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                                                                Exhibit 10.18(a)

                  STOCK RESTRICTION AGREEMENT (OFFICER PROGRAM)

      AGREEMENT made this fifteenth day of July 2002, between PerkinElmer, Inc.,
a Massachusetts corporation (the "Company"), and Peter Coggins (the "Employee").

      For valuable consideration, receipt of which is acknowledged, the parties
hereto agree as follows:

1.    Grant of Shares. As of the date hereof, the Company shall issue to the
Employee, subject to the terms and conditions set forth in this Agreement and in
the PerkinElmer, Inc. 2001 Incentive Plan, 20,000 shares (the "Shares") of
common stock, $1.00 par value per share, of the Company ("Common Stock"). The
Company shall issue to the Employee one or more certificates in the name of the
Employee for that number of Shares granted to the Employee, subject to the
provisions of Section 19 of this Agreement. The Employee agrees that the Shares
shall be subject to the Purchase Option set forth in Section 2 of this Agreement
and the restrictions on transfer set forth in Section 4 of this Agreement. The
Employee may make an irrevocable election to exchange the Shares for an account
balance under the Company's Deferred Compensation Plan denominated in units
equal in value to the value of the Shares and distributable only in shares of
Common Stock at a time designated by the Employee at the time of such election;
such account balance shall be reduced to $.001 per share if the Employee ceases
to be employed by the Company for any reason or no reason, with or without
cause, before the date the Purchase Option expires. Such election shall be
effective only if it is made at least six months before the date the Purchase
Option expires.

2.    Purchase Option.

(a)         The Company shall have the right and option (the "Purchase Option")
to purchase from the Employee, for a sum of $.001 per share (the "Option
Price"), any part or all of the Shares if the Employee ceases to be employed by
the Company for any reason or no reason, with or without cause, before the date
the Purchase Option expires. The Purchase Option shall expire with respect to
all the shares on the earliest of the following dates or events:

      (1)   The last day of the Company's 2002 fiscal year if the Company's
earnings per share, determined as set forth in Exhibit A hereto, for that fiscal
year is at least 1.5 times the earnings per share for the Company's 2001 fiscal
year. For purposes of this paragraph (1) the earnings per share for the
Company's 2001 fiscal year, prior to adjustment, shall be $1.09.

      (2)   The last day of the Company's 2003 fiscal year if the earnings per
share, determined as set forth in Exhibit A hereto, for that fiscal year is at
least 1.5 times the earnings per share for the Company's 2001 fiscal year. For
purposes of this paragraph (2) the earnings per share for the Company's 2001
fiscal year, prior to adjustment, shall be $1.09.

      (3)   The last day of a three consecutive fiscal year period of the
Company beginning after the 2001 fiscal year in which the earnings per share for
each fiscal year in such period, determined as set forth in Exhibit A hereto, is
at least 1.15 times the earnings per share for

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the preceding fiscal year of the Company.

      (4)   The date the Employee dies or becomes permanently disabled. The
Employee shall be deemed to be permanently disabled if he has been unable to
perform his duties for the Company for a six consecutive month period. The
determination of disability shall be made by the Board of Directors of the
Company, in reliance upon the opinion of the Employee's physician or upon the
opinion of one or more physicians selected by the Company.

