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                                                                 Exhibit 10.5(b)

                              EMPLOYMENT AGREEMENT
                              --------------------

     This Agreement made as of the 10th day of November, 1999, between
PerkinElmer, Inc., a Massachusetts corporation (hereinafter called
the "Company"), and Angelo D. Castellana (hereinafter referred to as the
"Employee").


                                   WITNESSETH:
                                   -----------

     WHEREAS, the Employee is being employed in a management position with the
Company; and

     WHEREAS, the Employee hereby agrees to continue to perform such services
and duties of a management nature as shall be assigned to him; and

     WHEREAS, the Employee hereby agrees to the compensation herein provided and
agrees to serve the Company to the best of his ability during the period of this
Agreement.

     NOW, THEREFORE, in consideration of the sum of One Dollar, and of the
mutual covenants herein contained, the parties agree as follows:

1.   a)   Except as hereinafter otherwise provided, the Company agrees to employ
          the employee in a management position with the Company, and the
          Employee agrees to remain in the employment of the Company in that
          capacity for a period of one year from the date hereof and from year
          to year thereafter until such time as this Agreement is terminated.

     b)   The Company will, during each year of the term of this Agreement,
          place in nomination before the Board of Directors of the Company the
          name of the Employee for election as an Officer of the Company except
          when a notice of termination has been given in accordance with
          Paragraph 5(b).

2.   The Employee agrees that, during the specified period of employment, he
     shall, to the best of his ability, perform his duties, and shall devote his
     full business time, best efforts, business judgment, skill and knowledge to
     the advancement of the Company and its interests and to the discharge of
     his duties and responsibilities hereunder. The Employee shall not engage in
     any business, profession or occupation which would conflict with the
     rendition of the agreed-upon services, either directly or indirectly,
     without the prior approval of the Board of Directors, except for personal
     investment, charitable and philanthropic activities.



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3.   During the period of his employment under this Agreement, the Employee
     shall be compensated for his services as follows:

     a)   Except as otherwise provided in this Agreement, he shall be paid a
          salary during the period of this Agreement at a base rate to be
          determined by the Company on an annual basis. Except as provided in
          Subparagraph 3d, such annual base salary shall under no circumstances
          be fixed at a rate below the annual base rate then currently in
          effect;

     b)   He shall be reimbursed for any and all monies expended by him in
          connection with his employment for reasonable and necessary expenses
          on behalf of the Company in accordance with the policies of the
          Company then in effect;

     c)   He shall be eligible to participate under any and all bonus, benefit,
          pension, compensation, and option plans which are, in accordance with
          company policy, available to persons in his position (within the
          limitation as stipulated by such plans). Such eligibility shall not
          automatically entitle him to participate in any such plan;

     d)   If, because of adverse business conditions or for other reasons, the
          Company at any time puts into effect salary reductions applicable at a
          single rate to management employees of the Company generally, the
          salary payments required to be made under this Agreement to the
          Employee during any period in which such general reduction is in
          effect may be reduced by the same percentage as is applicable to all
          management employees of the Company generally. Any benefits made
          available to the Employee which are related to base salary shall also
          be reduced in accordance with any salary reduction.

4.

     a)   So long as the Employee is employed by the Company and for a period of
          one year after the termination of expiration of employment, the
          Employee will not directly or indirectly: (i) as an individual
          proprietor, partner, stockholder, officer, employee, director, joint
          venturer, investor, lender, or in any other capacity whatsoever (other
          than as the holder of not more than one percent (1%) of the total
          outstanding stock of a publicly held company), engage directly or
          indirectly in any business or entity, which competes with the business
          conducted by the Company or its affiliates in any city or geographic
          area in which the Company or its affiliates conduct material
          operations at the time of termination of employment under this
          Agreement, except as approved in advance by the Board after full and
          adequate disclosure; or (ii) recruit, solicit or induct, or attempt to
          induce, any


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                              Employment Agreement

