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                                                                    EXHIBIT 10.2




                                 PROMISSORY NOTE


$500,000                                                     ANN ARBOR, MICHIGAN
                                                            DATED: APRIL 5, 2001


         FOR VALUE RECEIVED, JEFFREY S. WILLIAMS, ("Borrower"), promises to pay
to the order of GENOMIC SOLUTIONS INC., a Delaware corporation ("Lender"), at
4355 Varsity Drive, Suite E, Ann Arbor, Michigan 48108, or at such other place
as Lender may designate in writing, in lawful money of the United States of
America the principal sum of Five Hundred Thousand Dollars ($500,000) plus
interest as hereinafter provided, on or prior to the earlier to occur of (i) two
(2) years from the date of this promissory note (the "Note") and (ii) in the
event of termination of Borrower's employment with Lender other than termination
by Lender without cause, as that term is used in the Employment Agreement
between Genomic Solutions Inc. and Jeffrey S. Williams, dated January 1, 2000 as
amended, the Note and all interest accrued to date shall be immediately due and
payable on the date of termination.

         Interest on the unpaid principal balance of the Note will accrue at a
rate per annum equal to 6.5%. Interest accrued on the principal balance of this
Note shall be paid to Lender in annual installments of interest only, commencing
on April 4, 2002 and continuing thereafter until the entire unpaid principal of
this Note has been paid in full. The entire unpaid principal balance of this
Note, together with all accrued and unpaid interest, shall be immediately due
and payable in full on the Due Date. All accrued interest shall be due and
payable at the time of payment of the principal amount.

         This Note may be paid in full or in part at any time without payment of
any prepayment fee or penalty. All payments received hereunder shall, at the
option of Lender, first be applied against accrued and unpaid interest and the
balance against principal. Borrower expressly assumes all risks of loss or delay
in the delivery of any payments made by mail, and no course of conduct or
dealing shall affect Borrower's assumption of these risks.

         Borrower and Lender have entered into a Stock Pledge Agreement of even
date herewith (the "Pledge Agreement"), pursuant to which Borrower has pledged
and granted Lender a security interest in 500,000 shares of the callable common
stock of the Lender, to secure all of Borrower's obligations to Lender under
this Note.

         The occurrence of any of the following shall constitute an "Event of
Default" under this Note: (i) Borrower fails to make any payment of principal or
interest when due under this Note or fails to perform or comply with, or
defaults with respect to, any of the terms, covenants, or conditions of this
Note; (ii) Borrower becomes insolvent or unable to pay its debts as they become
due or makes an assignment for the benefit of its creditors; (iii) a receiver or
a trustee is appointed for Borrower's assets, and such receiver or trustee is
not discharged within sixty (60) days of such appointment; (iv) a proceeding of
any nature under the federal Bankruptcy Code, as amended, or any state
insolvency statute, is commenced against Borrower or a voluntary proceeding is
instituted by Borrower with the Borrower as debtor, and such proceeding, if
involuntary, is not set aside within sixty (60) days from the date of its
institution; or (v) an Event of Default, as defined in the


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Pledge Agreement, occurs.

         Upon the occurrence of an Event of Default, Lender, at its option and
without notice to Borrower, may declare the entire unpaid principal balance of
this Note and all accrued interest, together with all other indebtedness of
Borrower to Lender, to be immediately due and payable. Neither Lender's failure
promptly to exercise its right to declare the outstanding principal and accrued
unpaid interest hereunder to be immediately due and payable, nor Lender's
failure to demand strict performance of any other obligation of Borrower or any
other person who may be liable hereunder, shall constitute a waiver of any such
rights, nor a waiver of such rights in connection with any future default on the
part of Borrower or any other person who may be liable hereunder. Upon
occurrence of an Event of Default, Borrower shall pay Lender, in addition to all
other sums provided in this Note, all of Lender's costs and expenses, including
reasonable attorneys' fees, incurred by Lender in the collection of all sums
payable under this Note.

         Borrower and all endorsees, sureties and guarantors hereof hereby
jointly and severally waive presentment for payment, demand, notice of
non-payment, notice of protest or protest of this Note, and Lender's diligence
in collection or bringing suit, and do hereby consent to any and all extensions
of time, renewals, waivers or modifications as may be granted by Lender with
respect to payment or any other provisions of this Note. The liability of
Borrower under this Note shall be absolute and unconditional, without regard to
the liability of any other party.

         This Note shall be binding upon Borrower and its successors and
assigns, and the benefits hereof shall inure to Lender and its successors and
assigns. This Note has been executed in the State of Michigan, and all rights
and obligations hereunder shall be governed by the laws of the State of
Michigan.

                                    BORROWER:




                                    By: /s/ Jeffrey S. Williams
                                    --------------------------------------------
                                          Jeffrey S. Williams



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