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                                 THIRD AMENDMENT TO
                                  CREDIT AGREEMENT

          This Amendment is agreed to as of the 27th day of February, 1998, by
and among BMC Industries, Inc., a Minnesota corporation (the "Borrower");
Norwest Bank Minnesota, National Association, a national banking association, as
Agent under the Credit Agreement described below (in such capacity, the
"Agent"); and Norwest Bank Minnesota, National Association, a national banking
association, U.S. Bank National Association, a national banking association
formerly known as First Bank National Association, and NBD Bank, a Michigan
banking corporation, as Banks under the Credit Agreement (the "Banks").

          The Borrower, the Agent and the Banks are each parties to a Credit
Agreement dated as of June 5, 1996, as amended by amendments dated June 27, 1997
and December 23, 1997 (together with all amendments, modifications and
restatements thereof, the "Credit Agreement").

          The Borrower has asked for changes in its ability to make general
purpose borrowings under the Credit Agreement, and the Agent and the Banks are
willing to grant the Borrower's request.

          ACCORDINGLY, in consideration of the mutual covenants contained in the
Credit Agreement and herein, the parties hereby agree as follows:

          1.   AMENDMENT.  The next-to-last sentence of Section 2.2 of the
Credit Agreement (commencing with the words, "In addition, the Borrower may
use . . .") is hereby deleted, and the following is substituted therefor:

          In addition, the Borrower may use the proceeds of one or more
          Borrowings under this Section 2.2 (each, a "General Purpose Facility B
          Borrowing") for the Borrower's general corporate purposes so long as
          the aggregate principal amount of such General Purpose Facility B
          Borrowings outstanding at any one time does not exceed $20,000,000.

          2.   REPRESENTATIONS AND WARRANTIES.  The Borrower hereby represents
and warrants to the Agent and the Banks as follows:

          (a)  The Borrower has all requisite power and authority, corporate or
     otherwise, to execute and deliver this Amendment, and to perform this
     Amendment and the Credit Agreement as amended hereby.  This Amendment has
     been duly and validly executed and delivered to the Agent by the Borrower,
     and this Amendment, and the Credit Agreement as amended hereby, constitute
     the Borrower's legal, valid and binding obligations enforceable in
     accordance with their terms.

          (b)  The execution, delivery and performance by the Borrower of this
     Amendment, and the performance of the Credit Agreement as amended hereby,
     have

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     been duly authorized by all necessary corporate action and do not and
     will not (i) require any authorization, consent or approval by any
     governmental department, commission, board, bureau, agency or
     instrumentality, domestic or foreign, (ii) violate the Borrower's articles
     of incorporation or bylaws or any provision of any law, rule, regulation or
     order presently in effect having applicability to the Borrower, or
     (iii) result in a breach of or constitute a default under any indenture or
     agreement to which the Borrower is a party or by which the Borrower or its
     properties may be bound or affected.

          (c)  All of the representations and warranties contained in Article IV
     of the Credit Agreement are correct on and as of the date hereof as though
     made on and as of such date, except to the extent that such representations
     and warranties relate solely to an earlier date.

          3.   CONDITIONS.  The amendments set forth in paragraph 1 shall be
effective only if the Agent has received this Amendment, duly executed by each
of the parties hereto, on or before the date hereof (or such later date as the
Banks may agree to in writing).

          4.   MISCELLANEOUS.  The Borrower shall pay all costs and expenses of
the Agent, including attorneys' fees, incurred in connection with the drafting
and preparation of this Amendment and any related documents.  Except as amended
by this Amendment, all of the terms and conditions of the Credit Agreement shall
remain in full force and effect.  This Amendment may be executed in any number
of counterparts, each of which when so executed and delivered shall be deemed to
be an original and all of which counterparts of this Amendment, taken together,
shall constitute but one and the same instrument.  This Amendment shall be
governed by the substantive law of the State of Minnesota.

          IN WITNESS WHEREOF, the parties hereto have caused this  Amendment to
be executed as of the date first above written.

BMC INDUSTRIES, INC.                         NORWEST BANK MINNESOTA,
                                                  NATIONAL ASSOCIATION, AS
                                                  AGENT AND AS A BANK



By /s/JEFFREY HATTARA                        By /s/SCOTT BJELDE
   ------------------                           ---------------
     Its VP Administration & Finance              Its Vice President
     & CFO


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U.S. BANK NATIONAL                           NBD BANK
     ASSOCIATION

By ________________________________

     Its ______________________________      By /s/MARGUERITE C. GORDY
                                                  Its _Second Vice President

                                 CONSENT OF GUARANTOR

          The undersigned, as a guarantor of all indebtedness of the Borrower to
the Banks under its Guaranty dated June 5, 1996, hereby consents to the
foregoing Amendment and acknowledges that all indebtedness arising under the
Credit Agreement, as amended thereby, shall constitute Indebtedness as defined
in and guarantied under that Guaranty. The foregoing confirmation shall not be
deemed to limit the terms of the Guaranty in any manner.  The undersigned
acknowledges that this Consent merely confirms the terms of the Guaranty, and
that no such confirmation is required in connection with this Amendment or any
future amendment to or restatement of the Credit Agreement or any document
executed in connection with the Credit Agreement or this Amendment.

                                             VISION-EASE LENS, INC.

                                             By /s/Ray Rogers

                                                Its Director___________________