[Thermo Electron Letterhead]


                                          June 15, 1999


Kristine Stotz Langdon
225 Common Street
Dedham, Massachusetts 02026

Dear Kristine:

      This letter  confirms  our  agreement  regarding  your  resignation  as an
officer and director of Thermo Vision Corporation (the "Company") and any of its
subsidiaries  or  affiliates  and your  continuing  employment  as a non-officer
employee of the Company, or another business unit of Thermo Electron Corporation
("Thermo  Electron") as reasonably  designated by Thermo  Electron in Waltham or
Franklin, Massachusetts.

      1.  Resignation:  You hereby  resign  effective  as of June 15,  1999 (the
"Resignation  Date") all of your  positions  as an officer  and  director of the
Company and all of its subsidiaries and affiliates.

      2.    Continuation of Employment:

                   (a)  Although you are  resigning as an officer and  director,
      your employment with the Company in a non-executive position will continue
      until  Friday,  November  26, 1999 (the  "Employment  Termination  Date").
      During  the  period  from the  Resignation  Date  through  the  Employment
      Termination Date (the "Interim Period"),  the Company shall pay to you, at
      such times and at such  intervals  as the Company  pays its  employees  in
      general,  your current  base salary at a rate of $139,000  per annum.  You
      will not be entitled to earn a bonus for the Interim Period or any portion
      thereof.

            (b) During the Interim Period,  you shall be entitled to participate
      in the benefit  programs that the Company  establishes and makes available
      from time to time to its  non-executive  employees to the extent that your
      position,  tenure,  salary, age, health and other  qualifications make you
      eligible to participate.

            (c) During the Interim Period,  you may continue to use your current
      leased vehicle and the Company shall continue to pay all associated  lease
      payments and automobile  insurance during this period. You agree to return
      the leased vehicle to the Company on the Employment Termination Date.




<PAGE>


Kristine Stotz Langdon
June 15, 1999
Page 2

            (d) The Company retains the right to terminate your employment prior
      to the Employment  Termination Date for Cause,  immediately upon notice to
      you.  "Cause"  shall  mean  your (a)  conviction  of or entry of a plea of
      guilty or nolo contendere to a felony or a misdemeanor  involving material
      fraud or  dishonesty,  (b) material  fraud or  dishonesty in the course of
      your continuing  employment by the Company,  (c) gross  misconduct that is
      materially  injurious  to  the  Company  or any  of  its  subsidiaries  or
      affiliates,   or  (d)  gross   neglect   of  your   material   duties  and
      responsibilities  as an employee of Thermo Electron or the Company. In the
      event you are  terminated  for  Cause,  the  Company  shall pay to you the
      compensation  and benefits that would have  otherwise  been payable to you
      through  the last day of your  actual  employment  as well as the  amounts
      specified in paragraphs 3, 4, 5, and 6 of this Agreement.

      3.  Severance  Pay: On November 26, 1999,  the Company will pay you a lump
sum severance payment of $139,000, representing one year's base salary.

      4. Accrued  Vacation:  You will be paid for any of your accrued but unused
vacation as of the Employment  Termination Date. You will cease to earn vacation
or other paid time off as of the Resignation Date.

      5.  Outplacement  Services:  The Company will  reimburse  you for expenses
actually  incurred  by you in  connection  with  outplacement  services up to an
aggregate amount of $15,000.

      6. 1999 Bonus:  On November 26, 1999, you will be paid a bonus of $22,500,
representing one-half of the 1999 calendar year reference bonus.

      7. Full  Payment:  You agree that all payments to be provided to you under
paragraphs 2, 3, 4, 5, and 6 of this Agreement are in complete  satisfaction  of
any and all  compensation  due to you from the Company  through  the  Employment
Termination Date.

      8.  Reference:  Attached  hereto is a letter of reference  from Dr. George
Hatsopoulos.  This  letter  will be  provided  upon your  request in response to
inquiries by  prospective  employers  concerning  you,  your  employment or your
departure from the Company. Such letter shall be provided in lieu of any oral or
written comments by any officer or director of the Company or Thermo Electron in
response to such  inquiries.  Instructions  to this effect will be  displayed in
your personnel  record.  You will direct that all requests for  information  and
responses to be sent to Thermo Electron's Director of Human Resources.

      9. Voice Mail: For the period from the Employment Termination Date through
March 31, 2000, your secretary or another  secretary's  voice on your voice mail
will state  "Kristine  Langdon left the company on November 26, 1999. She may be
reached at 781-329-6166 (or such other number designated by you)."

