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                                                                     EXHIBIT 2.2

                                                                  EXECUTION COPY


                         REGISTRATION RIGHTS AGREEMENT


         THIS REGISTRATION RIGHTS AGREEMENT (this "Agreement") is entered into
as of December 29, 1995, by and between PACIFIC SCIENTIFIC COMPANY, a
California corporation ("PSC"), and each of the Persons who have executed this
Agreement and are named in Annex A to this Agreement (each sometimes referred
to herein individually as an "Investor" and sometimes collectively as the
"Investors").

                                    RECITALS

         A.      Investors collectively own outstanding shares of common stock
of Met One, Inc., a California corporation ("M1").

         B.      Concurrently herewith, M1 Acquisition Corp., a California
corporation and wholly-owned subsidiary of PSC ("Acquisition") merged with and
into M1 (the "Merger") in accordance with the terms and conditions set forth in
that certain Agreement and Plan of Merger (the "Merger Agreement").

         C.      In connection with the Merger, Investors will receive shares
of newly issued common stock of PSC (the "Investor Shares") in exchange for all
of their stock in M1.

         D.      Also in connection with the Closing under the Merger
Agreement, Louis J. Petralli, one of the Investors, sold to M1 certain real
property and buildings pursuant to a Purchase and Sale Agreement and Joint
Escrow Instructions.  In exchange for such real property and buildings,
additional shares of PSC common stock are to be issued to Mr. Petralli (the
"Petralli Shares").  The Investor Shares and the Petralli Shares are referred
to herein collectively as the "Shares."

         E.      The execution and delivery of this Agreement by the parties
hereto are a condition to consummation of the transactions contemplated in the
Merger Agreement.  PSC agrees to enter into this Agreement in exchange for the
agreements, covenants and promises made by the Investors as parties to the
Merger Agreement.

         Therefore, the parties hereto hereby agree as follows:

         1.      Definitions.  Unless the context otherwise requires, the terms
defined in this Section 1 shall have the
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meanings herein specified for all purposes of this Agreement, applicable to
both the singular and plural forms of any of the terms herein defined.

         "Agreement" means this Registration Rights Agreement.

         "Board" means the Board of Directors of PSC.

         "Closing Date" means the Closing Date as such term is defined in the
Merger Agreement.

         "Common Stock" means the common stock of PSC.

         "Commission" means the Securities and Exchange Commission.

         "Exchange Act" means the Securities Exchange Act of 1934, as amended.

         "Investor" has the meaning assigned to it in the introductory
paragraph of this Agreement.

         "Person" includes any natural person, corporation, trust, association,
company, partnership, joint venture and other entity and any government,
governmental agency, instrumentality or political subdivision.

         "Prospectus" means the prospectus included in any Registration
Statement (including, without limitation, a prospectus that discloses
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule 430A under the Securities Act), as
amended or supplemented by any prospectus supplement, with respect to the terms
of the offering of any portion of the Registrable Securities covered by such
Registration Statement and all other amendments and supplements to the
prospectus, including post-effective amendments, and all material incorporated
by reference or deemed to be incorporated by reference in such prospectus.

         The terms "register," "registered" and "registration" refer to a
registration effected by preparing and filing a registration statement in
compliance with the Securities Act, and the declaration or ordering of the
effectiveness of such registration statement.

         "Registration Expenses" means all reasonable expenses incurred by PSC
in complying with Section 2 and Section 4 hereof, including all registration
and filing fees, listing





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fees for the Shares, printing expenses, fees and disbursements of counsel for
PSC, and blue sky fees and expenses in all states; except as provided in
Section 4(f) which costs shall be paid by the Investors.

         "Registrable Securities" means all Shares and any Common Stock issued
or issuable in respect of the Shares pursuant to any stock split, stock
dividend, recapitalization, or similar event; provided, however, that
Registrable Securities shall cease to be Registrable Securities when they may
be sold pursuant to Rule 144 under the Securities Act or are otherwise sold or
transferred by a Shareholder.  Notwithstanding the foregoing, transfers by an
Investor to a revocable inter vivos trust for estate planning purposes or by
will or the laws of descent and distribution shall not prevent Shares which are
otherwise Registrable Securities from ceasing to qualify as such.

         "Registration Statement" means any registration statement of PSC which
covers any of the Registrable Securities pursuant to the provisions of this
Agreement, including the Prospectus, amendments and supplements to such
registration statement, including post-effective amendments, all exhibits, and
all materials incorporated by reference or deemed to be incorporated by
reference in such registration statement.