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          employee or employees of the Company to terminate their employment
          with, to otherwise cease their relationship with, the Company; or
          (iii) solicit, divert or take away, or attempt to divert or to take
          away, the business or patronage of any of the clients, customers or
          accounts, of the Company that were contacted, solicited or served by
          the Employee while employed by the Company.

     b)   If any restriction set forth in this Section 4 is found by any court
          of competent jurisdiction to be unenforceable because it extends for
          too long a period of time or over too great a range of activities or
          in too broad a geographical areas it shall be interpreted to extend
          only over the maximum period of time, range of activities or
          geographic area as to which it may be enforceable.

     c)   The restrictions contained in this Section 4 are necessary for the
          protection of the business and goodwill of the Company and are
          considered by the Employee to be reasonable for such purpose. The
          Employee agrees that any breach of this Section 4 will cause the
          Company substantial and irrevocable damage and therefore, in the event
          of any such breach, in addition to such other remedies which may be
          available, the Company shall have the right to seek specific
          performance and injunctive relief.

     d)   The Employee agrees to sign and be bound by the Employee Patent and
          Proprietary Information Utilization Agreement in the form attached
          hereto.

     e)   During the period of his employment by the Company or for any period
          during which the Company shall continue to pay the Employee his salary
          under this Agreement, whichever shall be longer, the Employee shall
          not in any way whatsoever aid or assist any party seeking to cause,
          initiate or effect a Change in Control of the Company as defined in
          Paragraph 6 without the prior approval of the Board of Directors.

5.   Except for the Employee covenants set forth in Paragraph 4 which covenants
     shall remain in effect for the periods stated therein, and subject to
     Paragraph 6, this Agreement shall terminate upon the happening of any of
     the following events and (except as provided herein) all of the Company's
     obligations under this Agreement, including, but not limited to, making
     payments to the Employee shall cease and terminate:

     a)   On the effective date set forth in any resignation submitted by the
          Employee and accepted by the Company, or if no effective date is
          agreed upon, the date of receipt of such resignation letter;

     b)   One year after written notice of termination is given by the Company
          to the



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          Employee;

     c)   At the death of the Employee;

     d)   At the termination of the Employee for cause. As used in the
          Agreement, the term "cause" shall mean:

          i)   Misappropriating any funds or property of the Company;

          ii)  Unreasonable refusal to perform the duties assigned to him under
               this Agreement;

          iii) Conviction of a felony;

          iv)  Continuous conduct bringing notoriety to the Company and having
               an adverse effect on the name or public image of the Company;

          v)   Violation of the Employee's covenants as set forth in Paragraph 4
               above; or

          vi)  Continued failure by the Employee to observe any of the
               provisions of this Agreement after being informed of such breach.

     e)   Twelve months after written notice of termination (a "Disability
          Termination Notice") is given by the Company to the Employee based on
          a determination by the Board of Directors that the Employee is
          disabled (which, for purposes of this Agreement, shall mean that the
          Employee is unable to perform his regular duties, with such
          determination to be made by the Board of Directors, in reliance upon
          the opinion of the Employee's physician or upon the opinion of one or
          more physicians selected by the Company). A Disability Termination
          Notice shall be deemed properly delivered if given by the Company to
          the Employee on the 184th day of continuous disability of the
          Employee. Notwithstanding the foregoing, if, during the twelve-month
          period following proper delivery of a Disability Termination Notice as
          aforesaid, the Employee is no longer disabled and is able to return to
          work, such Disability Termination Notice shall be deemed automatically
          rescinded upon the Employee's return to work, and the employment of
          the Employee shall continue in accordance with the terms of this
          Agreement. During the first 184 days of continuous disability of the
          Employee, the Company will make periodic payments to the Employee in
          an amount equal to the difference between his base salary and the
          benefits received by the Employee under the Company's Short-Term
          Disability Income Plan. During the twelve-month period following
          proper delivery of a Disability Termination Notice as aforesaid, the
          Company will make periodic



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                              Employment Agreement


