Registration
                                                                      Number 33-

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM S-8

                             REGISTRATION STATEMENT
                                      under
                           The SECURITIES ACT OF 1933

                               COGNEX CORPORATION
               (Exact name of issuer as specified in its charter)

                            Massachusetts 04-2713778
          State of Incorporation (IRS Employer Identification Number)

                       One Vision Drive, Natick, MA 01760
                    (Address of Principal Executive Offices)

                                 (617) 650-3000
              (Registrant's telephone number, including area code)

                               COGNEX CORPORATION
                    1991 Isys Long Term Equity Incentive Plan
                            (Full title of the Plan)

                        Anthony J. Medaglia, Jr., Esquire
                           Hutchins, Wheeler & Dittmar
                           A Professional Corporation
                               101 Federal Street
                           Boston, Massachusetts 02110
                                 (617) 951-6600
            (Name, address and telephone number of agent for service)

                         CALCULATION OF REGISTRATION FEE

                                   Proposed    Proposed
Title of                           Maximum     Maximum
Securities        Amount           Offering    Aggregate      Amount of
to be             to be            Price       Offering       Registration
Registered        Registered(l)    Per Share   Price          Fee(2)

Common Stock,     253,547 shares   $  .00068   $     172.41   $         .06
par value          60,449 shares    $    .51   $  30,843.75   $       10.64
$.002 per share     7,593 shares     $   .29   $   2,195.67   $         .75
                                   Total       $  33,211.83   $      100.00

(1)   Also registered  hereunder are such additional  number of shares of common
      stock,  presently  indeterminable,  as may be  necessary  to  satisfy  the
      antidilution  provisions of the Plan to which this Registration  Statement
      relates.

(2)   The  registration  fee has been  calculated  with  respect to the  253,547
      shares  registered  on the basis of the price at which  restricted  shares
      issuable under the Plan may be purchased and with respect to the remaining
      68,042 on the basis of the price at which options may be exercised.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT


Item 3.  Incorporation of Documents by Reference

      The Company hereby  incorporates by reference the documents  listed in (a)
through (c) below. In addition,  all documents subsequently filed by the Company
pursuant to Section 13(a), 13(c), 14 and 15(d) of the Securities Exchange Act of
1934 (prior to filing of a  Post-Effective  Amendment  which  indicates that all
securities  offered  have been sold or which  deregisters  all  securities  then
remaining  unsold)  shall be  deemed to be  incorporated  by  reference  in this
Registration  Statement and to be a part thereof from the date of filing of such
documents.

      (a) The Company's  latest  annual  report filed  pursuant to Section 13 or
15(d) of the  Securities  Exchange  Act of 1934 or the latest  Prospectus  filed
pursuant to Rule 424(b) under the Securities Act of 1933,  which contains either
directly or by incorporation by reference,  audited financial statements for the
Company's latest fiscal year for which such statements have been filed.

      (b) All of the reports  filed  pursuant  to Section  13(a) or 15(d) of the
Securities  Exchange Act of 1934 since the end of the fiscal year covered by the
annual report or the Prospectus referred to in (a) above.

      (c) The  description  of the Company's  Common Stock which is contained in
the  Registration  Statement filed by the Company under the Securities  Exchange
Act of 1934, including any amendment or report filed for the purpose of updating
such description.

Item 4.  Description of Securities

      Inapplicable

Item 5.  Interests of Named Experts and Counsel

     The validity of the  authorization and issuance of the Common Stock offered
hereby  will be passed upon for the Company by  Hutchins,  Wheeler & Dittmar,  A
Professional Corporation,  Boston, Massachusetts.  Anthony J. Medaglia, Jr., who
is a stockholder of Hutchins, Wheeler & Dittmar, A Professional Corporation,  is
Clerk of the Company.  Mr.  Medaglia owns 48,602 shares of the Company's  Common
Stock.  In addition Mr. Medaglia holds options for the purchase of 22,400 shares
of the Company's Common Stock.

