SECURITIES AND EXCHANGE COMMISSION

                              Washington, DC 20549

                     ---------------------------------------

                                    FORM 10-Q

    (mark one)

    [ X ] Quarterly Report Pursuant to Section 13 or 15(d) of the Securities
          Exchange Act of 1934 for the Quarter Ended January 3, 1998.

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

                         Commission File Number 1-10791

                             THERMOTREX CORPORATION
             (Exact name of Registrant as specified in its charter)

    Delaware                                                       52-1711436
    (State or other jurisdiction of                          (I.R.S. Employer
    incorporation or organization)                        Identification No.)

    10455 Pacific Center Court
    San Diego, California                                          92121-4339
    (Address of principal executive offices)                       (Zip Code)

       Registrant's telephone number, including area code: (781) 622-1000

           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 such filing
           requirements for the past 90 days. Yes [ X ] No [   ]

           Indicate the number of shares outstanding of each of
           the issuer's classes of Common Stock, as of the
           latest practicable date.

                   Class                 Outstanding at January 30, 1998
        ----------------------------     -------------------------------
        Common Stock, $.01 par value                18,710,376
PAGE
<PAGE>
    PART I - FINANCIAL INFORMATION

    Item 1 - Financial Statements

                             THERMOTREX CORPORATION

                           Consolidated Balance Sheet
                                   (Unaudited)

                                     Assets


                                                   January 3,  September 27,
    (In thousands)                                       1998           1997
    ------------------------------------------------------------------------
    Current Assets:
      Cash and cash equivalents                      $212,918       $135,720
      Available-for-sale investments, at quoted
        market value (amortized cost of $19,145
        and $17,520)                                   19,142         17,499
      Accounts receivable, less allowances of
        $2,066 and $1,969                              69,588         58,632
      Unbilled contract costs and fees                  4,155          4,651
      Inventories:
        Raw materials and supplies                     27,292         27,860
        Work in process                                15,056         13,474
        Finished goods                                  7,236          6,870
      Prepaid expenses                                  4,427          3,422
      Prepaid income taxes                             10,638         11,877
                                                     --------       --------
                                                      370,452        280,005
                                                     --------       --------
    Property, Plant, and Equipment, at Cost            68,233         67,957
      Less: Accumulated depreciation and
            amortization                               15,460         15,568
                                                     --------       --------
                                                       52,773         52,389
                                                     --------       --------
    Notes Receivable from Related Parties (Note 2)      4,967          3,300
                                                     --------       --------
    Prepaid Income Taxes and Other Assets              17,101         13,831
                                                     --------       --------
    Cost in Excess of Net Assets of Acquired
      Companies (Note 5)                              106,748        100,592
                                                     --------       --------
                                                     $552,041       $450,117
                                                     ========       ========

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                             THERMOTREX CORPORATION

                     Consolidated Balance Sheet (continued)
                                   (Unaudited)

                    Liabilities and Shareholders' Investment

                                                   January 3,  September 27,
    (In thousands except share amounts)                  1998           1997
    ------------------------------------------------------------------------
    Current Liabilities:
      Note payable to parent company                 $ 11,000       $ 11,000
      Accounts payable                                 18,823         21,373
      Accrued payroll and employee benefits             7,833          8,863
      Accrued warranty costs                            6,269          6,299
      Accrued commissions                               4,893          3,922
      Other accrued expenses                           26,628         24,245
      Due to parent company and affiliated
        companies                                       1,927          2,027
                                                     --------       --------
                                                       77,373         77,729
                                                     --------       --------
    Long-term Obligations:
      3 1/4% Subordinated convertible debentures
        (Note 3)                                      124,500              -
      4 3/8% Subordinated convertible debentures      115,000        115,000
                                                     --------       --------
                                                      239,500        115,000
                                                     --------       --------
    Deferred Income Taxes                                 346              -
                                                     --------       --------
    Deferred Lease Liability                            1,441          1,379
                                                     --------       --------
    Common Stock of Subsidiary Subject to
      Redemption                                       40,500         40,500
                                                     --------       --------
    Minority Interest                                  40,009         39,374
                                                     --------       --------
    Shareholders' Investment:
      Common stock, $.01 par value, 50,000,000
        shares authorized; 19,347,122 and
        19,251,769 shares issued                          193            193
      Capital in excess of par value                   70,574         78,601
      Retained earnings                                98,954         97,597
      Treasury stock at cost, 711,046 and
        8,747 shares                                  (16,847)          (243)
      Net unrealized loss on available-for-
        sale investments                                   (2)           (13)
                                                     --------       --------
                                                      152,872        176,135
                                                     --------       --------
                                                     $552,041       $450,117
                                                     ========       ========