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          payments to the Employee in an amount equal to the difference between
          his base salary and the benefits provided by the Company's Long-Term
          Disability Plan. If any payments to the Employee under the Company's
          Long-Term Disability Plan are not subject to federal income taxes, the
          payments to be made directly by the Company pursuant to the preceding
          sentence shall be reduced such that the total amount received by the
          Employee (from the Company and from the Long-Term Disability Plan),
          after payment of any income taxes, is equal to the amount that the
          Employee would have received had he been paid his base salary, after
          payment of any income taxes on such base salary.

     f)   In the event of the termination of the Employee by the Company
          pursuant to paragraph 5(b) above, the Employee shall, for a period of
          one year from the date this agreement shall terminate, (i) continue to
          receive his Full Salary (as defined below), which shall be payable in
          accordance with the payment schedule in effect immediately prior to
          his employment termination, and (ii) continue to be entitled to
          participate in all employee benefit plans and arrangements of the
          Company (such as life, health and disability insurance and automobile
          arrangements) to the same extent (including coverage of dependents, if
          any) and upon the same terms as were in effect immediately prior to
          his termination. For purposes of this Agreement, "Full Salary" shall
          mean the Employee's annual base salary, plus the amount of any bonus
          or incentive payments received by the Employee with respect to the
          last full fiscal year of the Company for which all bonus or incentive
          payments to be made have been made.

     g)   In the event of a termination of employment pursuant to paragraph
          5(a), (c) or (d), the Company shall pay the Employee his full salary
          through the date of termination of employment.

6.   a)   In the event of a Change in Control of the Company (as defined below),
          the provisions of this Agreement shall be amended as follows:

          i)   Paragraph 1a shall be amended to read in its entirety as follows:

               "Except as hereinafter otherwise provided, the Company agrees to
               continue to employ the Employee in a management position with the
               Company, and the Employee agrees to remain in the employment in
               the Company in that capacity, for a period of three (3) years
               from the date of the Change in Control. Except as provided in
               Paragraph 3d, the Employee's salary as set forth in Paragraph 3a
               and his other employee benefits pursuant to the plans described
               in Paragraph 3c shall not be decreased during such period."




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                              Employment Agreement

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          ii)  Paragraph 5a shall be amended by the addition of the following
               provision at the end of such paragraph:

               "provided that the Employee agrees not to resign, except for Good
               Reason (as defined below), during the one-year period following
               the date of the Change in Control."

          iii) Paragraph 5b shall be deleted in its entirety.

          iv)  Paragraph 5f shall be amended to read in its entirety as follows:

               "Notwithstanding the foregoing provisions, if, within 36 months
               following the occurrence of a Change in Control, the Employee's
               employment by the Company is terminated (A) by the Company other
               than for Cause, which shall not include any failure to perform
               his dudes hereunder after giving notice or termination for Good
               Reason, disability or death or (B) by the Employee for Good
               Reason, (1) the Company shall pay to the Employee, on the date of
               his employment termination, a lump sum cash payment in an amount
               equal to the sum of (x) his unpaid base salary through the date
               of termination, (y) pro rata portion of prior year's bonus and
               (z) his Full Salary (as defined below) multiplied by three and
               (2) the Employee shall for 36 months following the occurrence of
               the Change in Control be eligible to participate in all employee
               benefit plans and arrangements of the Company (such as life,
               health and disability insurance and automobile arrangements but
               excluding incentive arrangements and grants of stock options) to
               the same extent (including coverage of dependents, if any) and
               upon the same terms as were in effect immediately prior to his
               termination. For purposes of this Agreement, "Full Salary" shall
               mean the Employee's annual base salary, plus the amount of any
               bonus or incentive payments received by the Employee with respect
               to the last full fiscal year of the Company for which all bonus
               or incentive payments to be made have been made. Payments under
               this Paragraph 5f shall be made without regard to whether the
               deductibility of such payments (or any other "parachute
               payments," as that term is defined in Section 280G of the
               Internal Revenue Code of 1986, as amended (the "Code"), to or for
               the benefit of the Employee) would be limited or precluded by
               Section 280G and without regard to whether such payments (or any
               other "parachute payments" as so defined in said Section 280G)
               would subject the Employee to the federal excise tax levied on
               certain "excess parachute payments" under Section 4999 of the
               Code (the "Excise Tax"). In addition, the Employee shall be
               entitled to receive a payment (the "Gross-Up Payment") which
               shall be an amount equal to the sum of (a) the Excise Tax imposed
               on any parachute payment, whether or not



