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                      BMC INDUSTRIES, INC. PROFIT SHARING PLAN
                                   1994 REVISION


                           THIRD DECLARATION OF AMENDMENT

Pursuant to the retained power of amendment contained in Section 11.2 of the
instrument entitled "BMC Industries, Inc. Profit Sharing Plan -- 1994 Revision,"
the undersigned hereby amends said instrument in the following manner:

1.   Subsection 7.2(A) thereof is amended by substituting "$5000" for "$3500."

2.   Subsection 8.1(A)(1) thereof is amended by substituting "$5000" for "$3500"
     each place it appears therein.

3.   Section 12.27 thereof is amended to read as follows:

     "12.27  QUALIFIED EMPLOYEE.  A "Qualified Employee" is an Employee who
     performs services for a Participating Business Unit as a common-law
     employee (as classified by the Participating Employer at the time the
     services are performed without regard to any subsequent
     reclassification) together with any Employee who is a United States
     citizen and who performs services for a foreign subsidiary of a
     Participating Employer as a common-law employee of the foreign
     subsidiary (as classified by the Participating Employer at the time the
     services are performed without regard to any subsequent
     reclassification), with respect to which subsidiary such Participating
     Employer has entered into an agreement under Code section 3121(1), but
     only if contributions under a funded plan of deferred compensation,
     which is sponsored by such foreign subsidiary or a Participating
     Employer, are not provided for such person with respect to remuneration
     paid to him by such foreign subsidiary, provided that such person is
     employed at a facility, or within a division or business unit, the
     eligible employees of which have been designated by the Participating
     Employer to participate in the Plan.  In no event, however, will the
     term Qualified Employee include any individual who is

          (a)  covered by a collective bargaining agreement, for whom retirement
     benefits were the subject of good faith bargaining between such person's
     representative and the Participating Employer, and who is not, as a result
     of such bargaining, specifically covered by this Plan; or

          (b)  a nonresident alien who receives no earned income (within the
     meaning of Code section 911(d)(2)) from a Participating Employer that
     constitutes income from sources within the United States (within the
     meaning of Code section 861(a)(3)); or

          (c)  a leased employee as defined under Code section 414(n)(2)."
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The amendments set forth are items 1 and 2 above are effective January 1, 1998,
and apply to all Participants, including those who terminated employment before
January 1, 1998, and the Beneficiaries of deceased Participants, including those
who died before January 1, 1998.  The amendment set forth at item 3 above is
effective March 1, 1998.

IN WITNESS WHEREOF, the undersigned has caused this instrument to be executed by
its duly authorized officers this 28th day of February, 1998.

                                   BMC INDUSTRIES, INC.




Attest:  /s/JON A. DOBSON          By: /s/STEFAN PETERSON
         ----------------------        ---------------------
         Secretary                    Director of Compensation, Benefits & HRIS

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