SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549



                                  SCHEDULE 13G/A
                    UNDER THE SECURITIES EXCHANGE ACT OF 1934
                                 (AMENDMENT NO. 5)


                             Cyberoptics Corporation
             ------------------------------------------------------
                                 (NAME OF ISSUER)


                     COMMON STOCK, NO PAR VALUE PER SHARE
             ------------------------------------------------------
                          (TITLE OF CLASS OF SECURITIES)


                                    232517102
             ------------------------------------------------------
                                 (CUSIP NUMBER)

Check the appropriate box to designate the rule pursuant to which this Schedule
is filed:

[ ]  Rule 13d-1(b)

[ ]  Rule 13d-1(c)

[ ]  Rule 13d-1(d)


The  remainder  of this cover page shall be filled out for a reporting  person's
initial filing on this form with respect to the subject class of securities, and
for any  subsequent  amendment  containing  information  which  would  alter the
disclosures provided in a prior cover page.

The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the  Securities  Exchange  Act of
1934 ("Act") or otherwise  subject to the liabilities of that section of the Act
but  shall be  subject  to all other  provisions  of the Act  (however,  see the
notes).





- --------------------------------------------------------------
  1   NAME OF REPORTING PERSONS
      S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

      EQSF ADVISERS, INC.

      (EIN 13-3354359)

- --------------------------------------------------------------
- --------------------------------------------------------------
  2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
       (a)  [  ]
       (b)  [  ]
- --------------------------------------------------------------
- --------------------------------------------------------------
  3   SEC USE ONLY

- --------------------------------------------------------------
- --------------------------------------------------------------
  4   CITIZENSHIP OR PLACE OF ORGANIZATION

                           NEW YORK CORPORATION

- --------------------------------------------------------------
- --------------------------------------------------------------
                   5 SOLE VOTING POWER

                           864,300
   NUMBER OF     ---------------------------------------------
                 ---------------------------------------------
     SHARES        6  SHARED VOTING POWER
  BENEFICIALLY
    OWNED BY               NONE
                 ---------------------------------------------
                 ---------------------------------------------
      EACH         7  SOLE DISPOSITIVE POWER
   REPORTING
     PERSON                1,141,800

                 ---------------------------------------------
                 ---------------------------------------------
      WITH        8   SHARED DISPOSITIVE POWER

                           NONE
- --------------------------------------------------------------
- --------------------------------------------------------------
 9    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
      PERSON

           1,141,800
- --------------------------------------------------------------
- --------------------------------------------------------------
 10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
      CERTAIN SHARES*
             [    ]

- --------------------------------------------------------------
- --------------------------------------------------------------
 11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

           14.02%
- --------------------------------------------------------------
- --------------------------------------------------------------
 12   TYPE OF REPORTING PERSON*

           IA
- --------------------------------------------------------------




- --------------------------------------------------------------
  1   NAME OF REPORTING PERSONS
      S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

      M.J. WHITMAN ADVISERS, INC.

      (EIN 13-3686379)

- --------------------------------------------------------------
- --------------------------------------------------------------
  2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
       (a)  [  ]
       (b)  [  ]
- --------------------------------------------------------------
- --------------------------------------------------------------
  3   SEC USE ONLY

- --------------------------------------------------------------
- --------------------------------------------------------------
  4   CITIZENSHIP OR PLACE OF ORGANIZATION

                               NEW YORK CORPORATION

- --------------------------------------------------------------
- --------------------------------------------------------------
                  5 SOLE VOTING POWER

                               11,750
   NUMBER OF     ---------------------------------------------
                 ---------------------------------------------
     SHARES        6  SHARED VOTING POWER
  BENEFICIALLY
    OWNED BY                   NONE
                 ---------------------------------------------
                 ---------------------------------------------
      EACH         7  SOLE DISPOSITIVE POWER
   REPORTING
     PERSON                    11,750
                 ---------------------------------------------
                 ---------------------------------------------
      WITH        8   SHARED DISPOSITIVE POWER

