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                                                                   EXHIBIT 10.21

                                JANUARY 25, 2005

                            INFINEON TECHNOLOGIES AG

                               FINISAR CORPORATION

                          =============================

                              AMENDED AND RESTATED
                          REGISTRATION RIGHTS AGREEMENT
                                   RELATING TO
                               FINISAR CORPORATION

                          =============================

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                                    CONTENTS

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CLAUSE                                                                PAGE
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1.       DEFINITIONS...............................................     1

2.       REQUIRED REGISTRATIONS....................................     3

3.       INCIDENTAL REGISTRATION...................................     6

4.       REGISTRATION PROCEDURES...................................     7

5.       UNDERWRITTEN OFFERINGS....................................    11

6.       ALLOCATION OF EXPENSES....................................    12

7.       INDEMNIFICATION AND CONTRIBUTION..........................    13

8.       STAND-OFF AGREEMENT.......................................    16

9.       LIMITATIONS ON SUBSEQUENT REGISTRATION RIGHTS.............    16

10.      RULE 144 REQUIREMENTS.....................................    17

11.      MERGERS, ETC..............................................    17

12.      STOCKHOLDER AGREEMENT.....................................    17

13.      TERMINATION...............................................    17

14.      TRANSFERS OF RIGHTS.......................................    18

15.      NOTICES...................................................    18

16.      ENTIRE AGREEMENT..........................................    19

17.      AMENDMENTS AND WAIVERS....................................    19

18.      COUNTERPARTS..............................................    19

19.      SEVERABILITY..............................................    20

20.      GOVERNING LAW.............................................    20

21.      ARBITRATION...............................................    20

22.      HEADINGS..................................................    20
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AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT, dated January 25, 2005 (this
AGREEMENT), between INFINEON TECHNOLOGIES AG, a company organized under the laws
of the Federal Republic of Germany, and whose principal place of business is at
St.-Martin-Stra(beta)e 53, 81541 Munchen, Germany (INFINEON) and FINISAR
CORPORATION, a corporation organized under the laws of the State of Delaware,
and whose principal place of business is at 1308 Moffett Park Drive, Sunnyvale,
CA 94089, U.S.A. (the COMPANY).

      WHEREAS, Infineon and the Company previously entered into a Master
Purchase and Sale Agreement dated April 29, 2004 and an Amended and Restated
Master Purchase and Sale Agreement dated January 25, 2005 (together, the
ORIGINAL AGREEMENTS);

      WHEREAS, in connection with the Original Agreements, Infineon entered into
Registration Rights Agreement dated April 29, 2004 (the ORIGINAL REGISTRATION
RIGHTS AGREEMENT);

      WHEREAS, Infineon and the Company have entered into a Master Sale and
Purchase Agreement dated the same date as this Agreement (the SALE AND PURCHASE
AGREEMENT) which supersedes the Original Agreements and pursuant to which the
Company will issue to Infineon shares of the Common Stock, $0.001 par value, of
the Company (the COMMON STOCK); and

      WHEREAS, the Company and Infineon desire to amend and restate in its
entirety the Original Registration Rights Agreement to provide for certain
arrangements with respect to the registration under the Securities Act of the
shares of Common Stock issued to Infineon by the Company in connection with the
transactions contemplated by the Sale and Purchase Agreement;

NOW, THEREFORE, in consideration of the mutual promises and covenants contained
in this Agreement and the Sale and Purchase Agreement, the parties agree that
the Original Registration Rights Agreement is amended and restated in its
entirety to read as follows:

1.    DEFINITIONS

1.1   As used in this Agreement, the following terms shall have the following
respective meanings:

CLOSING has the meaning given in the Sale and Purchase Agreement;

COMMISSION means the United States Securities and Exchange Commission or any
other federal agency at the time administering the Securities Act;

CUTBACK REGISTRATION means any Required Registration or any other registration
(other than a registration on Form S-8, Form S-4 or Form F-4, their successors,
any other form for a similar limited purpose or any registration statement
covering only securities proposed to be issued in exchange for securities or
assets of another corporation or entity) to be effected as an underwritten
Public Offering in which the managing underwriter with respect thereto advises
the Company and Infineon in

                                                                          Page 1

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writing that, in its good faith opinion, the number of securities requested to
be included in such registration (including securities of the Company which are
not Registrable Shares) exceed the number which can be sold in such offering
without a material reduction in the selling price anticipated to be received for
the securities to be sold in such Public Offering;

EXCHANGE ACT means the United States Securities Exchange Act of 1934, as
amended, and the rules and regulations of the Commission issued under such Act,
as they each may, from time to time, be in effect;

INCIDENTAL REGISTRATION means any registration of Registrable Shares under the
Securities Act effected in accordance with Section 3.

LONG FORM means Form F-1, Form S-1, Form F-2 or Form S-2, as may be appropriate,
promulgated by the Commission under the Securities Act, or any successor or
similar registration statement;

PERSON means an individual, partnership, corporation, trust or unincorporated
organization or any federal, state, local or foreign government or any political
subdivision thereof (including, without limitation, the executive and
legislative branches thereof) or any department, commission, board, bureau,
agency, court, panel or other instrumentality of any kind of any of the
foregoing;

PUBLIC OFFERING means any offering of Shares to the public, either on behalf of
the Company or any of its securityholders, pursuant to an effective registration
statement under the Securities Act;

REGISTRABLE SHARES means:

(a)   any Shares issued to Infineon in accordance with the Sale and Purchase
      Agreement,

(b)   any other Shares issued or issuable in respect of such Shares (because of
      share splits, stock dividends, reclassifications, recapitalizations, or
      similar events), and

(c)   any Shares issued or issuable to Infineon as a result of the exercise by
      Infineon of any statutory or contractual pre-emptive or other contractual
      or legal right;

provided, further, that Shares which are Registrable Shares shall cease to be
Registrable Shares

