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EXHIBIT 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the reference to our firm under the caption "Experts" in the
Registration Statement (Form S-3) and related Prospectus of Photon Dynamics,
Inc. for the registration of 1,295,000 shares of its common stock and to the use
of our report dated October 20, 2000, with respect to the consolidated financial
statements of Photon Dynamics, Inc. included in its Annual Report on Form 10-K
for the year ended September 30, 2000, filed with the Securities and Exchange
Commission.
/s/ Ernst & Young LLP
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San Jose, California
November 7, 2000