      (5)   Notwithstanding the provisions of the Plan to the contrary, the
occurrence of a Change in Control of the Company. For purposes of this
Agreement, a "Change in Control" means an event or occurrence set forth in any
one or more of paragraphs (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 Securities Exchange
Act of 1934, as amended (the "Exchange Act")) (a "Person") of beneficial
ownership of any capital stock of the Company if, after such acquisition, such
Person beneficially owns (within the meaning of Rule 13d-3 promulgated under the
Exchange Act) 20% or more of either (i) the then-outstanding shares of common
stock of the Company (the "Outstanding Company Common Stock") or (ii) the
combined voting power of the then-outstanding securities of the Company entitled
to vote generally in the election of directors (the "Outstanding Company Voting
Securities"); provided, however, that for purposes of this subsection (a), the
following acquisitions shall not constitute a Change in Control: (i) any
acquisition directly from the Company (excluding an acquisition pursuant to the
exercise, conversion or exchange of any security exercisable for, convertible
into or exchangeable for common stock or voting securities of the Company,
unless the Person exercising, converting or exchanging such security acquired
such security directly from the Company or an underwriter or agent of the
Company), (ii) any acquisition by the Company, (iii) any acquisition by any
employee benefit plan (or related trust) sponsored or maintained by the Company
or any corporation controlled by the Company, or (iv) any acquisition by any
corporation pursuant to a transaction which complies with clauses (i) and (ii)
of paragraph (C) of this Section 2(a)(5); or

                  (B)   such time as the Continuing Directors (as defined below)
do not constitute a majority of the Board (or, if applicable, the Board of
Directors of a successor corporation to the Company), where the term "Continuing
Director" means at any date a member of the Board (i) who was a member of the
Board on the date of the execution of this Agreement 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 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 Board; or

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                  (C)   the consummation of a merger, consolidation,
reorganization, recapitalization or statutory share exchange involving the
Company or a sale or other disposition of all or substantially all of the assets
of the Company (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 Company Common Stock and Outstanding Company Voting
Securities immediately prior to such Business Combination beneficially own,
directly or indirectly, more than 50%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 the
Company or substantially all of the Company'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 Company Common Stock and Outstanding Company Voting Securities,
respectively; and (ii) no Person (excluding the Acquiring Corporation or any
employee benefit plan (or related trust) maintained or sponsored by the Company
or by the Acquiring Corporation) beneficially owns, directly or indirectly, 20%
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
(except to the extent that such ownership existed prior to the Business
Combination); or

                  (D)   approval by the stockholders of the Company of a
complete liquidation or dissolution of the Company.

      (6)   July 14, 2009.

(b)         The EPS which is required to be achieved to cause the expiration of
the Purchase Option pursuant to Section 2(a)(1), (2), or (3) ("Target EPS") and
the EPS for the Company's 2001 fiscal year shall be subject to adjustment in
accordance with Exhibit A. The determination of EPS for a fiscal year of the
Company and any adjustments thereto pursuant to Exhibit A shall be proposed by
the Company's management and verified by the Company's independent public
accountants.

(c)         For purposes of this Agreement, employment with the Company shall
include employment with a parent or subsidiary of the Company.

3.    Exercise of Purchase Option and Closing.


(a)         If the Employee ceases to be employed by the Company before the
expiration of the Purchase Option, the Company may exercise the Purchase Option
by delivering or mailing to the Employee (or his estate), in accordance with
Section 14, within 60 days after the termination of the employment of the
Employee with the Company, a written notice of exercise of the Purchase Option.
Such notice shall specify the number of Shares to be purchased. If and to the

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extent the Purchase Option is not so exercised by the giving of such a notice
within such 60-day period, the Purchase Option shall automatically expire and
terminate effective upon the expiration of such 60-day period.

(b)         Within 10 days after his receipt of the Company's notice of the
exercise of the Purchase Option pursuant to subsection (a) above, the Employee
(or his estate) shall tender to the Company at its principal offices the
certificate or certificates representing the Shares which the Company has
elected to purchase, duly endorsed in blank by the Employee or with duly
endorsed stock powers attached thereto, all in form suitable for the transfer of
such Shares to the Company. Promptly following its receipt of such certificate
or certificates, the Company shall deliver or mail to the Employee a check in
the amount of the aggregate Option Price therefor.

(c)         After the time at which any Shares are required to be delivered to
the Company for transfer to the Company pursuant to subsection (b) above, the
Company shall not pay any dividend to the Employee on account of such Shares or
permit the Employee to exercise any of the privileges or rights of a stockholder
with respect to such Shares, but shall, in so far as permitted by law, treat the
Company as the owner of such Shares.

