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                                                                   Exhibit 10.51
                              EMPLOYMENT AGREEMENT
                              --------------------

     EMPLOYMENT AGREEMENT dated as of February 2nd, 2000 (the "Execution Date")
by and between PixTech, Inc., a Delaware corporation (the "Company") with its
principal offices at 2700 Augustine Drive, Suite 255, Santa Clara, CA 95954, and
Dieter Mezger (the "Executive").

     WHEREAS, the Executive served as President of the Company between April 1,
1998 and January 15, 1999, and has served as President and Chief Executive
officer of the Company since January 15, 1999, and the Company and the Executive
wish to describe this relationship in a written Agreement embodying the terms of
such employment (the "Agreement"); and

     WHEREAS, the Executive desires to enter into such an Agreement;

     NOW, THEREFORE, in consideration of the premises, and the mutual covenants
and agreements contained herein and for other good and valuable consideration,
the receipt, adequacy and sufficiency of which are hereby acknowledged, the
parties hereby agree as follows:

     1.  Term of Employment. The Company hereby acknowledges and agrees that the
Executive is employed by the Company, and the Executive hereby acknowledges and
agrees that he has been employed by the Company, upon the terms and subject to
the conditions set forth in this Agreement, for a period which commenced on
April 1, 1998 (the "Effective Date") and shall continue until terminated in
accordance with the provisions of Section 5 (the "Employment Term").

     2.  Title; Duties. The Executive has served as President of the Company
between April 1, 1998 and January 15, 1999, and has served as President and
Chief Executive officer of the Company beginning on January 15, 1999 and during
the Employment Term shall continue to serve as the President and Chief Executive
Officer of the Company. In such position, the Executive has such duties and
authority as designated from time to time by the Board of Directors of the
Company (the "Board") or its designee. The Executive hereby agrees to undertake
the duties and responsibilities inherent in such position and such other duties
and responsibilities as the Board or its designee shall from time to time
reasonably assign to him.

     3.  No Conflict.  During the Employment Term, the Executive has devoted and
shall continue to devote substantially all of his business time and best efforts
to the performance of his duties hereunder and shall not, directly or
indirectly, engage in any other business, profession or occupation for
compensation or otherwise which would conflict with the rendition of such duties
without the prior written consent of the Board, which consent shall not
unreasonably be withheld, delayed or conditioned.  The Executive represents and
warrants that Schedule A attached hereto states all current business
relationships, including, but not limited to, consulting agreements,
confidentiality agreements and non-competition agreements that the Executive is
currently a party to.

     4.  Compensation and Benefits.
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4.1  Base Salary. During the Employment Term, the Company shall pay the
     Executive for his services hereunder a base salary (the "Base Salary") at
     the initial annual rate of $180,000, payable in regular

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     installments in accordance with the Company's usual payment practices and
     subject to annual review and adjustment by the Compensation Committee of
     the Board in its sole discretion.

4.2  Acceleration of Stock Options. Upon a Change of Control (as hereinafter
     defined), all options to purchase equity securities of the Company which
     have been or shall be granted to the Executive shall immediately accelerate
     and vest. The terms of this Section 4.2 shall amend and supersede the terms
     of any existing stock option agreement to which the Executive is a party
     with the Company.

     For purposes of this Section 4.2, "Common Stock" shall mean the Company's
common stock, $0.01 par value per share, and any security of the Company
convertible into common stock, on an as converted basis.

     For purposes of this Section 4.2, the occurrence of any one of the
following shall be deemed a "Change of Control":

(i)   the acquisition by United Microelectronics Corporation, its subsidiaries
      or affiliates (collectively, "UMC") of any amount of the Company's Common
      Stock so that the aggregate shares held or controlled by UMC constitute
      all or substantially all of the Company's Common Stock, or the acquisition
      by UMC or all or substantially all of the assets of the Company;

(ii)  the acquisition by any "person" (as such term is defined in Section
      3(a)(9) of the Securities Exchange Act of 1934), other than UMC, of any
      amount of the Company's Common Stock so that it holds or controls fifty
      percent (50%) or more of the Company's Common Stock, or the sale of all or
      substantially all of the assets of the Company to a person;

(iii) a merger, consolidation or similar transaction after which fifty percent
      (50%) or more of the voting stock of the surviving corporation is held by
      persons who where not stockholders of the Company immediately prior to
      such merger or combination; or

(iv)  a merger, consolidation or similar transaction after which fifty percent
      (50%) or more of the board of directors of the surviving corporation were
      not members of the Board prior to such merger or combination.