(a)   upon any sale pursuant to a Registration Statement or Rule 144 under the
      Securities Act,

(b)   on such date as such Registrable Shares could be sold pursuant to Rule
      144(k), or

(c)   upon any sale in any manner to a Person which, by virtue of Section 14 of
      this Agreement, is not entitled to the rights provided by this Agreement;

                                                                          Page 2

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REGISTRATION STATEMENT means a registration statement filed by the Company with
the Commission under the Securities Act for a public offering and sale of Shares
(other than a registration statement on Form S-8, Form S-4 or Form F-4, their
successors, any other form for a similar limited purpose or any registration
statement covering only securities proposed to be issued in exchange for
securities or assets of another corporation);

REGISTRATION EXPENSES means the expenses described in Section 6;

REQUIRED REGISTRATION means any registration of Registrable Shares under the
Securities Act effected in accordance with Section 2.2;

SECURITIES ACT means the United States Securities Act of 1933, as amended, and
the rules and regulations of the Commission issued under such Act, as they each
may, from time to time, be in effect;

SHARES means shares of the Common Stock;

SHELF REGISTRATION means a registration under Rule 415 of the Securities Act
required to be effected on a Short Form;

SHELF REGISTRATION STATEMENT means a Short Form filed as a Shelf Registration;
and

SHORT FORM means Form S-3 promulgated by the Commission under the Securities
Act, or any successor or similar short-form registration statement.

2.    REQUIRED REGISTRATIONS

2.1   Short Form Registration

(a)   The Company shall (i) as expeditiously as reasonably possible (but in any
      event not later than February 7, 2005) file a Shelf Registration
      Statement, including a preliminary prospectus, covering all Registrable
      Shares issued or issuable under the Sale and Purchase Agreement with the
      Commission, and (ii) use its reasonable best efforts to cause such
      Registration Statement to be declared effective as soon as practicable
      after its filing with the Commission but in no event more than 30 days
      after the Closing.

(b)   The Company agrees to use its reasonable best efforts to keep the Shelf
      Registration Statement continuously effective until the termination of
      this Agreement pursuant to Section 13. The Company further agrees, if
      necessary, to supplement or amend the Shelf Registration Statement, if
      required by the rules, regulations or instructions applicable to the
      registration form used by the Company for such Shelf Registration
      Statement or by the Securities Act or by any other rules and regulations
      thereunder for shelf registration.

(c)   If requested by Infineon, the method of disposition of all Registrable
      Shares included in such registration shall be an underwritten offering
      effected in accordance with Section 5.

                                                                          Page 3

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2.2   Long Form Registration

(a)   If at any time (i) prior to the termination of this Agreement under
      Section 13 the Company becomes ineligible to file or maintain the Shelf
      Registration Statement, or the Shelf Registration Statement for any other
      reason ceases to be effective, Infineon may request the Company, in
      writing, to effect the registration of Registrable Shares owned by
      Infineon on a Long Form (which can at the Company's discretion be made on
      a Short Form if available).

(b)   Thereupon, the Company shall, as expeditiously as reasonably possible, use
      its reasonable best efforts to effect the registration of all Registrable
      Shares which the Company has been requested to so register on a Long Form,
      provided, however, that the Company shall not be required to effect any
      registration of Registrable Shares unless Registrable Shares are proposed
      to be offered at an aggregate proposed offering price net of underwriting
      commissions of at least $25,000,000 (based on the then current public
      market price, if any).

(c)   If requested by Infineon, the method of disposition of all Registrable
      Shares included in such registration shall be an underwritten offering
      effected in accordance with Section 5.

2.3   Limitations on Required Registration

(a)   The Company shall not be required to effect more than five registrations
      in the aggregate pursuant to Section 2.2 provided, however, that, Infineon
      may not make more than one request pursuant to Section 2.2 in any three
      (3) month period.

(b)   The Company shall not be required to effect any registration (other than
      on a Short Form or any successor form relating to secondary offerings)
      within six (6) months after the effective date of any other Registration
      Statement of the Company.

(c)   The Company shall not be required to effect a registration pursuant to
      Section 2.2 if the request by Infineon contravenes, breaches or violates
      any stand-off agreements executed by Infineon or if effecting the
      registration would cause the Company to violate or breach any stand-off
      agreement executed in good faith by the Company in connection with any
      Public Offering or any other sale of its equity securities.

(d)   A registration shall not be deemed to have been effected for purposes of
      this Section 2,

       (i)   unless a Registration Statement with respect thereto has become
             effective; provided, however, a registration which does not become
             effective after the Company has filed a Registration Statement with
             respect thereto because it has been withdrawn at the request of
             Infineon shall be deemed to have been effected by the Company
             unless Infineon complies with the provisions of Section 6;

                                                                          Page 4

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       (ii)  if, after it has become effective, such Registration Statement
             becomes subject to any stop order, injunction or other requirement
             of the Commission or other governmental agency or court for any
             reason; or

       (iii) if the conditions to closing specified in the purchase agreement or
             underwriting agreement, as the case may be, entered into in
             connection with such registration are not satisfied, other than by
             reason of some act or omission by Infineon.

2.4   Postponement or Pre-emption of Required Registration

(a)   If at the time of any request to register Registrable Shares pursuant to
      Section 2.2, the Company shall furnish to Infineon a certificate signed by
      the Chief Executive Officer of the Company stating that:

       (i)   the Company is engaged or has fixed plans to engage, within sixty
             (60) days of the time of the request, in a registered Public
             Offering as to which Infineon may include Registrable Shares
             pursuant to Section 3; or

       (ii)  in the good faith judgment of the Board of Directors of the
             Company, the filing of a Registration Statement would require the
             disclosure of material information regarding a possible financing,
             business combination or other material transaction, which
             disclosure the Board of Directors of the Company has determined in
             its good faith judgement would be detrimental to the Company;

      then the Company may at its option direct that such request be delayed for
      a period not in excess of three (3) months from the effective date of such
      offering or, in the case of any such other activity, the date of such
      request, as the case may be, such right to delay a request to be exercised
      by the Company not more than once in any twelve month period.

