SECURITIES AND EXCHANGE COMMISSION
                              WASHINGTON, DC 20549
                   -------------------------------------------
                                    FORM 10-K

   (mark one)
   [ X ] Annual Report Pursuant to Section 13 or 15(d) of the Securities
         Exchange Act of 1934 for the fiscal year ended December 28, 1996

   [   ] Transition Report Pursuant to Section 13 or 15(d) of the Securities
         Exchange Act of 1934

                         Commission file number 1-11757
                            THERMO OPTEK CORPORATION
             (Exact name of Registrant as specified in its charter)

   Delaware                                                        04-3283973
   (State or other jurisdiction of                           (I.R.S. Employer
   incorporation or organization)                         Identification No.)

   8E Forge Parkway
   Franklin, Massachusetts                                              02038
   (Address of principal executive offices)                        (Zip Code)
       Registrant's telephone number, including area code: (617) 622-1000

           Securities registered pursuant to Section 12(b) of the Act:

          Title of each class        Name of each exchange on which registered
     ----------------------------    -----------------------------------------
     Common Stock, $.01 par value             American Stock Exchange

           Securities registered pursuant to Section 12(g) of the Act:
                                      None

   Indicate by check mark whether the Registrant (1) has filed all reports
   required to be filed by Section 13 or 15(d) of the Securities Exchange Act
   of 1934 during the preceding 12 months (or for such shorter period that the
   Registrant was required to file such reports), and (2) has been subject to
   the filing requirements for at least the past 90 days. Yes [ X ]  No [   ]

   Indicate by check mark if disclosure of delinquent filers pursuant to Item
   405 of Regulation S-K is not contained herein, and will not be contained,
   to the best of the Registrant's knowledge, in definitive proxy or
   information statements incorporated by reference into Part III of this Form
   10-K or any amendment to this Form 10-K. [   ]

   The aggregate market value of the voting stock held by nonaffiliates of the
   Registrant as of January 24, 1997, was approximately $38,563,000.

   As of January 24, 1997, the Registrant had 48,450,000 shares of Common
   Stock outstanding.

                       DOCUMENTS INCORPORATED BY REFERENCE

   Portions of the Registrant's Annual Report to Shareholders for the year
   ended December 28, 1996, are incorporated by reference into Parts I and II.

   Portions of the Registrant's definitive Proxy Statement for the Annual
   Meeting of Shareholders to be held on June 2, 1997, are incorporated by
   reference into Part III.
PAGE
<PAGE>
                                     PART I


    Item 1.  Business

    (a)  General Development of Business

        Thermo Optek Corporation (the Company or the Registrant) is a
    worldwide leader in the development, manufacture, and marketing of
    analytical instruments and has technologies in electro-optic components
    and systems. The Company's instruments are used in the quantitative and
    qualitative chemical analysis of elements and molecular compounds in
    solids, liquids, and gases. These products are used by its customers for
    productivity enhancement, research and development, quality control, and
    testing applications in the environmental testing, chemical,
    metallurgical, food and beverage, pharmaceutical, and petroleum
    industries; and by forensic laboratories, research organizations, and
    educational institutions. The Company was incorporated in Delaware in
    August 1995 as a wholly owned subsidiary of Thermo Instrument Systems
    Inc. (Thermo Instrument). Thermo Instrument is a publicly traded,
    majority-owned subsidiary of Thermo Electron Corporation (Thermo
    Electron).

        An element of the Company's strategy is to combine its internal
    growth with the acquisition of complementary products and technologies.
    In December 1995, Thermo Instrument acquired the assets of the analytical
    instruments division of Analytical Technology, Inc. (the ATI Division), a
    manufacturer of analytical instruments, for $42.5 million. In April 1996,
    the Company acquired the ATI Division's Mattson and Unicam businesses
    from Thermo Instrument for an aggregate purchase price of $36.6 million.
    These businesses have been included in the Company's historical results
    of operations from December 1, 1995, the date on which they were acquired
    by Thermo Instrument. Mattson is a Wisconsin-based manufacturer of FT-IR
    spectroscopy instruments and Unicam is a Cambridge, UK-based manufacturer
    of atomic absorption and ultraviolet/visible spectroscopy instruments. 

