50883
                                7
                                                   Exhibit 4.1(b)
                                         REDI Loan Number 95-13-A


                      STATE OF SOUTH DAKOTA
                  BOARD OF ECONOMIC DEVELOPMENT


                       SECURITY AGREEMENT

     The undersigned Debtor (s) hereby grants to
           SOUTH DAKOTA BOARD OF ECONOMIC DEVELOPMENT
              711 Wells Avenue, Pierre, S.D.  57501
"Lender", a Security Interest in the following described property
"Collateral":
     
          All machinery and equipment of Debtor described on
          Exhibit A attached hereto together with all
          accessions thereto and all substitutions and
          replacements thereof and parts therefor.
     
          All proceeds and products of all of the foregoing,
     
     to secure payment to the Lender at the address stated
     above of all notes of Debtor concurrently delivered
     herewith, or heretofore or hereafter delivered to or
     purchased or otherwise acquired by the Lender and all
     other liabilities and indebtedness of Debtor to the
     Lender, due or to become due, direct or indirect,
     absolute or contingent, joint or several, howsoever
     created, arising or evidenced, now existing or
     hereafter at any time created, arising or incurred
     (hereinafter called "Secured Obligations").
     
          INFORMATIONAL (Check one or more).
     
         The address of the Debtor,       X  Such address is
     below, is his residence.            Debtor's chief
     place of business
     
          Such address is where the       X  Debtor is a
     Collateral is kept                  non-resident of
                                         South Dakota
     
          USE OF PROPERTY:  Debtor warrants, covenants and
     agrees that:  The property is or is to be used by
     Debtor primarily (check applicable):
     
     1. In business:   X  equipment         inventory
     
     
     2. For personal, family, or household use ___
     
     
     3. In farming operations:   ___ equipment     ___ farm
     products
     
          PURPOSE:  (check if applicable) The security
     interest herein is given on this collateral for a
     purchase money loan: ___
     
               Debtor warrants, represents and agrees that:
     
     1.  The Collateral is or will be kept at Aberdeen, SD
     and will not be removed from such location or locations
     unless, prior to any such removal, Debtor has given written
     notice to the Lender of the location or locations to which
     Debtor desires to remove the Collateral and the Lender has
     given written consent to such removal.
     
     2.  Debtor has or will acquire title to and will at all
     times keep the Collateral free of all liens and
     encumbrances, except the Security Interest created hereby
     and liens held by other lenders providing financing for the
     SD project, and has full power and authority to execute this
     Security Agreement, to perform Debtor's obligations
     hereunder and to subject the Collateral to the Security
     Interest created hereby.  No financing statement covering
     all or any part of the Collateral, except any which may have
     been filed by the Lender and other permitted lienholders, is
     on file at any public office.
     
     3.  Debtor will at any time or times hereafter execute such
     financing statements and other instruments and perform such
     acts as the Lender may request to establish and maintain a
     valid Security Interest in the Collateral, and will pay all
     costs of filing and recording.
     4.  Debtor will keep the Collateral and all lands, plants,
     buildings, machinery, equipment and other property now or
     hereafter at any time owned or used by Borrower in
     connection with the manufacture, processing, production,
     storage, sale or lease of the Collateral, in good condition
     and insured against such risks and in such amounts as the
     Lender may request, and with an insurance company or
     companies satisfactory to the Lender, the policies to
     protect the Lender as his interest may appear and to be
     delivered to the Lender upon request.
     
     5.  Upon default by Debtor in any of the preceding
     agreements, the Lender at his option may
     
               (i)  effect such insurance and repairs and pay the
               premiums therefor and the costs thereof and
     
               (ii) pay and discharge any taxes, liens, and
               encumbrances on the Collateral.  All sums so
               advanced or paid by the Lender shall be payable by
               the Debtor on demand with interest at the highest
               rate allowed by law and shall be part of the
               Secured Obligations.
     
     6.  Debtor will not sell, lease or otherwise dispose of the
     Collateral other than in the ordinary course of business at
     prices constituting the then fair market value thereof, and
     will at all times during the term hereof maintain the
     inventory at such value as Lender may from time to time
     demand.
     