         "Rule 144" means Rule 144 under the Securities Act, as such Rule may
be amended from time to time, or any similar rule or regulation hereafter
adopted by the Commission (excluding Rule 144A).

         "Securities Act" means the Securities Act of 1933, as amended.

         2.      Registration of Securities

                 (a)      Registration Statement.  PSC shall prepare a
Registration Statement pursuant to Rule 415 (or any appropriate similar rule
that may be adopted by the Commission) under the Securities Act covering the
Registrable Securities held by the Investors (the "Registration") and shall use
its best efforts to file the Registration with the Commission not later than 30
days after the Closing Date (the "Filing Date").  The Registration shall be on
Form S-3 or another appropriate abbreviated or short form of registration
statement permitting registration of such Registrable Securities for resale by
such holders from time to time in the manner or manners designated by them
consistent with the






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terms of this Agreement (including, without limitation, one or more
underwritten offerings).

                 (b)      Effectiveness.  PSC shall use its best efforts to
cause the Registration to become effective under the Securities Act as soon as
practicable following the Filing Date.  Subject to the requirements of the
Securities Act including, without limitation, requirements relating to updating
through post-effective amendments or otherwise, PSC shall use its best efforts
to keep the Registration continuously effective until such time as any of the
Shares may first be eligible to be sold or traded pursuant to Rule 144 under
the Securities Act; provided however, that if so requested by a majority of the
then outstanding Registrable Securities PSC shall agree to extend the period by
which the Registration remains effective to the same extent that "Suspension
Periods" are imposed pursuant to subsection 2(c) below,  but only so long as
the then outstanding Registrable Securities are too numerous to be sold under
the volume limitation of Rule 144 for an applicable three month period.  PSC
shall use its best efforts to take such actions under the laws of various
states as may be required to cause the resale of the Shares pursuant to the
Registration to be lawful.

                 (c)      Following the effectiveness of a Registration
Statement filed pursuant to this section, PSC may, at any time, suspend the
effectiveness of such Registration for up to 60 days, as appropriate (a
"Suspension Period"), by giving notice to each Investor, if PSC shall have
determined that PSC may be required to disclose any material corporate
development which disclosure (i) may have a material adverse affect on PSC,
(ii) may have a material adverse affect on the transaction or matter to be
disclosed, or (iii) would be detrimental to PSC or its shareholders.
Notwithstanding the foregoing, no more than two Suspension Periods (i.e., 120
days) may occur in immediate succession.  PSC shall use its best efforts to
limit the duration and number of any Suspension Periods.  Each Investor agrees
that, upon receipt of any notice from PSC of a Suspension Period, such Investor
shall forthwith discontinue disposition of shares covered by such Registration
Statement or prospectus until such Investor (i) is advised in writing by PSC
that the use of the applicable prospectus may be resumed, (ii) has received
copies of a supplemental or amended prospectus, if applicable, and (iii) has
received copies of any additional or supplemental filings which are
incorporated or deemed to be incorporated by reference in such prospectus.






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         3.      Expenses of Registration.  All Registration Expenses shall be
borne by PSC; provided, however, that the term Registration Expenses shall not
include, and in no event will PSC be obligated to pay, expenses and fees of
counsel for the Investors, stock transfer taxes or underwriters' discounts or
commissions relating to Registrable Securities.

         4.      Obligations of PSC.  To effect the registration of the
Registrable Securities, PSC shall, as expeditiously as reasonably possible.

                 (a)      Prepare and file with the Commission such amendments
and supplements to a Registration Statement with respect to the Registrable
Securities and the prospectus used in connection with such Registration
Statement as may be necessary to comply with the provisions of the Securities
Act with respect to the disposition of all securities covered by such
Registration Statement.

                 (b)      Furnish to the Investors such numbers of copies of
the Registration Statement, including all amendments or supplements thereto,
and of the Prospectus included in such Registration Statement, including a
preliminary prospectus, in conformity with the requirements of the Securities
Act, and such other documents as they may reasonably request in order to
facilitate the disposition of Registrable Securities owned by them.

                 (c)      Use its best efforts to register and qualify the
securities covered by such Registration Statement under such other securities
or blue sky laws of such jurisdictions as shall be reasonably requested by the
Investors, provided that, unless required by the Securities Act, PSC shall not
be required in connection therewith or as a condition thereto to qualify to do
business or to file a general consent to service of process in any such states
or jurisdictions in which PSC is not already qualified to do business or
subject to service of process.