    The accompanying notes are an integral part of these consolidated
    financial statements.
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                             THERMOTREX CORPORATION

                        Consolidated Statement of Income
                                   (Unaudited)


                                                      Three Months Ended
                                                   -------------------------
                                                   January 3,   December 28,
    (In thousands except per share amounts)              1998           1996
    ------------------------------------------------------------------------
    Revenues                                         $ 85,555       $ 62,826
                                                     --------       --------
    Costs and Operating Expenses:
      Cost of revenues                                 51,865         40,053
      Selling, general, and administrative expenses    20,392         14,864
      Research and development expenses                 9,391          7,370
                                                     --------       --------
                                                       81,648         62,287
                                                     --------       --------
    Operating Income                                    3,907            539

    Interest Income                                     3,271          1,279
    Interest Expense (includes $172 and $30 to
      related party)                                   (2,233)           (30)
    Gain on Issuance of Stock by Subsidiary                 -          1,997
    Equity in Losses of Joint Ventures                   (400)             -
                                                     --------       --------
    Income Before Provision for Income Taxes and
      Minority Interest                                 4,545          3,785
    Provision for Income Taxes                          2,310            977
    Minority Interest Expense                             878             45
                                                     --------       --------
    Net Income                                       $  1,357       $  2,763
                                                     ========       ========

    Basic and Diluted Earnings per Share (Note 4)    $    .07       $    .14
                                                     ========       ========

    Weighted Average Shares (Note 4):
      Basic                                            19,017         19,181
                                                     ========       ========
      Diluted                                          19,313         19,660
                                                     ========       ========


    The accompanying notes are an integral part of these consolidated
    financial statements.

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<PAGE>
                             THERMOTREX CORPORATION

                      Consolidated Statement of Cash Flows
                                   (Unaudited)


                                                      Three Months Ended
                                                   -------------------------
                                                   January 3,   December 28,
    (In thousands)                                       1998           1996
    ------------------------------------------------------------------------
    Operating Activities:
      Net income                                     $  1,357       $  2,763
      Adjustments to reconcile net income to
        net cash used in operating activities:
          Depreciation and amortization                 3,355          1,842
          Provision for losses on accounts
            receivable                                    134            156
          Gain on issuance of stock by subsidiary           -         (1,997)
          Minority interest expense                       878             45
          Increase in long-term prepaid income
            taxes                                      (1,206)             -
          Other                                           572              -
          Changes in current accounts, excluding
            the effects of acquisition:
              Accounts receivable                     (10,829)        (1,763)
              Inventories and unbilled contract
                costs and fees                           (575)        (6,921)
              Other current assets                        253         (1,187)
              Accounts payable                         (2,549)          (743)
              Other current liabilities                 1,926          5,211
                                                     --------       --------
    Net cash used in operating activities              (6,684)        (2,594)
                                                     --------       --------
    Investing Activities:
      Acquisition, net of cash acquired (Note 5)       (7,174)             -
      Purchases of available-for-sale investments      (4,000)             -
      Proceeds from sale and maturities of 
        available-for-sale investments                  2,400         26,500
      Purchases of property, plant, and equipment      (2,584)        (9,530)
      Advance pursuant to note receivable from
        related party (Note 2)                         (1,667)             -
      Other                                               (25)           510
                                                     --------       --------
    Net cash provided by (used in) investing
      activities                                     $(13,050)      $ 17,480
                                                     --------       --------

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                             THERMOTREX CORPORATION

                Consolidated Statement of Cash Flows (continued)
                                   (Unaudited)


                                                      Three Months Ended
                                                   -------------------------
                                                   January 3,   December 28,
    (In thousands)                                       1998           1996
    ------------------------------------------------------------------------
    Financing Activities:
      Net proceeds from issuance of Company and
        subsidiary common stock and sale of
        subsidiary put options                       $    724       $  5,179
      Purchases of Company and subsidiary common
        stock                                         (24,718)        (2,179)
      Net proceeds from issuance of subordinated
        convertible debentures (Note 3)               121,814              -
      Payment of withholding taxes related to
        stock option exercises                           (888)          (523)
                                                     --------       --------
    Net cash provided by financing activities          96,932          2,477
                                                     --------       --------
    Increase in Cash and Cash Equivalents              77,198         17,363
    Cash and Cash Equivalents at Beginning of Period  135,720         43,940
                                                     --------       --------

    Cash and Cash Equivalents at End of Period       $212,918       $ 61,303
                                                     ========       ========

    Noncash Activities:
      Fair value of assets of acquired company       $  7,787       $      -
      Cash paid for acquired company                   (7,176)             -
                                                     --------       --------
        Liabilities assumed of acquired company      $    611       $      -
                                                     ========       ========


    The accompanying notes are an integral part of these consolidated
    financial statements.

