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                                                                     Exhibit 8.2

                           [BROWN RUDNICK LETTERHEAD]

                                                 As of November __, 1999


Vivid Technologies, Inc.
10E Commerce Way
Woburn, MA 01801

         RE:  ACQUISITION OF VIVID TECHNOLOGIES, INC. BY PERKINELMER, INC.

Ladies and Gentlemen:

         This opinion is being delivered to you in connection with the filing of
a registration statement (the "Registration Statement") on Form S-4, which
includes the Proxy Statement/Prospectus relating to the Agreement and Plan of
Merger dated as of October 4, 1999, by and among PerkinElmer, Inc. ("Parent"), a
Massachusetts corporation , Venice Acquisition Corp. ("Subsidiary"), a Delaware
corporation and wholly-owned subsidiary of Parent, and Vivid Technologies, Inc.,
a Delaware corporation ("Company") relating to the acquisition of all of the
issued and outstanding stock of Company ("the Merger Plan"). Except as otherwise
provided, capitalized terms not defined herein have the meanings ascribed to
them in the Merger Plan and the exhibits thereto or in the letters delivered to
Brown, Rudnick, Freed & Gesmer by Parent and the Company containing certain
facts and representations of Parent and Company relevant to this opinion (the
"Representation Letters").

         In rendering this opinion, we have reviewed and relied upon the Merger
Plan, the Registration Statement and the exhibits thereto, the Representation
Letters and such other documents as we have deemed necessary in rendering this
opinion. We have assumed the authenticity of original documents, the accuracy of
copies, that any party executing any document upon which we have relied has the
legal capacity to sign such document and that all signatures on such documents
are genuine.

         We have assumed that all parties to the Merger Plan and to any other
documents examined by us have acted, and will act, in accordance with the terms
of such Merger Plan and documents and that the Merger will be completed at the
Effective Time pursuant to the terms and conditions set forth in the Merger Plan
without the waiver or modification of any such terms and conditions.
Furthermore, we have assumed that all representations contained in the Merger
Plan, as well as those representations contained in the Representation Letters,
are, and at the Effective Time will be, true and complete in all material
respects, and that any representation made in any of the documents referred to
herein "to the best of the knowledge and belief" (or similar qualification) of
any person or party is correct without such


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Vivid Technologies, Inc.
As of November __, 1999
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qualification. Should there be any material inaccuracy in the representation
contained in the Merger Plan or in Representation Letters, the tax consequences
of the proposed transaction could be substantially and adversely different from
those set forth in this opinion letter. We have also assumed that as to all
matters for which a person or entity has represented that such person or entity
is not a party to, does not have, or is not aware of, any plan, intention,
understanding, or agreement, there is no such plan, intention, understanding, or
agreement. We have not attempted to verify independently such representations,
but in the course of our representation, nothing has come to our attention that
would cause us to question the accuracy thereof.

                                      FACTS

         Pursuant to the Merger Plan between Parent, Company and Subsidiary,
Subsidiary will merge into the Company under the applicable provisions of
Delaware law (the "Merger"), with the Company surviving the Merger. As a result
of the Merger, Company will become a wholly-owned subsidiary of Parent. Company
will assume no Subsidiary liabilities pursuant to the Merger Plan. No Subsidiary
stock will be used as consideration in the Merger. Each issued and outstanding
share of Company common stock ("Common Stock") issued and outstanding at the
Effective Time (as defined in the Merger Plan) of the Merger, will be converted
into the right to receive a number of shares of PerkinElmer common stock equal
to the Exchange Ratio (as defined in the Merger Plan) ("Parent Common Stock").
Parent will not issue fractional shares of its Common Stock; instead, each
Company stockholder who would otherwise be entitled to a fractional share of
Parent Common Stock will receive cash equal to the Market Value (as defined in
the Merger Plan) of such fractional share. No cash or other property will be
paid to any Company stockholder in respect of such stockholder's Capital Stock,
other than cash paid in lieu of fractional shares of Parent Common Stock.

         Based solely on the facts and representations and assumptions described
above, it is our opinion that:

         The Merger will be treated as a reorganization within the meaning of
         Section 368(a) of the Internal Revenue Code of 1986, as amended.

         While our opinions and views expressed herein are based upon our best
interpretations of existing sources of law and express what we believe a court
would conclude if presented with these issues, no assurance can be given that
such interpretations would be followed if they became the subject of judicial or
administrative proceedings. Furthermore, our opinions are based on existing law.
No assurance can be given that legislative or administrative changes, or court
decisions, which may or may not be retroactive with respect to transactions


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Vivid Technologies, Inc.
As of November __, 1999
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completed prior to the effective dates of such changes, will not significantly
affect the tax consequences to the parties. We assume no obligation to inform
you of such changes. Although we believe that all of the factual assumptions and
representations upon which we have relied are warranted, we can give no
assurance that the Internal Revenue Service would agree.

         We express no opinion as to the tax treatment of any of the
transactions described above that are not specifically addressed in the
foregoing opinion. In particular, we express no opinion regarding any other
federal, state, local or foreign income, estate, gift, transfer, sales, use or
any other tax consequence of the Merger.

         In rendering this opinion, we have assumed that Hale & Dorr LLP has
delivered, and has not withdrawn, an opinion that is substantially similar to
this one.

         This opinion is intended solely for the purpose of inclusion as an
exhibit to the Registration Statement. It may not be relied upon by any other
person or entity, and may not be made available to any other person or entity,
without our prior written consent. We hereby consent to the filing of this
opinion as an exhibit to the Registration Statement and further consent to the
use of our name in connection with the references to this opinion and the tax
consequences of the Merger. In giving this consent, however, we do not admit
that we are in the category of persons whose consent is required under Section 7
of the Securities Act of 1933, as amended.

                                           Very truly yours,



                                           BROWN, RUDNICK, FREED & GESMER



                                           ____________________________________
                                           BROWN, RUDNICK, FREED & GESMER, P.C.
                                           a partner