4.    Restrictions on Transfer.


(a)         Except as otherwise provided in subsection (b) below, the Employee
shall not, during the term of the Purchase Option, sell, assign, transfer,
pledge, hypothecate or otherwise dispose of, by operation of law or otherwise
(collectively "transfer"), any of the Shares, or any interest therein, unless
and until such Shares are no longer subject to the Purchase Option.

(b)         Notwithstanding the foregoing, the Employee may transfer Shares to
or for the benefit of any spouse, child or grandchild, or to a trust for their
benefit, provided that such Shares shall remain subject to this Agreement
(including without limitation the restrictions on transfer set forth in this
Section 4 and the Purchase Option) and such permitted transferee shall, as a
condition to such transfer, deliver to the Company a written instrument
confirming that such transferee shall be bound by all of the terms and
conditions of this Agreement.

5.    Effect of Prohibited Transfer. The Company shall not be required (a) to
transfer on its books any of the Shares which shall have been sold or
transferred in violation of any of the provisions set forth in this Agreement,
or (b) to treat as owner of such Shares or to pay dividends to any transferee to
whom any such Shares shall have been so sold or transferred in violation of any
of the provisions in this Agreement.

6.    Restrictive Legend. Prior to the expiration of the Purchase Option, all
certificates representing Shares shall have affixed thereto a legend in
substantially the following form, in addition to any other legends that may be
required under federal or state securities laws:

      "The shares of stock represented by this certificate are subject to
      restrictions on transfer and an option to purchase set forth in a certain
      Stock Restriction Agreement between the corporation and the registered
      owner of these shares (or his predecessor in interest), and

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      such Agreement is available for inspection without charge at the office of
      the Secretary of the corporation."

7.    Provisions of Plan. This Agreement is subject to the provisions of the
      Plan, a copy of which is furnished to the Employee with this Agreement.

8.    Adjustments for Stock Splits, Stock Dividends, etc.

(a)         If from time to time during the term of the Purchase Option there is
any stock split-up, reverse stock split, stock dividend, stock distribution,
recapitalization, combination of shares, reclassification of shares, spin-off or
other similar change in capitalization event or other reclassification of the
Common Stock of the Company, or any distribution to holders of Common Stock
other than a normal cash dividend, any and all new, substituted or additional
securities to which the Employee is entitled by reason of his ownership of the
Shares shall be immediately subject to the Purchase Option, the restrictions on
transfer and other provisions of this Agreement in the same manner and to the
same extent as the Shares, and the Option Price shall be appropriately adjusted.

(b)         If the Shares are converted into or exchanged for, or stockholders
of the Company receive by reason of any distribution in total or partial
liquidation, securities of another corporation, or other property (including
cash), pursuant to any merger of the Company or acquisition of its assets, other
than one that constitutes a Change in Control for the purpose of Section 2, then
the rights of the Company under this Agreement shall inure to the benefit of the
Company's successor and this Agreement shall apply to the securities or other
property received upon such conversion, exchange or distribution in the same
manner and to the same extent as to the Shares.

9.    Withholding Taxes.

(a)         The Employee acknowledges and agrees that the Company has the right
to deduct from payments of any kind otherwise due to the Employee any federal,
state or local taxes of any kind required by law to be withheld with respect to
the transfer for tax purposes of the Shares as well as with respect to any
dividend income derived from the Shares prior to such transfer, or the lapse of
the purchase option.

(b)         If the Employee elects, in accordance with Section 83(b) of the
Internal Revenue Code of 1986, as amended, to recognize ordinary income in the
year of transfer of the Shares, the Company will require at the time of such
election a payment for withholding tax purposes based on the fair market value
of such Shares as of the day of transfer to the Employee.