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               payable under this Agreement, and (b) the amount necessary to pay
               all additional taxes imposed on (or economically borne by) the
               Employee (including the Excise Tax, state and federal income
               taxes and all applicable withholding taxes) attributable to the
               receipt of the Gross-Up Payment, computed assuming the
               application of the maximum tax rates provided by law. The
               determination of the Gross-Up Payment shall be made at the
               Company's expense by Arthur Andersen & Co. or by such other
               certified public accounting firm as the Board of Directors of the
               Company may designate prior to a Change in Control of the
               Company. In the event of any underpayment or overpayment under
               this Paragraph 5f as determined by Arthur Andersen & Co. (or such
               other firm as may have been designated in accordance with the
               preceding sentence), the amount of such underpayment or
               overpayment shall forthwith be paid to the Employee or refunded
               to the Company, as the case may be, with interest at the
               applicable federal rate provided for in Section 7872(f)(2) of the
               Code."

          v)   Paragraph 8 shall be amended to read in its entirety as follows:

               "The Employee may pursue any lawful remedy he deems necessary or
               appropriate for enforcing his rights under this Agreement
               following a Change in Control of the Company, and all costs
               incurred by the Employee in connection therewith (including
               without limitation attorneys' fees) shall be promptly reimbursed
               to him by the Company, regardless of the outcome of such
               endeavor."

     b)   For purposes of this Agreement, a "Change in Control of the Company"
          means an event or occurrence set forth in any one or more of clauses
          (i) through (iv) below (including an event or occurrence that
          constitutes a Change in Control under one or such clauses but is
          specifically exempted from another such clause):

                       (i) 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 or 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
          (1) the then-outstanding shares of common stock of the Company (the
          "Outstanding Company Common Stock") or (2) 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
          paragraph (i), the following acquisitions shall not constitute a
          Change in Control: (l) any acquisition directly from the Company



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          (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), (2) any acquisition by the Company, (3) any
          acquisition by any employee benefit plan (or related trust) sponsored
          or maintained by the Company or any corporation controlled by the
          Company, or (4) any acquisition by any corporation pursuant to a
          transaction which complies with subclauses (1) and (2) or clause (iii)
          of this Section 6b; or

                         (ii) 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 (1) who was a member of the Board on the date of the execution
          of this Agreement or (2) 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 (2) 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

                         (iii) 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: (1) 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


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          Business Combination, of the Outstanding Company Stock and Outstanding
          Company Voting Securities, respectively; and (2) 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

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

     c)   For purposes of this Agreement, "Good Reason" shall mean the
          occurrence of any of the following events: (i) a reduction in the
          Employee's base salary as in effect on the date hereof or as the same
          may be increased from time to time, except as provided in Paragraph
          3d; (ii) a failure by the Company to pay annual cash bonuses to the
          Employees in an amount at least equal to the most recent annual cash
          bonuses paid to the Employee; (iii) a failure by the Company to
          maintain in effect any material compensation or benefit plan in which
          the Employee participated immediately prior to the Change in Control,
          unless an equitable arrangement has been made with respect to such
          plan, or a failure to continue the Employee's participation therein on
          a basis not materially less favorable than existed immediately prior
          to the Change in Control; (iv) any significant and substantial
          diminution in the Employee's position, duties, authorities,
          responsibilities or title as in effect immediately prior to the Change
          in Control; (v) any requirement by the Company that the location at
          which the Employee performs his principal duties be changed to a new
          location outside a radius of 25 miles from the Employee's principal
          place of employment immediately prior to the Change in Control; (vi)
          any requirement by the Company that the Employee travel on an
          overnight basis to an extent not substantially consistent with the
          Employee's business travel obligations immediately prior to the Change
          in Control or (vii) the failure of the Company to obtain the
          agreement, in a form reasonably satisfactory to the Employee, from any
          successor to the Company to assume and agree to perform this
          Agreement. Notwithstanding the foregoing, the resignation shall not be
          considered to be for Good Reason if any such circumstances are fully
          corrected prior to the date of resignation. The Employee's right to
          terminate his employment for Good Reason shall not be affected by his
          incapacity due to physical or mental illness.