                               NONE
- --------------------------------------------------------------
- --------------------------------------------------------------
 9    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
      PERSON

         11,750
- --------------------------------------------------------------
- --------------------------------------------------------------
 10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
      CERTAIN SHARES*
             [    ]

- --------------------------------------------------------------
- --------------------------------------------------------------
 11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

         0.14%
- --------------------------------------------------------------
- --------------------------------------------------------------
 12   TYPE OF REPORTING PERSON*

         IA
- --------------------------------------------------------------




- --------------------------------------------------------------
  1   NAME OF REPORTING PERSONS
      S.S. OR I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS

           MARTIN J. WHITMAN

- --------------------------------------------------------------
- --------------------------------------------------------------
  2   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
        (a)  [  ]
        (b)  [  ]
- --------------------------------------------------------------
- --------------------------------------------------------------
  3   SEC USE ONLY

- --------------------------------------------------------------
- --------------------------------------------------------------
  4   CITIZENSHIP OR PLACE OF ORGANIZATION

                           USA
- --------------------------------------------------------------
- --------------------------------------------------------------
                   5 SOLE VOTING POWER

   NUMBER OF               NONE  (SEE ITEM 4)
                 ---------------------------------------------
                 ---------------------------------------------
                   6 SHARED VOTING POWER
     SHARES
                           NONE
  BENEFICIALLY
    OWNED BY
                 ---------------------------------------------
                 ---------------------------------------------
      EACH         7  SOLE DISPOSITIVE POWER

   REPORTING               NONE  (SEE ITEM 4)
                 ---------------------------------------------
                 ---------------------------------------------
  PERSON WITH     8   SHARED DISPOSITIVE POWER

                           NONE
- --------------------------------------------------------------
- --------------------------------------------------------------
 9    AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING
      PERSON

           -0-    (SEE ITEM 4)
- --------------------------------------------------------------
- --------------------------------------------------------------
 10   CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES
      CERTAIN SHARES*
             [  ]

- --------------------------------------------------------------
- --------------------------------------------------------------
 11   PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

           -0-
- --------------------------------------------------------------
- --------------------------------------------------------------
 12   TYPE OF REPORTING PERSON*

           IN
- --------------------------------------------------------------



ITEM 1.

     (A) NAME OF ISSUER:

         Cyberoptics Corporation (the "Issuer").

     (B) ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES OR,IF NONE, RESIDENCE:

         5900 Golden Hills Drive, Minneapolis, MN 55416

ITEM 2.

     (A) NAME OF PERSON FILING:

     This schedule is being jointly filed by EQSF Advisers,  Inc. ("EQSF"), M.J.
Whitman  Advisers,  Inc.  ("MJWA") and Martin J.  Whitman,  the Chief  Executive
Officer of EQSF and Chief Investment  Officer of MJWA and controlling  person of
EQSF and MJWA.  (EQSF,  MJWA and Martin J.  Whitman are  sometimes  collectively
referred to hereinafter as "Filer").  Attached hereto as an exhibit is a copy of
the joint Schedule 13G filing agreement among the reporting persons.

     (B) ADDRESS OF PRINCIPAL BUSINESS OFFICE:

     The address of the principal executive office of EQSF, MJWA and Mr. Whitman
is: 767 Third Avenue, New York, New York 10017-2023.

     (C) CITIZENSHIP:

         The  citizenship  or place  of  organization  of each of the  reporting
persons is as follows:

         EQSF

         New York State Corporation.

         MJWA

         New York State Corporation.

         MARTIN J. WHITMAN

         United States Citizen.

     (D) TITLE OF CLASS OF SECURITIES:

         Common Stock, no par value per share.

     (E) CUSIP NUMBER:

         232517102

ITEM 3. IF THIS  STATEMENT  IS  BEING  FILED  PURSUANT  TO  RULES  13D-1(B),  OR
13D-2(B), CHECK WHETHER THE PERSON FILING IS A:

         (E) Investment  Adviser  registered under section 203 OF THE INVESTMENT
ADVISERS ACT OF 1940 (EQSF and MJWA).