(b)   If the Company delays a registration under this Section 2.4 Infineon shall
      not be treated as having made a request for purposes of the limitation in
      Section 2.3, unless and until such request is renewed following the period
      of such delay.

2.5   Participation of Company in a Required Registration

(a)   Neither the Company nor any of its securityholders shall have the right to
      include any of the Company's securities (other than Registrable Shares) in
      a Registration Statement to be filed as part of a Required Registration
      unless:

       (i)   such securities are of the same class as the Registrable Shares;

       (ii)  Infineon consents to such inclusion in writing; and

       (iii) if such Required Registration is for an underwritten offering, the
             Company or such securityholders, as applicable, agree in writing to

                                                                          Page 5

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             sell, subject to Section 2.6 their securities on the same terms and
             conditions as apply to the Registrable Shares being sold.

(b)   If any securityholders of the Company (other than Infineon in such
      capacity) register securities of the Company in a Required Registration in
      accordance with this Section 2, such holders shall pay the fees and
      expenses of their counsel and their pro rata share, on the basis of the
      respective amounts of the securities included in such registration on
      behalf of each such holder, of the Registration Expenses if the
      Registration Expenses for such registration are not paid by the Company
      for any reason.

2.6   Priority

(a)   If a Required Registration becomes a Cutback Registration, the Company
      will include in such registration to the extent of the number which the
      managing underwriter advises the Company can be sold in such offering:

       (i)   first, Registrable Shares requested to be included in such
             registration by Infineon; and

       (ii)  second, other securities of the Company proposed to be included in
             such registration, allocated among the Company and other holders of
             the Company's securities in accordance with the priorities then
             existing among the Company and the holders of such other securities
             (or as the Company and such other holders shall otherwise agree);
             and any securities so excluded shall be withdrawn from and shall
             not be included in such Required Registration.

(b)   In the event that the number of Registrable Shares requested to be
      included in a Required Registration is cutback by over 33%, such
      registration will not count as a Required Registration under this Section
      2.

3.    INCIDENTAL REGISTRATION

3.1   Whenever the Company proposes to file a Registration Statement (other than
a Registration Statement filed pursuant to Section 2 of this Agreement
registering Registrable Shares), it will, at least thirty (30) days prior to
such filing, give written notice to Infineon of its intention to do so. Upon the
written request of Infineon given within ten (10) business days after the
Company provides such notice (which request shall state the intended method of
disposition of such Registrable Shares), the Company shall use its reasonable
efforts to cause all Registrable Shares which the Company has been requested by
Infineon to register to be included in such Registration Statement to the extent
necessary to permit their sale or other disposition in accordance with the
intended method of distribution specified in the request of Infineon; provided,
however, that the Company shall have the right to postpone or withdraw any
registration effected pursuant to this Section 3 without obligation to Infineon.

3.2   In connection with any registration under this Section 3 involving an
underwriting, the Company shall not be required to include any Registrable
Shares in

                                                                          Page 6

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such registration unless Infineon accepts the terms of the underwriting as
agreed upon between the Company and the underwriters selected by it.

3.3   If any registration under this Section 3 becomes a Cutback Registration,
the Company will include in the registration only that number of Shares, if any,
which the managing underwriter believes can be sold in such offering in the
following order:

       (i)   first, the Shares the Company proposes to sell; and

       (ii)  second, the Registrable Shares requested to be included in such
             registration by Infineon.

3.4   Notwithstanding the foregoing, in the case of a Cutback Registration, no
Persons other than the Company and Infineon shall be permitted to include
securities in the offering.

3.5   The provisions of Section 3 shall not apply at any time the Company is
eligible to file and maintain the effectiveness of a Shelf Registration
Statement and is complying with its obligations under Section 2.1 with respect
to all Registrable Shares.

4.    REGISTRATION PROCEDURES

4.1   If and whenever the Company is required by this Agreement to use its
efforts to effect the registration of any of the Registrable Shares under the
Securities Act pursuant to Section 2 or Section 3, the Company will use its best
efforts to effect the registration of such Registrable Shares and to facilitate
the sale thereof in accordance with the intended method of disposition specified
by Infineon. Without limiting the foregoing, the Company in each such case shall
as expeditiously as reasonably possible:

(a)   prepare and publicly file with the Commission a Registration Statement
      with respect to such Registrable Shares and use its reasonable best
      efforts to cause that Registration Statement to become effective,
      provided, however, that, as far in advance as practical before filing such
      Registration Statement or any amendment thereto, the Company will furnish
      to Infineon copies of reasonably complete drafts of all such documents
      proposed to be filed (including exhibits), and Infineon shall have the
      opportunity to object to any information pertaining solely to Infineon
      that is contained therein and the Company will make the corrections
      reasonably requested by Infineon with respect to such information prior to
      filing any such Registration Statement or amendment;

(b)   prepare and file with the Commission any amendments and supplements to the
      Registration Statement and the prospectus included in the Registration
      Statement as may be necessary to keep the Registration Statement effective
      (i) in the case of a firm commitment underwritten Public Offering, until
      each underwriter has completed the distribution of all securities
      purchased by it, (ii) in the case of any other offering (other than a
      Shelf Registration), until the earlier of the sale of all Registrable
      Shares covered thereby or one hundred-eighty (180) days after the
      effective date thereof, and (iii) in the case

                                                                          Page 7

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      of a Shelf Registration, until the sale of all Registrable Shares covered
      thereby;

(c)   furnish to Infineon such reasonable numbers of copies of the prospectus,
      including a preliminary prospectus, in conformity with the requirements of
      the Securities Act and such other documents as Infineon may reasonably
      request in order to facilitate the public sale or other disposition of the
      Registrable Shares owned by Infineon;