        Effective March 29, 1996, the Company acquired two businesses, A.R.L.
    Applied Research Laboratories S.A. (ARL) and VG Elemental, and four
    associated sales organizations located in South Africa, Austria, Sweden,
    and Canada from Thermo Instrument for approximately $55.2 million in cash
    and the assumption of $16.6 million in debt. These businesses were
    originally part of the Scientific Instruments Division of Fisons plc
    (Fisons), a wholly owned subsidiary of Rhone-Poulenc Rorer, Inc., a
    substantial portion of which was acquired by Thermo Instrument on March
    29, 1996. The purchase price is subject to a post-closing adjustment
    based on a post-closing adjustment to be negotiated with Fisons by Thermo
    Instrument in connection with the negotiations for settlement of the
    final purchase price for all of the businesses of Fisons acquired by
    Thermo Instrument. ARL is a Switzerland-based manufacturer of arc/spark
    AE spectrometers and X-ray fluorescence instruments. VG Elemental is a
    U.K.-based manufacturer of inductively coupled plasma/mass spectrometers.

        In June and July 1996, the Company sold 3,450,000 shares of its
    common stock in an initial public offering at $13.50 per share for net
    proceeds of $42.9 million. In October 1995, the Company issued and sold

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    $96.3 million principal amount of 5% subordinated convertible debentures
    due 2000. The debentures are convertible into shares of the Company's
    common stock at a conversion price of $14.85 per share and are guaranteed
    on a subordinated basis by Thermo Electron. As of December 28, 1996,
    Thermo Instrument owned 45,000,000 shares of the common stock of the
    Company, representing 93% of such stock outstanding. Thermo Instrument
    develops, manufactures, and markets instruments used to detect and
    measure air pollution, radioactivity, complex chemical compounds, toxic
    metals, and other elements in a broad range of liquids and solids, as
    well as to control and monitor various industrial processes. As of
    December 28, 1996, Thermo Electron owned 144,900 shares of the common
    stock of the Company, representing 0.3% of such stock outstanding. These
    shares were purchased during 1996* in the open market for a total
    purchase price of $1,967,000. Thermo Electron is a world leader in
    environmental monitoring and analysis instruments, biomedical products
    such as heart-assist devices and mammography systems, paper-recycling and
    papermaking equipment, biomass electric power generation, and other
    specialized products and technologies. Thermo Electron also provides a
    range of services related to environmental quality.

    Forward-looking Statements

        Forward-looking statements, within the meaning of Section 21E of the
    Securities Exchange Act of 1934, are made throughout this Annual Report
    on Form 10-K. For this purpose, any statements contained herein that are
    not statements of historical fact may be deemed to be forward-looking
    statements. Without limiting the foregoing, the words "believes,"
    "anticipates," "plans," "expects," "seeks," "estimates," and similar
    expressions are intended to identify forward-looking statements. There
    are a number of important factors that could cause the results of the
    Company to differ materially from those indicated by such forward-looking
    statements, including those detailed under the caption "Forward-looking
    Statements" in the Registrant's 1996 Annual Report to Shareholders
    incorporated herein by reference.

    (b) Financial Information About Industry Segments

        The Company is engaged in one business segment: developing,
    manufacturing, and selling analytical instruments.

    (c) Description of Business

        (i)  Principal Products and Services

        Analytical instruments are generally classified by their principal
    operating technologies. The Company's atomic emission (AE) and atomic
    absorption (AA) spectrometers comprise its elemental analysis product
    line, and FT-IR and FT-Raman spectrometers comprise its molecular
    analysis product line. In addition, through its Thermo Vision Corporation
    (Thermo Vision) subsidiary, the Company addresses the photonics
    marketplace for optical components, imaging systems, analytical 


    *   References to 1996, 1995, and 1994 herein are for the fiscal years
        ended December 28, 1996, December 30, 1995, and December 31, 1994,
        respectively.
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    instruments, and lasers. Thermo Vision develops and manufactures
    cost-effective, application-specific instruments, as well as components,
    systems, and subassemblies for analytical instruments.

    Elemental Analysis - AE and AA Spectrometers

        The Company produces a range of AE and AA spectrometers that are used
    to detect and measure metals and other elements in solid and liquid
    samples from ultratrace (parts per billion) to major concentrations.
    These instruments are used in a wide variety of applications, including
    testing environmental samples, such as soil and water, and food and
    drugs; analyzing blood, urine, and animal tissue; and process quality
    control and product quality assurance. The Company sells its products to
    customers in a wide range of industries, including those in manufacturing
    industries such as producers of aircraft, automobiles and trucks,
    computers, chemicals, food, pharmaceuticals, and primary metals; service
    industries such as waste management companies and commercial testing
    laboratories; and government and university laboratories.

