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                                                                Exhibit 12(a)(6)


This announcement is neither an offer to purchase nor a solicitation of an offer
to sell Shares. The Offer is being made solely by the Offer to Purchase and the
related Letter of Transmittal and is being made to all holders of Shares. The
Offer is not being made to (nor will tenders be accepted from or on behalf of)
holders of Shares in any jurisdiction in which the making of the Offer or the
acceptance thereof would not be in compliance with the laws of such
jurisdiction. In any jurisdiction where the securities, blue sky or other laws
require the Offer to be made by a licensed broker or dealer, the Offer shall be
deemed to be made on behalf of the Purchaser by J.P. Morgan Securities Inc. or
one or more registered brokers or dealers licensed under the laws of such
jurisdiction.

NOTICE OF OFFER TO PURCHASE FOR CASH
ALL OUTSTANDING SHARES OF COMMON STOCK OF

TREX MEDICAL CORPORATION

AT

$2.15 NET PER SHARE

BY

TREX MEDICAL ACQUISITION, INC.

A WHOLLY-OWNED SUBSIDIARY OF
THERMO ELECTRON CORPORATION

Trex Medical Acquisition, Inc. (the "Purchaser"), a Delaware corporation and a
wholly-owned subsidiary of Thermo Electron Corporation, a Delaware corporation
("Thermo Electron"), is offering to purchase all outstanding shares of common
stock, par value $0.01 per share (the "Shares"), of Trex Medical Corporation, a
Delaware corporation (the "Company"), at a purchase price of $2.15 per Share,
net to the seller in cash, without interest thereon, upon the terms and subject
to the conditions set forth in the Offer to Purchase dated October 25, 2000 (the
"Offer to Purchase") and in the related Letter of Transmittal (which, together
with any amendments or supplements thereto, collectively constitute the
"Offer").

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  THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY
      TIME, ON WEDNESDAY, NOVEMBER 22, 2000, UNLESS THE OFFER IS EXTENDED.

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THE OFFER IS CONDITIONED UPON, AMONG OTHER THINGS, THERE BEING VALIDLY TENDERED
AND NOT WITHDRAWN PRIOR TO THE EXPIRATION OF THE OFFER THAT NUMBER OF SHARES
WHICH, TOGETHER WITH SHARES OWNED BY THERMO ELECTRON AND TREX MEDICAL
ACQUISITION, INC., CONSTITUTES AT LEAST NINETY PERCENT (90%) OF THE OUTSTANDING
SHARES OF THE COMPANY ON THE EXPIRATION DATE. THE OFFER IS ALSO SUBJECT TO
CERTAIN OTHER IMPORTANT TERMS AND CONDITIONS CONTAINED IN THE OFFER TO PURCHASE.

The Offer is the first step in Thermo Electron's plan to take the Company
private. The purpose of the Offer is to acquire the minority interest in the
Company as part of an overall reorganization of Thermo Electron and the sale of
all of the Company's operating assets. If the Offer is completed, Thermo
Electron and the Purchaser together will own at least 90% of the Shares.
Promptly following the closing of the Offer, Thermo Electron plans to contribute
its Shares to the Purchaser and cause the Purchaser to merge with and into the
Company in a so-called "short-form" merger between the Company and the Purchaser
(the "Merger"). Stockholders of the Company who do not tender their Shares in
the Offer will not be entitled to vote on the Merger. The consideration per
Share in the Merger (other than with respect to Shares

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held by stockholders, if any, who are entitled to and perfect their appraisal
rights under Delaware law) would be the same as the Offer price of $2.15.

For purposes of the Offer, the Purchaser will be deemed to have accepted for
payment, and thereby purchased, Shares validly tendered and not properly
withdrawn if, as and when the Purchaser gives oral or written notice to American
Stock Transfer & Trust Company (the "Depositary") of the Purchaser's acceptance
for payment of such Shares pursuant to the Offer. Upon the terms and subject to
the conditions of the Offer, payment for Shares so accepted for payment pursuant
to the Offer will be made by deposit of the aggregate purchase price therefor
with the Depositary, which will act as agent for tendering stockholders for the
purpose of receiving payment from the Purchaser and transmitting such payment to
stockholders whose Shares have been accepted for payment. UNDER NO CIRCUMSTANCES
WILL INTEREST ON THE PURCHASE PRICE FOR SHARES BE PAID, REGARDLESS OF ANY
EXTENSION OF THE OFFER OR ANY DELAY IN MAKING SUCH PAYMENT. In all cases,
payment for Shares tendered and accepted for payment pursuant to the Offer will
be made only after timely receipt by the Depositary of (i) certificates
evidencing Shares ("Share Certificates") or timely confirmation of a book-entry
transfer of such Shares into the Depositary's account at the Book-Entry Transfer
Facility (as defined in the section of the Offer to Purchase captioned "The
Tender Offer -- Acceptance For Payment And Payment For Shares") pursuant to the
procedures set forth in the section of the Offer to Purchase captioned "The
Tender Offer - Procedures For Accepting The Offer And Tendering Shares," (ii)
the Letter of Transmittal (or a facsimile thereof), properly completed and duly
executed, with any required signature guarantees, or an Agent's Message (as
defined in the section of the Offer to Purchase captioned "The Tender Offer --
Acceptance For Payment And Payment For Shares") in connection with a book-entry
transfer and (iii) any other documents required by the Letter of Transmittal.

The term "Expiration Date" means 12:00 midnight, New York City time, on
Wednesday, November 22, 2000, unless and until the Purchaser, in its sole
discretion, shall have extended the period during which the Offer is open, in
which event the term "Expiration Date" shall mean the latest time and date at
which the Offer, as so extended by the Purchaser, shall expire.

