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                                                                EXHIBIT 10.30


                              FOURTH AMENDMENT TO
                      REVOLVING CREDIT AND LOAN AGREEMENT

     This FOURTH AMENDMENT TO REVOLVING CREDIT AND LOAN AGREEMENT ("Fourth
Amendment") is dated as of August 11, 1996, and is among MEDAR, INC., a
Michigan corporation (the "Company"), INTEGRAL VISION-AID, INC., a Michigan
corporation ("AID"), (successor by merger to Integral Vision-Aid, Inc., an Ohio
corporation, formerly known as Automatic Inspection Devices, Inc.), and
INTEGRAL VISION LTD., a corporation established under the laws of the United
Kingdom ("Integral"), as Borrowers, and NBD BANK, a Michigan banking
corporation ("NBD").  This Fourth Amendment amends the Revolving Credit and
Loan Agreement dated as of August 10, 1995 (as amended, the "Loan Agreement"),
as amended by the First Amendment to Revolving Credit and Loan Agreement dated
October 12, 1995 (the "First Amendment"), the Second Amendment to Revolving
Credit and Loan Agreement dated October 31, 1995 (the "Second Amendment"), and
the Third Amendment to Revolving Credit and Loan Agreement dated as of March
29, 1996 ("Third Amendment"), among the Company, AID, Integral and NBD.  The
Company, AID and Integral are collectively referred to as the "Borrowers" and
individually as a "Borrower".  Capitalized terms not otherwise defined in this
Fourth Amendment shall have the meanings given to them in the Loan Agreement.

     WHEREAS, the Borrowers have requested that NBD advance sums in excess of
the current Borrowing Base in order to build inventory for new orders and that
the authorization for equipment loans be increased, and NBD has agreed that it
will make such changes pursuant to the terms and conditions of this Fourth
Amendment.

      NOW, THEREFORE, for good and valuable consideration, the receipt and
      adequacy of
which is hereby acknowledged, the parties agree as follows:

1.  Revised Definition.

        The following definition contained in Section 1.1 of the Loan 
Agreement, as amended, is hereby amended effective August 11, 1996 to read as
follows:

      "Borrowing Base" means the sum of the following:


           (a) 80% of the book value of Eligible Accounts Receivables of the
      Borrowers and Guarantor; plus

           (b) 40% of the lower of costs or market value of Eligible Inventory
      of the Borrowers and Guarantor for calculations on or prior to December
      30, 1996 and decreasing to 25% of the lower of costs or market value of
      Eligible Inventory of the Borrowers and Guarantor for calculations on and
      after December 31, 1996.  Notwithstanding the foregoing, in no event will
      the amount advanced against Eligible Inventory exceed $7,000,000 for
      calculations on or prior to December 30, 1996 and $5,000,000 for
      calculations on or after December 31, 1996, plus




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           (c) $3,000,000 for calculations on or after August 11, 1996, but
      prior to January 31, 1997, $2,000,000 for calculations on or after
      January 31, 1997, but prior to July 31, 1997, and $0 for calculations on
      and after July 31, 1997.

      2.     Equipment Loans.  Section 2.4(a) of the Loan Agreement is hereby
amended effective August 11, 1996, to read in its entirety as follows:

      (a) Request for Loans.  Subject to the terms and conditions of this
      Agreement and at the sole discretion of NBD before July 31, 1997, NBD may
      extend term loans to, or enter into leases or conditional sales contracts
      with, either the Company or AID in a total amount not to exceed $750,000
      to be used for the acquisition of equipment.  All requests under this
      Section 2.4 must be submitted in writing to NBD, together with all
      information reasonably requested by NBD with respect to the equipment to
      be acquired.

      3. Conditions.  Notwithstanding any other term of this Fourth Amendment or
the Loan Agreement, NBD will not be required to give effect to this Fourth
Amendment unless the following conditions have been met:

         (a) NBD shall have received an amendment fee of $60,000 from the 
Borrowers prior to or simultaneously with the execution and delivery of
this Fourth Amendment.  The amendment fee is in addition to all interest and
fees otherwise payable to NBD and will be deemed to be fully earned upon
execution and delivery of this Fourth Amendment.

         (b) NBD shall have received a fully executed copy of this Fourth
Amendment.

         (c) All of the terms and conditions in Section 3.7 of the Loan 
Agreement continue to be met.

      4. Reaffirmation of Loan Agreement; Conflicts.  The parties hereto
acknowledge and agree that the terms and provisions of this Fourth Amendment,
amend, add to and constitute a part of the Loan Agreement.  Except as expressly
modified and amended by the terms of this Fourth Amendment, all of the other
terms and conditions of the Loan Agreement and all of the documents executed in
connection therewith or referred to or incorporated therein, remain in full
force and effect and are hereby ratified, confirmed and approved.  AID
specifically acknowledges and agrees that as successor by merger to Integral
Vision-AID, Inc., an Ohio corporation ("Ohio AID"), it has assumed all the
liabilities and obligations of Ohio AID to NBD, and that it is a party to, and
is liable and obligated under, the Loan Agreement and all of the documents and
instruments executed by Ohio AID in favor of NBD to the same extent as Ohio
AID.  If there is an express conflict between the terms of this Fourth
Amendment and the terms of the Loan Agreement, or any of the other agreements
or documents executed in connection therewith or referred to or incorporated
therein, the terms of this Fourth Amendment shall govern and control.  Any
reference in any other document or agreement to the Loan Agreement shall
hereafter refer to the Loan Agreement as amended by this Fourth Amendment.





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     5. Representations True.  The representations and warranties of the 
Borrowers contained in the Loan Agreement are true on the date hereof and
there does not exist any Default or Event of Default under the Loan Agreement.

     6. Expenses.  Borrowers acknowledge and agree that the Borrowers will pay
all attorneys' fees and out-of-pocket costs of NBD in connection with or with
respect to this Fourth Amendment and the conditions set forth herein.

     IN WITNESS WHEREOF, the Borrowers and NBD have executed the foregoing
document by their duly authorized officers as of the day and year first written
above.
                                                                         
                                 NBD BANK                                
                                                                         
                                 By:___________________________
                                    Richard P. Haslinger                      
                                    Its:  First Vice President                
                                                                           
                                 and                                       
                                                                           
                                 By:___________________________        
                                    Glenn Ansiel                              
                                    Its:  Assistant Vice President            
                                                                           
                                 MEDAR, INC.                               
                                                                           
                                 By:___________________________        
                                    Charles Drake                             
                                    Its:  President                           
                                                                           
                                 INTEGRAL VISION-AID, INC.                 
                                                                           
                                                                           
                                 By:___________________________        
                                    Charles Drake                             
                                    Its:  President                           
                                                                           
                                                                           
                                                                           
                                 INTEGRAL VISION LTD.                      
                                                                           
                                                                           
                                 By:___________________________        
                                    Richard Current                           
                                    Its:  Company Secretary                   



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                           REAFFIRMATION OF GUARANTY



     The undersigned, Medar Canada Ltd., hereby acknowledges the terms of this
Fourth Amendment to Revolving Credit and Loan Agreement and hereby reaffirms
each and every term of its (i) Guarantee and Postponement of Claim dated August
10, 1995, given in favor of NBD Bank with respect to the obligations of Medar,
Inc., Automatic Inspection Devices, Inc. (now known as Integral Vision-AID,
Inc.) and Integral Vision Ltd., and (ii) General Security Agreement dated as of
May 1, 1996, given in favor of NBD Bank.


                                             MEDAR CANADA LTD.


        
                                             By:____________________________
                                                Charles Drake
                                                Its:  President





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