        In AE spectrometers, the samples are excited by an energy source,
    causing the sample atoms to emit radiation. The radiation is then
    dispersed by a grating into its component light wavelengths, which are
    detected by a photo multiplier tube or a solid state detector. Each
    element has a characteristic wavelength that acts as a "fingerprint" for
    that element, which the instrument compares against a library of spectra
    for identification. The resulting data may be stored and manipulated by
    computer. AE spectrometers use either an electrical discharge (arc/spark)
    or a high frequency inductively coupled plasma (ICP) as the energy
    source. 

        Arc/spark instruments are used primarily for solid samples in highly
    capital-intensive processes such as steel and other primary metal
    production, foundries that fabricate raw metals, and production of
    products such as pipe and machine parts. Customers in these industries
    use the arc/spark instrument in near line quality control as part of the
    production process. Due to the high cost of these processes, the
    minimization of downtime and the maintenance of quality control are
    critical. For these reasons, reliability is frequently the most important
    feature to an arc/spark user. ARL, acquired in 1996, is a worldwide
    supplier of spectrochemical instrumentation based on arc/spark optical
    emission spectrometry and wavelength dispersive x-ray fluorescence
    (WDXRF) spectrometry. WDXRF spectrometers offer elemental analysis of a
    wide variety of materials in a highly precise and generally
    nondestructive manner.

        ICP spectrometers are used for both solid and liquid samples and
    allow for simultaneous multi-element testing. The largest users of ICP
    instruments are public and private environmental laboratories, which must
    test for multiple elements but which have well defined testing
    objectives. These users test for compliance with applicable environmental
    regulations, which prescribe the specific pollutants and concentrations
    to be identified. The Company has recently developed the first ultratrace
    ICP spectrometer that incorporates a solid state detector, the IRIS(TM),
    and the first combined optical emission mass spectrometer, the POEMS(R),
    which allows customers to perform with one instrument analyses that

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    previously would have required multiple instruments. In addition, the
    IRIS incorporates Windows(TM)-based software that facilitates use of the
    instrument with relatively minimal training. ICP instruments can also be
    coupled with a mass spectrometer (ICP/MS) to provide detection at the
    parts per trillion level. This high level of sensitivity is often
    required by semiconductor, pharmaceutical, and chemical companies in both
    research and development and quality control functions. The Company has
    recently introduced the second generation of its POEMS ICP/MS, which
    incorporates several significant advances, including automated sample
    preparation and Windows-based software. POEMS is the first ICP/MS
    instrument to integrate a CID detector, which enhances the flexibility of
    the instrument. VG Elemental, acquired in November 1996, manufactures
    ICP/MS instruments that are utilized in the environmental, nuclear,
    semiconductor, biological, metals, and chemicals industries where
    critical, ultratrace detection of elements is required.

        Due to their sensitivity and relatively low cost, AA spectrometers
    are the instrument of choice for environmental applications. Certain of
    the EPA's protocols for the determination of toxic metals in water and
    wastes are written for AA spectrometers. In addition to environmental
    testing, AA spectrometers are used in biological testing and for testing
    in the agricultural and petroleum industries. AA spectrometers use a
    graphite furnace or flame to heat the sample and incorporate a hollow
    cathode lamp that contains the element to be measured. Because the hollow
    cathode lamp radiates at the same wavelength as the sample atoms, the
    sample atoms absorb radiation from the lamp, and the detector measures
    this absorption. The 1996 acquisition of Unicam has increased the
    Company's product base in AA spectrometers, as well as its presence in
    the European market, and will complement its other products and presence
    in the environmental, life science research, pharmaceutical, and chemical
    markets.

    Molecular Analysis - FT-IR and FT-Raman Spectrometers

        Thermo Optek is among the world's largest manufacturers of molecular
    analysis instruments that utilize FT-IR and FT-Raman spectroscopic
    techniques. Using these "vibrational" spectroscopic techniques, customers
    are able to nondestructively analyze liquids and solids for their
    molecular composition. These techniques permit the analysis of samples in
    their packaging, which eliminates much of the time involved with sample
    preparation.

        The Company's FT-IR and FT-Raman spectrometers are used principally
    in research and development and quality control in a variety of
    industries. Chemical and pharmaceutical companies use FT-IR and FT-Raman
    spectrometers for verification, identification, and quantification of
    chemical materials and mixtures because of the superior ability of these
    instruments to provide detailed structural information. Other
    applications involve analysis of total petroleum hydrocarbon content and
    other contamination in soil and water, and monitoring of industrial waste
    streams.

