<PAGE>
                                          
                         SECOND AMENDMENT TO CREDIT AGREEMENT

          This Second Amendment to Credit Agreement (the "SECOND AMENDMENT")
dated as of December 30, 1998 is by and among BMC Industries Inc., a Minnesota
corporation (the "BORROWER"), Bankers Trust Company, a New York banking
corporation, as administrative agent for the Lenders hereunder (in such capacity
individually, the "AGENT") and as a Lender, NBD Bank as documentation agent and
as a Lender and the several banks and other financial institutions from time to
time party to the Credit Agreement described below (the "LENDERS").

                                   R E C I T A L S:

          WHEREAS, the Borrower, the Agents and the Lenders are parties to an
Amended and Restated Credit Agreement dated as of June 25, 1998 (as hereafter
amended, restated, supplemented or otherwise modified, the "CREDIT AGREEMENT"),
pursuant to which the Lenders have made and may hereafter make loans, advances
and other extensions of credit to the Borrower;

          WHEREAS, under SECTION 7.11 of the Credit Agreement the Borrower by
December 31, 1998 affirmatively agreed to refinance, amend or otherwise modify
that certain Credit Offer Letter between Buckbee-Mears Europe GmbH and Deutsche
Bank AG (Stuttgart) dated September 30, 1994 such that the facility became an
unsecured facility and Agent received such related releases of security
interests and Liens;

          WHEREAS, such refinancing, amendment or modification of such facility
will not have occurred as of December 31, 1998;

          WHEREAS, the Borrower has requested that the Agents and the Lenders
amend SECTION 7.11 of the Credit Agreement as set forth herein and the Lenders
and the Agents are agreeable to the same, subject to the terms and conditions
hereof;

          WHEREAS, this Second Amendment shall constitute a Loan Document and
these Recitals shall be construed as part of this Second Amendment;

          NOW, THEREFORE, in consideration of the foregoing and the agreements,
promises and covenants set forth below, and for other good and valuable
consideration the receipt and sufficiency of which are hereby acknowledged, the
parties hereto agree as follows:

          1.   DEFINITIONS.  Capitalized terms used but not otherwise defined in
this Second Amendment shall have the meanings ascribed to them in the Credit
Agreement.

          2.   AMENDMENT TO THE CREDIT AGREEMENT.  Subject to the conditions of
this Second Amendment, SECTION 7.11 of the Credit Agreement is hereby amended by
deleting the text "December 31, 1998" therein and inserting in lieu thereof the
text "April 30, 1999".


<PAGE>


          3.   CONDITIONS PRECEDENT.  Notwithstanding any other provision
contained in this  Second Amendment or any other document, the effectiveness of
this Second Amendment is expressly conditioned upon the satisfaction of each
matter set forth in this SECTION 4, all in form and substance acceptable to the
Agent in its sole and absolute discretion:

          (a)  SECOND AMENDMENT.  The Agent shall have received a duly executed
copy of this Second Amendment signed by the Borrower, the Agent and the Required
Lenders.

          (b)  WARRANTIES AND REPRESENTATIONS.  All of the warranties and
representations of the Borrower contained in the Credit Agreement and in the
other Loan Documents (including, without limitation, in this Second Amendment)
shall be true and correct in all material respects on and as of the date first
written above (except those representations and warranties made expressly as of
a different date). The Borrower hereby represents and warrants that the
execution, delivery and performance of this Second Amendment and the
consummation of the transactions contemplated hereby have been duly authorized
by all necessary corporate action and this Second Amendment is a legal, valid
and binding obligation of the Borrower enforceable against the Borrower in
accordance with its terms, except as the enforcement thereof may be subject to
(i) the effect of any applicable bankruptcy, insolvency, reorganization,
moratorium, or similar laws affecting creditors' rights generally and (ii)
general principles of equity (regardless of whether such enforcement is sought
in a proceeding in equity or at law).  In furtherance of the foregoing, the
Borrower hereby represents and warrants that as of the date first written above
each of the conditions precedent contained in this SECTION 4 has been fully
satisfied in accordance with the express terms thereof.

          (c)  NO EVENT OF DEFAULT.  Except as expressly waived herein, no Event
of Default shall have occurred and be continuing as of the date first written
above, or, will occur after giving effect to this Second Amendment in accordance
with its terms.

          (d)  NO LITIGATION.  No litigation, investigation, proceeding,
injunction, restraint or other action shall be pending or threatened against the
Borrower or any Affiliate of the Borrower, or any officer, director, or
executive of any thereof, which restrains, prevents or imposes adverse
conditions upon, or which otherwise relates to, the execution, delivery or
performance of this Second Amendment.

