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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" and to the
use of our report dated February 25, 2000 (except Note 12, as to which the date
is May 8, 2000) in the Registration Statement (Form S-1) and related Prospectus
of New Focus, Inc. for the registration of 4,025,000 shares of its common stock.

Our audits also included the financial statement schedule listed in Item 16(b)
of this Registration Statement. This schedule is the responsibility of the
Company's management. Our responsibility is to express an opinion based on our
audits. In our opinion, the financial statement schedule referred to above, when
considered in relation to the basic financial statements taken as a whole,
presents fairly in all material respects the information set forth therein.

                                             /s/ Ernst & Young LLP

San Jose, California
July 27, 2000