                                        6PAGE
<PAGE>
                             THERMOTREX CORPORATION

                   Notes to Consolidated Financial Statements


    1.  General

        The interim consolidated financial statements presented have been
    prepared by ThermoTrex Corporation (the Company) without audit and, in
    the opinion of management, reflect all adjustments of a normal recurring
    nature necessary for a fair statement of the financial position at
    January 3, 1998, and the results of operations and the cash flows for the
    three-month periods ended January 3, 1998, and December 28, 1996. The
    Company's results of operations for the three-month periods ended January
    3, 1998, and December 28, 1996, include 14 weeks and 13 weeks,
    respectively. Interim results are not necessarily indicative of results
    for a full year.

        The consolidated balance sheet presented as of September 27, 1997,
    has been derived from the consolidated financial statements that have
    been audited by the Company's independent public accountants. The
    consolidated financial statements and notes are presented as permitted by
    Form 10-Q and do not contain certain information included in the annual
    financial statements and notes of the Company. The consolidated financial
    statements and notes included herein should be read in conjunction with
    the financial statements and notes included in the Company's Annual
    Report on Form 10-K for the fiscal year ended September 27, 1997, filed
    with the Securities and Exchange Commission.

    2.  Related-party Note Receivable

        In October 1997, the Company's ThermoLase Corporation (ThermoLase)
    subsidiary advanced $1.7 million to ThermoLase U.K. Limited pursuant to a
    note receivable, due December 31, 2003, and bearing interest at 8.0%,
    payable annually. ThermoLase U.K. Limited, a subsidiary of a joint
    venture that is 50%-owned by ThermoLase, is marketing ThermoLase's
    SoftLight system in England.

    3.  Subordinated Convertible Debentures

        In November 1997, the Company issued and sold at par value $124.5
    million principal amount of 3 1/4% subordinated convertible debentures
    due 2007, for net proceeds of $121.8 million. The debentures are
    convertible into shares of the Company's common stock at a conversion
    price of $27.00 per share and are guaranteed on a subordinated basis by
    Thermo Electron Corporation.

    4.  Earnings per Share

        During the first quarter of fiscal 1998, the Company adopted
    Statement of Financial Accounting Standards No. 128, "Earnings per
    Share." As a result, all previously reported earnings per share have been
    restated; however, basic and diluted earnings per share equals the
    Company's previously reported earnings per share for the fiscal 1997
    period. Basic earnings per share have been computed by dividing net
    income by the weighted average number of shares outstanding during the

                                        7PAGE
<PAGE>
                             THERMOTREX CORPORATION

    4.  Earnings per Share (continued)

    period. Diluted earnings per share have been computed assuming the
    exercise of stock options and their related income tax effect. Basic and
    diluted earnings per share were calculated as follows:

                                                     Three Months Ended
                                                  -------------------------
                                                  January 3,   December 28,
    (In thousands except per share amounts)             1998           1996
    -----------------------------------------------------------------------
    Basic
    Net income                                       $ 1,357        $ 2,763
                                                     -------        -------
    Weighted average shares                           19,017         19,181
                                                     -------        -------
    Basic earnings per share                         $   .07        $   .14
                                                     =======        =======

    Diluted
    Net income                                       $ 1,357        $ 2,763
    Effect of majority-owned subsidiaries' 
      dilutive securities                                (18)           (27)
                                                     -------        -------
    Income available to common shareholders, 
      as adjusted                                    $ 1,339        $ 2,736
                                                     -------        -------
    Weighted average shares                           19,017         19,181
    Effect of stock options                              296            479
                                                     -------        -------
    Weighted average shares, as adjusted              19,313         19,660
                                                     -------        -------
    Diluted earnings per share                       $   .07        $   .14
                                                     =======        =======

        The computation of diluted earnings per share excludes the effect of
    assuming the exercise of certain outstanding stock options because the
    effect would be antidilutive. As of January 3, 1998, there were 215,000
    of such options outstanding, with exercise prices ranging from $26.69 to
    $43.88 per share. In addition, the computation of diluted earnings per
    share excludes the effect of assuming the conversion of the Company's
    $124.5 million principal amount of 3 1/4% subordinated convertible
    debentures, convertible at $27.00 per share, because the effect would be
    antidilutive.

