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                                                                    Exhibit 4.14
                                          
                            AMENDMENT OF LOAN AGREEMENT

     This Amendment of the Loan Agreement ("Amendment") is made as of February
9, 1998, by and between Photran Corporation, a Minnesota corporation (the
"Company"), and Steven King, a Minnesota resident (the "Investor").

                                       RECITALS

     A.   The Company and Investor have entered into that certain Loan Agreement
     dated September 10, 1997 (the "Loan Agreement").

     B.   The Company and the Investor have agreed to amend the Loan Agreement
     as provided in this Amendment.

     NOW, THEREFORE, in consideration of their mutual covenants and agreements
contained herein, and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Company and the Investor agree
to amend the Loan Agreement as follows:

1.   LOAN/PROMISSORY NOTE.  Section 1 shall be amended to read as follows:

          The Investor agrees to make a loan to the Company of One Million One
          Hundred Thousand Dollars ($1,100,000.00) in return for the delivery to
          him of promissory note in the form attached hereto as Exhibit A (the
          "Note"), accompanied by a Security Agreement in the form of Exhibit B
          (the "Security Agreement") with all amendments thereto, securing
          repayment of the Note.  The delivery of the Note shall be made
          concurrently with the execution of this Agreement by the Investor. 
          The unpaid principal balance of the Note shall bear interest from the
          date of each principal amount advanced by the Investor at the rate
          equal to three and one-half percent (3.50%) in excess of the
          "Reference Rate" announced from time to time by First Bank National
          Association, as charged on a daily basis.

2.   WARRANTS EXPIRATION DATE.  Section 2 is amended to read as follows:

          WARRANTS.  In consideration of the $1,100,000.00 loan made hereunder,
          the Company shall issue to the Investor, with delivery of the
          $1,100,000.00 Note, a warrant, in the form attached hereto as Exhibit
          C (the "100,000 A Warrant"), to purchase 100,000 shares of Common
          Stock, at an initial exercise price equal to $4.00 per share, a
          warrant, in the form attached hereto as Exhibit D (the "10,000
          Warrant"), to purchase 10,000 shares of Common Stock, at an initial
          exercise price equal to $4.00 per share. In consideration of
          relinquishment by Investor of 

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          certain rights in the collateral of the Company, the Company shall 
          issue to the Investor, a warrant, in the form of attached Exhibit E 
          (the "100,000 B Warrant"), to purchase 100,000 shares of Common 
          Stock, at an initial exercise price equal to $4.25 per share.  The 
          shares of Common Stock issuable upon exercise of these warrants are 
          referred to hereinafter as the "Warrant Stock."  As additional 
          consideration for the warrants, Investor shall pay to the Company 
          an amount equal to $.03 per share of Warrant Stock 
          contemporaneously with the execution of this Agreement.
          
3.   NOTE.  All references in the Agreement to "Note" shall be deemed to refer
to the "Note" as defined herein.

4.   CONTINUING EFFECT.  Except as amended hereby, the Loan Agreement shall be
and remain in full force and effect.

     IN WITNESS WHEREOF, this Amendment has been executed as of the day and year
first above written.


COMPANY:                      PHOTRAN CORPORATION 


                              By     /s/ Paul T. Fink
                                ---------------------------------
                                  Its President
                                ---------------------------------

                              By
                                ---------------------------------
                                  Its
                                ---------------------------------



INVESTOR                           By /s/ Steven King
                                ---------------------------------
                                       Steven King




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