4.3  Bonus. As further compensation for his services hereunder, the Company may,
     from time to time and in accordance with the Company's policies, pay the
     Executive a bonus.

4.4  Executive Benefits. During the Employment Term and subject to any
     contributions therefor generally required of senior executives of the
     Company, the Executive has been and shall continue to be entitled to
     receive such employee benefits (including fringe benefits, 401(k) plan
     participation, and life, health, accident and disability insurance, if any)
     which the Company may, in its sole and absolute discretion, make available
     generally to its senior executives, or for personnel similarly situated;
     provided, however, that it is hereby acknowledged and agreed that any such
     employee benefit plans may be altered, modified or terminated by the
     Company at any time in its sole discretion without recourse by the
     Executive.

4.5  Vacation. The Executive has been and shall continue to be entitled to 3
     weeks (15 business days) of paid vacation per annum during the Employment
     Term, to accrue in accordance with the Company's

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     policy and to be taken at such time or times as shall be mutually
     convenient for the Company and the Executive. Unused vacation time will be
     allocated pursuant to the Company's existing policies and practices.

4.6  Business Expenses and Perquisites. The Executive has been and shall
     continue to be entitled to reimbursement by the Company during the
     Employment Term for reasonable travel, entertainment and other business
     expenses incurred by the Executive in the performance of his duties
     hereunder in accordance with such policies as the Company may from time to
     time have in effect.

4.7  Automobile. The Executive has been and shall continue to be given use of an
     automobile or be entitled to reimbursement by the Company during the
     Employment Term for reasonable expenses incurred by the Executive in
     maintaining an automobile for the Executive's use.

4.8  Indemnification. The Company shall, to the fullest extent permitted by the
     General Corporation Law of the State of Delaware, as amended from time to
     time and in accordance with the Company's Certificate of Incorporation, as
     amended from time to time, and By-laws, as amended from time to time,
     indemnify the Executive if the Executive is a party or is threatened to be
     made a party to any threatened, pending or completed action, suit or
     proceeding, whether civil, criminal, administrative or investigative, by
     reason of the fact that he is or was an officer of the Company, against
     expenses (including attorney's fees), judgments, fines and amounts paid in
     settlement actually and reasonably incurred by him or on his behalf in
     connection with such action, suit or proceeding and any appeal therefrom.
     In addition, the Executive shall be covered by the Company's standard
     director and officer insurance.

     5.  Termination.
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5.1  Without Cause by the Company. The Executive's employment hereunder may be
     terminated by the Company at any time without Cause upon not less than
     thirty (30) days prior written notice from the Company to the Executive
     (the date of such notice is the "Termination Date"). If the Executive's
     employment is terminated by the Company without Cause, including without
     limitation by reason of the Executive's failure to achieve stated goals or
     milestones, on the Termination Date (i) the Company shall pay the Executive
     a lump sum amount equal to two years Base Salary plus any accompanying
     benefits to which the Executive would be entitled during such two year
     period under Sections 4.3 and 4.4 of this Agreement (to the extent
     permitted by the then-current terms of the applicable benefit plans and
     subject to any employee contribution requirements applicable to the
     Executive on the date of termination) and (ii) all stock options granted to
     the Executive prior to the Termination Date shall immediately vest in the
     Executive. The payment to the Executive of any other benefits following the
     termination of the Executive's employment pursuant to this Section 5.1
     shall be determined by the Board in its sole discretion in accordance with
     the policies and practices of the Company.

5.2  For Cause by the Company. Notwithstanding any other provision of this
     Agreement, the Executive's employment hereunder may be terminated by the
     Company at any time for Cause. For purposes of this Agreement, "Cause"
     shall mean (i) the Executive's dishonesty in the performance of his duties
     hereunder, (ii) an act or acts on the Executive's part constituting a
     felony under the laws of the United States or any state thereof, or (iii)
     the Executive's material breach of his obligations under Section 6 and 7
     hereof, which breach shall remain uncured by the Executive for thirty (30)
     days following receipt

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     of notice from the Company specifying such breach. If the Executive's
     employment is terminated by the Company for Cause, the Company shall pay
     the Executive a lump sum amount equal to the accrued and unpaid portion of
     the Base Salary through the last day of his actual employment by the
     Company. The payment to the Executive of any other benefits following the
     termination of the Executive's employment pursuant to this Section 5.2
     shall be determined by the Board in its sole discretion in accordance with
     the policies and practices of the Company.

