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                                                                    EXHIBIT 10.6

                                 LUMINENT, INC.

                             STOCK OPTION AGREEMENT

       This Stock Option Agreement ("Agreement") is made effective as of the
____ day of July, 2000 by and between Luminent, Inc. (the "Company") and Eric I.
Blachno (the "Optionee").

                                    RECITALS

       WHEREAS, the Company has retained Optionee as its Vice President of
Finance and Chief Financial Officer;

       WHEREAS, the Company believes it to be in its best interest to, and has
agreed to grant Optionee an option to purchase shares of Common Stock of the
Company;

       WHEREAS, Optionee, in consideration of, among other things, the grant of
this option, has accepted the Company's offer of employment on the terms set
forth in that certain Letter Agreement dated July __, 2000 from the Company and
MRV Communications, Inc. to Optionee (the "Letter Agreement").


                                    AGREEMENT

       NOW, THEREFORE, in consideration of the foregoing and of the mutual
covenants set forth herein and other good and valuable consideration, the
parties hereto agree as follows:

       1. The Option(s). The Optionee may, at his option, purchase all or any
part of an aggregate of _______ shares of Common Stock (the "Optioned Shares"),
at the price of $____ per share (the "Option Price"), on the terms and
conditions set forth herein.

       2. Exercise Dates and Exercise. The Option(s) shall be exercisable as to
all or any portion of the specified number of Optioned Shares at any time or
from time to time on and after the "First" dates set forth below (when such
Option(s) shall respectively accrue and become vested), and on or before the
"Last" dates (the Option Expiration Date) set forth below:

  Exercise Dates

    Number of Shares

First
Last

[25%]

July __, 2001
July __, 2010



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[25%]

July __, 2002
July __, 2010

[25%]

July __, 2003
July __, 2010

[25%]

July __, 2004
July __, 2010

       Optionee acknowledges that he understands he has no right whatsoever to
exercise the Option(s) granted hereunder with respect to any Optioned Shares
covered by any installment until such installment accrues and vests as provided
above and that all unaccrued installments shall cease to accrue on the date of
termination of Optionee's employment with the Company, except as may otherwise
be provided in the Letter Agreement. Optionee further understands that the
Option(s) granted hereunder shall expire and become unexercisable as provided in
Section 3 below.

       This Option shall be deemed exercised as to the shares to be purchased
when written notice of such exercise has been given to the Company at its
principal business office by the Optionee with respect to the Common Stock to be
purchased. Such notice shall be accompanied or preceded by full payment in cash
or cash equivalents of the Option Price or by a notification in customary form
of the use by Optionee of a broker-assisted cashless exercise procedure.

       3. Early Exercise and/or Termination. Notwithstanding the provisions of
Section 2, this Option shall be exercisable after a Change of Control or Sale of
the Company (as such terms are defined in the Letter Agreement) or a termination
of Optionee's employment with the Company only at the times, to the extent, and
on the terms and conditions set forth in the Letter Agreement.

       4. Representations and Warranties; Registration of Shares Underlying
Options. Optionee represents and warrants to the Company as follows:

              (a) He understands that neither the Option evidenced by this
       Agreement nor the Optioned Shares have been registered under the
       Securities Act of 1933, as amended (the "Act"), and are not freely
       tradable. The securities must be held indefinitely unless either a
       registration statement with respect to the securities is filed and
       declared effective under the Act or an exemption from the registration
       requirement of the Act is available.



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              (b) He understands that the Company has no obligation to register
       any or all the Optioned Shares under the Act for distribution, except as
       otherwise provided in the Letter Agreement.

              (c) He acknowledges that as a condition to the exercise of any
       portion of this Option, the Company may require the Optionee to make any
       representation and/or warranty to the Company as may, in the reasonable
       judgment of counsel to the Company, be required under any applicable law
       or regulation, including but not limited to a representation and warranty
       that the Optioned Shares are being acquired only for investment and
       without any present intention to sell or distribute such shares if, in
       the opinion of counsel for the Company, such a representation is required
       under the Act or any other applicable law, regulation or rule of any
       governmental agency; provided, however, that in accordance with the
       provisions of the Letter Agreement, the Company shall use its best
       efforts (including without limitation the timely filing of a registration
       statement under the Act and any registration or qualification required by
       applicable state securities laws) to achieve compliance with the Act or
       such other law, regulation or rule, as applicable, without requiring any
       such representation or warranty by Optionee. The Option and the Optioned
       Shares are being acquired for investment for Optionee's own account and
       not with a view to sale or resale, distribution (as that term is defined
       in the Act), or transfer, or to offers in connection therewith.

              (d) He is an "accredited investor" as such term is defined in Rule
       501(a) of Regulation D under the Act, and has such knowledge and
       experience in financial and business matters as to be able to evaluate
       the merits and risks of the acquisition of the securities, and, having
       had access to, or having been furnished with, all such information as he
       considers necessary, has concluded that he is able to bear those risks.