<PAGE>
Kristine Stotz Langdon
June 15, 1999
Page 3


      10.  Employee  Benefit  Programs:  Your  participation  in all  applicable
employee  benefit  programs  of the  Company  shall  cease as of the  Employment
Termination  Date in  accordance  with the  terms of those  programs.  Beginning
November  27, 1999  through May 26,  2001,  medical  and dental  coverages  will
continue  under  COBRA.  The Company  will pay the entire  monthly  premium cost
associated  with such  coverage  through May 26, 2001;  provided,  however,  the
Company's  obligation  to provide  such  coverage  under  COBRA,  including  its
obligation to pay the monthly premium costs associated therewith, shall cease in
the event of your  acceptance  of a  position  with an  employer  who offers you
health care insurance.  You will also have the option, at your sole expense,  of
converting  your  basic  (not   supplemental)  life  insurance  coverage  to  an
individual  plan through  Prudential.  If interested,  please let us know within
fifteen (15) days of the Employment  Termination Date and conversion information
will be furnished to you. A conversion option is not available for short or long
term disability coverage.

      11. Money Match Plus Plan:  Your active  participation  in the Money Match
Plus Plan shall end on the  Employment  Termination  Date.  Information  will be
provided to you regarding  various election  options  available to you regarding
your account. Subject to compliance with all applicable legal requirements,  the
Company  agrees to cooperate  with you and your advisors in the transfer of your
Money Match Plus Plan account  balance to another plan or account  designated by
you.

      12.  Stock  Options:  During the Interim  Period,  you will be entitled to
retain your current stock options in the Company and any of its  subsidiaries or
affiliates,  all of which  shall  continue to operate in  accordance  with their
respective  terms.  As of the Employment  Termination  Date,  such options shall
cease  vesting  and  no  further  lapsing  of  repurchase  rights  shall  occur.
Subsequently, if you do not exercise your vested options within ninety (90) days
of your Employment  Termination  Date, your options will expire and be canceled,
and you will have no further rights with respect to your options.

      13.  Taxes:  All  payments by the  Company  under this  Agreement  will be
reduced by all taxes and other  amounts that the Company is required to withhold
under applicable law and all other deductions authorized by you.

      14. Company  Property:  On or before the Employment  Termination Date, you
will return to the  Company any and all  documents,  materials  and  information
related to the Company, or its subsidiaries,  affiliates or businesses,  and all
other property of the Company, including, without limitation,  credit cards, the
leased company car, files, telephones, and personal computers in your possession
or control.  Further,  you agree that after the Employment  Termination Date you
will not for any  purpose  attempt  to access or use any  computer  or  computer
network or system,  including without  limitation any electronic mail system, of
the Company or any of its subsidiaries or affiliates.
<PAGE>
Kristine Stotz Langdon
June 15, 1999
Page 4


      15. Release:  In exchange for the consideration  described in paragraphs 3
and 6 hereof, you hereby release and discharge the Company,  Thermo Electron and
their  respective  subsidiaries  and  affiliates,  and each of their  respective
current, former or future officers, directors, employees, shareholders, employee
benefit  plans  and  plan  administrators,  agents,  representatives  and  legal
predecessors and successors (the "Releasees")  from all claims,  liabilities and
causes of action,  whether known or unknown,  which you have, may have, or claim
to have against any of them as of the date hereof, including, without limitation
those  based upon or arising out of your  employment  with the  Company,  Thermo
Electron or any of their respective subsidiaries or affiliates,  the termination
of your employment and other relationships with the Company, Thermo Electron and
any of their subsidiaries or affiliates,  your service as an officer or director
of the Company,  Thermo Electron or any of their subsidiaries or affiliates,  or
any of the Company's or Thermo Electron's policies,  procedures or requirements;
provided,  however,  nothing in this Agreement is intended to, or shall have the
effect of terminating your rights to  indemnification,  if any, from the Company
pursuant to  applicable  law  (including  but not limited to Delaware  corporate
law),  the  Certificate of  Incorporation  of the Company,  the  Indemnification
Agreement   between  you  and  the  Company   dated   November   14,  1997  (the
"Indemnification  Agreement"),  or  any  insurance  coverage  available  to  you
pursuant  to  policies   covering  Thermo  Electron  and  its  subsidiaries  and
affiliates,  including  the  Company.  You  agree  not to  assert  or  file,  or
participate  in,  encourage  or  instigate,  any claim or  lawsuit  against  the
Company,  Thermo  Electron or any of their  subsidiaries or affiliates or any of
the other Releasees,  including, but not limited to any claims arising from tort
or breach of contract, wrongful termination, fraudulent inducement of employment
or age, sex, race, disability or other discrimination under the Civil Rights Act
of 1964,  as amended by the Civil Rights Act of 1991,  the Fair  Employment  and
Housing Act, the Age Discrimination in Employment Act of 1967, as amended by the
Older Workers  Benefit  Protection Act of 1991, the Americans with  Disabilities
Act, ERISA, or any other federal, state or local laws prohibiting discrimination
or under any other federal,  state or local employment laws, each as amended and
in effect from time to time. You warrant that you have not filed or participated
in any lawsuits, complaints, claims, proceedings or charges against the Company,
Thermo  Electron or any of their  subsidiaries or affiliates or any of the other
Releasees with any local, state or federal court or agency.

