TREX MEDICAL CORPORATION

                              EQUITY INCENTIVE PLAN

                    As amended and restated effective as of June 18, 1999


1.      Purpose

        The purpose of this Equity Incentive Plan (the "Plan") is to secure for
Trex Medical Corporation (the "Company") and its Stockholders the benefits
arising from capital stock ownership by employees and Directors of, and
consultants to, the Company and its subsidiaries or other persons who are
expected to make significant contributions to the future growth and success of
the Company and its subsidiaries. The Plan is intended to accomplish these goals
by enabling the Company to offer such persons equity-based interests,
equity-based incentives or performance-based stock incentives in the Company, or
any combination thereof ("Awards").

2.      Administration

        The Plan will be administered by the Board of Directors of the Company
(the "Board"). The Board shall have full power to interpret and administer the
Plan, to prescribe, amend and rescind rules and regulations relating to the Plan
and Awards, and full authority to select the persons to whom Awards will be
granted ("Participants"), determine the type and amount of Awards to be granted
to Participants (including any combination of Awards), determine the terms and
conditions of Awards granted under the Plan (including terms and conditions
relating to events of merger, consolidation, dissolution and liquidation, change
of control, vesting, forfeiture, restrictions, dividends and interest, if any,
on deferred amounts), waive compliance by a participant with any obligation to
be performed by him or her under an Award, waive any term or condition of an
Award, cancel an existing Award in whole or in part with the consent of a
Participant, grant replacement Awards, accelerate the vesting or lapse of any
restrictions of any Award and adopt the form of instruments evidencing Awards
under the Plan and change such forms from time to time. Any interpretation by
the Board of the terms and provisions of the Plan or any Award thereunder and
the administration thereof, and all action taken by the Board, shall be final,
binding and conclusive on all parties and any person claiming under or through
any party. No Director shall be liable for any action or determination made in
good faith. The Board may, to the full extent permitted by law, delegate any or
all of its responsibilities under the Plan to a committee (the "Committee")
appointed by the Board and consisting of two or more members of the Board, each
of whom shall be deemed a "disinterested person" within the meaning of Rule
16b-3 (or any successor rule) of the Securities Exchange Act of 1934 (the
"Exchange Act").

3.      Effective Date

        The Plan shall be effective as of the date first approved by the Board
of Directors, subject to the approval of the Plan by the Corporation's
Stockholders. Grants of Awards under the Plan made prior to such approval shall
be effective when made (unless otherwise specified by the Board at the time of
grant), but shall be conditioned on and subject to such approval of the Plan.

4.      Shares Subject to the Plan

        Subject to adjustment as provided in Section 10.6, the total number of
shares of Common Stock reserved and available for distribution under the Plan
shall be 2,200,000 shares. Such shares may consist, in whole or in part, of
authorized and unissued shares or treasury shares.

        If any Award of shares of Common Stock requiring exercise by the
Participant for delivery of such shares terminates without having been exercised
in full, is forfeited or is otherwise terminated without a payment being made to
the Participant in the form of Common Stock, or if any shares of Common Stock
subject to restrictions are repurchased by the Company pursuant to the terms of
any Award or are otherwise reacquired by the Company to satisfy obligations
arising by virtue of any Award, such shares shall be available for distribution
in connection with future Awards under the Plan.

5.      Eligibility

        Employees and Directors of, and consultants to, the Company and its
subsidiaries, or other persons who are expected to make significant
contributions to the future growth and success of the Company and its
subsidiaries shall be eligible to receive Awards under the Plan. The Board, or
other appropriate committee or person to the extent permitted pursuant to the
last sentence of Section 2, shall from time to time select from among such
eligible persons those who will receive Awards under the Plan.

6.      Types of Awards

        The Board may offer Awards under the Plan in any form of equity-based
interest, equity-based incentive or performance-based stock incentive in Common
Stock of the Company or any combination thereof. The type, terms and conditions
and restrictions of an Award shall be determined by the Board at the time such
Award is made to a Participant; provided however that the maximum number of
shares permitted to be granted under any Award or combination of Awards to any
Participant during any one calendar year may not exceed 500,000 shares of Common
Stock.