5.3  Disability. The Executive's employment hereunder may be terminated by the
     Company at any time in the event of the Disability of the Executive. For
     purposes of this Agreement, "Disability" shall mean the inability of the
     Executive to substantially perform his duties hereunder due to physical or
     mental disablement which continues for a period of six (6) consecutive
     months during the Employment Term, as determined by an independent
     qualified physician mutually acceptable to the Company and the Executive
     (or his personal representative) or, if the Company and the Executive (or
     such representative) are unable to agree on an independent qualified
     physician, as determined by a panel of three physicians, one designated by
     the Company, one designated by the Executive (or his personal
     representative) and one designated by the two physicians so designated. If
     the Executive's employment is terminated by the Company for Disability, the
     Company shall pay the Executive an amount equal to the Base Salary plus any
     benefits to which the Executive is entitled under Section 4.4 of this
     Agreement (to the extent permitted by the then-current terms of the
     applicable benefit plans and subject to any employee contribution
     requirements applicable to the Executive on the date of termination)
     through the date on which the Executive is first eligible to receive
     payment of disability benefits in lieu of Base Salary under the Company's
     employee benefit plans as then in effect. The payment to the Executive of
     any other benefits following the termination of the Executive's employment
     pursuant to this Section 5.3 shall be determined by the Board in its sole
     discretion in accordance with the policies and practices of the Company.

5.4  Death. The Executive's employment hereunder shall automatically terminate
     in the event of the Executive's death. If the Executive's employment is
     terminated by the death of the Executive, the Company shall pay to the
     Executive's estate or legal representative an amount equal to the Base
     Salary at the rate in effect at the time of the Executive's death through
     the day on which his death occurs. The payment to the Executive of any
     other benefits following the termination of the Executive's employment
     pursuant to this Section 5.4 shall be determined by the Compensation
     Committee of the Board in its sole discretion in accordance with the
     policies and practices of the Company.

5.5  Termination by the Executive. The Executive's employment hereunder may be
     terminated by the Executive at any time upon not less than ninety (90) days
     prior written notice from the Executive to the Company. If the Executive
     terminates his employment with the Company pursuant to this Section 5.5,
     the Company shall pay the Executive an amount equal to the Base Salary
     through the last day of his actual employment by the Company; provided,
     however, if such voluntary termination is by reason of a demotion of the
     Executive from his position as President and Chief Executive Officer or a
     decrease in the Base Salary of the Executive, the Company shall pay the
     Executive a lump sum amount equal to the prior Base Salary plus any
     benefits to which the Executive is entitled under Section 4.4 of this
     Agreement (to the extent permitted by the then-current terms of the
     applicable to the Executive on the date of termination) through the
     conclusion of a period of two years from the date of such termination.

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5.6  Notice of Termination. Any purported termination of employment by the
     Company or by the Executive shall be communicated by written Notice of
     Termination to the other party hereto in accordance with Section 9 hereof.
     For purposes of this Agreement, a "Notice of Termination" shall mean a
     notice which shall indicate the specific termination provision in this
     Agreement relied upon and shall set forth in reasonable detail the facts
     and circumstances claimed to provide a basis for termination of employment
     under the provision so indicated.

5.7  Survival.  The provisions of Sections 6 and 7 shall survive the termination
     of this Agreement.

     6.  Non-Competition.  The Executive acknowledges and recognizes the highly
         ---------------
competitive nature of the businesses of the Company and accordingly agrees that
during the Employment Term and for a period of one (1) year after expiration or
termination of the Executive's employment hereunder:

6.1  The Executive will not engage in any activity including without limitation
     becoming an employee, investor (except for passive investments of not more
     than one percent (1%) of the outstanding shares of, or any other equity
     interest in, a company or entity listed or traded on a national securities
     exchange or in an over-the-counter securities market), officer, agent,
     partner or director of, or other participant in, any firm, person or other
     entity in any geographic area which is engaged in any activities in the
     field of the development, manufacturing, marketing, sale, distribution or
     commercialization of field emission displays ("FEDs"). Notwithstanding any
     provision of this Agreement to the contrary, upon the occurrence of any
     breach of this Section 6.1, if the Executive is employed by the Company,
     the Company may immediately terminate the employment of the Executive for
     Cause in accordance with the notice provisions contained in Sections 5.6
     and 9, and, whether or not the Executive is employed by the Company, the
     Company shall immediately cease to have any obligations to make payments to
     the Executive under this Agreement.