          4.   FURTHER ASSURANCES. The Borrower hereby agrees, at its expense,
to duly execute, acknowledge and deliver to the Agent all agreements,
certificates, instruments, opinions and other documents, and take all such
actions, as the Agent may reasonably request in order to further effectuate the
purposes of this Second Amendment and to carry out the terms hereof.

          5.   LIMITATION OF SECOND AMENDMENT.  The parties hereto agree and
acknowledge that nothing contained in this Second Amendment in any manner or
respect limits or terminates any of the provisions of the Credit Agreement or
any of the other Loan Documents other than as expressly set forth herein and
further agree and acknowledge that the Credit Agreement (as amended hereby) and
each of the other Loan Documents remain and continue in full force and effect
and are hereby ratified and confirmed.  Except to the extent expressly set forth
herein, the execution, delivery and effectiveness of this Agreement shall not
operate as a waiver of any rights, power or remedy of the Lenders or the Agent
under the Credit Agreement or any other Loan Document, nor 


                                      -2-

<PAGE>


constitute a waiver of any provision of the Credit Agreement or any other 
Loan Document.  No delay on the part of any Lender or the Agent in exercising 
any of their respective rights, remedies, powers and privileges under the 
Credit Agreement or any of the Loan Documents or partial or single exercise 
thereof, shall constitute a waiver thereof.  None of the terms and conditions 
of this Second Amendment may be changed, waived, modified or varied in any 
manner, whatsoever, except in accordance with SECTION 11.1 of the Credit 
Agreement.

          6.   COSTS, EXPENSES AND TAXES.  Pursuant to SECTION 11.4 of the
Credit Agreement, the Borrower agrees to pay on demand all costs and expenses of
the Lenders and the Agent in connection with the preparation, execution and
delivery of this Second Amendment including the reasonable fees and
out-of-pocket expenses of counsel to the Agent with respect thereto.  

          7.   EXECUTION IN COUNTERPARTS.  This Second Amendment may be executed
in any number of counterparts and by different parties hereto in separate
counterparts, each of which when so executed and delivered shall be deemed to be
an original and all of which taken together shall constitute but one and the
same instrument.

          8.   GOVERNING LAW.  THIS SECOND AMENDMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, WITHOUT REGARD
TO THE INTERNAL CONFLICTS OF LAWS PROVISIONS THEREOF. 

          9.   HEADINGS.  Section headings in this Second Amendment are included
herein for convenience of reference only and shall not constitute a part of this
Second Amendment for any other purposes.     
                                      * * * *
                              [Signature pages follow]


                                      -3-

<PAGE>



          IN WITNESS WHEREOF, this Second Amendment has been duly executed as of
the date first written above.  

<TABLE>
<S>                                               <C>
BMC INDUSTRIES INC.                               NORWEST BANK MINNESOTA, 
                                                  NATIONAL ASSOCIATION
                                     
By:     /s/ Jeffrey J. Hattara                    By:    /s/ Scott D. Bjelde   
       ----------------------------                      -------------------------
Name:       Jeffrey J. Hattara                    Name:      Scott D. Bjelde   
Title:  VP Finance & Admn and CFO                 Title:     Vice President    


BANKERS TRUST COMPANY, in its 
individual capacity and as Administrative        HARRIS TRUST AND SAVINGS BANK   
Agent                                       
       
By:    /s/ Robert R. Telesca                     By:    /s/ Catherine C. Ciolek  
       -----------------------------                   --------------------------
Name:      Robert R. Telesca                     Name:      Catherine C. Ciolek  
Title:     Assistant Vice President              Title:     Vice President       


NBD BANK, in its individual capacity and as      WACHOVIA BANK, N.A.      
Documentation Agent                              
       
By:   /s/ Marguerite C. Gordy                    By:  /s/ Todd J. Eagle    
     -------------------------------                  ---------------------------
Name:     Marguerite C. Gordy                    Name:    Todd J. Eagle    
Title:    Vice President                         Title:   Vice President   

                                                 UNION BANK OF CALIFORNIA

                                                 By:  ---------------------------
                                                 Name: --------------------------
                                                 Title: -------------------------

U.S. BANK NATIONAL ASSOCIATION                   CREDIT AGRICOLE INDOSUEZ 
                                                
By:   /s/ David Shapiro                          By:   /s/ Jean Yves Klein  
      ----------------------------                     ----------------------------
Name:     David Shapiro                          Name:     Jean Yves Klein           
Title:  Assistant Vice President                 Title:    General Manager, 
                                                           Chicago Branch 



THE FIRST NATIONAL BANK OF CHICAGO               
                                                 
By:  /s/ Glenn A. Cue                            By:  /s/ W. Leroy Startz            
     -----------------------------                    ----------------------------   
Name:    Glenn A. Cue                            Name:    W. Leroy Startz            
Title:   Vice President                          Title:   First Vice President       
</TABLE>