7.   Neither the Employee nor, in the event of his death, his legal
     representative, beneficiary or estate, shall have the power to transfer,
     assign, mortgage or otherwise encumber in advance



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     any of the payments provided for in this Agreement, nor shall any payments
     nor assets or funds of the Company be subject to seizure for the payment of
     any debts, judgments, liabilities, bankruptcy or other actions.

8.   Any controversy relating to this Agreement and not resolved by the Board of
     Directors and the Employee shall be settled by arbitration in the City of
     Boston, Commonwealth of Massachusetts, pursuant to the rules then obtaining
     of the American Arbitration Association, and judgment upon the award may be
     entered in any court having jurisdiction, and the Board of Directors and
     Employee agree to be bound by the arbitration decision on any such
     controversy. Unless otherwise agreed by the parties hereto, arbitration
     will be by three arbitrators selected from the panel of the American
     Arbitration Association. The full cost of any such arbitration shall be
     borne by the Company.

9.   Failure to insist upon strict compliance with any of the terms, covenants,
     or conditions hereof shall not be deemed a waiver of such term, covenant,
     or condition, nor shall any waiver or relinquishment of any right or power
     hereunder at any one or more times be deemed a waiver or relinquishment of
     such right or power at any other time or times by either party.

10.  All notices or other communications hereunder shall be in writing and shall
     be deemed to have been duly given when delivered personally to the Employee
     or to the General Counsel of the Company or when mailed by registered or
     certified mail to the other party (if to the Company, at 45 William Street,
     Wellesley, Massachusetts 02481, attention General Counsel; if to the
     Employee, at the last known address of the Employee as set forth in the
     records of the Company).

11.  This Agreement has been executed and delivered and shall be construed in
     accordance with the laws of the Commonwealth of Massachusetts. This
     Agreement is and shall be binding on the respective legal representatives
     or successors of the parties, but shall not be assignable except to a
     successor to the Company by virtue of a merger, consolidation or
     acquisition of all or substantially all of the assets of the Company. This
     Agreement constitutes and embodies the entire understanding and agreement
     of the parties and, except as otherwise provided herein, there are no
     other agreements or understandings, written or oral, in effect between the
     parties hereto relating to the employment of the Employee by the Company.
     All previous employment contracts between the Employee and the Company or
     any of the Company's present or former subsidiaries or affiliates is hereby
     canceled and of no effect.

12.  The Company shall require any successor (whether direct or indirect, by
     purchase, merger, consolidation or otherwise) to all or substantially all
     of the business or assets of the Company to assume expressly in writing and
     to agree to perform its obligations under this



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     Agreement in the same manner and to the same extent that the Company would
     be required to perform it if no such succession had taken place. Failure of
     the Company to obtain an assumption of this Agreement prior to the
     effectiveness of succession shall be a breach of this Agreement. As used in
     this Agreement, "the Company" shall mean the Company as defined above and
     any successor to its business or assets as aforesaid which assumes and
     agrees to perform this Agreement by operation of law, or otherwise.





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     IN WITNESS WHEREOF, the Company has caused its seal to be hereunto affixed
and these presents to be signed by its proper officers, and the Employee has
hereunto set his hand and seal the day and year first above written.


(SEAL)                                  PERKINELMER, INC.



                                        By: /s/ Gregory L. Summe
                                            -----------------------------------
                                            Gregory L. Summe
                                            Chairman and Chief Executive Officer



                                        Employee: /s/ Angelo D. Castellana
                                                  -----------------------------
                                                  Angelo D. Castellana




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