              (e) He acknowledges that the Company will, to the extent
       determined by the Company's legal counsel to be required by applicable
       law, affix a legend in substantially the following form to the
       certificates evidencing the Optioned Shares:

              The securities represented by this certificate have not been
              registered under the Securities Act of 1933, as amended, and may
              not be sold, pledged, hypothecated, donated, or otherwise
              transferred, whether or not for consideration, unless either the
              securities have been registered under said Act or an exemption
              from such registration requirement is available. If the Shares are
              to be sold or transferred pursuant to an exemption from the
              registration requirement, the Company may require a written
              opinion of counsel, reasonably satisfactory to counsel for
              Company, to the effect that registration is not required.

       The Company shall without charge offer to substitute an unlegended
       certificate for any legended certificate promptly after the Optioned
       Shares represented by such legended certificate first become eligible for
       sale by Optionee pursuant to Rule 144(k) (or any successor provision)
       under the Act.



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              (f) Prior to any proposed sale, pledge, hypothecation, gift, or
       other transfer, for value or otherwise, of any or all of the Option
       evidenced by this Agreement or the Optioned Shares or of any interest
       therein other than a sale in compliance with the requirements of Rule 144
       under the Act (hereinafter, a "Transfer"), Optionee shall give written
       notice to the Company describing the Transfer. Optionee shall not effect
       any Transfer unless and until (a) the Company receives an opinion of
       Optionee's counsel, in form and substance reasonably acceptable to
       counsel for the Company, that the Transfer may be effected without
       registration under the Act and without registration or qualification
       under applicable state securities laws, (provided, however, that no such
       opinion shall be required in connection with any bona fide gift of the
       Optioned Shares to a member of Optionee's immediate family or a
       charitable or educational institution), and (b) satisfaction of such
       other conditions as may be reasonably required by counsel to the Company
       in order to assure compliance with the Act and with applicable state
       securities laws.

       5. No Enlargement of Rights. Nothing in this Agreement shall be construed
to confer upon the Optionee any right to continued engagement by the Company or
to restrict in any way the right of the Company to terminate its arrangement
with Optionee subject to the terms of the Letter Agreement or any other
applicable agreement between them.

       6. Withholding of Taxes. Optionee authorizes the Company to withhold, in
accordance with any applicable law, from any amounts payable to Optionee any
taxes required to be withheld by federal, state or local law as a result of the
grant of the Option(s) or the issuance of stock pursuant to the exercise of such
Option(s).

       7. Laws Applicable to Construction; Choice of Jurisdiction and Forum.
This Agreement shall be construed and enforced in accordance with the laws of
the State of California, without reference to the conflict of laws provisions of
any jurisdiction. The parties hereby submit to the exclusive jurisdiction of and
venue in the state courts of the State of California or the federal courts
located within or the Central District of California with respect to any
disputes concerning the subject matter of this agreement.

       8. Agreement Binding on Successors. The terms of this Agreement shall be
binding upon the executors, administrators, heirs, successors, transferees and
assignees of the Optionee. The terms of this Agreement shall be binding upon the
successors of the Company.

       9. Necessary Acts. The Optionee agrees to perform all acts and execute
and deliver any documents that may be reasonably necessary to carry out the
provisions of this Agreement, including but not limited to all acts and
documents related to compliance with federal and/or state securities laws;
provided, however, that the Company shall use its best efforts to achieve
compliance with such securities laws without any action by Optionee.

       10. Counterparts. For convenience this Agreement may be executed in any
number of identical counterparts, each of which shall be deemed a complete
original in itself and may be introduced in evidence or used for any other
purpose without the production of any other counterparts.



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       11. Invalid Provisions. In the event that any provision of this Agreement
is found to be invalid or otherwise unenforceable under any applicable law, such
invalidity or unenforceability shall not be construed as rendering any other
provisions contained herein invalid or unenforceable, and all such other
provisions shall be given full force and effect to the same extent as though the
invalid and unenforceable provision was not contained herein.

       12. Adjustments upon Changes in Capitalization. If the outstanding shares
of Common Stock of the Company are increased, decreased, changed into or
exchanged for a different number or kind of shares of the Company through
reorganization, recapitalization, reclassification, stock dividend, stock split
or reverse stock split or other similar event, then an equitable and
proportionate adjustment shall be made in the number or kind of shares which may
be issued upon exercise of the Options granted under this Agreement.

       13. Options Not Transferable. This Option may be exercised during the
lifetime of the Optionee only by the Optionee. The Optionee's rights and
interests under this Agreement and in and to the Option may not be sold,
pledged, hypothecated, assigned, encumbered, gifted or otherwise transferred in
any manner, either voluntarily or involuntarily by operation of law, except by
will or the laws of descent or distribution.



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       IN WITNESS WHEREOF, the Company and the Optionee have executed this
Agreement effective as of the date first written hereinabove.



The Company

LUMINENT, INC


By
  -------------------------------------
Name:
     ----------------------------------
Its:
    -----------------------------------


Luminent, Inc.
20550 Nordhoff Street
Chatsworth, California 91311


Optionee

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        Eric I. Blachno

Eric Blachno

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Social Security No.
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