        The Company also offers several lines of infrared microscopes and
    micro-imaging accessories. The Company believes it is the world's leading
    supplier of these devices, which are utilized, individually or in

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    conjunction with FT-IR spectrometers, to obtain the infrared spectrum of
    small samples in the range from 20 to 1000 microns.

    Thermo Vision Corporation

        Through its Thermo Vision subsidiary, the Company addresses the
    photonics marketplace for optical components, imaging systems, analytical
    instruments, and lasers. Thermo Vision is pursuing applications of its
    photonics technologies in a wide array of markets such as dental imaging,
    semiconductor processing, high-energy physics, and nuclear inspection, in
    addition to analytical instrumentation. Within instrumentation, Thermo
    Vision addresses the market for cost-effective, application-specific
    instruments and for optical components, systems, and subassemblies for
    analytical instrumentation. The Company believes that there is a trend in
    the market for analytical instruments toward the development of
    lower-cost instruments that are easy to use and capable of performing
    discrete analyses accurately and reliably. Thermo Vision is building a
    sales and service channel for optical components and lower-cost
    instruments that cannot be effectively or profitably sold or serviced
    through the channels used for larger, higher-performance analytical
    instruments.

        In February 1996, Thermo Vision acquired Corion Corporation (Corion),
    a manufacturer of commercial optical filters, for $5.1 million in cash
    and Oriel Corporation (Oriel), a manufacturer and distributor of
    electro-optical instruments and components, for $11.8 million in cash and
    the assumption of $0.7 million in debt. In addition, Thermo Vision
    acquired Laser Science, Inc. (LSI), a manufacturer of nitrogen, tunable
    dye, and pulsed lasers, in February 1997 for $3.6 million in cash. The
    Company believes that these acquisitions will further Thermo Vision's
    strategic move into the photonics marketplace by broadening its product
    offerings and providing a base for low-cost distribution.

        In 1996 and 1995, the Company derived revenues of $30.5 million and
    $6.1 million, respectively, from its Thermo Vision businesses.

        In September 1996, the Company announced its intent to spin out
    Thermo Vision through a distribution of all of its outstanding capital
    stock in the form of a dividend to the Company's shareholders. The
    Company anticipates completing the spinout in 1997, and is seeking a
    Letter Ruling from the Internal Revenue Service stating that the proposed
    spinout will have no current tax effect on Thermo Optek or its
    shareholders. The Company would distribute the shares upon receipt of the
    Letter Ruling and satisfaction of other conditions, including the listing
    of the Thermo Vision shares on the American Stock Exchange. Upon
    completion of this proposed transaction, Thermo Vision would be a
    majority-owned subsidiary of Thermo Instrument.

    Sales and Marketing

        The Company markets its instruments internationally through its own
    worldwide sales force and through a network of dealers and distributors.
    In addition, the Company sells certain components and instruments
    pursuant to original equipment manufacturer (OEM) arrangements under
    which third parties purchase and resell the Company's products. The

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    Company's sales force is supported throughout the world by a customer
    support group which provides training, instrument servicing, and parts
    replacement.

        (ii) and (xi)  New Products; Research and Development

        The Company maintains active programs for the development of new
    technologies and the enhancement of existing products. In addition, the
    Company seeks to develop new applications for its products and
    technologies. Research and development expenses for the Company were
    $22.0 million, $13.0 million, and $10.5 million in 1996, 1995, and 1994,
    respectively.

        (iii)  Raw Materials

        Raw materials, components, and supplies purchased by the Company are
    either available from a number of different suppliers or from alternative
    sources that could be developed without a material adverse effect on the
    Company. To date, the Company has experienced no difficulties in
    obtaining these materials.

        (iv)  Patents, Licenses, and Trademarks

        The Company's policy is to protect its intellectual property rights,
    including applying for and obtaining patents when appropriate. The
    Company holds numerous patents relating to its technologies, with
    additional patents pending. The Company also enters into licensing
    agreements with other companies and government agencies in which it
    grants or receives rights to specific patents and technical know-how. The
    Company also considers technical know-how, trade secrets, and trademarks
    to be important to its business.

        (v)  Seasonal Influences

        There are no significant seasonal influences on the Company's sales
    of its products.

        (vi)  Working Capital Requirements

        There are no special inventory requirements or credit terms extended
    to customers that would have a material adverse effect on the Company's
    working capital.

        (vii)  Dependency on a Single Customer

        No single customer accounted for more than 10% of the Company's total
    revenues in any of the past three years.

