<PAGE>
 
                                                                   EXHIBIT 10.21

                   FIRST AMENDED CHANGE IN CONTROL AGREEMENT
                   -----------------------------------------


          This First Amended Change in Control Agreement (the "Agreement") is
made and entered into as of November 9, 1998 by and between ORTEL CORPORATION,
a Delaware corporation ("Ortel"), and STEPHEN K. WORKMAN, an individual
("Executive").

                                    RECITALS
                                    --------

          A.  Ortel and Executive entered into a severance agreement dated as of
August 26, 1994 (the "Original Agreement") providing certain benefits to
Executive in the event of a change in control (as defined) of Ortel.

          B.  Ortel and Executive desire to provide further clarity to the basis
on which such benefits will be available and as a result desire to amend and
restate the Original Agreement in its entirety.

                                   AGREEMENT
                                   ---------

          NOW THEREFORE, in consideration of the above Recitals and the
covenants contained herein, Ortel and Executive agree as follows:

SECTION 23.  DEFINITION
-----------  ----------
          For purposes of this Agreement, a "Change in Control" shall mean the
occurrence of one or more of the following events:  (i) a single person or
entity or group of affiliated persons or entities (including a "group" as
defined in Section 13(d)(3) of the Securities Exchange Act of 1934, as amended
(the "1934 Act")) is or becomes, directly or indirectly, the "beneficial owner"
(as defined in Rule 13d-3 promulgated under the 1934 Act) of securities of Ortel
representing 40% or more of the total number of votes that may cast for the
election of directors of Ortel, or (ii) a merger or other business combination
of Ortel with another person or entity is consummated, or all or substantially
all of the assets of Ortel are sold to another person or entity, as a result of
which merger, combination or sale the shareholders of Ortel immediately prior to
the consummation of such transaction own, immediately after consummation of such
transaction, equity securities possessing less than 70% of the voting power of
the surviving or acquiring person or entity (or any person or entity in control
of the surviving or acquiring person or entity, the equity securities of which
are issued or transferred in such transaction), or (iii) as the result of or in
connection with any tender or exchange offer for the purchase of securities of
Ortel (other than an offer by Ortel for its securities), a merger,
consolidation, sale of assets, contested election of directors of Ortel or any
combination thereof, the persons who are directors of Ortel before such tender,
exchange offer, merger, consolidation, sale, contested election or combination
thereof cease to constitute a majority of the board of directors of Ortel or any
successor to Ortel.

                                       1
<PAGE>
 
SECTION 24.  TERMINATION PAYMENTS
-----------  --------------------
          (a) In the event that Executive's employment with Ortel is terminated
by Ortel within six months following a "Change in Control":

              (i) Ortel shall continue to pay Executive, on a monthly basis, his
basic salary as in effect immediately prior to the date of termination for the
twenty-four month period commencing on the effective date of such termination.

             (ii) Ortel shall continue to provide Executive all other benefits
as in effect immediately prior to the date of termination, including but not
limited to group health and life insurance benefits and an automobile allowance,
for the twenty-four month period commencing on the effective date of such
termination. Notwithstanding the foregoing, Ortel's obligations to provide these
benefits to Executive shall cease upon and to the extent Executive acquires
substantially similar benefits from an employer other than Ortel.

          (b) Executive may elect at any time prior to January 30 of the year
following the year in which Executive's employment is terminated within six
months of a Change in Control, to be paid a lump sum severance allowance, in
lieu of the termination payments described in Section 2(a) above, in an amount
equal to 85% of the aggregate amount of compensation remaining payment to
Executive thereunder.  Ortel shall pay such lump sum severance allowance to
Executive within thirty (30) days following such election by Executive.

          (c) For the purposes of Section 2(a), termination of Executive's
employment by Ortel shall include termination of Executive's employment by
Executive for Good Reason where "Good Reason" means the occurrence of any of the
following circumstances:

              (i) a substantial reduction in the responsibilities of Executive
but not (x) a reduction based solely upon a change in reporting structure within
Ortel, (y) reduction in Executive's title, (z) a transfer to another position
which does not adversely affect Executive's responsibilities, or (w) a change in
the Executive's status, position or duties within Ortel which change results
solely by virtue of Ortel ceasing to be a public company or becoming a
subsidiary or division of a larger corporation.

             (ii) the relocation by Ortel of Executive's offices to a location
outside of Los Angeles County or Orange County, California.

            (iii) a reduction by Ortel in Executive's annual base salary as in
effect on the date hereof or as the same being increased from time to time.

SECTION 25.  NO OBLIGATION TO MITIGATE DAMAGES
-----------  ---------------------------------
          In the event of a termination of Executive's employment within six
months of a Change in Control, Executive shall have no obligation to mitigate
damages by seeking other 

                                       2
<PAGE>
 
employment and will be entitled to continue to receive the payments and other
benefits provided for in Section 2(a) and 2(b) of this Agreement.