                 (d)      Notify the Investors, the sales or placement agent,
if any, and the underwriter, if any, and confirm such advice in writing (i)
when a Registration Statement, including without limitation any amendments or
supplements, has been filed, and when such Registration Statement or any
post-effective amendment has become effective, (ii) of any comments by the
Commission and by the blue sky or securities commissioner or regulator of any
state with respect thereto or any request by the Commission for amendments or





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supplements to a Registration Statement or Prospectus or for additional
information, (iii) of the issuance by the Commission of any stop order
suspending the effectiveness of a Registration Statement or the initiation or
threatening of any proceedings for that purpose or of any order preventing or
suspending the use of any preliminary prospectus, (iv) of the receipt by PSC of
any notification with respect to the suspension of the qualification of the
Registrable Securities for sale in any jurisdiction or the initiation or
threatening of any proceeding for such purpose, or (v) at any time when a
Prospectus is required to be delivered under the Securities Act, that the
Registration Statement, Prospectus, Prospectus amendment or supplemental or
post-effective amendment, contains an untrue statement of a material fact or
omits to state any material fact required to be stated therein or necessary to
make the statements  therein not misleading in light of the circumstances
existing at that time.

                 (e)      Use its best efforts to obtain the withdrawal of any
order suspending the effectiveness of a Registration Statement or any
post-effective amendment at the earliest practicable date.

                 (f)      Furnish, at the request of any Investor requesting
registration of Registrable Securities pursuant to this Agreement, on the date
such Registrable Securities are delivered to the underwriters for sale in
connection with the Registration, if such securities are being sold through
underwriters, on the date the Registration Statement with respect to such
securities becomes effective, (i) an opinion, dated such date, of the counsel
representing PSC for the purposes of such registration, in form and substance
as is reasonably agreed to by such counsel and the underwriters in an
underwritten public offering regarding the due issuance and valid registration
of the Registrable Securities, addressed to the underwriters in an underwritten
public offering, if any, and (ii) a letter, dated such date, from the
independent accountants of PSC, in form and substance as reasonably agreed to
by independent accountants and the underwriters in an underwritten public
offering, addressed to the underwriters, if any.  To the extent reasonably
requested, copies of such letters shall be delivered to the Investors.  Upon
request by PSC, the Investors engaging such underwriter shall promptly
reimburse PSC for its costs and expenses of engaging such counsel and
accountants.

         5.      Indemnification.





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                 (a)      PSC will, and does hereby undertake to, indemnify and
hold harmless each Investor, each underwriter participating in a public
distribution of the Registrable Securities, each of such Investor's officers,
directors, partners and agents, and each Person controlling such Investor, with
respect to any registration, qualification, or compliance effected pursuant to
this Agreement, against all claims, losses, damages, and liabilities (or
actions in respect thereto) to which they may become subject under the
Securities Act, the Exchange Act, or other federal or state law arising out of
or based on (i) any untrue statements (or alleged untrue statement) of a
material fact contained in any prospectus, offering circular, or other similar
document (including any related Registration Statement, notification, or the
like) incident to any such registration, qualification, or compliance, or based
on any omission (or alleged omission ) to state therein a material fact
required to be stated therein or necessary to make the statements therein not
misleading, or (ii) any violation or alleged violation by PSC of any federal,
state or common law rule or regulation applicable to PSC in connection with any
such registration, qualification, or compliance, and will reimburse, as
incurred, each such Investor, each such underwriter, and each such director,
officer, partner, agent and controlling person, for any legal and any other
expenses reasonably incurred in connection with investigating or defending any
such claim, loss, damage, liability, or action; provided that PSC will not be
liable in any such case to the extent that any such claim, loss, damage,
liability or expense, arises out of or is based on any untrue statement or
omission based upon written information furnished to PSC by an instrument duly
executed by such Investor and stated to be specifically for use therein.