      YOU  UNDERSTAND  AND  ACKNOWLEDGE  THAT YOU HAVE BEEN  ADVISED TO SEEK THE
ADVICE OF AN ATTORNEY  PRIOR TO SIGNING  THIS  AGREEMENT  AND RELEASE AND TO THE
EXTENT  DESCRIBED  HEREIN  YOU ARE GIVING UP ANY LEGAL  CLAIMS YOU HAVE  AGAINST
COMPANY, THERMO ELECTRON AND THEIR SUBSIDIARIES AND AFFILIATES AND EACH OF THEIR
RESPECTIVE CURRENT,  FORMER OR FUTURE OFFICERS,  DIRECTORS,  EMPLOYEES,  AGENTS,
REPRESENTATIVES, LEGAL PREDECESSORS AND SUCCESSORS BY SIGNING THIS AGREEMENT AND
RELEASE.  YOU  FURTHER  UNDERSTAND  THAT YOU MAY HAVE 21 DAYS TO  CONSIDER  THIS
AGREEMENT AND RELEASE,  THAT YOU MAY REVOKE IT AT ANY TIME DURING THE SEVEN DAYS
AFTER  YOU  SIGN IT,  AND THAT IT WILL NOT  BECOME  EFFECTIVE  UNTIL  THE  7-DAY
REVOCATION PERIOD HAS PASSED WITHOUT REVOCATION.  YOU ACKNOWLEDGE THAT YOU FULLY
UNDERSTAND  YOUR RIGHT TO TAKE 21 DAYS TO CONSIDER  SIGNING THIS  AGREEMENT  AND

<PAGE>

Kristine Stotz Langdon
June 15, 1999
Page 5


RELEASE AND, AFTER HAVING  SUFFICIENT TIME TO CONSIDER YOUR OPTIONS,  YOU HEREBY
WAIVE YOUR RIGHT TO TAKE THE FULL 21-DAY PERIOD.  YOU  ACKNOWLEDGE  THAT YOU ARE
SIGNING THIS  AGREEMENT  AND RELEASE  KNOWINGLY,  WILLINGLY AND  VOLUNTARILY  IN
EXCHANGE  FOR  THE  CONSIDERATION  DESCRIBED  IN  PARAGRAPHS  3  AND  6 OF  THIS
AGREEMENT.

      16.  Restriction  on Purchase or Sale of Common Stock:  You understand and
acknowledge  that you will continue to be a "Reporting  Person," for purposes of
Section 16 of the Securities Exchange Act of 1934, as amended, and the rules and
regulations  promulgated  thereunder,  and you will  remain  subject  to insider
trading regulations under the federal securities laws for a period of six months
following the  Resignation  Date and that during that period you are required to
preclear  transactions  in the Company and its  affiliates'  securities with the
Company's Stock Transaction  Coordinator,  Ms. Pauline I. Northern. You are also
urged to contact the Corporate Secretary of the Company,  Ms. Sandra L. Lambert,
should you have any  questions  regarding  compliance  with the insider  trading
regulations under the federal securities laws.

      17. No Hiring. For the period beginning on the Resignation Date and ending
on  November  26,  2000,  you hereby  agree you shall not,  either  directly  or
indirectly as a stockholder,  investor,  partner, director, officer, employee or
otherwise,  solicit or attempt to induce any  employee  of the Company or Thermo
Optek  Corporation  ("Optek"),  or  any  of  their  respective  subsidiaries  or
affiliates (other than clerical or administrative personnel) to terminate his or
her employment  with such entity,  or attempt to induce any customer or supplier
of the Company, Thermo Electron or Optek or any of their respective subsidiaries
or affiliates to terminate its relationship with such entity.