(d)   use its reasonable best efforts to do any and all other acts and things
      that may be necessary or desirable to enable Infineon to consummate the
      public sale or other disposition of the Registrable Shares owned by
      Infineon in any jurisdiction provided, however, that the Company shall not
      be required in connection with this Section 4.1(d) to qualify as a foreign
      corporation, subject itself to taxation or execute a general consent to
      service of process in any jurisdiction;

(e)   if the Company has delivered preliminary or final prospectuses to Infineon
      and after having done so the prospectus is amended to comply with the
      requirements of the Securities Act or because the prospectus contains a
      material misstatement or omission, the Company shall promptly notify
      Infineon, and, if requested, Infineon shall immediately cease making
      offers of Registrable Shares and return all prospectuses, other than
      permanent file copies, to the Company. The Company shall promptly provide
      Infineon with revised prospectuses and, following receipt of the revised
      prospectuses, Infineon shall be free to resume making offers of the
      Registrable Shares;

(f)   cause management to participate in customary "roadshow" presentations;

(g)   provide promptly to Infineon upon request each document filed by the
      Company with the Commission pursuant to the requirements of Section 13 and
      Section 15 of the Exchange Act;

(h)   cooperate and assist in any filings required to be made with the National
      Association of Securities Dealers, Inc. (the NASD) and in the performance
      of any due diligence investigation by any underwriter (including any
      "qualified independent underwriter" that is required to be retained in
      accordance with the rules and regulations of the NASD), and use its
      reasonable best efforts to cause such Registration Statement to become
      effective and approved by such governmental agencies or authorities as may
      be necessary to enable Infineon to consummate the disposition of such
      Registrable Shares;

(i)   promptly notify Infineon and the underwriter or underwriters (if any):

       (i)   when such Registration Statement or any prospectus used in
             connection therewith, or any amendment or supplement thereto, has
             been filed and, with respect to such registration statement or any
             post effective amendment thereto, when the same has become
             effective;

                                                                          Page 8

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       (ii)  of any written comments from the Commission with respect to any
             filing referred to in Section 4.1(a) or of any written request by
             the Commission for amendments or supplements to such Registration
             Statement or prospectus;

       (iii) of the notification to the Company by the Commission of its
             initiation of any proceeding with respect to the issuance by the
             Commission of any stop order suspending the effectiveness of such
             Registration Statement; and

       (iv)  of the receipt by the Company of any notification with respect to
             the suspension of the qualification of any Registrable Shares for
             sale under the applicable securities or Blue Sky laws of any
             jurisdiction;

(j)   in connection with any underwritten offering, seek to obtain and, if
      requested to do so by Infineon, furnish to Infineon a copy of

       (i)   an opinion and/or disclosure letter of counsel for the Company from
             each relevant jurisdiction, dated the effective date of such
             Registration Statement (or, if such registration includes an
             underwritten Public Offering, dated the date of any closing under
             the underwriting agreement), reasonably satisfactory in form and
             substance to the underwriters, addressed to the underwriters and,
             where reasonably possible, to Infineon; and

       (ii)  a "comfort" letter, dated the effective date of such Registration
             Statement and an update thereof, dated the date of any closing
             under the underwriting agreement, signed by the independent public
             accountants who have certified the Company's financial statements
             included in such Registration Statement, addressed to the
             underwriters, and, where reasonably possible, to Infineon;

      in each case covering substantially the same matters with respect to such
      Registration Statement (and the prospectus included therein) and, in the
      case of the accountants' letter, with respect to events subsequent to the
      date of such financial statements, as are customarily covered in opinions
      and/or disclosure letters of issuer's counsel and in accountants' comfort
      letters delivered to the underwriters in underwritten Public Offerings of
      securities and, in the case of the accountants' letter, such other
      financial matters, as the underwriters may reasonably request;

(k)   otherwise use its reasonable best efforts to comply with all applicable
      rules and regulations of the Commission, and make available to its
      securityholders, as soon as reasonably practicable, an earnings statement
      covering the period of at least twelve (12) months, but not more than
      eighteen (18) months, beginning with the first full calendar month after
      the effective date of such Registration Statement, which earning statement
      shall satisfy the provisions of Section 11(a) of the Securities Act and
      Rule 158 promulgated thereunder;

                                                                          Page 9

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(l)   cooperate with the selling holders of Registrable Shares and the managing
      underwriter, underwriters or agent, if any, to facilitate the timely
      preparation and delivery of certificates representing Registrable Shares
      to be sold and not bearing any restrictive legends;

(m)   use its reasonable efforts to cooperate with the Company's transfer agent
      in settling any offering or sale of Registrable Shares, including with
      respect to the transfer of physical stock certificates into book-entry
      form in accordance with any procedures reasonably requested by Infineon or
      the managing underwriter;

(n)   use its reasonable efforts to cause all Registrable Securities of a class
      covered by the applicable Registration Statement to be listed or quoted on
      each securities exchange on which any of the Shares are then listed or
      quoted and on each inter-dealer quotation system on which any of the
      Shares are then quoted; and

(o)   make available for inspection by Infineon, any underwriter participating
      in any disposition pursuant to such Registration Statement and any
      attorney, accountant or other agent retained by Infineon or any
      underwriter (collectively, the Inspectors), all financial and other
      records, pertinent corporate documents and properties of the Company
      (collectively, the RECORDS) as shall be reasonably necessary to enable
      them to exercise their due diligence responsibility, and cause the
      Company's officers, directors and employees to supply all information
      reasonably requested by any such Inspector in connection with such
      Registration Statement, and to the extent requested by Infineon or any
      underwriter, permit the Inspectors to participate in the preparation of
      such Registration Statement and any prospectus contained therein and any
      amendment or supplement thereto.