        (viii)  Backlog

        The Company's backlog of firm orders was $67.2 million and $50.1
    million as of December 28, 1996, and December 30, 1995, respectively. The
    Company believes that substantially all of the backlog at December 28,
    1996, will be shipped or completed during 1997. The Company does not

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    believe that the size of its backlog is necessarily indicative of
    intermediate or long-term trends in its business.

        (ix)  Government Contracts

        Not applicable.

        (x)  Competition

        The Company competes in each of its markets primarily on performance,
    reliability, customer service, and price. In the market for AE and AA
    spectrometers and ICP/MS instruments, the Company competes primarily with
    The Perkin-Elmer Corporation and, to a lesser extent, Varian Associates,
    Inc. The Company competes in the arc/spark market primarily with Spectro.
    In the FT-IR and FT-Raman markets, the Company competes primarily with
    Perkin-Elmer; the Digilab division of Bio-Rad Laboratories, Inc.; Bruker
    Instruments, Inc.; and Bomem Inc. The Company entered the market for
    UV/Vis instruments with its acquisition of Unicam in 1996. The primary
    competitors in this market are Perkin-Elmer, Shimadzu, and
    Hewlett-Packard Co.

        (xii)  Environmental Protection Regulations

        The Company believes that compliance by the Company with federal,
    state, and local environmental protection regulations will not have a
    material adverse effect on its capital expenditures, earnings, or
    competitive position.

        (xiii)  Number of Employees

        As of December 28, 1996, the Company employed approximately 2,065
    people.

    (d) Financial Information About Exports by Domestic Operations and About
        Foreign Operations

        Financial information about exports by domestic operations and about
    foreign operations is summarized in Note 10 to Consolidated Financial
    Statements in the Registrant's 1996 Annual Report to Shareholders and is
    incorporated herein by reference.

    (e)  Executive Officers of the Registrant

                                       Present Title (Year First Became
    Name                        Age    Executive Officer)
    ------------------------    ---    ----------------------------------
    Earl R. Lewis               53     President, Chief Executive Officer, 
                                         and Director (1995)
    Dr. Robert J. Rosenthal     40     Executive Vice President and
                                         Chief Operating Officer (1995)
    John N. Hatsopoulos         62     Vice President and Chief Financial
                                         Officer (1995)
    Kristine A. Langdon         38     Vice President (1995)
    Paul F. Kelleher            54     Chief Accounting Officer (1995)

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        Each executive officer serves until his successor is chosen or
    appointed by the Board of Directors and qualified or until his earlier
    resignation, death, or removal. Mr. Lewis, Dr. Rosenthal, and Ms. Langdon
    have held their respective positions in the Company since its inception
    in August 1995. Mr. Lewis is also a Vice President of Thermo Electron and
    Executive Vice President and Chief Operating Officer of Thermo
    Instrument. Mr. Lewis served as President of Thermo Jarrell Ash until
    December 1995. Mr. Rosenthal has been President of Nicolet since 1993.
    Ms. Langdon has served as Chief Executive Officer and President of Thermo
    Vision since its inception in January 1995. Ms. Langdon served as
    Director of Business Development of Thermo Jarrell Ash from April 1994
    until January 1995. Messrs. Hatsopoulos and Kelleher are full-time
    employees of Thermo Electron, but devote such time to the affairs of the
    Company as the Company's needs reasonably require.


    Item 2.  Properties

        The Company owns approximately 600,000 square feet of office and
    manufacturing space in Wisconsin, Colorado, England, and Switzerland, and
    leases an additional 600,000 square feet of office and manufacturing
    space under leases expiring from 1997 through 2013, principally in
    Massachusetts, Connecticut, and England. The Company believes that its
    facilities are in good condition and are suitable and adequate to meet
    current needs.


    Item 3.  Legal Proceedings

        Not applicable.


    Item 4.  Submission of Matters to a Vote of Security Holders

        Not applicable.



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                                     PART II

    Item 5.  Market for Registrant's Common Equity and Related Stockholder
             Matters

        Information concerning the market and market price for the
    Registrant's common stock, $.01 par value, and dividend policy is
    included under the sections labeled "Common Stock Market Information" and
    "Dividend Policy" in the Registrant's 1996 Annual Report to Shareholders
    and is incorporated herein by reference.


    Item 6.  Selected Financial Data

        The information required under this item is included under the
    sections labeled "Selected Financial Information" and "Dividend Policy"
    in the Registrant's 1996 Annual Report to Shareholders and is
    incorporated herein by reference.