Item 6.  Indemnification of Directors and Officers

      Section 67 of Chapter  156B of the  General  Laws of the  Commonwealth  of
Massachusetts provides as follows:

      "Section 67. Indemnification of directors,  officers,  employees and other
agents of a  corporation,  and persons  who serve at its  request as  directors,
officers, employees or other agents of another organization, or who serve at its
request in any  capacity  with  respect to any  employee  benefit  plan,  may be
provided by it to whatever extent shall be specified in or authorized by (i) the
articles of organization or (ii) a by-law adopted by the stockholders or (iii) a
vote  adopted by the  holders of a majority  of the shares of stock  entitled to
vote on the election of directors. Except as the articles of






organization  or  by-laws  otherwise  require,  indemnification  of any  persons
referred to in the preceding  sentence who are not directors of the  corporation
may  be  provided  by it  to  the  extent  authorized  by  the  directors.  Such
indemnification  may include payment by the corporation of expenses  incurred in
defending  a civil or  criminal  action or  proceeding  in  advance of the final
disposition of such action or proceeding,  upon receipt of an undertaking by the
person  indemnified  to repay such payment if he shall be  adjudicated to be not
entitled to indemnification under this section which undertaking may be accepted
without reference to the financial ability of such person to make repayment. Any
such indemnification may be provided although the person to be indemnified is no
longer an officer,  director,  employee or agent of the  corporation  or of such
other organization or no longer serves with respect to any such employee benefit
plan.

      No  indemnification  shall be provided  for any person with respect to any
matter as to which he shall have been  adjudicated in any proceeding not to have
acted in good  faith in the  reasonable  belief  that his action was in the best
interest of the corporation or to the extent that such matter relates to service
with  respect  to an  employee  benefit  plan,  in  the  best  interests  of the
participants or beneficiaries of such employee benefit plan.

      The absence of any express provision for  indemnification  shall not limit
any right of indemnification existing independently of this section.

      A  corporation  shall have power to purchase  and  maintain  insurance  on
behalf of any person who is or was a director,  officer, employee or other agent
of the corporation,  or is or was serving at the request of the corporation as a
director,  officer,  employee  or other  agent of another  organization  or with
respect to any employee benefit plan,  against any liability  incurred by him in
any such  capacity,  or arising  out of his  status as such,  whether or not the
corporation would have the power to indemnify him against such liability."

      Article VII of the By-laws of the Company provides as follows:

                                   ARTICLE VII

                     Indemnification of Directors and Others

      Section 7.1   Definitions

      For purposes of this Article VII:

      (a) "Director/officer"  means any person who is serving or has served as a
Director,  officer,  employee or other  agent of the  Corporation  appointed  or
elected by the Board of Directors or the stockholders of the Corporation, or who
is serving  or has  served at the  request  of the  Corporation  as a  Director,
officer,  trustee,  principal,  partner,  employee  or other  agent of any other
organization.

      (b) "Proceeding" means any action, suit or proceeding,  civil or criminal,
brought  or  threatened  in or before  any court,  tribunal,  administrative  or
legislative body or agency.

      (c)  "Expense"  means any fine or penalty,  and any  liability  fixed by a
judgment, order, decree or award in a Proceeding,  any amount reasonably paid in
settlement of a Proceeding  and any  professional  fees and other  disbursements
reasonably incurred in connection with a Proceeding.







      Section 7.2   Right to Indemnification

      Except as limited by law or as provided  in  Sections  7.3 and 7.4 of this
Article VII, each Director/officer (and his heirs and personal  representatives)
shall be indemnified by the Corporation  against any Expense  incurred by him in
connection  with  each  Proceeding  in which he is  involved  as a result of his
serving or having served as a Director/officer.

      Section 7.3   Indemnification not Available

      No indemnification shall be provided to a Director/officer with respect to
a Proceeding as to which it shall have been  adjudicated  that he did not act in
good faith in the reasonable belief that his action was in the best interests of
the Corporation.