    5.  Acquisition

        In October 1997, the Company's Trex Medical Corporation subsidiary
    acquired substantially all of the assets, subject to certain liabilities,
    of Digitec Corporation, a North Carolina-based manufacturer of
    physiological-monitoring equipment and digital-image archiving and
    networking systems used in cardiac catheterization procedures, for
    approximately $7.2 million in cash, subject to a post-closing adjustment.
    To date, no information has been gathered that would cause the Company to

                                        8PAGE
<PAGE>
                             THERMOTREX CORPORATION

    5.  Acquisition (continued)

    believe that such post-closing adjustment will be material. The cost of
    this acquisition exceeded the estimated fair value of the acquired net
    assets by $7.1 million, which is being amortized over 15 years.


    Item 2 - Management's Discussion and Analysis of Financial Condition and
             Results of Operations

        Forward-looking statements, within the meaning of Section 21E of the
    Securities Exchange Act of 1934, are made throughout this Management's
    Discussion and Analysis of Financial Condition and Results of Operations.
    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 heading "Forward-looking Statements"
    in Exhibit 13 to the Company's Annual Report on Form 10-K for the fiscal
    year ended September 27, 1997, filed with the Securities and Exchange
    Commission.

    Overview

        The Company operates in three business segments: Medical Products
    manufactured by the Company's Trex Medical Corporation (Trex Medical)
    subsidiary, Personal-care Products and Services offered by the Company's
    ThermoLase Corporation (ThermoLase) subsidiary, and Advanced Technology
    Research, including the laser communications research performed by the
    Company's Trex Communications Corporation (Trex Communications)
    subsidiary.

        Trex Medical designs, manufactures, and markets mammography equipment
    and minimally invasive digital breast-biopsy systems, general-purpose
    X-ray equipment, and specialized X-ray equipment, including imaging
    systems used during diagnostic and interventional vascular and cardiac
    procedures such as balloon angioplasty. Trex Medical sells its systems
    worldwide principally through a network of independent dealers, and also
    acts as an original equipment manufacturer (OEM) for other medical
    equipment companies. Trex Medical has four operating units: Lorad, a
    manufacturer of mammography and digital breast-biopsy systems; Bennett
    X-Ray Corporation (Bennett), a manufacturer of general-purpose X-ray and
    mammography equipment; XRE Corporation (XRE), a manufacturer of X-ray
    imaging systems used in the diagnosis and treatment of coronary artery
    disease and other vascular conditions; and Continental X-Ray Corporation
    (Continental), a manufacturer of general-purpose and specialized X-ray
    systems.

                                        9PAGE
<PAGE>
                             THERMOTREX CORPORATION

    Overview (continued)

        ThermoLase has developed a laser-based system called SoftLight(R) for
    the removal of unwanted hair. The SoftLight system uses a low-energy,
    dermatology laser in combination with a lotion that absorbs the laser's
    energy to disable hair follicles. In April 1995, the Company received
    clearance from the U.S. Food and Drug Administration (FDA) to
    commercially market hair-removal services using the SoftLight system.
    ThermoLase began earning revenue from the SoftLight system in the first
    quarter of fiscal 1996 as a result of opening its first commercial
    location (Spa Thira) in November 1995. ThermoLase opened a total of four
    spas during fiscal 1996, opened nine additional spas during fiscal 1997,
    and, by January 3, 1998, had a total of 14 domestic Spa Thira locations.
    Rather than continuing to open additional domestic Spa Thira locations,
    ThermoLase presently intends to concentrate its resources on attempting
    both to increase the capacity utilization of its existing U.S. spas and
    to expand its physicians' licensing program and international licensing
    arrangements, discussed below. In June 1996, ThermoLase commenced a
    program to license to physicians and others the right to perform the
    Company's patented SoftLight hair-removal procedure. In this program,
    ThermoLase licenses its technology and receives a one-time fee and a
    per-procedure royalty that varies depending on the anatomical site
    treated and pricing plan selected by the client. ThermoLase also provides
    the licensees with the lasers and lotion that are necessary to perform
    the service. ThermoLase is marketing the SoftLight system internationally
    through joint ventures and other licensing arrangements. In January 1996,
    ThermoLase established a joint venture in Japan. During fiscal 1997,
    ThermoLase established joint ventures in France in November 1996 and
    England in September 1997, and six additional licensing arrangements: in
    Saudi Arabia in November 1996; in Tunisia and Belgium in December 1996;
    in the United Arab Emirates and Oman in March 1997; in Switzerland in
    April 1997; in Brazil in June 1997; and in the United Kingdom (excluding
    England) and the Republic of Ireland in September 1997. In December 1997,
    the Company established a joint venture to market the SoftLight system in
    Australia, Cyprus, Germany, Greece, New Zealand, South Africa, and Spain.
    ThermoLase's international arrangements resulted in the opening of spas
    in Paris in May 1997 and in Lugano, Switzerland, in October 1997.