        An Award shall be made at the time specified by the Board and shall be
subject to such conditions or restrictions as may be imposed by the Board and
shall conform to the general rules applicable under the Plan as well as any
special rules then applicable under federal tax laws or regulations or the
federal securities laws relating to the type of Award granted.

        Without limiting the foregoing, Awards may take the following forms and
shall be subject to the following rules and conditions:

        6.1    Options

        An option is an Award that entitles the holder on exercise thereof to
purchase Common Stock at a specified exercise price. Options granted under the
Plan may be either incentive stock options ("incentive stock options") that meet
the requirements of Section 422 of the Internal Revenue Code of 1986, as amended
(the "Code"), or options that are not intended to meet the requirements of
Section 422 ("non-statutory options").

        6.1.1 Option Price. The price at which Common Stock may be purchased
upon exercise of an option shall be determined by the Board, provided however,
the exercise price shall not be less than the par value per share of Common
Stock.

        6.1.2 Option Grants. The granting of an option shall take place at the
time specified by the Board. Options shall be evidenced by option agreements.
Such agreements shall conform to the requirements of the Plan, and may contain
such other provisions (including but not limited to vesting and forfeiture
provisions, acceleration, change of control, protection in the event of merger,
consolidations, dissolutions and liquidations) as the Board shall deem
advisable. Option agreements shall expressly state whether an option grant is
intended to qualify as an incentive stock option or non-statutory option.

        6.1.3 Option Period. An option will become exercisable at such time or
times (which may be immediately or in such installments as the Board shall
determine) and on such terms and conditions as the Board shall specify. The
option agreements shall specify the terms and conditions applicable in the event
of an option holder's termination of employment during the option's term.

        Any exercise of an option must be in writing, signed by the proper
person and delivered or mailed to the Company, accompanied by (1) any additional
documents required by the Board and (2) payment in full in accordance with
Section 6.1.4 for the number of shares for which the option is exercised.

        6.1.4 Payment of Exercise Price. Stock purchased on exercise of an
option shall be paid for as follows: (1) in cash or by check (subject to such
guidelines as the Company may establish for this purpose), bank draft or money
order payable to the order of the Company or (2) if so permitted by the
instrument evidencing the option (or in the case of a non-statutory option, by
the Board at or after grant of the option), (i) through the delivery of shares
of Common Stock that have been outstanding for at least six months (unless the
Board expressly approves a shorter period) and that have a fair market value
(determined in accordance with procedures prescribed by the Board) equal to the
exercise price, (ii) by delivery of a promissory note of the option holder to
the Company, payable on such terms as are specified by the Board, (iii) by
delivery of an unconditional and irrevocable undertaking by a broker to deliver
promptly to the Company sufficient funds to pay the exercise price, or (iv) by
any combination of the permissible forms of payment.

        6.1.5 Buyout Provision. The Board may at any time offer to buy out for a
payment in cash, shares of Common Stock, deferred stock or restricted stock, an
option previously granted, based on such terms and conditions as the Board shall
establish and communicate to the option holder at the time that such offer is
made.

        6.1.6 Special Rules for Incentive Stock Options. Each provision of the
Plan and each option agreement evidencing an incentive stock option shall be
construed so that each incentive stock option shall be an incentive stock option
as defined in Section 422 of the Code or any statutory provision that may
replace such Section, and any provisions thereof that cannot be so construed
shall be disregarded. Instruments evidencing incentive stock options must
contain such provisions as are required under applicable provisions of the Code.
Incentive stock options may be granted only to employees of the Company and its
subsidiaries. The exercise price of an incentive stock option shall not be less
than 100% (110% in the case of an incentive stock option granted to a more than
ten percent Stockholder of the Company) of the fair market value of the Common
Stock on the date of grant, as determined by the Board. An incentive stock
option may not be granted after the tenth anniversary of the date on which the
Plan was adopted by the Board and the latest date on which an incentive stock
option may be exercised shall be the tenth anniversary (fifth anniversary, in
the case of any incentive stock option granted to a more than ten percent
Stockholder of the Company) of the date of grant, as determined by the Board.