    Item 7.  Management's Discussion and Analysis of Financial Condition and
             Results of Operations

        The information required under this item is included under the
    heading "Management's Discussion and Analysis of Financial Condition and
    Results of Operations" in the Registrant's 1996 Annual Report to
    Shareholders and is incorporated herein by reference.


    Item 8.  Financial Statements and Supplementary Data

        The Registrant's Consolidated Financial Statements as of December 28,
    1996, and Supplementary Data are included in the Registrant's 1996 Annual
    Report to Shareholders and are incorporated herein by reference.


    Item 9.  Changes in and Disagreements with Accountants on Accounting and
             Financial Disclosure

        Not applicable.



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                                    PART III

    Item 10.  Directors and Executive Officers of the Registrant

        The information concerning directors required under this item is
    incorporated herein by reference from the material contained under the
    caption "Election of Directors" in the Registrant's definitive proxy
    statement to be filed with the Securities and Exchange Commission
    pursuant to Regulation 14A, not later than 120 days after the close of
    the fiscal year. The information concerning delinquent filers pursuant to
    Item 405 of Regulation S-K is incorporated herein by reference from the
    material contained under the heading "Section 16(a) Beneficial Ownership
    Reporting Compliance" under the caption "Stock Ownership" in the
    Registrant's definitive proxy statement to be filed with the Securities
    and Exchange Commission pursuant to Regulation 14A, not later than 120
    days after the close of the fiscal year.


    Item 11.  Executive Compensation

        The information required under this item is incorporated herein by
    reference from the material contained under the caption "Executive
    Compensation" in the Registrant's definitive proxy statement to be filed
    with the Securities and Exchange Commission pursuant to Regulation 14A,
    not later than 120 days after the close of the fiscal year.


    Item 12.  Security Ownership of Certain Beneficial Owners and Management

        The information required under this item is incorporated herein by
    reference from the material contained under the caption "Stock Ownership"
    in the Registrant's definitive proxy statement to be filed with the
    Securities and Exchange Commission pursuant to Regulation 14A, not later
    than 120 days after the close of the fiscal year.


    Item 13.  Certain Relationships and Related Transactions

        The information required under this item is incorporated herein by
    reference from the material contained under the caption "Relationship
    with Affiliates" in the Registrant's definitive proxy statement to be
    filed with the Securities and Exchange Commission pursuant to Regulation
    14A, not later than 120 days after the close of the fiscal year.

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                                     PART IV

    Item 14. Exhibits, Financial Statement Schedules, and Reports on Form   
             8-K

    (a,d)     Financial Statements and Schedules

              (1) The consolidated financial statements set forth in the list
                  below are filed as part of this Report.

              (2) The consolidated financial statement schedule set forth in
                  the list below is filed as part of this Report.

              (3) Exhibits filed herewith or incorporated herein by reference
                  are set forth in Item 14(c) below.

             List of Financial Statements and Schedules Referenced in this
             Item 14

             Information incorporated by reference from Exhibit 13 filed
             herewith:

                  Consolidated Statement of Income
                  Consolidated Balance Sheet
                  Consolidated Statement of Cash Flows
                  Consolidated Statement of Shareholders' Investment
                  Notes to Consolidated Financial Statements
                  Report of Independent Public Accountants

             Financial Statement Schedules filed herewith:

                  Schedule II: Valuation and Qualifying Accounts

             All other schedules are omitted because they are not applicable
             or not required, or because the required information is shown
             either in the financial statements or in the notes thereto.


      (b)     Reports on Form 8-K

             None.


      (c)     Exhibits

              See Exhibit Index on the page immediately preceding exhibits.

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                                   SIGNATURES

         Pursuant to the requirements of Section 13 of the Securities
    Exchange Act of 1934, the Registrant has duly caused this report to be
    signed on its behalf by the undersigned, thereunto duly authorized.

    Date: March 17, 1997            THERMO OPTEK CORPORATION


                                    By: Earl R. Lewis
                                        -------------------------
                                        Earl R. Lewis
                                        President and 
                                        Chief Executive Officer

         Pursuant to the requirements of the Securities Exchange Act of 1934,
    this report has been signed below by the following persons on behalf of
    the Registrant and in the capacities indicated below, as of March 17,
    1997.

