/net" schemaLocation="http://www.xbrl.org/lrr/role/net-2009-12-16.xsd" />
<import namespace="http://www.xbrl.org/2009/arcrole/fact-explanatoryFact" schemaLocation="http://www.xbrl.org/lrr/arcrole/factExplanatory-2009-12-16.xsd" />
<import namespace="http://xbrl.sec.gov/dei/2018-01-31" schemaLocation="https://xbrl.sec.gov/dei/2018/dei-2018-01-31.xsd" />
<import namespace="http://www.xbrl.org/dtr/type/numeric" schemaLocation="http://www.xbrl.org/dtr/type/numeric-2009-12-16.xsd" />
<import namespace="http://www.xbrl.org/dtr/type/non-numeric" schemaLocation="http://www.xbrl.org/dtr/type/nonNumeric-2009-12-16.xsd" />
<import namespace="http://fasb.org/us-types/2018-01-31" schemaLocation="http://xbrl.fasb.org/us-gaap/2018/elts/us-types-2018-01-31.xsd" />
<import namespace="http://fasb.org/srt/2018-01-31" schemaLocation="http://xbrl.fasb.org/srt/2018/elts/srt-2018-01-31.xsd" />
<element name="DocumentAndEntityInformationAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_DocumentAndEntityInformationAbstract" substitutionGroup="xbrli:item" />
<element name="ContractLiabilities" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="inrd_ContractLiabilities" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="BalanceSheetsParentheticalAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_BalanceSheetsParentheticalAbstract" substitutionGroup="xbrli:item" />
<element name="ScheduleOfReconciliationOfSharesUsedInCalculationOfBasicAndDilutedEarningsPerCommonShareTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_ScheduleOfReconciliationOfSharesUsedInCalculationOfBasicAndDilutedEarningsPerCommonShareTableTextBlock" substitutionGroup="xbrli:item" />
<element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedTableTextBlock" type="nonnum:textBlockItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsNonVestedTableTextBlock" substitutionGroup="xbrli:item" />
<element name="DilutiveSecuritiesEffectOnBasicEarningsPerShareDilutiveAccruedInterestOnConvertibleNotes" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_DilutiveSecuritiesEffectOnBasicEarningsPerShareDilutiveAccruedInterestOnConvertibleNotes" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="DilutiveSecuritiesEffectOnBasicEarningsPerShareDilutiveWarrants" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_DilutiveSecuritiesEffectOnBasicEarningsPerShareDilutiveWarrants" substitutionGroup="xbrli:item" xbrli:balance="credit" />
<element name="IncrementalCommonSharesAttributableToDilutiveEffectOfAccruedInterestOnConvertibleNotes" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_IncrementalCommonSharesAttributableToDilutiveEffectOfAccruedInterestOnConvertibleNotes" substitutionGroup="xbrli:item" />
<element name="SummaryOfSignificantAccountingPoliciesTable" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_SummaryOfSignificantAccountingPoliciesTable" substitutionGroup="xbrldt:hypercubeItem" />
<element name="SellingExpenseMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_SellingExpenseMember" substitutionGroup="xbrli:item" />
<element name="SummaryOfSignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_SummaryOfSignificantAccountingPoliciesLineItems" substitutionGroup="xbrli:item" />
<element name="IncreaseDecreaseInDeferredTaxAssets" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_IncreaseDecreaseInDeferredTaxAssets" substitutionGroup="xbrli:item" xbrli:balance="debit" />
<element name="AerospaceDefenseMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_AerospaceDefenseMember" substitutionGroup="xbrli:item" />
<element name="ProcessControlMetrologyMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_ProcessControlMetrologyMember" substitutionGroup="xbrli:item" />
<element name="LaserSystemsMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_LaserSystemsMember" substitutionGroup="xbrli:item" />
<element name="ScientificRdMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_ScientificRdMember" substitutionGroup="xbrli:item" />
<element name="PercentageOfRevenueFromProductsOrServices" type="num:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_PercentageOfRevenueFromProductsOrServices" substitutionGroup="xbrli:item" />
<element name="ClarexMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_ClarexMember" substitutionGroup="xbrli:item" />
<element name="AffiliateOfClarexMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_AffiliateOfClarexMember" substitutionGroup="xbrli:item" />
<element name="WarrantsToPurchaseCommonStockNumberOfSharesPerWarrant" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="inrd_WarrantsToPurchaseCommonStockNumberOfSharesPerWarrant" substitutionGroup="xbrli:item" />
<element name="UsSmallBusinessAdministrationNotePayableMember" type="nonnum:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="inrd_UsSmallBusinessAdministrationNotePayableMember" substitutionGroup="xbrli:item" />
</schema>