        6.2    Restricted and Unrestricted Stock

        An Award of restricted stock entitles the recipient thereof to acquire
shares of Common Stock upon payment of the purchase price subject to
restrictions specified in the instrument evidencing the Award.

        6.2.1 Restricted Stock Awards. Awards of restricted stock shall be
evidenced by restricted stock agreements. Such agreements shall conform to the
requirements of the Plan, and may contain such other provisions (including
restriction and forfeiture provisions, change of control, protection in the
event of mergers, consolidations, dissolutions and liquidations) as the Board
shall deem advisable.

        6.2.2 Restrictions. Until the restrictions specified in a restricted
stock agreement shall lapse, restricted stock may not be sold, assigned,
transferred, pledged or otherwise encumbered or disposed of, and upon certain
conditions specified in the restricted stock agreement, must be resold to the
Company for the price, if any, specified in such agreement. The restrictions
shall lapse at such time or times, and on such conditions, as the Board may
specify. The Board may at any time accelerate the time at which the restrictions
on all or any part of the shares shall lapse.

        6.2.3 Rights as a Stockholder. A Participant who acquires shares of
restricted stock will have all of the rights of a Stockholder with respect to
such shares including the right to receive dividends and to vote such shares.
Unless the Board otherwise determines, certificates evidencing shares of
restricted stock will remain in the possession of the Company until such shares
are free of all restrictions under the Plan.

        6.2.4 Purchase Price. The purchase price of shares of restricted stock
shall be determined by the Board, in its sole discretion, but such price may not
be less than the par value of such shares.

        6.2.5 Other Awards Settled With Restricted Stock. The Board may provide
that any or all the Common Stock delivered pursuant to an Award will be
restricted stock.

        6.2.6 Unrestricted Stock. The Board may, in its sole discretion, sell to
any Participant shares of Common Stock free of restrictions under the Plan for a
price determined by the Board, but which may not be less than the par value per
share of the Common Stock.

        6.3    Deferred Stock

        6.3.1 Deferred Stock Award. A deferred stock Award entitles the
recipient to receive shares of deferred stock, which is Common Stock to be
delivered in the future. Delivery of the Common Stock will take place at such
time or times, and on such conditions, as the Board may specify. The Board may
at any time accelerate the time at which delivery of all or any part of the
Common Stock will take place.

        6.3.2 Other Awards Settled with Deferred Stock. The Board may, at the
time any Award described in this Section 6 is granted, provide that, at the time
Common Stock would otherwise be delivered pursuant to the Award, the Participant
will instead receive an instrument evidencing the right to future delivery of
deferred stock.

        6.4    Performance Awards

        6.4.1 Performance Awards. A performance Award entitles the recipient to
receive, without payment, an amount, in cash or Common Stock or a combination
thereof (such form to be determined by the Board), following the attainment of
performance goals. Performance goals may be related to personal performance,
corporate performance, departmental performance or any other category of
performance deemed by the Board to be important to the success of the Company.
The Board will determine the performance goals, the period or periods during
which performance is to be measured and all other terms and conditions
applicable to the Award.

        6.4.2 Other Awards Subject to Performance Conditions. The Board may, at
the time any Award described in this Section 6 is granted, impose the condition
(in addition to any conditions specified or authorized in this Section 6 of the
Plan) that performance goals be met prior to the Participant's realization of
any payment or benefit under the Award.

7.      Purchase Price and Payment

        Except as otherwise provided in the Plan, the purchase price of Common
Stock to be acquired pursuant to an Award shall be the price determined by the
Board, provided that such price shall not be less than the par value of the
Common Stock. Except as otherwise provided in the Plan, the Board may determine
the method of payment of the exercise price or purchase price of an Award
granted under the Plan and the form of payment. The Board may determine that all
or any part of the purchase price of Common Stock pursuant to an Award has been
satisfied by past services rendered by the Participant. The Board may agree at
any time, upon request of the Participant, to defer the date on which any
payment under an Award will be made.