    Signature                          Title
    ---------                          -----

    By: Earl R. Lewis                  President, Chief Executive Officer,
        -----------------------
        Earl R. Lewis                    and Director

    By: John N. Hatsopoulos            Vice President and Chief Financial
        -----------------------
        John N. Hatsopoulos              Officer

    By: Paul F. Kelleher               Chief Accounting Officer
        -----------------------
        Paul F. Kelleher

    By: George N. Hatsopoulos          Director
        -----------------------
        George N. Hatsopoulos

    By: Stephen R. Levy                Director
        -----------------------
        Stephen R. Levy

    By: Robert A. McCabe               Director
        -----------------------
        Robert A. McCabe

    By: Arvin H. Smith                 Chairman of the Board and Director
        -----------------------
        Arvin H. Smith
                                       13PAGE
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                    Report of Independent Public Accountants
                    ----------------------------------------


    To the Shareholders and Board of Directors of Thermo Optek Corporation:

        We have audited, in accordance with generally accepted auditing
    standards, the consolidated financial statements included in Thermo Optek
    Corporation's Annual Report to Shareholders incorporated by reference in
    this Form 10-K, and have issued our report thereon dated February 11,
    1997. Our audits were made for the purpose of forming an opinion on those
    statements taken as a whole. The schedule listed in Item 14 on page 12 is
    the responsibility of the Company's management and is presented for
    purposes of complying with the Securities and Exchange Commission's rules
    and is not part of the basic consolidated financial statements. This
    schedule has been subjected to the auditing procedures applied in the
    audits of the basic consolidated financial statements and, in our
    opinion, fairly states in all material respects the consolidated
    financial data required to be set forth therein in relation to the basic
    consolidated financial statements taken as a whole.



                                            Arthur Andersen LLP



    Boston, Massachusetts
    February 11, 1997










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SCHEDULE II



                            THERMO OPTEK CORPORATION

                        Valuation and Qualifying Accounts
                                 (In thousands)


                    Balance at  Provision           Accounts            Balance
                     Beginning Charged to  Accounts  Written             at End
                       of Year    Expense Recovered      Off Other (a)     Year
                    ---------- ---------- --------- -------- --------- --------
Year Ended
  December 28, 1996

    Allowance for 
      Doubtful
        Accounts        $5,669     $  907    $  (30) $(2,687)  $  577    $4,436

Year Ended
  December 30, 1995

    Allowance for
      Doubtful
        Accounts        $2,783     $  378    $   32  $  (788)  $3,264    $5,669

Year Ended
  December 31, 1994

    Allowance for
      Doubtful
        Accounts        $2,649     $  521    $   69  $  (373)  $  (83)   $2,783


(a) Includes allowance of businesses acquired during the year as described in
    Note 2 to Consolidated Financial Statements in the Registrant's 1996 Annual
    Report to Shareholders and the effect of foreign currency translation.




                                       15PAGE
<PAGE>
                                  EXHIBIT INDEX

    Exhibit
    Number       Description of Exhibit
    ------------------------------------------------------------------------

       2.1       Stock Purchase Agreement dated as of November 4, 1996,
                 among Thermo Instrument Systems Inc., SID Instruments Inc.,
                 and ATI Acquisition Corp. (filed as Exhibit 2.1 to the
                 Company's Quarterly Report on Form 10-Q for the quarter
                 ended September 28, 1996 [File No. 1-11757] and
                 incorporated herein by reference).

       2.2       Stock Purchase Agreement dated as of November 4, 1996,
                 between Thermo Instrument and the Company (filed as Exhibit
                 2.2 to the Company's Quarterly Report on Form 10-Q for the
                 quarter ended September 28, 1996 [File No. 1-11757] and
                 incorporated herein by reference).

       3.1       Certificate of Incorporation, as amended, of the Company
                 (filed as Exhibit 3.l to the Company's Registration
                 Statement on Form S-1 [Reg. No. 333-03630] and incorporated
                 herein by reference).

       3.2       By-laws of the Company (filed as Exhibit 3.2 to the
                 Company's Registration Statement on Form S-1 [Reg. No.
                 333-03630] and incorporated herein by reference).

      10.1       Corporate Services Agreement dated as of August 18, 1995,
                 between Thermo Electron Corporation and the Company (filed
                 as Exhibit 10.1 to the Company's Registration Statement on
                 Form S-1 [Reg. No. 333-03630] and incorporated herein by
                 reference).

      10.2       Thermo Electron Corporate Charter, as amended and restated
                 effective January 3, 1993 (filed as Exhibit 10.1 to Thermo
                 Electron's Annual Report on Form 10-K for the fiscal year
                 ended January 2, 1993 [File No. 1-8002] and incorporated
                 herein by reference).

      10.3       Tax Allocation Agreement dated as of August 18, 1995,
                 between Thermo Electron and the Company (filed as Exhibit
                 10.3 to the Company's Registration Statement on Form S-1
                 [Reg. No. 333-03630] and incorporated herein by reference).