6.2  The Executive will not directly or indirectly assist others in engaging in
     any of the activities in which the Executive is prohibited to engage by
     clause 6.1 above.

6.3  The Executive will not directly or indirectly (a) induce any employee of
     the Company to engage in any activity in which the Executive is prohibited
     from engaging by clause 6.1 above or to terminate his or her employment
     with the Company, or (b) employ or offer employment to any person who was
     employed by the Company unless such person shall have ceased to be employed
     by the Company for a period of at least one (1) year.

6.4  It is expressly understood and agreed that (a) although the Executive and
     the Company consider the restrictions contained in this Section 6 to be
     reasonable, if a final judicial determination is made by a court of
     competent jurisdiction that the time or territory or any other restriction
     contained in this Agreement is unenforceable, this Agreement shall not be
     rendered void but shall be deemed to be enforceable to such maximum extent
     as such court may judicially determine or indicate to be enforceable and
     (b) if any restriction contained in this Agreement is determined to be
     unenforceable and such restriction cannot be amended so as to make it
     enforceable, such finding shall not affect the enforceability of any of the
     other restrictions contained herein.

     7.  Confidentiality.  The Executive will not at any time (whether during or
         ---------------
after his employment with the Company) disclose or use for his own benefit or
purposes or the benefit or purposes of any other

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person, firm, partnership, joint venture, association, corporation or other
organization, entity or enterprise other than the Company, any Confidential
Information. As used herein, the term "Confidential Information" shall mean,
without limitation, all Proprietary Materials (as defined below), any and all
information about inventions, improvements, modifications, discoveries, costs,
profits, markets, sales, products, key personnel, pricing policies, operational
methods, concepts, technical processes and applications, and other business
affairs and methods of the Company and of its affiliates, licensees,
collaborators, consultants, suppliers, and customers, as well as any other
information not readily available to the public, including without limitation
any information supplied by third parties to the Company under an obligation of
confidence. As used in this Agreement "Proprietary Materials" shall include,
without limitation, the following materials: any and all materials used in
construction of FEDs and completed FED samples as well as any and all
derivatives or replications derived from or relating to such materials.
Confidential Information may be contained in various media, including without
limitation patent applications, computer programs in object and/or source code,
flow charts and other program documentation, manuals, plans, drawings, designs,
technical specifications, laboratory notebooks, supplier and customer lists,
internal financial data, and other documents and records of the Company, whether
or not in written form and whether or not labeled or identified as confidential
or proprietary. The Executive further agrees that (a) upon termination or
expiration of his employment hereunder, the Executive will return immediately to
the Company any Proprietary Materials and any materials containing Confidential
Information then in the Executive's possession or under the Executive's control
and (b) he will not retain or use for his account at any time any trade name,
trademark or other proprietary business designation used or owned in connection
with the business of the Company.

     8.  Specific Performance.  The Executive acknowledges and agrees that the
         --------------------
Company's remedies at law for a breach or threatened breach of any of the
provisions of Section 6 or Section 7 would be inadequate and, in recognition of
this fact, the Executive agrees that, in the event of such a breach or
threatened breach, in addition to any remedies at law, the Company, without
posting any bond, shall be entitled to obtain equitable relief in the form of
specific performance, temporary restraining orders, temporary or permanent
injunctions or any other equitable remedy which may then be available.

     9.  Notices. Any notice hereunder by either party to the other shall be
         -------
given in writing by personal delivery, overnight mail via a reputable overnight
courier, facsimile or registered mail, return receipt requested, addressed, if
to the Company, to the attention of the Chairman of the Board at the Company's
executive offices or to such other address as the Company may designate in
writing at any time or from time to time to the Executive, and if to the
Executive, to his most recent address on file with the Company. Notice shall be
deemed given, if by personal delivery, on the date of such delivery or, if by
overnight mail, on the next business day after delivery of the notice to the
overnight courier, if by facsimile, on the business day following receipt of
answer back or facsimile information or, if by registered mail, on the date
shown on the applicable return receipt.

     10.  Assignment. This Agreement may not be assigned by either party without
          ----------
the prior written consent of the other party. The Company shall require any
persons, firm or corporation succeeding to all or substantially all of the
business or assets of the Company whether by purchase, merger or consolidation
to expressly assume and agree to perform this Agreement.

