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                                                                    EXHIBIT 4.1

NUF

INCORPORATED UNDER THE LAWS OF THE STATE OF DELAWARE

COMMON STOCK

THIS CERTIFICATE IS TRANSFERABLE
IN BOSTON, MA AND NEW YORK, NY

CUSIP 644383 10 1
SEE REVERSE FOR CERTAIN DEFINITIONS

THIS IS TO CERTIFY THAT

is the owner of

fully paid and non-assessable shares, $.001 par value, of the COMMON STOCK of
NEW FOCUS, INC.

(hereinafter called the "Corporation"), transferable on the books of the
Corporation in person, or by duly authorized attorney, upon surrender of this
certificate properly endorsed. This certificate is not valid until countersigned
by a Transfer Agent and registered by a Registrar.

WITNESS the facsimile seal of the Corporation and the facsimile signatures of
its duly authorized officers.

Dated:

SECRETARY

PRESIDENT AND CHIEF EXECUTIVE OFFICER

COUNTERSIGNED AND REGISTERED:
EQUISERVE TRUST COMPANY, N.A.
TRANSFER AGENT
AND REGISTRAR

BY
AUTHORIZED SIGNATURE







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NEW FOCUS, INC.

The Company will furnish without charge to each stockholder who so requests, a
copy of the designations, powers, preferences and relative, participating,
optional or other special rights of each class of stock or series thereof and
the qualifications, limitations or restrictions of such preferences and/or
rights. Any such requests may be addressed to the Secretary of the Corporation.

The following abbreviations, when used in the inscription on the face of this
certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

TEN COM -- as tenants in common
TEN ENT -- as tenants by the entireties
JT TEN  -- as joint tenants with right of
           survivorship and not as tenants
           in common

UNIF GIFT MIN ACT-D - ______________________ Custodian ____________________
                               (Cust)                         (Minor)
                      under Uniform Gifts to Minors
                      Act _________________________________________________
                                              (State)

Additional abbreviations may also be used though not in the above list.

For Value Received, _______________________________ hereby sell, assign and
transfer unto

PLEASE INSERT SOCIAL SECURITY OR OTHER
IDENTIFYING NUMBER OF ASSIGNEE

______________________________________

______________________________________

________________________________________________________________________________
                  (PLEASE PRINT OR TYPEWRITE NAME AND ADDRESS,
                   INCLUDING ZIP OR POSTAL CODE, OF ASSIGNEE)

________________________________________________________________________________

________________________________________________________________________________


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_________________________________________________________________________ Shares
of the Common Stock represented by the within certificate, and do hereby
irrevocably constitute and appoint Attorney to transfer the said stock on the
books of the within named Corporation with full power of substitution in the
premises.

Dated ___________________________________

NOTICE: THE SIGNATURE TO THIS ASSIGNMENT MUST CORRESPOND WITH THE NAME AS
        WRITTEN UPON THE FACE OF THE CERTIFICATE IN EVERY PARTICULAR, WITHOUT
        ALTERATION OR ENLARGEMENT OR ANY CHANGE WHATEVER.

Signature(s) Guaranteed:

________________________________________________________________________________

THE SIGNATURE(S) MUST BE GUARANTEED BY AN ELIGIBLE GUARANTOR INSTITUTION (BANKS,
STOCKBROKERS, SAVINGS AND LOAN ASSOCIATIONS AND CREDIT UNIONS WITH MEMBERSHIP IN
AN APPROVED SIGNATURE GUARANTEE MEDALLION PROGRAM), PURSUANT TO S.E.C. RULE
17Ad-15.

KEEP THIS CERTIFICATE IN A SAFE PLACE. IF IT IS LOST, STOLEN, MUTILATED OR
DESTROYED, THE CORPORATION WILL REQUIRE A BOND OF INDEMNITY AS A CONDITION TO
THE ISSUANCE OF A REPLACEMENT CERTIFICATE.