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                                                                   EXHIBIT 10.15

                             TAX SHARING AGREEMENT

  This Tax Sharing Agreement ("Agreement") is effective as of the 1st day of
November  1996, by and among GUARDIAN INDUSTRIES CORP., a Delaware corporation
(hereinafter referred to as the "Parent Company"), and OIS OPTICAL IMAGING
SYSTEMS, INC. a Delaware corporation (hereinafter referred to as the
"Subsidiary" or "OIS").

  The term "Parent Company" shall include Guardian Industries Corp. and any
subsidiary thereof whose stock is owned directly or indirectly by Guardian
Industries Corp. and which qualifies as a member of the Parent Company's
affiliated group as defined in Section 1504(a) of the Internal Revenue Code of
1986, as amended ("Internal Revenue Code") and such term shall exclude OIS (and
its subsidiaries).  The terms "Subsidiary" and "OIS" shall include OIS Optical
Imaging Systems, Inc. and any of its subsidiaries acquired or formed after the
effective date of this Agreement, and which later qualify as members of the
Parent Company's affiliated group as defined in Section 1504(a) of the Internal
Revenue Code.

                                   WITNESSETH
  WHEREAS, the Parent Company and Subsidiary are expected to qualify as members
of an affiliated group as defined in Section 1504 (a) of the Internal Revenue
Code ("Affiliated Group"), commencing on November 1, 1996.

  WHEREAS, the Parent Company and Subsidiary desire to file a United States
consolidated income tax return as an Affiliated Group for the taxable period
which includes November 1, 1996 through December 31, 1996 and to file, if
qualified to do so as an Affiliated Group, United States consolidated income
tax returns for subsequent tax years (or other taxable periods).

  WHEREAS, it is the intent and desire of the Parent Company and Subsidiary
that a method be established for each tax year (or other taxable period) that a
United States consolidated income tax return is filed by the Affiliated Group
for sharing and allocating the United States consolidated income tax liability
of the Affiliated Group among its members, for reimbursing the Parent Company
for payment of such tax liability, if any, and for providing for the allocation
of any United States income tax refund arising from a carryback of losses or
tax credits from subsequent tax years (or other taxable periods).

  WHEREAS, the Parent Company and Subsidiary will make available any current
and net operating losses and tax credits as they may have available to reduce
the United States consolidated income tax liability of the Affiliated Group.

  WHEREAS, The Parent Company and Subsidiary desire to provide for the
reimbursement to the Parent Company and/or Subsidiary whose current and net
operating losses and tax credits have been used to reduce the United States
consolidated income tax liability of the Affiliated Group.





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  NOW THEREFORE, In consideration of the mutual covenants and promises
contained in this Agreement, the parties hereto do hereby agree as follows:

A. CONSOLIDATED FEDERAL INCOME TAX RETURNS

  (l)  A United States consolidated income tax return shall be filed by the
Parent Company for the taxable year ending December 31, 1996 and for each
subsequent taxable period during which this Agreement is in effect and for
which the Affiliated Group is required or permitted to file a United States
consolidated income tax return.

  (2)  For each tax year (or other taxable period) the aggregate United States
consolidated income tax liability for members of the Affiliated Group shall be
computed twice, once with the inclusion of the Subsidiary in such computation
and secondly with the exclusion of the Subsidiary from such computation.

  (3)  To the extent that members (including the Parent Company and Subsidiary)
of the Affiliated Group have had their United States income tax liabilities, as
computed on an aggregate basis, increased by inclusion of Subsidiary, an
account payable (liability) of the Subsidiary ("Tax Liability to Parent") to
the Parent Company shall be established on the books of the Parent Company and
of the Subsidiary.  To the extent that members (including the Parent Company
and Subsidiary) of the Affiliated Group have had their United States income tax
liabilities, as computed on an aggregate basis, decreased by inclusion of
Subsidiary, an account payable (liability) of the Parent Company ("Tax
Liability to Subsidiary") to the Subsidiary shall be established on the books
of the Parent Company and of the Subsidiary.  In determining whether the tax
liability of the Affiliated Group has been reduced by the Subsidiary's
deductions or credits it will be assumed that the Affiliated Group first
utilizes comparable credits and net operating loss carryovers from prior years
generated by other members of the Affiliated Group.