8.      Loans and Supplemental Grants

        The Company may make a loan to a Participant, either on or after the
grant to the Participant of any Award, in connection with the purchase of Common
Stock under the Award or with the payment of any obligation incurred or
recognized as a result of the Award. The Board will have full authority to
decide whether the loan is to be secured or unsecured or with or without
recourse against the borrower, the terms on which the loan is to be repaid and
the conditions, if any, under which it may be forgiven.

        In connection with any Award, the Board may at the time such Award is
made or at a later date, provide for and make a cash payment to the participant
not to exceed an amount equal to (a) the amount of any federal, state and local
income tax or ordinary income for which the Participant will be liable with
respect to the Award, plus (b) an additional amount on a grossed-up basis
necessary to make him or her whole after tax, discharging all the participant's
income tax liabilities arising from all payments under the Plan.

9.      Change in Control

        9.1    Impact of Event

        In the event of a "Change in Control" as defined in Section 9.2, the
following provisions shall apply, unless the agreement evidencing the Award
otherwise provides (by specific explicit reference to Section 9.2 below). If a
Change in Control occurs while any Awards are outstanding, then, effective upon
the Change in Control, (i) each outstanding stock option or other stock-based
Award awarded under the Plan that was not previously exercisable and vested
shall become immediately exercisable in full and will no longer be subject to a
right of repurchase by the Company, (ii) each outstanding restricted stock award
or other stock-based Award subject to restrictions and to the extent not fully
vested, shall be deemed to be fully vested, free of restrictions and no longer
subject to a right of repurchase by the Company, and (iii) deferral limitations
and conditions that relate solely to the passage of time, continued employment
or affiliation will be waived and removed as to deferred stock Awards and
performance Awards; performance of other conditions (other than conditions
relating solely to the passage of time, continued employment or affiliation)
will continue to apply unless otherwise provided in the agreement evidencing the
Award or in any other agreement between the Participant and the Company or
unless otherwise agreed by the Board.

        9.2    Definition of "Change in Control"

        "Change in Control" means an event or occurrence set forth in any one or
more of subsections (a) through (d) below (including an event or occurrence that
constitutes a Change in Control under one of such subsections but is
specifically exempted from another such subsection):

        (a) the acquisition by an individual, entity or group (within the
meaning of Section 13(d)(3) or 14(d)(2) of the Exchange Act) (a "Person") of
beneficial ownership of any capital stock of Thermo Electron Corporation
("Thermo Electron") if, after such acquisition, such Person beneficially owns
(within the meaning of Rule 13d-3 promulgated under the Exchange Act) 40% or
more of either (i) the then-outstanding shares of common stock of Thermo
Electron (the "Outstanding TMO Common Stock") or (ii) the combined voting power
of the then-outstanding securities of Thermo Electron entitled to vote generally
in the election of directors (the "Outstanding TMO Voting Securities");
provided, however, that for purposes of this subsection (a), the following
acquisitions shall not constitute a Change in Control: (i) any acquisition by
Thermo Electron, (ii) any acquisition by any employee benefit plan (or related
trust) sponsored or maintained by Thermo Electron or any corporation controlled
by Thermo Electron, or (iii) any acquisition by any corporation pursuant to a
transaction which complies with clauses (i) and (ii) of subsection (c) of this
definition; or

        (b) such time as the Continuing Directors (as defined below) do not
constitute a majority of the Board of Directors of Thermo Electron (the "Thermo
Board") (or, if applicable, the Board of Directors of a successor corporation to
Thermo Electron), where the term "Continuing Director" means at any date a
member of the Thermo Board (i) who was a member of the Thermo Board as of July
1, 1999 or (ii) who was nominated or elected subsequent to such date by at least
a majority of the directors who were Continuing Directors at the time of such
nomination or election or whose election to the Thermo Board was recommended or
endorsed by at least a majority of the directors who were Continuing Directors
at the time of such nomination or election; provided, however, that there shall
be excluded from this clause (ii) any individual whose initial assumption of
office occurred as a result of an actual or threatened election contest with
respect to the election or removal of directors or other actual or threatened
solicitation of proxies or consents, by or on behalf of a person other than the
Thermo Board; or