      18.  Non-Disparagement:  You agree that you will  continue  to support and
promote the  interests of the  Company,  Thermo  Electron  and their  respective
subsidiaries and affiliates and that you will not disparage the Company,  Thermo
Electron or their respective subsidiaries or affiliates, or any of the people or
organizations  connected  with them,  or do or say  anything  that  harms  their
interests or  reputation.  The Company agrees that it will cause the officers of
Thermo Electron,  Optek, and the Company not to disparage you or otherwise do or
say anything  that harms your  reputation  and that the Company  shall be solely
responsible  for any breach of the provisions  contained in this paragraph 18 by
any such  officers.  Nothing in this paragraph 18 shall prevent the parties from
(i) complying with compulsory  legal process or otherwise  making  disclosure in
connection  with  litigation  or  administrative  proceedings,  (ii) making such
disclosures as are necessary to obtain legal advice, (iii) making disclosures as
are required by federal, state or local regulatory authorities,  and (iv) making
disclosures which by law are required or cannot be prohibited.

<PAGE>
Kristine Stotz Langdon
June 15, 1999
Page 6


      19.  Cooperation:  You agree to reasonably  cooperate with Thermo Electron
and the Company  with respect to all matters  arising  during or related to your
employment,  including but not limited to  cooperation  in  connection  with any
governmental  investigation,  litigation or regulatory or other proceeding which
may have arisen or which may arise following the signing of this Agreement.

      20. Waiver of Jury Trial: Each of the parties hereby expressly, knowingly,
and  voluntarily  waives all benefit and  advantage  and any right to a trial by
jury,  and each agrees that she or it will not at any time insist upon, or plead
or in any  manner  whatsoever  claim a trial by jury in any  action  arising  in
connection with this Agreement.

      21. Entire Agreement: This Agreement contains the entire agreement between
you,  the  Company,  Thermo  Electron  and  their  respective  subsidiaries  and
affiliates and replaces all prior and contemporaneous agreements, communications
and  understandings,  whether written or oral, with respect to your  employment,
resignation,  and termination of your employment and all related  matters.  This
Agreement will be governed by and interpreted in accordance with the laws of the
Commonwealth of Massachusetts without regard to choice of law provisions.

      22. Severability:  If one or more provisions of this Agreement are held to
be invalid  or  unenforceable  under  applicable  law by any court of  competent
jurisdiction, such provision or provisions shall be excluded from this Agreement
and replaced  with a provision  which is  enforceable  and comes  closest to the
intent of the parties underlying the unenforceable  provision or provisions.  In
such event,  all  remaining  provisions of this  Agreement  shall remain in full
force and effect.  Any provisions held invalid or unenforceable  only in part or
degree  will  remain in full force and effect to the extent not held  invalid or
unenforceable.

      23. Relief:  In the event of breach of the provisions of this Agreement by
any party, in addition to any other rights that the other parties may have under
law or in equity,  each party shall have the right to specific  performance  and
injunctive  relief, it being acknowledged and agreed that money damages will not
provide an adequate remedy.

      24.  Successors and Assigns:  No party hereto may assign any of its rights
under this Agreement  without the prior written consent of the other party. This
Agreement  is binding on each of the  parties'  permitted  assigns,  successors,
heirs, administrators and executors.

      25. Company Information and Invention Agreement.  You agree to execute and
comply with the terms of the Company Information and Invention Agreement, a copy
of which is attached  hereto.  Such  agreement  supercedes  any prior  agreement
covering  the same  subject  matter that you may have signed with the Company or
any of its affiliates or subsidiaries.

      26. Voluntary Agreement:  In signing this Agreement,  you give the Company
assurance that you have signed it voluntarily and with a full  understanding  of
its  terms  and that  you  have had  sufficient  opportunity  to  consider  this
Agreement and to consult with anyone of your choosing before signing it.


<PAGE>

Kristine Stotz Langdon
June 15, 1999
Page 7


      If the terms of this  Agreement  are  acceptable  to you,  please sign and
return it to the undersigned. At the time you sign and return this Agreement, it
will take effect as a  legally-binding  agreement between you and the Company on
the basis set forth above.

                                        THERMO VISION CORPORATION


                                        By:    /s/ Earl R. Lewis
                                             --------------------------------
                                        Name:  Earl R. Lewis
                                        Title: Chairman of the Board


                                        THERMO ELECTRON CORPORATION


                                        By:    /s/ Anne Pol
                                             --------------------------------
                                        Name:  Anne Pol
                                        Title: Senior Vice President

Accepted and Agreed to:


/s/ Kristine Stotz Langdon
--------------------------
    Kristine Stotz Langdon