  (4)  An estimate of the Tax Liability to Parent or Tax Liability to
Subsidiary shall be made by the Parent Company not later than March 15th for
the preceding calendar year (or taxable period ending on December 31st).  The
resulting estimated account payable shall be collected within thirty (30) days
of the date that such estimate is made.  A final calculation of the Tax
Liability to Parent or Tax Liability to Subsidiary shall be made within 30 days
of the date that the Parent Company files the consolidated return for any
calendar year (or taxable period ending on December 31st).  The resulting final
account payable shall be collected within 30 days of the date that such final
calculation of the Tax Liability to Parent or Tax Liability to Subsidiary is
provided by the Parent Company to Subsidiary.

  (5)  The Parent Company will determine the allocation of the United States
consolidated income tax liability, and the account payables and receivables to
be reflected on the books of the Parent Company and Subsidiary in accordance
with this Agreement.  To the extent that the Subsidiary disagrees with such
determination, the matter shall be referred to the independent certified public
accountants then auditing the books of the Parent Company, whose determination





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shall be final.

  (6)  Payment of the actual United States consolidated income tax liability
for a taxable year (or other taxable period) shall include the payment of
estimated income tax installments due for such tax year (or other taxable
period), which payments, if any, will be determined by the Parent Company based
on an estimate of income tax liability for the tax year (or other taxable
period).  The Subsidiary shall pay to the Parent Company, the Subsidiary's
share of each payment of the actual estimated consolidated income tax
liability, within thirty (30) days of receiving notice of such payment from the
Parent Company.  The Subsidiary's share of any overpayment of estimated income
tax will be refunded to the Subsidiary by the Parent Company within thirty (30)
days after it is determined that the Subsidiary has overpaid the estimated
income tax.

  (7)  If the United States consolidated income tax liability is adjusted for
any tax year (or other taxable period), whether by means of an amended tax
return, claim for refund or after a tax audit by the United States Internal
Revenue Service, the Tax Liability to Parent or Tax Liability to Subsidiary for
that year (or other taxable period) shall be recomputed to give effect to such
adjustments.  The resulting change in the Tax Liability to Parent or Tax
Liability to Subsidiary, shall be determined in the same manner as in Paragraph
A (2) of this Agreement.  In the case of an increase in Tax Liability to Parent
(or decrease in Tax Liability to Subsidiary), the Subsidiary shall pay the
resultant difference to the Parent Company within thirty (30) days after
receiving notice of such liability from the Parent Company.  In the case of a
decrease in Tax Liability to Parent (or increase in Tax Liability to
Subsidiary), the Parent Company shall pay the resultant difference to
Subsidiary within thirty (30) days after the adjustment has been finally
determined.  Any interest (income or expense) and penalties arising from
adjustments to the United States consolidated income tax liability shall be
equitably apportioned between the Parent Company and Subsidiary.

B. PARENT AS AGENT AND CONSENTS

  (1)  The Subsidiary irrevocably designates the Parent Company as its agent
for the purpose of taking any and all action necessary or incidental to the
filing of United States consolidated income tax returns and state combined or
consolidated returns (including, but not limited to, the conduct of any audit
by any taxing authority).

  (2)  The Subsidiary agrees to furnish the Parent Company with any and all
information requested by the Parent Company to carry out the provisions of this
Agreement, to cooperate with Parent Company in filing any return or consent
contemplated by this Agreement and to cooperate in connection with any refund
claim, audit, judicial or other like or similar proceeding.

  (3)  At the direction of the Parent Company, the Subsidiary shall execute and
file such consents, elections, and other documents that may be required or
appropriate for the proper filing of each United States consolidated income tax
return and state combined or consolidated returns.

  (4)  Subsidiary hereby consents to all elections made by the Parent Company on
behalf





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of the Affiliated Group.

C. CONSOLIDATED AND COMBINED STATE INCOME TAX RETURNS

   If the Affiliated Group or any members thereof is required or elects to file
combined or consolidated state or local tax returns including the Subsidiary,
the Parent Company shall not be required to reimburse the Subsidiary for any of
the Subsidiary's tax losses or attributes which are utilized by the Affiliated
Group or any members thereof.  In the event that the Subsidiary would have a
stand alone income, franchise or similar tax liability for state and local
taxes, then Parent Company shall make an allocation of such state or local tax
liability to Subsidiary consistent with the principles set forth in Paragraph A
(2) of this Agreement.

D. SUBSIDIARY LEAVING THE AFFILIATED GROUP

   (1)  If the Subsidiary (or a subsidiary of the Subsidiary) is no longer a
member of the Affiliated Group (a "Former Member"), the Parent Company shall,
upon the request of a Former Member, provide any assistance that shall be
reasonably required to enable the Former Member to pursue any tax refund,
including but not limited to the filing of tax refund claims on behalf of the
Former Member.