     7.  Lender shall have the authority, but shall not be
     obligated to:
     
               (a)  place on any Chattel Paper received as
               Proceeds a notation or legend showing the Lender's
               Security Interest;
     
               (b)  in the name of the Debtor or otherwise, to
               demand, collect, receive and receipt for,
               compound, compromise, settle and give acquittance
               for, and  prosecute and discontinue any suits or
               proceedings in respect of any or all of the
               Collateral;
     
               (c)  take any action which the Lender may deem
               necessary or desirable in order to realize on the
               Collateral, including, without limitation, the
               power to perform any contract, to endorse in the
               name of Debtor any checks, drafts, note or other
               instruments or documents received in payment for
               or on account of the Collateral;
     
               (d)  after any default, to enter upon and into and
               take possession of all or such part or parts of
               the properties of Debtor, including lands, plants,
               buildings, machinery, equipment and other property
               as may be necessary or appropriate in the judgment
               of the Lender to permit or enable the Lender to
               manufacture, produce, process, store or sell or
               complete the manufacture, production, processing,
               storing or sale of all or any part of the
               Collateral, as the Lender may elect, and to use
               and operate said properties for said purposes and
               for such length of time as the Lender may deem
               necessary or appropriate for said purposes without
               the payment of any compensation to Debtor
               therefor.
     
     8.  Debtor will keep accurate books, records and accounts
     with respect to the Collateral, and with respect to the
     general business of Debtor, and will make the same available
     to the Lender at its request for examination and inspection;
     and will make and render to the Lender such reports,
     accountings and statements as the Lender from time to time
     may request with respect to the Collateral; and will permit
     any authorized representative of the Lender to examine and
     inspect, during normal business hours, any and all premises
     where the Collateral is or may be kept or located.
     
     9.  The occurrence of any of the following events shall
     constitute a Default:
     
               (a)  failure of Debtor, or of any co-maker,
               endorser, surety or guarantor to pay when due any
               amount payable under any of the Secured
               Obligations;
     
               (b)  failure to perform any agreement or covenant
               of Debtor contained herein;
     
               (c)  any statement, representation or warranty of
               Debtor made herein or at any time furnished to the
               Lender is untrue in any respect as of the date
               made;
     
          (d)  entry of any judgment against Debtor in excess of
               $50,000, unless such judgment is by a federal or
               state governmental entity;
     
               (e)  appointment of a receiver due to, loss,
               substantial damage to, destruction, theft, or
               encumbrance to or of any portion of the
               Collateral, or the making of any levy, seizure, or
               attachment thereof;
     
               (f)  Debtor becomes insolvent or unable to pay his
               debts as they mature, or makes an assignment for
               the benefit of his Creditors or any proceeding is
               commenced by or against Debtor alleging that he is
               insolvent or unable to pay his debts as they
               mature:
     
               (g)  death of any Debtor who is a natural person
               or of any partner of any Debtor which is a
               partnership;
     
               (h)  dissolution, consolidation, or merger, or
               transfer of a substantial part of the property of
               any Debtor which is a partnership;
     
          (i)  such a material change in the condition or affairs
               (financial or otherwise) of Debtor or any
               co-maker, endorser, surety or guarantor of any of
     the Secured Obligations as in the opinion of the
               Lender impairs the Lender's security or increases
     his risks; or
     
     10.  Whenever a Default shall exist, the Lender may, at its
     option and without demand or notice, declare all or any part
     of the Secured Obligations immediately due and payable, and
     the Lender may exercise, in addition to the rights and
     remedies granted hereby, all rights and remedies of a
     secured party under the Uniform Commercial Code or any other
     applicable law.
     
     11.  Debtor agrees, in the event of Default, to make the
     Collateral available to the Lender at a place or places
     acceptable to the Lender, and to pay all costs of the Lender
     in the collection of any of the Secured Obligations and the
     enforcement of any of the Lender's rights.  If any
     notification of intended disposition of any of the
     Collateral is required by law, such notification shall be
     deemed reasonably and properly given if mailed at least ten
     (10) days before such disposition, postage prepaid,
     addressed to the Debtor at the address shown below.
     
     12.  No delay or failure by the Lender in the exercise of
     any right or remedy shall constitute a waiver thereof, and
     no single or partial exercise by the Lender of any right or
     remedy shall preclude other or further exercise thereof or
     the exercise of any other right or remedy.
     
     13.  If more than one party shall sign this Agreement, the
     term "Debtor" shall mean all such parties, and each of them
     and all such parties shall be jointly and severally
     obligated hereunder.
     
     14.  All parties agree the terms of the within instrument
     shall be construed according to the laws of the state of
     South Dakota and all actions or proceedings brought
     hereunder shall be heard in a court of competent
     jurisdiction within the state of South Dakota .
     
     
     Executed and delivered at Blaine, Minnesota,
     this 28th day of May, 1996.
     
     
     
     ADDRESS:                      APA OPTICS, INC.
     2950 North East 84th Lane
     Blaine, MN  55449
                                   BY: /s/ Anil K. Jain
      (Seal)                       ITS: President
     
     
     _________________________________________________________
     
     NOTE: Corporate applicants must execute Security Agreement,
     in corporate name, by duly authorized officer, and seal must
     be affixed and duly witnessed; partnership applicants must
     execute Security Agreement in firm name, together with
     signature of an authorized general partner.