                 (b)      Each Investor will, if Registrable Securities held by
or issuable to such Investor are included in such registration, qualification,
or compliance, indemnify PSC, each of its directors, and each officer who signs
a Registration Statement in connection therewith, and each person controlling
PSC, and each other Investor, each of such other Investor's officers, partners,
directors and agents and each person controlling such other Investor, against
all claims, losses, damages, and liabilities (or actions in respect thereof)
arising out of or based on any untrue statement (or alleged untrue statement)
of a material fact contained in any such Registration Statement, prospectus,
offering circular, or other document, or any omission (or alleged omission) to
state therein a material fact required to be stated therein or necessary to
make the





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statements therein not misleading, and will reimburse, as incurred, PSC, each
such other Investor, and each such director, officer, partner, and controlling
person, for any legal or any other expenses reasonably incurred in connection
with investigating or defending any such claim, loss, damage, liability, or
action, in each case to the extent, but only to the extent, that such untrue
statement (or alleged untrue statement) or omission (or alleged omission) was
made in such Registration Statement, prospectus, offering circular, or other
document, in reliance upon and in conformity with written information furnished
to PSC by an instrument duly executed by such Investor and stated to be
specifically for use therein.

                 (c)      Each party entitled to indemnification under this
Section 5 (the "Indemnified Party") shall give notice to the party required to
provide such indemnification (the "Indemnifying Party") of any claim as to
which indemnification may be sought promptly after such Indemnified Party has
actual knowledge thereof, and shall permit the Indemnifying Party to assume the
defense of any such claim or any litigation resulting therefrom; provided that
counsel for the Indemnifying Party, who shall conduct the defense of such claim
or litigation, shall be subject to approval by the Indemnified Party (whose
approval shall not be unreasonably withheld) and the Indemnified Party may
participate in such defense at the Indemnifying Party's expense if
representation of such Indemnified Party would be inappropriate due to actual
or potential differing interests between such Indemnified Party and any other
party represented by such counsel in such proceeding; and provided further that
the failure of any Indemnified Party to give notice as provided herein shall
not relieve the Indemnifying Party of its obligations under this Section 5,
except to the extent that such failure to give notice shall materially
adversely affect the Indemnifying Party in the defense of any such claim or any
such litigation.  No Indemnifying Party, in the defense of any such claim or
litigation, shall, except with the consent of each Indemnified Party, consent
to entry of any judgment or enter into any settlement that does not include as
an unconditional term thereof the giving by the claimant or plaintiff therein,
to such Indemnified Party, of a release from all liability in respect to such
claim or litigation.

         6.      Information by Investor.  Each Investor shall furnish to PSC
such information regarding such Investor and the distribution proposed by such
Investor as PSC may reasonably request in writing and as shall be required in





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connection with any registration, qualification, or compliance referred to in
this Agreement.  Failure by the Investors to timely supply such information
will delay the filing of the Registration and will act to postpone the Filing
Date.

         7.      Delay of Registration.  No Investor shall have any right to
obtain or seek an injunction restraining or otherwise delaying any such
registration as the result of any controversy that might arise with respect to
the interpretation or implementation of this Agreement.

         8.      Rule 144 Reporting.  With a view to making available to the
Investors the benefits of certain rules and regulations of the Commission which
may permit the sale of the Registrable Securities to the public without
registration, PSC agrees, at its own costs, to use its best efforts to:

                 (a)      Make and keep public information available, as those
terms are understood and defined in Rule 144, as long as Registrable Securities
are outstanding;

                 (b)      File with the Commission, in a timely manner, all
reports and other documents required of PSC under the Securities Act and the
Exchange Act; and

                 (c)      So long as any Investor owns any Registrable
Securities, furnish to such Investor forthwith upon request:  a copy of the
most recent annual or quarterly report of PSC; and such other reports and
documents as such Investor may reasonably request in availing itself of any
rule or regulation of the Commission allowing it to sell any such securities
without registration.

         9.      Miscellaneous.

                 9.1      Waivers and Amendments.  With the written consent of
the Investors holding a majority of the Registrable Securities then
outstanding, the obligations of PSC and the rights of the Investors under this
Agreement may be waived (either generally or in a particular instance, either
retroactively or prospectively and either for a specified period of time or
indefinitely), and with the same consent PSC, when authorized by resolution of
its Board, may enter into a supplementary agreement for the purpose of adding
any provisions to or changing in any manner or eliminating any of the
provisions of this Agreement or of any supplemental agreement or modifying in
any manner the





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rights and obligations hereunder of the Investors and PSC.  Upon the
effectuation of each such waiver, consent or agreement of amendment or
modification, PSC agrees to give promptly written notice thereof to the
Investors who have not previously consented thereto in writing.  Neither this
Agreement nor any provision hereof may be changed, waived, discharged or
terminated orally or by course of dealing, but only by a statement in writing
signed by the party against which enforcement of the change, waiver, discharge
or termination is sought, except to the extent provided in this Section 9.1.
No waiver by any party of the breach of any term or provision contained in this
Agreement, in any one or more instances, shall be deemed to be, or construed
as, a further or continuing waiver of any such breach, or a waiver of the
breach of any other term or covenant contained in this Agreement.