   (2)  The Former Member shall be able to participate, in good faith and at its
own expense, in the audit of the portion of the United States consolidated
income tax return of the Affiliated Group which relates to its separate taxable
income or loss and shall be able to participate, in good faith and at its own
expense, in any contest, litigation, or settlement of any issue relating to
such separate taxable income or loss.

   (3)  The Former Member and the remaining members of the Affiliated Group will
fully cooperate with each other in connection with the allocation of income and
expense for the taxable year in which the Former Member leaves the Affiliated
Group.

   (4)  The Former Member (and, in the event the Affiliated Group ceases to file
a United States consolidated return, the Parent Company) shall be bound by the
terms of this Agreement with respect to all tax years during which such Former
Member joined in the filing of United States consolidated income tax returns
and state combined or consolidated returns.

   (5)  The Former Member and the remaining members of the Affiliated Group will
cooperate and provide such information as will be necessary to enable each of
them to file whatever returns are required for United States income tax
purposes and state combined or consolidated returns, or in connection with any
audit or litigation with respect to such returns.

E. MISCELLANEOUS PROVISIONS

   (1)  This Agreement shall apply to the taxable year ending December 31, 1996
and all





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subsequent taxable periods unless the Parent Company and Subsidiary agree to
terminate or modify this Agreement.  Any termination or modification, no matter
when agreed to, shall be deemed effective as of the end of the then current
taxable period.  Notwithstanding termination, this Agreement shall continue in
effect with respect to any payment or refund (Tax Liability to Parent or Tax
Liability to Subsidiary) due for all taxable periods prior to termination.

  (2)  All notices under this Agreement shall be in writing and shall be deemed
to have been sufficiently given or served and effective for all purposes when
presented personally, or sent by facsimile transmission (if receipt of the
transmission is confirmed in writing by the addressee) or three days after
being deposited in a United States postal receptacle for registered or
certified mail addressed, return receipt requested, postage prepaid, to any
person at the address set forth below, or at such other address as such party
shall subsequently designate in writing delivered in the form of a notice to:

  If to Parent Company:   Guardian Industries Corp.
                          Vice President and Tax Counsel
                          2300 Harmon Road
                          Auburn Hills, Michigan 48326

  If to Subsidiary:       OIS Optical Imaging Systems, Inc.
                          Chief Financial Officer
                          47050 Five Mile Road
                          Northville, Michigan 48167

  (3)  Neither this Agreement nor any provision hereof may be changed, waived,
discharged, or terminated orally but only by an instrument in writing signed by
the party against whom enforcement of the change, waiver, discharge, or
termination is sought.

  (4)  This Agreement shall constitute the entire agreement between the parties
concerning the subject matter hereof and shall supersede any prior agreements
and understandings between or among the parties with respect to the subject
matter hereof.

  (5)  The validity, interpretation, and enforceability of this Agreement shall
be governed in all respects by the laws of the State of Michigan.

  (6)  Failure of any party at any time to require the other party's
performance of any obligation under this Agreement shall not affect the right
to require performance of that obligation.  Any waiver by any party of any
breach of any provision of this Agreement shall not be construed as a waiver or
modification of the provision itself, or a waiver of any rights under this
Agreement.

  (7)  Every provision of this Agreement is intended to be severable.  If any
term or provision is illegal or invalid for any reason whatsoever, such
illegality or invalidity shall not affect the validity of the remainder of this
Agreement.





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  (8)  This Agreement may be executed in multiple counterparts each of which
shall be deemed an original and all of which shall constitute one agreement,
and the signatures of any party to any counterpart shall be deemed to be a
signature to, and may be appended to, any other counterpart.

  (9)  This Agreement shall be binding upon and inure to the benefit of any
successor, whether by statutory merger, acquisition of assets or otherwise, to
any of the parties hereto, to the same extent as if the successor had been an
original party to this Agreement.

  (10)   If during a United States consolidated income tax return period
Subsidiary acquires or organizes another corporation or company that is allowed
to be included in the consolidated return of the Affiliated Group, then such
corporation or company shall join in and be bound by this Agreement.

  IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be
executed by their duly authorized representatives as of the date first above
written.
 
                                        GUARDIAN INDUSTRIES CORP.


                                        By      / Jeffrey A. Knight /  
                                           ------------------------------------
                                                  Jeffrey A. Knight
                                                  Group Vice President/Finance


                                        OIS OPTICAL IMAGING SYSTEMS, INC.


                                        By     / Charles C. Wilson /  
                                           ------------------------------------
                                                 Charles C. Wilson
                                                 Executive Vice-President and
                                                 Chief Financial Officer





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