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                                                                      EXHIBIT 3a

                          CERTIFICATE OF INCORPORATION

                                       OF

                         INDUSTRIAL IMAGING CORPORATION

                                      *****

1.  The name of the corporation is Industrial Imaging Corporation.

2.  The address of its registered office in the State of Delaware is 1209 Orange
Street, in the City of Wilmington, County of New Castle. The name of its
registered agent at such address is The Corporation Trust Company.

3.  The nature of the business or purposes to be conducted or promoted is:

    To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

4.  The total number of shares of stock which the Corporation shall have
authority to issue is Twenty-one Million (21,000,000) shares; of which twenty
million (20,000,000) will be Common Stock, of the par value $.01 per share; and
one million (1,000,000) will be Preferred Stock, of the par value $.01 per
share, amounting in the aggregate to Two Hundred Ten Thousand and 00/100 Dollars
($210,000.00).

    Additional designations and powers, preferences and rights and
qualifications, limitations or restrictions thereof of the shares of each class
shall be determined by the Board of Directors of the Corporation from time to
time.

5.  The name and mailing  address of the  Corporation's  incorporator is Juan J.
Amodei, Ph.D.,  Industrial Imaging Corporation,  One Lowell Research Center, 847
Rogers Street, Lowell, Massachusetts 01852.

6.  The name and address of the person who is to serve as the sole director of
the Corporation until the first annual meeting of the stockholders or until his
successors are elected and qualified is:

                              Juan J. Amodei, Ph.D.
                         Industrial Imaging Corporation
                           One Lowell Research Center
                                847 Rogers Street
                           Lowell, Massachusetts 01852

7.  The Corporation is to have perpetual existence.

8.  In furtherance and not in limitation of the powers conferred by statute, the
Board of Directors is expressly authorized:




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     To make, alter or repeal the bylaws of the Corporation.

     To authorize and cause to be executed mortgages and liens upon the real and
personal property of the Corporation.

     To set apart out of any of the funds of the Corporation available for
dividends a reserve or reserves for any proper purpose and to abolish any such
reserve in the manner in which it was created.

     By a majority of the whole Board, to designate one or more committees, each
committee to consist of one or more of the Directors of the Corporation. The
Board may designate one or more directors as alternate members of any committee,
who may replace any absent or disqualified member at any meeting of the
committee. The bylaws may provide that in the absence or disqualification of a
member of a committee, the member or members thereof present at any meeting and
not disqualified from voting, whether or not he or they constitute a quorum, may
unanimously appoint another member of the Board of Directors to act at the
meeting in the place of any such agent or disqualified member. Any such
committee, to the extent provided in the resolution of the Board of Directors,
or in the bylaws of the Corporation, shall have and may exercise all the powers
and authority of the Board of Directors in the management of the business and
affairs of the Corporation, and may authorize the seal of the Corporation to be
affixed to all papers which may require it; but no such committee shall have the
power or authority in reference to amending the Certificate of Incorporation,
adopting an agreement of merger or consolidation, recommending to the
stockholders the sale, lease, or exchange of all or substantially all of the
Corporation's property and assets, recommending to the stockholders a
dissolution of the Corporation or a revocation of a dissolution, or amending the
bylaws of the Corporation; and, unless the resolution or bylaws expressly so
provide, no such committee shall have the power or authority to declare a
dividend or to authorize the issuance of stock.

     When and as authorized by the stockholders in accordance with statute, to
sell, lease or exchange all or substantially all of the property and assets of
the Corporation, including its goodwill and its corporate franchises, upon such
terms and conditions and for such consideration, which may consist in whole or
in part of money or property, including shares of stock in, and/or other
securities of, any other corporation or corporations, as its board of directors
shall deem expedient and for the best interests of the Corporation.

9.   To the maximum extent permitted by Section 102(b)(7) of the General
Corporation Law of Delaware, a director of this Corporation shall not be
personally liable to the Corporation or its stockholders for monetary damages
for breach of fiduciary duty as a director, except for liability (i) for any
breach of the director's duty of loyalty to the Corporation or its stockholders,
(ii) for acts or omissions not in good faith or which involve intentional
misconduct or a knowing violation of law, (iii) under Section 174 of the
Delaware General Corporation Law, or (iv) for any transaction from which the
director derived an improper personal benefit.

10.  Whenever a compromise or arrangement is proposed  between this  Corporation
and its

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creditors or any class of them and/or between this Corporation and its
stockholders or any class of them, any court or equitable jurisdiction within
the State of Delaware may, on the application in a summary way of this
Corporation or of any creditor or stockholder thereof, or on the application of
any receiver or receivers appointed for this Corporation under the provisions of
Section 291 of Title 8 of the Delaware Code or on the application of trustees in
dissolution or of any receiver or receivers appointed for this Corporation under
the provisions of Section 279 of Title 8 of the Delaware Code, order a meeting
of the creditors or class of creditors, and/or of the stockholders or class of
stockholders of this Corporation, as the case may be, to be summoned in such
manner as the said court directs. If a majority in number representing
three-fourths in value of the creditors or class of creditors, and/or of the
stockholders or class of stockholders of this Corporation, as the case may be,
agree to any compromise or arrangement to any reorganization of this Corporation
as consequences of such compromise or arrangement, the said compromise or
arrangement and the said reorganization shall, if sanctioned by the court to
which the said application has been made, be binding on all the creditors or
class of creditors, and/or on all the stockholders or class of stockholders of
this Corporation, as the case may be, and also on this Corporation.

11.  Meetings of the stockholders may be held within or without the State of
Delaware, as the bylaws may provide. The books of the Corporation may be kept
(subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
Board of Directors or in the bylaws of the Corporation. Elections of directors
need not be by written ballot unless the bylaws of the Corporation shall so
provide.

12.  The Corporation reserves the right to amend, alter, change, or repeal any
provision contained in this certificate of incorporation, in the manner now or
hereafter prescribed by statute, and all rights conferred upon stockholders
herein are granted subject to this reservation.


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    THE UNDERSIGNED, being the incorporator named hereinbefore, for the purposes
of forming a corporation pursuant to the General Corporation Law of the State of
Delaware, does make this certificate, hereby declaring and certifying that this
is his act and deed and the facts herein stated are true, and accordingly, has
hereunto set his hand this day of           ,    1996.



                                         --------------------------
                                         Juan J. Amodei, Ph.D.






COMMONWEALTH OF MASSACHUSETTS               )
                                            ) ss.:
COUNTY OF MIDDLESEX                         )

    BE IT REMEMBERED that on this day of , 1996, personally came before me, a
Notary Public for the Commonwealth of Massachusetts, Juan J. Amodei, Ph.D., the
party to the foregoing Certificate of Incorporation, known to me personally to
be such, and acknowledged the said Certificate to be his free act and deed and
that the facts stated therein are true.

    GIVEN under my hand and seal of office the day and year aforesaid.



                                         --------------------------
                                         Notary Public
                                         My commission expires:


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