                 9.2      Effect of Waiver or Amendment.  Each Investor
acknowledges that by operation of Section 9.1 hereof Investors holding a
majority of the Registrable Securities will, subject to the limitations
contained in such Section 9.1, have the right and power to diminish or
eliminate certain rights of such Investor under this Agreement.

                 9.3      Rights of Investors Inter Se.  Each Investor shall
have the absolute right to exercise or refrain from exercising any right or
rights which such Investor may have by reason of this Agreement including,
without limitation, the right to consent to the waiver of any obligation of PSC
under this Agreement and to enter into an agreement with PSC for the purpose of
modifying this Agreement or any agreement effecting any such modification, and
such Investor shall not incur any liability to any other Investor or Investors
with respect to exercising or refraining from exercising any such right or
rights.

                 9.4      Notices.  All notices, requests, consents and other
communications required or permitted hereunder shall be in writing and shall be
delivered, or mailed first class postage prepaid, registered or certified mail,

                 (a)  If to any Investor, addressed to such Investor at its
address shown on Annex A hereto, or at such other address as such Investor may
specify by written notice to PSC, or

                 (b)  If to PSC, at PSC's corporate headquarters, 620 Newport
Center Drive, Newport Beach, CA 92660 Attention: Mr. Richard V.  Plat,
Executive Vice President, or at such





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other address as PSC may specify by written notice to the Investors.

                          Each such notice, request, consent and other
communication shall for all purposes of the Agreement be treated as being
effective or having been given when delivered, if delivered personally, or, if
sent by mail, at the earlier of its actual receipt or three (3) days after the
same has been deposited in a regularly maintained receptacle for the deposit of
United States mail, addressed and postage prepaid as aforesaid.

                 9.5      Severability.  Should any one or more of the
provisions of this Agreement or of any agreement entered into pursuant to this
Agreement be determined to be illegal or unenforceable, all other provisions of
this Agreement and of each other agreement entered into pursuant to this
Agreement, shall be given effect separately from the provision or provisions
determined to be illegal or unenforceable and shall not be affected thereby.

                  9.6     Parties in Interest.  All the terms and provisions of
this Agreement shall be binding upon and inure to the benefit of and be
enforceable by the respective successors and assigns of the parties hereto,
whether so expressed or not.  Subject to the immediately preceding sentence,
this Agreement shall not run to the benefit of or be enforceable by any Person
other than a party to this Agreement and its successors and assigns.

                  9.7     Headings.  The headings of the sections, subsections
and paragraphs of this Agreement have been inserted for convenience of
reference only and do not constitute a part of this Agreement.

                  9.8     Choice of Law.  It is the intention of the parties
that the internal substantive laws, and not the laws of conflicts, of the State
of California should govern the enforceability and validity of this Agreement,
the construction of its terms and the interpretation of the rights and duties
of the parties.

                  9.9 Counterparts.  This Agreement may be executed in any
number of counterparts and by different parties hereto in separate
counterparts, with the same effect as if all parties had signed the same
document.  All such counterparts shall be deemed an original, shall be
construed together and shall constitute one and the same instrument.





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                 [REGISTRATION RIGHTS AGREEMENT SIGNATURE PAGE]



         IN WITNESS WHEREOF, each of the parties hereto has caused this
Agreement to be executed personally or by a duly authorized representative
thereof as of the day and year first above written.

                                       "PSC"

                                       PACIFIC SCIENTIFIC COMPANY,
                                       a California corporation


                                       By: /s/
                                           ------------------------------------
                                       Name:  Richard V. Plat
                                       Title: Executive Vice President



                                       "INVESTORS"


                                        /s/
                                        ---------------------------------------
                                        Name: Louis J. Petralli, Jr.


                                        /s/
                                        ---------------------------------------
                                        Name: Holger Sommer


                                        /s/
                                        ---------------------------------------
                                        Name: Ronald R. Siebert


                                        /s/
                                        ---------------------------------------
                                        Name: James R. Wittkopp


                                        /s/
                                        ---------------------------------------
                                        Name: Bill Petralli