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EXHIBIT 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the incorporation by reference to our firm in the Registration
Statement on Form S-8 pertaining to the Credence Systems Corporation
Supplemental Stock Option Plan, Credence Systems Corporation 1993 Stock Option
Plan and Credence Systems Corporation Employee Stock Purchase Plan of Credence
Systems Corporation, of our report dated November 24, 1999, with respect to the
consolidated financial statements and schedule of Credence Systems Corporation
included in the Annual Report (Form 10-K/A) for the year ended October 31, 1999,
filed with the Securities and Exchange Commission.
/s/ Ernst & Young LLP
ERNST & YOUNG LLP
San Jose, California
November 21, 2000