      Records which the Company determines, in good faith, to be confidential
      and which it notifies the Inspectors are confidential shall not be
      disclosed by the Inspectors unless:

       (i)   the disclosure of such Records is necessary to avoid or correct a
             misstatement or omission in the Registration Statement;

       (ii)  the release of such Records is ordered pursuant to a subpoena or
             other order from a court of competent jurisdiction; or

       (iii) the information in such Records has been made generally available
             to the public.

      Infineon agrees that it will, upon learning that disclosure of such
      Records is sought in a court of competent jurisdiction, give notice to the
      Company and allow the Company, at the Company's expense, to undertake
      appropriate action to prevent disclosure of the Records deemed
      confidential.

4.2   The Company may require Infineon, and Infineon, as a condition to
including Registrable Shares in such registration, shall, furnish the Company
with such

                                                                         Page 10

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information and affidavits regarding Infineon and the distribution of such
securities as the Company may from time to time reasonably request in writing in
connection with such registration.

4.3   Infineon agrees that upon receipt of any notice from the Company of the
happening of any event of the kind described in Section 4.1(e) above Infineon
will forthwith discontinue Infineon's disposition of Registrable Shares pursuant
to the Registration Statement relating to such Registrable Shares until
Infineon's receipt of the copies of the supplemented or amended prospectus
contemplated by Section 4.1(e) above and, if so directed by the Company will
deliver to the Company (at the Company's expense) all copies, other than
permanent file copies, then in Infineon's possession of the prospectus relating
to such Registrable Shares current at the time of receipt of such notice. In the
event the Company shall give any such notice, the period referred to in Section
4.1(b) above shall be extended by a number of days equal to the number of days
during the period from and including the giving of notice pursuant to Section
4.1(e) and to and including the date when each holder of any Registrable Shares
covered by such registration statement shall receive the copies of the
supplemented or amended prospectus contemplated by Section 4.1(e).

5.    UNDERWRITTEN OFFERINGS

5.1   Underwritten offerings pursuant to Section 2

(a)   In the case of any underwritten Public Offering being effected pursuant to
      Section 2, the managing underwriter and any other underwriter or
      underwriters with respect to such offering shall be selected, after
      consultation with the Company, by Infineon with the consent of the
      Company, which consent shall not be unreasonably withheld.

(b)   The Company shall enter into an underwriting agreement in customary form
      with such underwriter or underwriters, which shall include, among other
      provisions, indemnities to the effect and to the extent provided in
      Section 7.

(c)   Infineon shall be a party to such underwriting agreement and may, at its
      option, require that any or all of the representations and warranties by,
      and the other agreements on the part of, the Company to and for the
      benefit of such underwriters also be made to and for its benefit and that
      any or all of the conditions precedent to the obligations of such
      underwriters under such underwriting agreement also be conditions
      precedent to its obligations. Infineon shall not be required to make any
      representations or warranties to or agreements with the Company or the
      underwriters other than representations, warranties or agreements
      regarding Infineon and its ownership of the securities being registered on
      its behalf and Infineon's intended method of distribution and any other
      representation required by law. Infineon may not participate in such
      underwritten offering unless Infineon agrees to sell its Registrable
      Shares on the basis provided in such underwriting agreement and completes
      and executes all questionnaires, powers of attorney, indemnities and other
      documents reasonably required under the terms of such underwriting
      agreement.

                                                                         Page 11

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(d)   Subject to compliance with the provisions of Section 6 (with respect to
      withdrawals of registration at the request of Infineon), if Infineon
      disapproves of the terms of an underwriting, Infineon may elect to
      withdraw therefrom and from such registration and elect not to have such
      registration counted as a registration requested by it for purposes of the
      limitation in Section 2.3 by notice to the Company and the managing
      underwriter.

5.2   Underwritten offerings pursuant to Section 3

(a)   If the Company at any time proposes to register any of its securities
      pursuant to Section 3 and such securities are to be distributed by or
      through one or more underwriters, the Company will, subject to the
      provisions of Section 3.2, Section 3.3 and Section 3.4 use its best
      efforts, if requested by Infineon, to arrange for such underwriters to
      include the Registrable Shares to be offered and sold by Infineon among
      the securities to be distributed by such underwriters, and Infineon shall
      be obligated to sell their Registrable Shares in such registration
      pursuant to Section 3 through such underwriters on the same terms and
      conditions as apply to the other Company securities to be sold by such
      underwriters in connection with such registration pursuant to Section 3.

(b)   Infineon shall be a party to the underwriting agreement between the
      Company and such underwriter or underwriters and may, at its option,
      require that any or all of the representations and warranties by, and the
      other agreements on the part of, the Company to and for the benefit of
      such underwriters also be made to and for its benefit and that any or all
      of the conditions precedent to the obligations of such underwriters under
      such underwriting agreement also be conditions precedent to its
      obligations. Infineon shall not be required to make any representations or
      warranties to or agreements with the Company or the underwriters other
      than representations, warranties or agreements regarding Infineon and its
      ownership of the securities being registered on its behalf and Infineon's
      intended method of distribution and any other representation required by
      law. Infineon may not participate in such underwritten offering unless
      Infineon agrees to sell its Registrable Shares on the basis provided in
      such underwriting agreement and completes and executes all questionnaires,
      powers of attorney, indemnities and other documents reasonably required
      under the terms of such underwriting agreement.

(c)   If Infineon disapproves of the terms of an underwriting, Infineon may
      elect to withdraw therefrom and from such registration by notice to the
      Company and the managing underwriter.

6.    ALLOCATION OF EXPENSES

6.1   The Company will pay all Registration Expenses of all registrations under
this Agreement provided, however, that if a registration under Section 2 is
withdrawn at the request of Infineon after a Registration Statement with respect
thereto has been publicly filed with the Commission (other than as a result of
information concerning the business, results of operations or financial
condition of the Company which is made known to Infineon after the date on which
such registration was requested) and if Infineon elects not to have such
registration counted as a registration effected by the

                                                                         Page 12

<PAGE>

Company or requested by Infineon under Section 2.2, Infineon shall pay the
Registration Expenses of such registration pro rata in accordance with the
number of Registrable Shares included in such registration.

