EXHIBIT 10B
COGNEX CORPORATION
Amendment to 1993 Stock Option Plan for Non-Employee Directors
The Cognex Corporation 1993 Stock Option Plan for Non-Employee Directors (the
“Plan”) is hereby amended as follows:

  1.   Section 8 of the Plan is hereby deleted in its entirety and the following
is substituted therefor:

“8. TRANSFERABILITY OF OPTIONS: Any Option granted pursuant to this Plan shall
not be assignable or transferable other than by will or the laws of descent and
distribution, except that an optionee may transfer Options granted under this
Plan to the optionee’s spouse or children or to a trust for the benefit of the
optionee or the optionee’s spouse or children.”

  2.   Except as modified hereby, the Plan is hereby ratified and confirmed in
all respects.

         
 
  COGNEX CORPORATION    
 
       
 
  By: \s\ Anthony J. Medaglia, Jr.
Clerk    

Adopted by the Board of Directors:
               December 16, 1997