        In September 1997, ThermoLase introduced a modification to its
    hair-removal treatment, called SoftLight 2.0. Although clinical
    laboratory results were encouraging, ThermoLase has determined that
    further modification is warranted, and accordingly continues to adjust
    its treatment protocol. ThermoLase plans to continue research and
    development as it seeks to improve the efficacy and duration of its
    hair-removal treatment, and believes that such improvements are critical
    elements in its ability to improve the profitability of its business.

        In March 1997, ThermoLase filed with the FDA a 510(k) application
    seeking clearance to market cosmetic skin-resurfacing services utilizing
    its SoftLight Rejuvenation(TM) Laser, including wrinkle and skin-texture
    treatment. This technology, which uses the same laser as ThermoLase's
    hair-removal system, is designed to improve the skin's appearance and
    texture. Following discussions with the FDA in December 1997, ThermoLase

                                       10PAGE
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                             THERMOTREX CORPORATION

    Overview (continued)

    has decided to submit additional data and to focus on claims related to
    skin texture rather than wrinkle treatment, in order to expedite
    clearance of the application.

        ThermoLase also manufactures and markets skin-care, bath, and body
    products through its CBI Laboratories, Inc. (CBI) subsidiary, which also
    manufactures the lotion used in the SoftLight hair-removal process.

        The Company's Advanced Technology Research segment performs research
    primarily in the fields of communications, avionics, X-ray detection,
    signal processing, and lasers. The Company has developed its expertise in
    these core technologies in connection with government-sponsored research
    and development. The Advanced Technology Research segment includes the
    Company's Trex Communications subsidiary, which is developing a laser
    communications (lasercom) technology, designed to move very large amounts
    of data quickly via lasers without the need for wires or licensing from
    the Federal Communications Commission. In addition, Trex Communications'
    Computer Communications Specialists, Inc. (CCS) subsidiary designs and
    markets interactive information and voice-response systems, as well as
    call-automation systems.

        The Company conducts all of its manufacturing operations in the
    United States and distributes its products, services, and technologies
    worldwide. The Company anticipates that an increasing portion of its
    revenues will be from international sales. The Company's international
    sales are generally denominated in U.S. dollars; however, the Company's
    financial performance and competitive position can be affected by
    currency exchange rate fluctuations affecting the relationship between
    the U.S. dollar and foreign currencies.

    Results of Operations

    First Quarter Fiscal 1998 Compared With First Quarter Fiscal 1997

        Total revenues increased 36% to $85.6 million in the first quarter of
    fiscal 1998 from $62.8 million in the first quarter of fiscal 1997.
    Medical Products segment revenues, excluding intersegment sales,
    increased 25% to $63.8 million in fiscal 1998 from $51.0 million in
    fiscal 1997, primarily due to increased sales at all of Trex Medical's
    existing operations. Sales increased at Lorad due to increased demand for
    breast-biopsy systems, mammography system upgrade components, and mobile
    X-ray systems. Sales also increased due to increased demand for XRE's
    catheterization labs and Bennett's mammography systems, and due to the
    inclusion of $1.5 million of revenues as a result of the acquisition of
    Digitec Corporation (Digitec) in October 1997 (Note 5).