6.2   For purposes of this Section 6, the term REGISTRATION EXPENSES shall mean
all expenses incurred by the Company in complying with this Agreement,
including, without limitation, all NASD expenses, all registration and filing
fees, exchange listing fees, printing expenses, road show expenses, fees and
expenses of any consultants or experts retained by the Company in connection
with such registration, fees and expenses of counsel for the Company and the
reasonable fees and expenses of Infineon's counsel, state Blue Sky fees and
expenses (if any), fees and expenses of the Company's independent auditors
(including the expenses of any comfort letters or costs associated with the
delivery by independent certified public accountants of a comfort letter or
comfort letters requested pursuant to Section 4.1(j)(ii) hereof) but excluding
underwriting discounts and selling commissions.

7.    INDEMNIFICATION AND CONTRIBUTION

7.1   Company Indemnification

(a)   The Company will indemnify and hold harmless each underwriter of
      Registrable Shares, each other person, if any, who controls such
      underwriter within the meaning of the Securities Act or the Exchange Act,
      and Infineon, including each of the officers and directors of such
      underwriters, such controlling persons, and Infineon, against any losses,
      claims, damages or liabilities, joint or several, to which such
      underwriter, such controlling person or Infineon may become subject under
      the Securities Act, the Exchange Act, state securities or Blue Sky laws or
      otherwise, insofar as such losses, claims, damages or liabilities (or
      actions in respect thereof) arise out of or are based upon any untrue
      statement or alleged untrue statement of any material fact contained in
      any Registration Statement under which such Registrable Shares were
      registered under the Securities Act, any preliminary prospectus or final
      prospectus contained in the Registration Statement, or any amendment or
      supplement to such Registration Statement, or arise out of or are based
      upon the omission or alleged omission to state a material fact required to
      be stated therein or necessary to make the statements therein not
      misleading; and the Company will reimburse such underwriter, such
      controlling person and Infineon for any legal or any other expenses
      reasonably incurred by such underwriter, such controlling person or
      Infineon in connection with investigating or defending any such loss,
      claim, damage, liability or action; provided, however, that the Company
      will not be liable in any such case to the extent that any such loss,
      claim, damage or liability arises out of or is based upon any untrue
      statement or omission made in such Registration Statement, preliminary
      prospectus or final prospectus, or any such amendment or supplement, in
      reliance upon and in conformity with information furnished to the Company,
      in writing, by or on behalf of such underwriter, such controlling person
      or Infineon specifically for use in the preparation thereof.

                                                                         Page 13

<PAGE>

(b)   Such indemnity shall remain in full force and effect regardless of any
      investigation made by or on behalf of Infineon, such underwriter or any
      such director, officer or controlling person, and shall survive the
      transfer of such Registrable Shares by Infineon, such underwriter or
      controlling person. Such indemnity shall not apply to amounts paid in
      settlement of any loss, claim, damage, liability or action if such
      settlement is effected without the consent of the Company.

7.2   Seller Indemnification

(a)   Infineon will indemnify and hold harmless the Company, each underwriter
      (if any) and each person (if any) who controls the Company or any such
      underwriter within the meaning of the Securities Act or the Exchange Act,
      and each of the directors and officers of the Company, each such
      underwriter (if any) or controlling person (if any), against any losses,
      claims, damages or liabilities, joint or several, to which the Company,
      such underwriter, controlling person or director or officer may become
      subject under the Securities Act, the Exchange Act, state securities or
      Blue Sky laws or otherwise, insofar as such losses, claims, damages or
      liabilities (or actions in respect thereof) arise out of or are based upon
      any untrue statement or alleged untrue statement of a material fact
      contained in any Registration Statement under which such Registrable
      Shares were registered under the Securities Act, any preliminary
      prospectus or final prospectus contained in the Registration Statement, or
      any amendment or supplement to the Registration Statement, or arise out of
      or are based upon any omission or alleged omission to state a material
      fact required to be stated therein or necessary to make the statements
      therein not misleading, if the statement or omission was made in reliance
      upon and in conformity with information relating to Infineon furnished in
      writing to the Company by or on behalf of Infineon specifically for use in
      connection with the preparation of such Registration Statement,
      prospectus, amendment or supplement; provided, however, that the
      obligations of Infineon hereunder shall be limited to an amount equal to
      the proceeds to Infineon from Registrable Shares sold in connection with
      such registration.

(b)   Such indemnity shall remain in full force and effect regardless of any
      investigation made by or on behalf of the Company or any such director,
      officer or controlling person, and shall survive the transfer of such
      Shares by Infineon.

7.3   Procedure

(a)   Each party entitled to indemnification under this Section 7 (the
      INDEMNIFIED PARTY) shall give notice to the party required to provide
      indemnification (the INDEMNIFYING PARTY) promptly after such Indemnified
      Party has actual knowledge of any claim as to which indemnity may be
      sought, and shall permit the Indemnifying Party to assume the defence of
      any such claim or any litigation resulting therefrom; provided, however,
      that counsel for the Indemnifying Party, who shall conduct the defence of
      such claim or litigation, shall be approved by the Indemnified Party
      (whose approval shall not be

                                                                         Page 14

<PAGE>

      unreasonably withheld or delayed) and; provided further, that the failure
      of any Indemnified Party to give notice as provided herein shall not
      relieve the Indemnifying Party of its obligations under this Section 7,
      except to the extent that the Indemnifying Party is actually prejudiced by
      such failure to give notice.

(b)   The Indemnified Party may participate in such defence at such party's
      expense; provided, however, that the Indemnifying Party shall pay such
      expense if representation of such Indemnified Party by the counsel
      retained by the Indemnifying Party would be inappropriate due to actual or
      potential conflicts of interests between the Indemnified Party and the
      Indemnifying Party.