Subject to the applicable rules and regulations of the Securities and Exchange
Commission, the Purchaser expressly reserves the right, in its sole discretion,
at any time and from time to time, to extend the period during which the Offer
is open for any reason, including the failure to satisfy any of the conditions
specified in the section of the Offer to Purchase captioned "The Tender Offer --
Certain Conditions Of The Offer," and thereby delay acceptance for payment of,
or payment for, any Shares, by giving oral or written notice of such extension
to the Depositary. Any such extension will be followed as promptly as
practicable by a public announcement thereof, such announcement to be made no
later than 9:00 a.m., New York City time, on the next business day after the
previously scheduled Expiration Date. During any such extension, all Shares
previously tendered and not properly withdrawn will remain subject to the Offer,
subject to the right of a tendering stockholder to withdraw such stockholder's
Shares.

Except as otherwise provided in the section of the Offer to Purchase captioned
"The Tender Offer -- Withdrawal Rights," tenders of Shares made pursuant to the
Offer are irrevocable. Shares tendered pursuant to the Offer may be withdrawn at
any time prior to the Expiration Date and, unless previously accepted for
payment by the Purchaser pursuant to the Offer, may also be withdrawn at any
time after December 22, 2000. In order for a withdrawal to be effective, a
written, telegraphic or facsimile transmission notice of withdrawal must be
timely received by the Depositary at one of its addresses set forth on the back
cover of the Offer to Purchase. Any such notice of withdrawal must specify the
name of the person who tendered the Shares to be withdrawn, the number of Shares
to be withdrawn and the name of the registered holder of the Shares to be
withdrawn, if different from that of the person who tendered such Shares. If
Share Certificates to be withdrawn have been delivered or otherwise identified
to the Depositary, then, prior to the physical release of such Share
Certificates, the tendering stockholder must also submit the serial numbers
shown on such Share Certificates to the Depositary, and the signatures on the
notice of withdrawal must be guaranteed by an Eligible Institution (as defined
in the section of the Offer to Purchase captioned "The Tender Offer --
Procedures For Accepting The Offer And Tendering Shares"), unless such Shares
have been tendered for the account of an Eligible Institution. If Shares have
been tendered pursuant to the procedures for book-entry transfer, as set forth
in the section of the Offer to Purchase captioned "The Tender Offer --
Procedures For Accepting The Offer And Tendering Shares," any notice of
withdrawal must specify the name and number of the account at the Book-Entry
Transfer Facility to be credited with the withdrawn Shares and must otherwise
comply with the procedures of the Book-Entry Transfer Facility. Withdrawals may
not be revoked, and any Shares properly withdrawn will thereafter be deemed not
to have been validly tendered for purposes of the Offer. However, withdrawn
Shares may be retendered at any time prior to the Expiration Date by following
the procedures described in the section of the Offer to Purchase captioned "The
Tender Offer -- Procedures For Accepting The Offer And Tendering Shares." All
questions as to the form and validity (including the time of

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receipt) of any notice of withdrawal will be determined by the Purchaser, in its
sole discretion, whose determination will be final and binding.

The information required to be disclosed by Rule 14d-6(d) and Rule 13e-3(e)(1)
of the General Rules and Regulations under the Securities Exchange Act of 1934,
as amended, is contained in the Offer to Purchase and is incorporated herein by
reference.

The Company has provided the Purchaser with the Company's stockholder list and
security position listings for the purpose of disseminating the Offer to holders
of Shares. The Offer to Purchase, the related Letter of Transmittal and, if
required, other relevant material will be mailed to record holders of Shares
whose names appear on the Company's stockholder list and will be furnished to
brokers, dealers, commercial banks, trust companies and similar persons whose
names, or the names of whose nominees, appear on the Company's stockholders list
or, if applicable, who are listed as participants in a clearing agency's
security position listing for subsequent transmittal to beneficial owners of
Shares.

The receipt of cash for Shares pursuant to the Offer generally will be treated
as a taxable transaction for U.S. federal income tax purposes.

THE OFFER TO PURCHASE AND THE RELATED LETTER OF TRANSMITTAL CONTAIN IMPORTANT
INFORMATION THAT SHOULD BE READ CAREFULLY BEFORE ANY DECISION IS MADE WITH
RESPECT TO THE OFFER.

Tendering stockholders of record who tender Shares directly will not be
obligated to pay brokerage fees or commissions or, except as set forth in
Instruction 6 of the Letter of Transmittal, stock transfer taxes on the purchase
of Shares by the Purchaser pursuant to the Offer. Stockholders who hold their
Shares through a bank or a broker should check with such institution as to
whether it charges any service fees. The Purchaser will pay the expenses of the
Depositary, D.F. King & Co., Inc., which is acting as the information agent (the
"Information Agent"), and J.P. Morgan Securities Inc., which is acting as dealer
manager (the "Dealer Manager"), in connection with the Offer.

Questions and requests for assistance or for additional copies of the Offer to
Purchase, the Letter of Transmittal and all other materials in connection with
the Offer may be directed to the Information Agent or the Dealer Manager as set
forth below, and copies will be furnished promptly at the Purchaser's expense.
No fees or commissions will be paid to brokers, dealers or any other persons
(other than the Dealer Manager and the Information Agent) for soliciting tenders
of Shares pursuant to the Offer.

The Information Agent for the Offer is:
D.F. KING & CO., INC.
77 Water Street, 20th Floor
New York, NY 10005
Bankers and Brokers Call Collect: (212) 425-1685
All Others Call Toll Free: (800) 549-6697


The Dealer Manager for the Offer is:
J.P. MORGAN SECURITIES INC.
60 Wall Street
New York, NY 10260
(212) 648-6771


October 25, 2000