      Section 7.4   Compromise or Settlement

      In the event that a Proceeding is  compromised  or settled so as to impose
any liability or obligation on a  Director/officer  or upon the Corporation,  no
indemnification  shall be provided as to said  Director/officer  with respect to
such Proceeding if such Director/officer shall have been adjudicated not to have
acted in good  faith in the  reasonable  belief  that his action was in the best
interests of the Corporation.

      Section 7.5   Advances

      The Corporation shall pay sums on account of indemnification in advance of
a final  disposition  of a  Proceeding,  upon receipt of an  undertaking  by the
Director/officer to repay such sums if it is subsequently established that he is
not entitled to indemnification  pursuant to Sections 7.3 and 7.4 hereof,  which
undertaking may be accepted without  reference to the financial  ability of such
person to make repayment.

      Section 7.6   Not Exclusive

      Nothing  in  this   Article   VII  shall   limit  any  lawful   rights  to
indemnification existing independently of this Article VII.

      Section 7.7   Insurance

      The  provisions of this Article VII shall not limit the power of the Board
of Directors to authorize the purchase and maintenance of insurance on behalf of
any Director/officer  against any Expense,  whether or not the Corporation would
have the power to indemnify him against such Expense under this Article VII.

      Item 7.  Exemption from Registration Claimed

      Not Applicable.



      Item 8.  Exhibits

Number             Description

4A   1991 Isys Long Term Equity Incentive Plan.

5    Opinion of Hutchins,  Wheeler & Dittmar, A Professional Corporation,  as to
     legality of shares  being  registered  and consent of  Hutchins,  Wheeler &
     Dittmar, A Professional Corporation.

24   Consents of Independent  Accountants - included in  Registration  Statement
     under heading "Consent of Independent Accountants."

    Item 9.  Undertakings

    The undersigned Registrant hereby undertakes the following:

    (a)  The undersigned Registrant hereby undertakes:

             (1) To file,  during any period in which  offers or sales are being
made, a post-effective amendment to this registration statement:

                    (i)       To include any prospectus required by Section 
                              10(a)(3) of the Securities Act of 1933;

                   (ii)       To reflect in the  prospectus  any facts or events
                              arising   after   the   effective   date   of  the
                              registration   statement   (or  the  most   recent
                              post-effective     amendment    thereof)    which,
                              individually  or in  the  aggregate,  represent  a
                              fundamental change in the information set forth in
                              the registration statement;

                  (iii)       To include any material  information  with respect
                              to  the  plan  of   distribution   not  previously
                              disclosed  in the  registration  statement  or any
                              material   change  to  such   information  in  the
                              registration statement.

Provided,  however, that paragraphs (a)(l)(i) and (a)(l)(ii) do not apply if the
information  required  to be  included in a  post-effective  amendment  by those
paragraphs is contained in periodic reports filed by the registrant  pursuant to
section  13 or section  15(d) of the  Securities  Exchange  Act of 1934 that are
incorporated by reference in the registration statement.

             (2) That,  for the purpose of determining  any liability  under the
Securities Act of 1933, each such post-effective amendment shall be deemed to be
a new registration statement relating to the securities offered therein, and the
offering of such  securities at that time shall be deemed to be the initial bona
fide offering thereof.

             (3) To  remove  from  registration  by  means  of a  post-effective
amendment  any of the  securities  being  registered  which remain unsold at the
termination of the offering.

    (b) The  undersigned  registrant  hereby  undertakes  that,  for purposes of
determining  any liability  under the Securities Act of 1933, each filing of the
registrant's  annual  report  pursuant to section  13(a) or section 15(d) of the
Securities  Exchange  Act of 1934  (and,  where  applicable,  each  filing of an
employee  benefit  plan's  annual  report  pursuant  to  section  15(d)  of  the
Securities  Exchange  Act of 1934)  that is  incorporated  by  reference  in the
registration statement shall be deemed to be a new






registration  statement  relating to the  securities  offered  therein,  and the
offering of such  securities at that time shall be deemed to be the initial bona
fide offering thereof.

