UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                            SCHEDULE 14A INFORMATION

                  Proxy Statement Pursuant to Section 14(a) of
              the Securities Exchange Act of 1934 (Amendment No. )

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     14a-6(e)(2))

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|X|  Definitive Additional Materials

|_|  Soliciting Material Pursuant to ss.240.14a-11(c) or ss.240.14a-12

                            NANOMETRICS INCORPORATED
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                (Name of Registrant as Specified In Its Charter)


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    (Name of Person(s) Filing Proxy Statement, if other than the Registrant)

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                            NANOMETRICS INCORPORATED

                               1550 Buckeye Drive
                           Milpitas, California 95035

                                  May 20, 2004

                               -------------------

                          SUPPLEMENT TO PROXY STATEMENT
                                       FOR
                       2004 ANNUAL MEETING OF SHAREHOLDERS
                           To Be Held On May 26, 2004

                               -------------------

     This Supplement  amends the Notice of Annual Meeting of Shareholders  dated
April 23, 2004 and the  accompanying  Proxy  Statement  (the "Proxy  Statement")
furnished  in  connection  with the  solicitation  of  proxies  by the  Board of
Directors (the "Board") of Nanometrics  Incorporated,  a California  corporation
(the  "Company"),   for  use  at  its  2004  Annual  Shareholders  Meeting  (the
"Meeting"),  to be held on May 26, 2004 at the principal  offices of the Company
located  at  1550  Buckeye  Drive,  Milpitas,   California  95035,  and  at  any
adjournment or postponement of the Meeting.

     The information  contained in this Supplement should be read in conjunction
with the Proxy Statement. There is no change in the time or place of the Meeting
or the record date to determine  shareholders  entitled to notice of and to vote
at the Meeting.

     Change in the Number of Directors

     On May 14, 2004,  Mircea V. Dusa,  who was  appointed to the Board on April
14, 2004 to fill a vacancy,  informed the Board that for personal reasons he had
determined not to stand for re-election  and resigned from the Board.  The Board
has determined not to nominate a substitute nominee.

     Consequently, the Meeting's purpose will be:

     1.   To elect six  directors  to serve  until the next  Annual  Meeting  of
          Shareholders or until their successors are elected.

     2.   To ratify the  appointment  of  Deloitte  & Touche LLP as  independent
          auditors of the Company for the fiscal year ending January 1, 2005.

     3.   To  transact  such other  business  as may  properly  come  before the
          meeting or any adjournment thereof.

     Mr. Dusa is no longer a nominee for election to the Board. All of the other
nominees listed in the Proxy Statement have consented to serve if elected.

     No new proxy card is enclosed with this  Supplement or  distributed  to the
shareholders.  A card was  delivered  to the  shareholders  along with the Proxy
Statement  and that  proxy  card may still be used.  A vote  "For" the  nominees
listed on the proxy card will not be  considered as a vote for Mr. Dusa since he
is no longer a nominee and has indicated that he will not serve if elected.

     Shareholders  are encouraged to direct any questions  about this Supplement
or how to complete  and return  proxy cards to the  Secretary  of the Company at
(408) 435-9600.

                                                              Vincent J. Coates
                                                              Secretary

     Milpitas, California
     May 20, 2004