(c)         The Employee may, to the extent then permitted under applicable law,
satisfy any such tax withholding obligations in whole or in part by delivery to
the Company of shares of Common Stock, including the Shares, valued for such
purposes at their fair market value at the time such tax withholding obligation
arises, as determined in good faith by the Company (which determination shall be
based on the trading value of the Common Stock if the Common Stock is listed on
a national securities exchange at the time of such determination).

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10.   Severability. The invalidity or unenforceability of any provision of this
Agreement shall not affect the validity or enforceability of any other provision
of this Agreement, and each other provision of this Agreement shall be severable
and enforceable to the extent permitted by law.

11.   Waiver. Any provision contained in this Agreement may be waived, either
generally or in any particular instance, by the Board of Directors of the
Company.

12.   Binding Effect. This Agreement shall be binding upon and inure to the
benefit of the Company and the Employee and their respective heirs, executors,
administrators, legal representatives, successors and assigns, subject to the
restrictions on transfer set forth in Section 4 of this Agreement.

13.   No Rights To Employment. Nothing contained in this Agreement shall be
construed as giving the Employee any right to be retained, in any position, as
an employee of the Company.

14.   Notice. All notices required or permitted hereunder shall be in writing
and deemed effectively given upon personal delivery or upon deposit in the
United States Post Office, by registered or certified mail, postage prepaid,
addressed to the other party hereto at the address shown beneath his or its
respective signature to this Agreement, or at such other address or addresses as
either party shall designate to the other in accordance with this Section 14.

15.   Pronouns. Whenever the context may require, any pronouns used in this
Agreement shall include the corresponding masculine, feminine or neuter forms,
and the singular form of nouns and pronouns shall include the plural, and
vice-versa.

16.   Entire Agreement. This Agreement constitutes the entire agreement between
the parties, and supersedes all prior agreements and understandings, relating to
the subject matter of this Agreement.

17.   Amendment. This Agreement may be amended or modified only by a written
instrument executed by both the Company and the Employee.

18.   Governing Law. This Agreement shall be construed, interpreted and enforced
in accordance with the laws of the Commonwealth of Massachusetts.

19.   Delivery of Certificates. The Employee authorizes the Company, on his
behalf, to hold the Shares on book entry until the date on which the Shares are
no longer subject to the Purchase Option.

              [The balance of the page is intentionally left blank]

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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year first above written.

                                         PerkinElmer, Inc.

                                         /s/ Richard Walsh

                                         By:  Senior Vice President
                                            45 William Street
                                            Wellesley, Massachusetts 02481


                                         Peter Coggins

                                         /s/ Peter Coggins


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                                    EXHIBIT A

                        DEFINITION OF EARNINGS PER SHARE

      (a)   Earnings Per Share shall mean post-tax earnings per common share for
the applicable fiscal year determined on a fully diluted basis as reported in
the Company's annual consolidated financial statements, adjusted as hereinafter
described.


      (b)   If any of the following events occurs after the end of the Company's
2001 fiscal year, then in each fiscal year in which any such event directly
affects post-tax earnings per share, including the 2001 fiscal year, a
corresponding adjustment shall be made to arrive at earnings per share for such
year:

            (1)   Any common stock split or common stock dividend, common stock
                  subdivision or reclassification.


            (2)   Any change in accounting principles or Company accounting
                  practices.


            (3)   Any change in laws, regulations or interpretations thereof.


            (4)   Any items of a non-recurring nature, as evidenced by their
                  exclusion from adjusted earnings in the Company's reported
                  quarterly financial statements.


            (5)   Any extraordinary item, determined under generally accepted
                  accounting principles.


      (c)   In the event a significant business is sold, earnings per share and
Target EPS (as defined in Section 2(b)) shall be appropriately adjusted by the
earnings per share of the divested business and shall be appropriately adjusted
by the interest from the proceeds of the sale. In the event a significant
business is acquired, Target EPS shall be appropriately adjusted in accordance
with the acquisition plan approved by the Company's Board of Directors and
earnings per share shall be appropriately adjusted by the actual results of the
acquired operations.

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