        Personal-care Products and Services segment revenues increased 56% to
    $13.4 million in the first quarter of fiscal 1998 from $8.6 million in
    the first quarter of fiscal 1997. ThermoLase earned revenues from
    hair-removal services and related activities of $7.0 million in fiscal
    1998, compared with $2.6 million in fiscal 1997. The increase in revenues
    resulted in part from an increase in the number of U.S. spas to 14,

                                       11PAGE
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                             THERMOTREX CORPORATION

    First Quarter Fiscal 1998 Compared With First Quarter Fiscal 1997
    (continued)

    compared with seven spas open during fiscal 1997. ThermoLase changed its
    pricing plan in March 1997 to offer single or multiple treatment plans,
    and continues to evaluate its pricing plans. ThermoLase defers revenue
    related to payments for multiple treatment plans, which is recognized
    over the anticipated treatment period. As ThermoLase collects further
    data concerning the number of treatments required and duration of the
    treatment period, the period of revenue recognition may be affected.
    Revenues from ThermoLase's physicians' licensing program also increased
    in fiscal 1998, primarily due to an increase in the number of
    physician-licensees. In addition, revenues from hair-removal services and
    related activities in fiscal 1998 included $2.8 million of minimum
    guaranteed payments recorded upon granting technology rights under
    ThermoLase's international licensing arrangements, compared with
    $0.3 million in fiscal 1997. Of the $2.8 million earned in fiscal 1998,
    $0.5 million was due upon the grant of the technology rights during the
    quarter, and the balance of $2.3 million is due on March 2, 1998. The
    amount of minimum guaranteed payments recorded by ThermoLase will vary
    depending on its ability to enter into additional international licensing
    arrangements, the availability of additional territories, and the terms
    of any such arrangements. Revenues at CBI increased to $6.4 million in
    fiscal 1998 from $6.0 million in fiscal 1997. A portion of CBI's revenues
    are derived from sales to large retailers, which have a relatively long
    buying cycle that results in periodic variations in revenues.

        Advanced Technology Research segment revenues, excluding intersegment
    sales, increased to $8.4 million in the first quarter of fiscal 1998 from
    $3.2 million in the first quarter of fiscal 1997. Revenues increased $4.1
    million due to the inclusion of product revenues from CCS, acquired in
    July 1997.

        The gross profit margin was 39% in the first quarter of fiscal 1998,
    compared with 36% in the first quarter of fiscal 1997. The Medical
    Products segment gross profit margin, excluding intersegment sales,
    increased to 42% in fiscal 1998 from 39% in fiscal 1997, primarily due to
    an increase in higher-margin direct sales at XRE and margin improvements
    on certain products at Lorad. To a lesser extent, the gross profit margin
    at Trex Medical increased due to the inclusion of higher-margin revenues
    at Digitec and margin improvements at Continental and Bennett. The
    Personal-care Products and Services segment gross profit margin was 26%
    in fiscal 1998, compared with 21% in fiscal 1997. ThermoLase's
    hair-removal business reported gross profit of $1.4 million in fiscal
    1998, compared with gross profit of negative $0.2 million in fiscal 1997.
    Each period was impacted by the early operations of the Spa Thira
    business, which has been operating below maximum capacity as ThermoLase
    seeks to develop its client base and refine its process and operating
    procedures, offset in part by the effect of physicians' licensing fees
    and minimum guaranteed payments relating to international licensing
    arrangements, which have a relatively high gross profit margin. In
    addition, fiscal 1997 was negatively impacted by pre-opening costs
    incurred in connection with new spa openings. During the remainder of
    fiscal 1998, the effect of operating each spa below maximum capacity, as

                                       12PAGE
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                             THERMOTREX CORPORATION

    First Quarter Fiscal 1998 Compared With First Quarter Fiscal 1997
    (continued)

    ThermoLase seeks to develop its client base and expand its product lines,
    will continue to have a negative impact on its gross profit margin.
    ThermoLase believes that improvements in the efficacy and duration of the
    SoftLight process are critical elements in its ability to improve the
    profitability of its spas. In December 1997, ThermoLase began introducing
    traditional day spa services, such as European facials and massages, in
    an effort to improve the capacity utilization of its spas. The increase
    in gross profit from ThermoLase's hair-removal business was offset in
    part by a decrease in the gross profit margin at CBI, due to a continued
    shift to lower-margin products.