     11.  Entire Agreement. Except for the 1998 agreement evidencing the grant
          ----------------
to the Executive of options to purchase 300,000 shares of the Company's common
stock, this Agreement contains the entire


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agreement between the Company and the Executive with respect to the subject
matter hereof and there have been no oral or other agreements of any kind
whatsoever as a condition precedent or inducement to the signing of this
Agreement or otherwise concerning this Agreement or the subject matter hereof.

     12.  Expenses.  Each party shall pay its own expenses incident to the
          --------
performance or enforcement of this Agreement, including all fees and expenses of
its counsel for all activities of such counsel undertaken pursuant to this
Agreement, except as otherwise herein specifically provided.  If any action at
law or equity is necessary to enforce or interpret the terms of this Agreement,
the prevailing party shall be entitled to reimbursement of reasonable attorney's
fees and other costs incurred by such party in connection with such action, in
addition to any other relief to which such party is entitled.

     13.  Arbitration. In the event any dispute shall arise between the Company
          -----------
and the Executive with respect to any of the terms and conditions of this
Agreement, then such dispute shall be submitted and finally settled by
arbitration under the rules of the American Arbitration Association. The award
rendered by the arbitrator shall be final and binding upon the parties hereto,
and judgment upon the award rendered may be entered by either party in any court
that would ordinarily have jurisdiction over the parties or the subject matter
of the controversy or claim. Each party shall pay its own expenses incident to
such arbitration, including attorneys' fees. The parties agree not to institute
any litigation or proceedings against each other in connection with this
Agreement except as provided in this Section 13.

     14.  Waivers and Further Agreements. Any waiver of any terms or conditions
          ------------------------------
of this Agreement shall not operate as a waiver of any other breach of such
terms or conditions or any other term or condition, nor shall any failure to
enforce any provision hereof operate as a waiver of such provision or of any
other provision hereof; provided, however, that no such written wavier, unless
it, by its own terms, explicitly provides to the contrary, shall be construed to
effect a continuing waiver of the provision being waived and no such waiver in
any instance shall constitute a waiver in any other instance or for any other
purpose or impair the right of the party against whom such waiver is claimed in
all other instances or for all other purposes to require full compliance with
such provision. Each of the parties hereto agrees to execute all such further
instruments and documents and to take all such further action as the other party
may reasonably require in order to effectuate the terms and purposes of this
Agreement.

     15.  Amendments.  This Agreement may not be amended, nor shall any waiver,
          ----------
change, modification, consent or discharge be effected except by an instrument
in writing executed by or on behalf of the party against whom enforcement of any
waiver, change, modification, consent or discharge is sought.

     16.  Severability. If any provision of this Agreement shall be held or
          ------------
deemed to be, or shall in fact be, invalid, inoperative or unenforceable as
applied to any particular case in any jurisdiction or jurisdictions, or in all
jurisdictions or in all cases, because of the conflict of any provision with any
constitution or statute or rule of public policy or for any other reason, such
circumstance shall not have the effect of rendering the provision or provisions
in question invalid, inoperative or unenforceable in any other jurisdiction or
in any other case or circumstance or of rendering any other provision or
provisions herein contained invalid, inoperative or unenforceable to the extent
that such other provisions are not themselves actually in conflict with such
constitution, statute or rule of public policy, but this Agreement shall be
reformed and construed in any such jurisdiction or case as if such invalid,
inoperative or

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unenforceable provision had never been contained herein and such provision
reformed so that it would be valid, operative and enforceable to the maximum
extent permitted in such jurisdiction or in such case.

     17.  Counterparts. This Agreement may be executed in two or more
          ------------
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument, and in pleading or
proving any provision of this Agreement, it shall not be necessary to produce
more than one of such counterparts.

     18.  Section Headings.  The headings contained in this Agreement are for
          ----------------
reference purposes only and shall not in any way affect the meaning or
interpretation of this Agreement.

     19.  Governing Law.  This Agreement shall be governed by and construed and
          -------------
enforced in accordance with the law (other than the law governing conflict of
law questions) of the state of Delaware.

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     IN WITNESS WHEREOF, the parties have executed or caused to be executed this
Agreement as of the date first written above.

                              PIXTECH, INC.

                              By: /s/ J.L. Grand Clement
                                  -------------------------------
                                  Name:  Jean-Luc Grand-Clement
                                  Title:  Chairman of the Board

                              DIETER MEZGER

                                  /s/ Dieter Mezger
                              -----------------------------------

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                                  SCHEDULE A
                                  ----------

                            Business Relationships
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