(c)   No Indemnifying Party, in the defence of any such claim or litigation to
      which an Indemnified Party is or could have been a party and with respect
      to which indemnity or contribution may be or could have been sought
      hereunder shall, except with the consent of such Indemnified Party,
      consent to entry of any judgement or enter into any settlement which does
      not include as an unconditional term thereof the giving by the claimant or
      plaintiff to such Indemnified Party of a release from all liability in
      respect of such claim or litigation. No Indemnified Party shall consent to
      entry of any judgement or settle any such claim or litigation without the
      prior written consent of the Indemnifying Party.

7.4   In order to provide for just and equitable contribution to joint liability
under the Securities Act in any case in which either

       (i)   Infineon exercises rights under this Agreement or any controlling
             person of Infineon makes a claim for indemnification pursuant to
             this Section 7, but it is judicially determined (by the entry of a
             final judgement or decree by a court of competent jurisdiction and
             the expiration of time to appeal or the denial of the last right of
             appeal) that such indemnification may not be enforced in such case
             notwithstanding the fact that this Section 7 provides for
             indemnification in such case; or

       (ii)  contribution under the Securities Act may be required on the part
             of Infineon or any such controlling person in circumstances for
             which indemnification is provided under this Section 7;

      then, in each such case, the Company and Infineon will contribute to the
      aggregate losses, claims, damages or liabilities to which they may be
      subject (after contribution from others) in such proportions so that
      Infineon is responsible for the portion represented by the percentage that
      the public offering price of its Registrable Shares offered by the
      Registration Statement bears to the public offering price of all
      securities offered by such Registration Statement, and the Company is
      responsible for the remaining portion;

      provided, however, that, in any such case

                                                                         Page 15

<PAGE>

       (i)   Infineon will not be required to contribute any amount in excess of
             the proceeds to it of all Registrable Shares sold by it pursuant to
             such Registration Statement; and

       (ii)  no person or entity guilty of fraudulent misrepresentation, within
             the meaning of Section 11(f) of the Securities Act, shall be
             entitled to contribution from any person or entity who is not
             guilty of such fraudulent misrepresentation.

8.    STAND-OFF AGREEMENT

8.1   Infineon, if requested by the managing underwriter (if any) of an offering
by the Company of Shares pursuant to a Registration Statement, shall agree not
to sell publicly or otherwise transfer or dispose of any Registrable Shares or
other securities of the Company (including a sale under Rule 144) held by
Infineon during the fourteen (14) days prior to and for a specified period of
time (not to exceed ninety (90) days) following the effective date of such
Registration Statement, except as part of such Registration Statement, whether
or not Infineon participates in such registration; provided, however, that all
other holders of unregistered Shares holding not less than 1% (including Shares
issuable upon the conversion of convertible securities, or upon the exercise of
options, warrants or rights) and all officers and directors of the Company enter
into similar agreements.

8.2   Unless Infineon otherwise agrees, the Company agrees (i) not to effect any
public sale or distribution of its equity securities, or any securities
convertible into or exchangeable or exercisable for such securities, during the
fourteen (14) days prior to and the ninety (90) days after the effective date of
the registration statement filed in connection with an underwritten offering
made pursuant to a Required Registration (or for such shorter period of time as
is sufficient and appropriate, in the opinion of the managing underwriter (if
any), in order to complete the sale and distribution of the securities included
in such registration), except as part of such underwritten registration and
except pursuant to registrations on Form S-4, Form F-4 or Form S-8 promulgated
by the Commission or any successor or similar forms thereto, and (ii) use its
reasonable efforts to cause each holder of its equity securities, or of any
securities convertible into or exchangeable or exercisable for such securities,
in each case purchased from the Company at any time after the date of this
Agreement (other than in a Public Offering), to agree, to the extent permitted
by law, not to effect any such public sale or distribution of such securities
(including a sale under Rule 144), during such period, except as part of such
underwritten registration.

9.    LIMITATIONS ON SUBSEQUENT REGISTRATION RIGHTS

9.1   The Company shall not, without the prior written consent of Infineon
(which consent shall not be unreasonably withheld), enter into any agreement
(other than this Agreement) (i) with any holder or prospective holder of any
securities of the Company which would allow such holder or prospective holder (a
NEW CONCERNED SHAREHOLDER) (a) to make a demand registration or (b) to request
an Incidental Registration, or (ii) that would otherwise conflict or interfere
with the rights of Infineon under this Agreement.

                                                                         Page 16

<PAGE>

10.   RULE 144 REQUIREMENTS

10.1  The Company agrees to:

(a)   file with the Commission in a timely manner all reports and other
      documents required of the Company under the Securities Act and the
      Exchange Act (at any time after it has become subject to such reporting
      requirements); and

(b)   furnish to any holder of Registrable Shares upon request a written
      statement by the Company as to its compliance with the requirements of
      Rule 144(c) and the reporting requirements of the Securities Act and the
      Exchange Act (at any time after it has become subject to such reporting
      requirements).

11.   MERGERS, ETC

11.1  The Company shall not, directly or indirectly, enter into any merger,
consolidation or reorganization in which the Company shall not be the surviving
corporation unless the proposed surviving corporation shall, prior to such
merger, consolidation or reorganization, agree in writing to assume the
obligations of the Company under this Agreement, and for that purpose references
hereunder to Registrable Shares shall be deemed to be references to the
securities which Infineon would be entitled to receive in exchange for
Registrable Shares under any such merger, consolidation or reorganization.

11.2  The provisions of Section 11.1 shall not apply in the event of any merger,
consolidation or reorganization in which the Company is not the surviving
corporation if Infineon is entitled to receive in exchange for its Registrable
Shares consideration consisting solely of

       (i)   cash;

       (ii)  securities of the acquiring corporation which may be immediately
             sold to the public without registration under the Securities Act;
             or

       (iii) securities of the acquiring corporation which the acquiring
             corporation has agreed to register within five days of completion
             of the transaction for resale to the public pursuant to the
             Securities Act.