ITEM 4.  OWNERSHIP.

     (a) & (b) EQSF  beneficially  owns 1,141,800 shares, or 14.02% of the class
of securities of the issuer.  MJWA  beneficially owns 11,750 shares, or 0.14% of
the class of securities of the issuer.

           (c)    (i) EQSF:   864,300
                      MJWA:    11,750

                 (ii) Not applicable.

                (iii) EQSF: 1,141,800
                      MJWA:    11,750

                 (iv) Not applicable.

     Mr.  Whitman  disclaims  beneficial  ownership  of all
such shares.

ITEM 5.  OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.

     If this  statement  is being  filed to report  the fact that as of the date
hereof the reporting  person has ceased to be the beneficial  owner of more than
five percent of the class of securities, check the following [ ].

ITEM 6.  OWNERSHIP  OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.

     Third Avenue  Small-Cap Value Portfolio of the Met Investors  Series Trust,
an investment  company  registered under the Investment Company Act of 1940, has
the right to receive dividends from, and the proceeds from the sale of, 4,900 of
the shares  reported by EQSF,  Third Avenue  Small-Cap Value Fund, an investment
company  registered  under the Investment  Company Act of 1940, has the right to
receive dividends from, and the proceeds from the sale of, 514,600 of the shares
reported by EQSF,  Third  Avenue  Value  Portfolio  of the WRL Series  Fund,  an
investment  company registered under the Investment Company Act of 1940, has the
right to receive  dividends  from, and the proceeds from the sale of, 135,400 of
the  shares  reported  by  EQSF,   American  Express  Partners  Small-Cap  Value
Portfolio,  an investment company registered under the Investment Company Act of
1940, has the right to receive dividends from, and the proceeds from the sale of
254,100 of the shares reported by EQSF,  Third Avenue Variable  Portfolio of the
Third Avenue Variable Series Trust, an investment  company  registered under the
Investment Company Act of 1940, has the right to receive dividends from, and the
proceeds  from the sale of  194,400  of the shares  reported  by EQSF,  American
Express Variable Annuity,  an investment company registered under the Investment
Company Act of 1940, has the right to receive  dividends  from, and the proceeds
from  the  sale  of  23,400  of the  shares  reported  by  EQSF,  and  Integrity
Life/Legends Third Avenue Value Fund, an investment company registered under the
Investment Company Act of 1940, has the right to receive dividends from, and the
proceeds from the sale of 15,000 of the shares reported by EQSF. Various clients
for whom MJWA acts as  investment  advisor  have the right to receive  dividends
from, and the proceeds of the sale of, the shares reported by MJWA.

ITEM 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
        SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.

         Not Applicable.

ITEM 8.  IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.

         Not applicable.

ITEM 9.  NOTICE OF DISSOLUTION OF GROUP.

         Not applicable.

ITEM 10. CERTIFICATION.

         By  signing  below I  certify  that,  to the best of my  knowledge  and
belief, the securities referred to above were acquired in the ordinary course of
business  and were not acquired for the purpose of and do not have the effect of
changing or  influencing  the control of the issuer of such  securities and were
not acquired in connection  with or as a participant in any  transaction  having
such purposes or effect.


                                    SIGNATURE

         After reasonable  inquiry and to the best of my knowledge and belief, I
certify that the information  set forth in this statement is true,  complete and
correct.

                            July 10, 2002
                         ---------------------------
                            (Date)




                         EQSF ADVISERS, INC.

                         BY:/S/ MARTIN J. WHITMAN
                            ------------------------
                            Martin J. Whitman
                            Chairman and Chief Executive Officer


                         M.J. WHITMAN ADVISERS, INC.

                         BY:/S/  MARTIN J. WHITMAN
                            ----------------------
                            Martin J. Whitman
                            Chairman and Chief Investment Officer



                            /S/  MARTIN J. WHITMAN
                            -----------------------
                            Martin J. Whitman, President