SECTION 26.  REIMBURSEMENT FOR TAXES
-----------  -----------------------
          In the event that Executive becomes entitled to payments or other
benefits upon termination in accordance with Section 2(a) and any such payments
or benefits will be subject to the tax (the "Excise Tax") imposed by Section
4999 of the Code (or any similar tax that may hereafter be imposed), the Company
shall pay to the Executive, at the time specified in Section 2(a), an amount in
addition to that provided for in Section 2(a) such that the net amount retained
by the Executive, after deduction of any Excise Tax on such Section 2(a)
payments or benefits and any federal, state and local income tax and Excise Tax
upon the payment of any additional amount provided for by this Section, shall be
equal to the amount provided for in Section 2(a).

SECTION 27.  ASSIGNMENT; AGREEMENT TO SURVIVE DISSOLUTION OR MERGER
-----------  ------------------------------------------------------
          Subject to Executive's right to terminate his employment, this
Agreement shall not be terminated by the voluntary or involuntary dissolution of
Ortel or by any merger where Ortel is not the surviving or resulting
corporation, or upon any transfer of all or substantially all of the business or
assets of Ortel.  In the event of any such merger or transfer, the provisions of
this Agreement shall be binding on and shall inure to the benefit of the
surviving entity or the entity to which such business or assets shall be
transferred.  This Agreement may not be assigned by Executive.

SECTION 28.  ARBITRATION
-----------  -----------
          Except as provided in Section 7 hereof, any controversy or claim
arising out of or relating to this Agreement, or breach thereof, shall be
settled by arbitration in accordance with the Rules of the American Arbitration
Association, and judgment upon any proper award rendered by the arbitrators may
be entered in any court having jurisdiction thereof.  There shall be three
arbitrators, one to be chosen directly by each party at will, and the third
arbitrator to be selected by the two arbitrators so chosen.  To the extent
permitted by the Rules of the American Arbitration Association and not limited
by Section 7 hereof, the selected arbitrators may grant equitable relief.  If
Ortel breaches its obligation under Section 2, it shall pay for all the costs of
arbitration.  Otherwise, each party shall pay the fees of the arbitrator
selected by him and of his own attorneys, and the expenses of his witnesses and
all other expenses connected with the presentation of his case, while the costs
of the arbitration including the cost of the record or transcripts thereof, if
any, administrative fees, and all other fees and costs shall be borne equally by
the parties.  Any arbitration shall be conducted in the County of either Orange
or Los Angeles, State of California.

                                       3
<PAGE>
 
SECTION 29.  CHOICE OF LAW
-----------  -------------
          The formation, construction and performance of this Agreement shall be
in accordance with the laws of the State of California.

SECTION 30.  NOTICES
-----------  -------
          Any notice to Ortel required or permitted hereunder shall be given in
writing, either by personal service or by registered or certified mail, postage
prepaid, duly addressed to the President of Ortel at Ortel's then principal
place of business.  Any such notice to Executive shall be given in a like
manner, and if mailed, shall be addressed to Executive at his residence.  For
the purpose of determining compliance with any time limit herein, a notice sent
by mail shall be deemed given on the postmark date.  Any other notice shall be
deemed given upon receipt of the notice.

SECTION 31.  SOLE AND ENTIRE AGREEMENT; SEPARABILITY
-----------  ---------------------------------------
          This Agreement constitutes the sole and entire existing agreement
between the parties and completely and correctly expresses all of the rights and
obligations of the parties.  All prior agreements are completely superseded and
revoked insofar as any such prior agreement might have given rise to any
enforceable right.  In the event any Section or portion thereof is declared
illegal, the remainder of this Agreement shall remain in full force and effect.

SECTION 32.  WAIVERS
-----------  -------
          The waiver in any particular instance or series of instances of any
term or condition of this Agreement or any breach hereof by either party shall
not constitute a waiver of such term or condition or of any breach thereof in
any other instance.

SECTION 33.  AGREEMENT
-----------  ---------
          This Agreement is subject to amendment only by subsequent written
agreement between, and executed by, the parties hereto.  Commencement or
continuation of any custom or practice shall not constitute an amendment hereof
or give additional rights to Executive or create additional obligations of Ortel
with respect to matters covered by this Agreement.

          IN WITNESS WHEREOF, the parties have executed this Agreement at
Alhambra, California.

<TABLE>
<CAPTION>
                                                      ORTEL CORPORATION
<S>                                                   <C>  
/s/ STEPHEN K. WORKMAN                                By:  /s/ WIM H.J. SELDERS
------------------------------------                     -----------------------------
Stephen K. Workman                                       Wim H.J. Selders
                                                         President and Chief Executive Officer
</TABLE>

                                       4