    (c)  The  undersigned   registrant  hereby  undertakes,   that,  insofar  as
indemnification  for liabilities arising under the Securities Act of 1933 may be
permitted to  directors,  officers  and  controlling  persons of the  registrant
pursuant to the foregoing  provisions,  or otherwise,  the  registrant  has been
advised  that in the opinion of the  Securities  and  Exchange  Commission  such
indemnification  is  against  public  policy  as  expressed  in the  Act and is,
therefore,  unenforceable. In the event that a claim for indemnification against
such liabilities  (other than the payment by the registrant of expenses incurred
or paid by a director,  officer or  controlling  person of the registrant in the
successful  defense of any  action,  suit or  proceeding)  is  asserted  by such
director,  officer or controlling person in connection with the securities being
registered, the registrant will, unless in the opinion of its counsel the matter
has been  settled by  controlling  precedent,  submit to a court of  appropriate
jurisdiction the question whether such  indemnification  by it is against public
policy as expressed in the Act and will be governed by the final adjudication of
such issue.














                                                  SIGNATURES

    Pursuant to the  requirements of the Securities Act, the Registrant has duly
caused  this  Registration   Statement  to  be  signed  on  its  behalf  by  the
undersigned,  thereto duly  authorized,  in the City of Boston,  Commonwealth of
Massachusetts, on the 29th day of March, 1996.

                                             COGNEX CORPORATION


                                             By:/s/Robert J. Shillman
                                                ------------------------------
                                                Robert J. Shillman, President,
                                                Chief Executive Officer and
                                                Chairman of the Board of
                                                Directors

                                POWER OF ATTORNEY

        KNOW ALL MEN BY THESE PRESENT that each person whose  signature  appears
below  constitutes and appoints Robert J. Shillman and John J. Rogers,  Jr., and
each of them,  with the power to act  without  the  other,  his true and  lawful
attorney-in-fact  and agent, with full power of substitution and resubstitution,
for him or in his name,  place and stead,  in any and all capacities to sign any
and all amendments or post-effective  amendments to this Registration Statement,
and to file  the  same,  with all  exhibits  thereto,  and  other  documents  in
connection therewith, with the Securities and Exchange Commission, granting unto
said  attorney-in-fact and agents, and each of them, full power and authority to
do and perform each and every act and thing requisite or necessary to be done in
and about the  premises,  as fully to all  intents  and  purposes as he might or
could  do  in  person,   hereby   ratifying   and   confirming   all  that  said
attorney-in-fact and agents or either of them, or their or his substitutes,  may
lawfully do or cause to be done by virtue hereof.

        Pursuant to the  requirements of the Securities  Act, this  Registration
Statement has been signed by the following  persons in the capacities and on the
dates indicated.

   Signature           Title                                        Date

/s/Robert J. Shillman  President, Chief Executive               March 29, 1996
- ---------------------- Officer and Chairman of the
Robert J. Shillman     Board of Directors (principal
                       executive officer)

/s/John J. Rogers, Jr. Executive Vice President,                March 29, 1996
- ---------------------- Chief Financial Officer and
John J. Rogers, Jr.    Treasurer (principal financial
                       and accounting officer)

/s/Reuben Wasserman    Director                                 March 29, 1996
- ---------------------- 
Reuben Wasserman

/s/William Krivsky     Director                                 March 29, 1996
- ---------------------- 
William Krivsky



- ---------------------- Director                                 March __, 1996
Patrick Sansonetti


/s/Anthony Sun         Director                                 March 29, 1996
- ---------------------- 
Anthony Sun

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549


                                    EXHIBITS

                                       to

                                    FORM S-8






                             REGISTRATION STATEMENT

                                      under

                           THE SECURITIES ACT OF 1933














                               COGNEX CORPORATION
             (Exact name of registrant as specified in its charter)