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                                                                    EXHIBIT 02.4

                                 PROMISSORY NOTE

$5,582,501.10                                                  November 28, 2001

         FOR VALUE RECEIVED, the undersigned, JOSEPH Y. LIU, hereby
unconditionally promises to pay to the order of OPLINK COMMUNICATIONS, INC., a
Delaware corporation ("Oplink", the "Company" or "Holder"), at such place as
Holder hereof may designate, in lawful money of the United States of America and
in immediately available funds, the principal sum of $5,582,501.10 together with
simple interest accrued from the date hereof on the unpaid principal at the rate
of 6.5% per annum, calculated on the basis of a 365-day year for the actual
number of days elapsed.

         1. Principal Repayment. The outstanding principal amount and any
accrued and unpaid interest hereunder shall be due and payable in one lump sum
on the earlier of (i) demand by the Company, or (ii) the fifth anniversary of
the date hereof; provided, however, that in the event that the undersigned's
association with the Company either as an employee or a member of the Board of
Directors of the Company is terminated, the entire principal balance and all
accrued interest shall become immediately due and payable, and immediately
collectible by Holder pursuant to applicable law (the "Maturity Date").

         2. Prepayment. This Note may be prepaid at any time without penalty.
All money paid toward the satisfaction of this Note shall be applied first to
the payment of interest as required hereunder and then to the retirement of the
principal.

         3. Escrow; Full Recourse Note. This Note is secured by the same escrow
created in connection with those certain Promissory Notes dated April 3, 2001
(the "April 2001 Note") and November 27, 2001 (the "27 November 2001 Note),
respectively, issued by the undersigned in favor of Oplink, and any additional
shares of Oplink common stock covered by the stock options (the "Stock Options")
granted and to be granted to the undersigned in connection with his employment
or directorship with the Company (the "Escrow"). As the Stock Options have
vested and continue to vest from time to time, the Oplink shares so vested shall
be placed into the Escrow. Any such shares already purchased shall be pledged by
the undersigned, upon the execution of this Note, in favor of the Holder
pursuant to the Stock Pledge Agreement attached hereto and, if the undersigned
elects to purchase any more of the vested shares, the shares so purchased shall
be likewise pledged from time to time. Should the undersigned wish to sell any
of the Oplink stock so purchased before the Maturity Date, the proceeds realized
therefrom shall be applied in the following order: (i) to prepay or repay (as
the case may be) the April 2001 Note in full, (ii) to prepay or repay (as the
case may be) the 27 November 2001 Note in full, and (iii) to prepay this Note,
until it is settled in full. In the event that the undersigned's employment or
directorship with the Company is terminated, should any principal amount or any
accrued and unpaid interest under this Note remain due and payable, Holder has
the right (but not the obligation) to require the undersigned to sell any or all
of the Oplink common stock in the Escrow immediately and to first apply the
proceeds realized therefrom in the following order: (i) to prepay or repay (as
the case may be) the April 2001 Note in full, (ii) to prepay or repay (as the
case may be) the 27 November 2001 Note in full, and (iii) to repay this Note,
until it is settled in

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full. The undersigned shall be solely responsible for any tax consequences to
him arising from his optioned shares being so escrowed, pledged and/or sold, as
the case may be. Notwithstanding the foregoing, this Note is full recourse,
accordingly, Holder shall be entitled to seek personal judgement against the
undersigned in the event of a default for the full amount of the principal and
accrued interest then outstanding, plus any costs or expenses as provided
herein.

         4. Non-Consumer Debt. The undersigned hereby represents and agrees that
the amounts due under this Note are not consumer debt, and are not incurred
primarily for personal, family or household purposes, but are for business and
commercial purposes only.

         5. Waiver. The undersigned hereby waives presentment, protest and
notice of protest, demand for payment, notice of dishonor and all other notices
or demands in connection with the delivery, acceptance, performance, default or
endorsement of this Note.

         6. Expenses; Attorneys' Fees. The Holder hereof shall be entitled to
recover, and the undersigned agrees to pay when incurred, all costs and expenses
of collection of this Note, including without limitation, reasonable attorneys'
fees.

         7. Governing Law. This Note shall be governed by, and construed,
enforced and interpreted in accordance with, the laws of the State of
California, excluding conflict of laws principles that would cause the
application of laws of any other jurisdiction.




                                        ________________________________________
                                        Joseph Y. Liu



                                        Accepted By Oplink Communications, Inc.:



                                        ________________________________________
                                        Bruce Horn
                                        Chief Financial Officer

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