      10.4       Amended and Restated Master Repurchase Agreement dated as
                 of December 28, 1996, between Thermo Electron and the
                 Company.

      10.5       Master Guarantee Reimbursement Agreement dated as of August
                 18, 1995, between Thermo Electron, Thermo Instrument, and
                 the Company (filed as Exhibit 10.5 to the Company's
                 Registration Statement on Form S-1 [Reg. No. 333-03630] and
                 incorporated herein by reference).

                                       16PAGE
<PAGE>
                                  EXHIBIT INDEX
    Exhibit
    Number       Description of Exhibit
    ------------------------------------------------------------------------

      10.6       Master Guarantee Reimbursement Agreement dated as of August
                 18, 1995, between Thermo Instrument and the Company (filed
                 as Exhibit 10.5A to the Company's Registration Statement on
                 Form S-1 [Reg. No. 333-03630] and incorporated herein by
                 reference).

      10.7       Equity Incentive Plan of the Company (filed as Exhibit 10.6
                 to the Company's Registration Statement on Form S-1 [Reg.
                 No. 333-03630] and incorporated herein by reference).

                 In addition to the stock-based compensation plans of the
                 Registrant, the executive officers of the Registrant may be
                 granted awards under stock-based compensation plans of
                 Thermo Electron and Thermo Instrument for services rendered
                 to the Registrant or such affiliated corporations. Thermo
                 Electron's plans were filed as Exhibits 10.21 through 10.44
                 to the Annual Report on Form 10-K of Thermo Electron for
                 the fiscal year ended December 30, 1995 [File No. 1-8002]
                 and as Exhibit 10.19 to the Annual Report on Form 10-K of
                 Trex Medical Corporation for the fiscal year ended
                 September 28, 1996 [File No. 1-11827], and Thermo
                 Instrument's plans were filed as Exhibits 10.18 through
                 10.27 to the Annual Report on Form 10-K of Thermo
                 Instrument for the fiscal year ended December 28, 1996
                 [File No. 1-9786], and are incorporated herein by
                 reference.

      10.8       Deferred Compensation Plan for Directors of the Company
                 (filed as Exhibit 10.7 to the Company's Registration
                 Statement on Form S-1 [Reg. No. 333-03630] and incorporated
                 herein by reference).

      10.9       Directors Stock Option Plan of the Company (filed as
                 Exhibit 10.8 to the Company's Registration Statement on
                 Form S-1 [Reg. No. 333-03630] and incorporated herein by
                 reference).

      10.10      Form of Indemnification Agreement for Officers and
                 Directors (filed as Exhibit 10.9 to the Company's
                 Registration Statement on Form S-1 [Reg. No. 333-03630] and
                 incorporated herein by reference).

      10.11      Fiscal Agency Agreement dated as of October 12, 1995,
                 between the Company and The Chase Manhattan Bank (formerly
                 Chemical Bank) (filed as Exhibit 10.10 to the Company's
                 Registration Statement on Form S-1 [Reg. No. 333-03630] and
                 incorporated herein by reference).

      10.12      Stock Purchase Agreement dated as of April 11, 1996,
                 between the Company and Thermo Instrument (filed as Exhibit
                 10.11 to the Company's Registration Statement on Form S-1
                 [Reg. No. 333-03630] and incorporated herein by reference).

                                       17PAGE
<PAGE>
                                  EXHIBIT INDEX

    Exhibit
    Number       Description of Exhibit
    ------------------------------------------------------------------------

      10.13      Asset Transfer Agreement dated as of December 31, 1995, by
                 and among the Company, Nicolet Instrument Corporation, and
                 Thermo Instrument (filed as Exhibit 10.12 to the Company's
                 Registration Statement on form S-1 [Reg. No. 333-03630] and
                 incorporated herein by reference).

      10.14      Indemnification Agreement dated as of November 4, 1996,
                 between Thermo Instrument and the Company (filed as Exhibit
                 10.1 to the Company's Quarterly Report on Form 10-Q for the
                 quarter ended September 28, 1996 [File No. 1-11757] and
                 incorporated herein by reference).

      10.15      Restated Stock Holdings Assistance Plan and Form of
                 Promissory Note.

     11          Statement re: Computation of Earnings per Share.

     13          Annual Report to Shareholders for the year ended
                 December 28, 1996 (only those portions incorporated
                 herein by reference).

     21          Subsidiaries of the Registrant.

     23          Consent of Arthur Andersen LLP.

     27          Financial Data Schedule.