        (c) the consummation of a merger, consolidation, reorganization,
recapitalization or statutory share exchange involving Thermo Electron or a sale
or other disposition of all or substantially all of the assets of Thermo
Electron in one or a series of transactions (a "Business Combination"), unless,
immediately following such Business Combination, each of the following two
conditions is satisfied: (i) all or substantially all of the individuals and
entities who were the beneficial owners of the Outstanding TMO Common Stock and
Outstanding TMO Voting Securities immediately prior to such Business Combination
beneficially own, directly or indirectly, more than 60% of the then-outstanding
shares of common stock and the combined voting power of the then-outstanding
securities entitled to vote generally in the election of directors,
respectively, of the resulting or acquiring corporation in such Business
Combination (which shall include, without limitation, a corporation which as a
result of such transaction owns Thermo Electron or substantially all of Thermo
Electron's assets either directly or through one or more subsidiaries) (such
resulting or acquiring corporation is referred to herein as the "Acquiring
Corporation") in substantially the same proportions as their ownership,
immediately prior to such Business Combination, of the Outstanding TMO Common
Stock and Outstanding TMO Voting Securities, respectively; and (ii) no Person
(excluding the Acquiring Corporation or any employee benefit plan (or related
trust) maintained or sponsored by Thermo Electron or by the Acquiring
Corporation) beneficially owns, directly or indirectly, 40% or more of the then
outstanding shares of common stock of the Acquiring Corporation, or of the
combined voting power of the then-outstanding securities of such corporation
entitled to vote generally in the election of directors; or

        (d) approval by the stockholders of Thermo Electron of a complete
liquidation or dissolution of Thermo Electron.

10.     General Provisions

        10.1   Documentation of Awards

        Awards will be evidenced by written instruments, which may differ among
Participants, prescribed by the Board from time to time. Such instruments may be
in the form of agreements to be executed by both the Participant and the Company
or certificates, letters or similar instruments which need not be executed by
the participant but acceptance of which will evidence agreement to the terms
thereof. Such instruments shall conform to the requirements of the Plan and may
contain such other provisions (including provisions relating to events of
merger, consolidation, dissolution and liquidations, change of control and
restrictions affecting either the agreement or the Common Stock issued
thereunder), as the Board deems advisable.

        10.2   Rights as a Stockholder

        Except as specifically provided by the Plan or the instrument evidencing
the Award, the receipt of an Award will not give a Participant rights as a
Stockholder with respect to any shares covered by an Award until the date of
issue of a stock certificate to the participant for such shares.

        10.3   Conditions on Delivery of Stock

        The Company will not be obligated to deliver any shares of Common Stock
pursuant to the Plan or to remove any restriction from shares previously
delivered under the Plan (a) until all conditions of the Award have been
satisfied or removed, (b) until, in the opinion of the Company's counsel, all
applicable federal and state laws and regulations have been complied with, (c)
if the outstanding Common Stock is at the time listed on any stock exchange,
until the shares have been listed or authorized to be listed on such exchange
upon official notice of issuance, and (d) until all other legal matters in
connection with the issuance and delivery of such shares have been approved by
the Company's counsel. If the sale of Common Stock has not been registered under
the Securities Act of 1933, as amended, the Company may require, as a condition
to exercise of the Award, such representations or agreements as counsel for the
Company may consider appropriate to avoid violation of such act and may require
that the certificates evidencing such Common Stock bear an appropriate legend
restricting transfer.

        If an Award is exercised by the participant's legal representative, the
Company will be under no obligation to deliver Common Stock pursuant to such
exercise until the Company is satisfied as to the authority of such
representative.

        10.4   Tax Withholding

        The Company will withhold from any cash payment made pursuant to an
Award an amount sufficient to satisfy all federal, state and local withholding
tax requirements (the "withholding requirements").