        Selling, general, and administrative expenses as a percentage of
    revenues was 24% in both periods. Research and development expenses
    increased to $9.4 million in the first quarter of fiscal 1998 from $7.4
    million in the first quarter of fiscal 1997, primarily due to increased
    spending at Trex Medical and the inclusion of $0.6 million of expense at
    CCS, acquired in July 1997. Trex Medical's increase in spending,
    primarily at XRE and Lorad, reflects its continued efforts to develop and
    commercialize new products, including the full-field digital mammography
    system and direct-detection X-ray sensor, as well as enhancements of
    existing systems. Research and development expenses at ThermoLase were
    $0.9 million in both periods. ThermoLase plans to continue research and
    development as it seeks to improve the efficacy and duration of its
    hair-removal treatment. In addition, ThermoLase continues to develop its
    SoftLight Rejuvenation Laser skin treatment and investigate other health
    and beauty applications for its proprietary laser technology.
 
        Interest income increased to $3.3 million in the first quarter of
    fiscal 1998 from $1.3 million in the first quarter of fiscal 1997,
    primarily due to interest income earned on the invested proceeds from the
    Company's November 1997 issuance of $124.5 million principal amount of 
    3 1/4% subordinated convertible debentures (Note 3) and ThermoLase's
    August 1997 issuance of $115.0 million principal amount of 4 3/8%
    subordinated convertible debentures. Interest expense increased to $2.2
    million in fiscal 1998 from $30,000 in fiscal 1997, primarily due to the
    issuance of these debentures.

        During the first quarter of fiscal 1997, the Company recorded a gain
    of $2.0 million from the issuance of stock by subsidiary in connection
    with a private placement of Trex Medical common stock.

        Equity in losses of joint ventures in the accompanying statement of
    income represents ThermoLase's proportionate share of losses from its
    international joint ventures.

        Minority interest expense increased to $0.9 million in the first
    quarter of fiscal 1998 from $45,000 in the first quarter of fiscal 1997,
    primarily due to the Company's inability to record minority interest
    income in ThermoLase's net loss, because the Company's minority interest
    liability related to ThermoLase has been reduced to zero. In addition,
    minority interest expense increased in fiscal 1998 due to an increase in
    Trex Medical's net income.

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                             THERMOTREX CORPORATION

    First Quarter Fiscal 1998 Compared With First Quarter Fiscal 1997
    (continued)

        The effective tax rate exceeded the statutory federal income tax rate
    in the first quarter of fiscal 1998 primarily due to the impact of state
    income taxes and nondeductible amortization of cost in excess of net
    assets of acquired companies. The effective tax rate was below the
    statutory federal income tax rate in the first quarter of fiscal 1997
    primarily due to a nontaxable gain on the issuance of stock by
    subsidiary, offset in part by the impact of state income taxes and
    nondeductible amortization of cost in excess of net assets of acquired
    companies.

    Liquidity and Capital Resources

        Consolidated working capital was $293.1 million at January 3, 1998,
    compared with $202.3 million at September 27, 1997. Included in working
    capital are cash, cash equivalents, and available-for-sale investments of
    $232.1 million at January 3, 1998, compared with $153.2 million at
    September 27, 1997. Of the $232.1 million balance at January 3, 1998,
    $117.8 million was held by the Company's majority-owned subsidiaries, and
    the remainder was held by the Company and its wholly owned subsidiary.

        Net cash used in operating activities during the first quarter of
    fiscal 1998 was $6.7 million. An increase in accounts receivable,
    primarily at Trex Medical, used $10.8 million in cash. The increase in
    accounts receivable at Trex Medical was primarily due to increased sales
    and, to a lesser extent, longer customer payment patterns as a result of
    increased export sales at Bennett and a shift from OEM sales to direct
    sales at XRE.

        Excluding available-for-sale investments activity, the Company's
    primary investing activities during the first quarter of fiscal 1998
    included capital expenditures and an acquisition. The Company expended
    $2.6 million for property, plant, and equipment and $7.2 million, net of
    cash acquired, for the acquisition of Digitec (Note 5).

        In connection with certain of ThermoLase's joint venture
    arrangements, ThermoLase provided funding of $1.7 million during the
    first quarter of fiscal 1998 (Note 2). ThermoLase has agreed to provide
    additional funding of up to approximately $5.4 million under these
    arrangements.

        The Company's financing activities provided $96.9 million of cash
    during the first quarter of fiscal 1998. In November 1997, the Company
    sold at par value $124.5 million principal amount of 3 1/4% subordinated
    convertible debentures due 2007 for net proceeds of $121.8 million
    (Note 3).