12.   STOCKHOLDER AGREEMENT

12.1  Notwithstanding anything to the contrary set forth in this Agreement, the
parties acknowledge and agree that the transfer of Shares by Infineon shall be
subject to the terms of the Stockholder Agreement entered into by Infineon and
the Company as of the date hereof.

13.   TERMINATION

13.1  This Agreement shall terminate upon the earlier of (a) the date as of
which all of the Registrable Shares have been sold pursuant to a Registration
Statement (but in no event prior to the applicable period referred to in Section
4(3) of the Securities Act

                                                                         Page 17

<PAGE>

and Rule 174 thereunder); (b) the date on which all the holders are permitted to
sell all their Registrable Shares under Rule 144(k) under the Securities Act (or
any similar provision then in force permitting the sale of restricted securities
without limitation on the amount of securities sold or the manner of sale); or
(c) the valid termination prior to Closing of the Sale and Purchase Agreement.
In the event of the termination of this Agreement pursuant to Section 13.1(c),
this Agreement shall forthwith become void, and there shall be no liability on
the part of any party hereto.

14.   TRANSFERS OF RIGHTS

14.1  This Agreement, and the rights and obligations of Infineon hereunder, may
be assigned by Infineon to any person or entity to which Shares are transferred
by Infineon in accordance with any contractual limitations on a transfer of
Shares and thereafter shall for all purposes of this Agreement be treated as
Infineon would be hereunder; provided, however, that the transferee provides
written notice of such assignment to the Company.

15.   NOTICES

15.1  All notices, requests, consents, and other communications under this
Agreement shall be in writing and shall be delivered by facsimile transmission
to the parties at the following Facsimile numbers or by hand or mailed by first
class certified or registered mail, return receipt requested, postage prepaid to
the parties at the following addresses:

If to Infineon, to:

      Party:                                INFINEON TECHNOLOGIES AG

      Address:                              St.-Martin-Strasse 53
                                            D-81541 Munich
                                            Federal Republic of Germany

      Facsimile No:                         +49 89 234 24 108

      Attn. of:                             Legal Department

      With a copy to:                       Freshfields Bruckhaus Deringer

      Address:                              Prannerstra(beta)e 10
                                            80333 Munchen
                                            Germany

      Facsimile No.:                        +49 89 20 70 21 00

      Attn. of:                             Dr. Ferdinand Fromholzer

                                                                         Page 18

<PAGE>

If to the Company, to:

      Party:                                Finisar Corporation

      Address:                              1308 Moffett Park Drive
                                            Sunnyvale, CA 94089

      Facsimile No:                         (408) 541-9579

      Attn. of:                             Chief Executive Officer

      With a copy to:                       DLA Piper Rudnick Gray Cary LLP

      Address:                              2000 University Avenue
                                            East Palo Alto, CA 94303-2248

      Facsimile No.:                        (650) 833-2001

      Attn. of:                             Dennis C. Sullivan, Esq.

15.2  Notices provided in accordance with this Section 15 shall be deemed
delivered upon personal delivery or two business days after deposit in the mail.

16.   ENTIRE AGREEMENT

16.1  This Agreement embodies the entire agreement and understanding between the
parties hereto with respect to the subject matter hereof and supersedes all
prior agreements and understandings relating to such subject matter.

17.   AMENDMENTS AND WAIVERS

17.1  Any term of this Agreement may be amended and the observance of any term
of this Agreement may be waived (either generally or in a particular instance
and either retroactively or prospectively), with the written consent of the
Company and Infineon.

17.2  No waivers of or exceptions to any term, condition or provision of this
Agreement, in any one or more instances, shall be deemed to be, or construed as,
a further or continuing waiver of any such term, condition or provision.

18.   COUNTERPARTS

18.1  This Agreement may be executed in one or more counterparts, each of which
shall be deemed to be an original, but all of which shall be one and the same
document.

                                                                         Page 19

<PAGE>

19.   SEVERABILITY

19.1  The invalidity or unenforceability of any provision of this Agreement
shall not affect the validity or enforceability of any other provision of this
Agreement.

20.   GOVERNING LAW

20.1  This Agreement shall be construed in accordance with, and this Agreement
and all matters arising out of or relating in any way whatsoever (whether in
contract, tort or otherwise) to this Agreement shall be governed by, the law of
the State of New York.

21.   ARBITRATION

21.1  All disputes arising in connection with this Agreement or its validity
shall be finally settled by three arbitrators in accordance with the Arbitration
Rules of the German Institution of Arbitration e.V. (DIS) without recourse to
the ordinary courts of law. The venue of the arbitration shall be Munich. The
language of the arbitral proceedings shall be English.

21.2  Without limiting the foregoing, each party agrees that service of process
on such party as provided in Section 15 shall be deemed effective service of
process on such person.

22.   HEADINGS

22.1  The headings in this Agreement are for convenience of reference only and
shall not control or affect the meaning or construction of any provisions of
this Agreement.

                                                                         Page 20

<PAGE>

IN WITNESS WHEREOF, the Company and Infineon have caused this Agreement to be
executed as of the date first written above by their respective officers
thereunto duly authorized.

                                      FINISAR CORPORATION

                                      BY: /s/ S.K. Workman
                                          --------------------------------------
                                      NAME: S.K. Workman
                                      TITLE: CFO

                                      INFINEON TECHNOLOGIES AG

                                      BY: /s/ Arno Paetzold  /s/ Stefan Sommer
                                          ------------------ -------------------
                                      NAME: Arno Paetzold    Stefan Sommer
                                      TITLE: SD M&A          Corp. Legal Counsel

                                                                         Page 22