        In the case of an Award pursuant to which Common Stock may be delivered,
the Board will have the right to require that the participant or other
appropriate person remit to the Company an amount sufficient to satisfy the
withholding requirements, or make other arrangements satisfactory to the Board
with regard to such requirements, prior to the delivery of any Common Stock. If
and to the extent that such withholding is required, the Board may permit the
participant or such other person to elect at such time and in such manner as the
Board provides to have the Company hold back from the shares to be delivered, or
to deliver to the Company, Common Stock having a value calculated to satisfy the
withholding requirement.

        10.5   Transferability of Awards

        Except as may be authorized by the Board, in its sole discretion, no
Award (other than an Award in the form of an outright transfer of cash or Common
Stock not subject to any restrictions) may be transferred other than by will or
the laws of descent and distribution, and during a Participant's lifetime an
Award requiring exercise may be exercised only by him or her (or in the event of
incapacity, the person or persons properly appointed to act on his or her
behalf). The Board may, in its discretion, determine the extent to which Awards
granted to a Participant shall be transferable, and such provisions permitting
or acknowledging transfer shall be set forth in the written agreement evidencing
the Award executed and delivered by or on behalf of the Company and the
Participant.

        10.6   Adjustments in the Event of Certain Transactions

        (a) In the event of a stock dividend, stock split or combination of
shares, or other distribution with respect to holders of Common Stock other than
normal cash dividends, the Board will make (i) appropriate adjustments to the
maximum number of shares that may be delivered under the Plan under Section 4
above, and (ii) appropriate adjustments to the number and kind of shares of
stock or securities subject to Awards then outstanding or subsequently granted,
any exercise prices relating to Awards and any other provisions of Awards
affected by such change.

        (b) In the event of any recapitalization, merger or consolidation
involving the Company, any transaction in which the Company becomes a subsidiary
of another entity, any sale or other disposition of all or a substantial portion
of the assets of the Company or any similar transaction, as determined by the
Board, the Board in its discretion may make appropriate adjustments to
outstanding Awards to avoid distortion in the operation of the Plan.

        10.7   Employment Rights

        Neither the adoption of the Plan nor the grant of Awards will confer
upon any person any right to continued employment with the Company or any
subsidiary or interfere in any way with the right of the Company or subsidiary
to terminate any employment relationship at any time or to increase or decrease
the compensation of such person. Except as specifically provided by the Board in
any particular case, the loss of existing or potential profit in Awards granted
under the Plan will not constitute an element of damages in the event of
termination of an employment relationship even if the termination is in
violation of an obligation of the Company to the employee.

        Whether an authorized leave of absence, or absence in military or
government service, shall constitute termination of employment shall be
determined by the Board at the time. For purposes of this Plan, transfer of
employment between the Company and its subsidiaries shall not be deemed
termination of employment.

        10.8   Other Employee Benefits

        The value of an Award granted to a Participant who is an employee, and
the amount of any compensation deemed to be received by an employee as a result
of any exercise or purchase of Common Stock pursuant to an Award or sale of
shares received under the Plan, will not constitute "earnings" or "compensation"
with respect to which any other employee benefits of such employee are
determined, including without limitation benefits under any pension, stock
ownership, stock purchase, life insurance, medical, health, disability or salary
continuation plan.

        10.9   Legal Holidays

        If any day on or before which action under the Plan must be taken falls
on a Saturday, Sunday or legal holiday, such action may be taken on the next
succeeding day not a Saturday, Sunday or legal holiday.

        10.10  Foreign Nationals

        Without amending the Plan, Awards may be granted to persons who are
foreign nationals or employed outside the United States or both, on such terms
and conditions different from those specified in the Plan, as may, in the
judgment of the Board, be necessary or desirable to further the purpose of the
Plan.

11.     Termination and Amendment

        The Plan shall remain in full force and effect until terminated by the
Board. Subject to the last sentence of this Section 11, the Board may at any
time or times amend the Plan or any outstanding Award for any purpose that may
at the time be permitted by law, or may at any time terminate the Plan as to any
further grants of Awards. No amendment of the Plan or any agreement evidencing
Awards under the Plan may adversely affect the rights of any participant under
any Award previously granted without such participant's consent.