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                             THERMOTREX CORPORATION

    Liquidity and Capital Resources (continued)

        In September 1997, ThermoLase's Board of Directors authorized the
    repurchase by ThermoLase of up to 1,000,000 shares of its common stock
    through September 4, 1998, in the open market, in negotiated
    transactions, or pursuant to the exercise by investors of standardized
    put options written on its common stock. During the first quarter of
    fiscal 1998, ThermoLase repurchased 643,000 shares of its common stock
    for $8.8 million. As of January 3, 1998, authorization to repurchase up
    to an additional 1,016 shares remained outstanding.

        In November 1997, the Company's Board of Directors authorized the
    repurchase by the Company of up to $20.0 million of its common stock,
    through November 1998, in the open market or in negotiated transactions.
    During the first quarter of fiscal 1998, the Company repurchased 672,162
    shares of its common stock for $15.9 million.

        In January 1998, Trex Medical filed a registration statement under
    the Securities Act of 1933 with the Securities and Exchange Commission
    for a public offering by Trex Medical of 4,500,000 shares of its common
    stock. In addition, the underwriters are expected to be granted a 30-day
    over-allotment option to purchase an additional 675,000 shares. There can
    be no assurance that this offering will be completed.

        In December 1997, Trex Medical signed a nonbinding letter of intent
    to acquire Trophy Radiologie (Trophy), a Paris, France-based manufacturer
    of dental X-ray systems specializing in digital technology. The proposed
    acquisition is subject to certain conditions including completion of due
    diligence and approval by the boards of directors of Trex Medical and
    Trophy. The final terms of such acquisition have not been determined and
    there can be no assurance that it will be completed.

        ThermoLase's capital expenditures during the remainder of fiscal 1998
    will primarily be affected by the number of physicians and other domestic
    and international licensees engaged in its licensing programs. In
    addition to expenditures by ThermoLase, the Company plans to make capital
    additions of approximately $7.5 million for its other businesses during
    the remainder of fiscal 1998. The Company expects that it will finance
    growth at its majority-owned and wholly owned subsidiaries through a
    combination of internal funds, additional debt or equity financing,
    and/or short-term borrowings from Thermo Electron, although it has no
    agreement to ensure that funds will be available from Thermo Electron on
    acceptable terms or at all. The Company believes its existing resources
    are sufficient to meet the capital requirements of its existing
    operations for the foreseeable future.

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                             THERMOTREX CORPORATION

    PART II - OTHER INFORMATION

    Item 6 - Exhibits and Reports on Form 8-K

    (a) Exhibits

        See Exhibit Index on the page immediately preceding exhibits.

    (b) Reports on Form 8-K

        On October 10, 1997, the Company filed a Current Report on Form 8-K,
    with respect to a press release issued that day, related to its estimated
    earnings for the period ended September 27, 1997.

        On October 10, 1997, the Company filed a Current Report on Form 8-K,
    with respect to the sale of $124.5 million principal amount of 3 1/4%
    subordinated convertible debentures due 2007. On October 29, 1997, the
    Company filed a Current Report on Form 8-K, with respect to the pricing
    of these debentures.

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                             THERMOTREX CORPORATION

                                   SIGNATURES


        Pursuant to the requirements 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 as of the 9th day of February
    1998.

                                           THERMOTREX CORPORATION



                                           /s/ Paul F. Kelleher
                                           ---------------------------
                                           Paul F. Kelleher
                                           Chief Accounting Officer



                                           /s/ John N. Hatsopoulos
                                           ---------------------------
                                           John N. Hatsopoulos
                                           Chief Financial Officer and
                                             Senior Vice President

                                       17PAGE
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                             THERMOTREX CORPORATION

                                  EXHIBIT INDEX


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

     10.1         Amended and Restated Guarantee and Loan Agreement dated
                  December 12, 1997, between the Company and Thermo Electron
                  Corporation.

     10.2         Amended and Restated Guarantee and Loan Agreement dated
                  December 12, 1997, between ThermoLase Corporation and
                  Thermo Electron Corporation (incorporated by reference from
                  Exhibit 10.2 to ThermoLase Corporation's Quarterly Report
                  on Form 10-Q for the quarter ended January 3, 1998 [File
                  No. 1-13104]).

     10.3         Amended and Restated Guarantee and Loan Agreement dated
                  December 12, 1997, between Trex Medical Corporation and
                  Thermo Electron Corporation (incorporated by reference from
                  Exhibit 10.1 to Trex Medical Corporation's Quarterly Report
                  on Form 10-Q for the quarter ended January 3, 1998 [File
                  No. 1-11827]).

     27           Financial Data Schedule.