EXHIBIT 4.2

                               ZYGO CORPORATION
                      AMENDED AND RESTATED NON-QUALIFIED
                              STOCK OPTION PLAN

1. Purpose

     The purpose of the Zygo Corporation Amended and Restated Non-Qualified
Stock Option Plan (the "Non-Qualified Plan") is to aid Zygo Corporation and its
subsidiaries (the "Company") in attracting and retaining people of exceptional
ability by enabling selected individuals to purchase a proprietary interest in
the business, thereby stimulating in such individuals an increased desire to
render greater service, which will contribute to the continued growth and
success of the Company.

2. Amount and Source of Stock

     Except as otherwise permitted pursuant to paragraph 6 hereof, the total
number of shares of the Company's Common Stock, par value $.10 per share, which
may be issued under the Non-Qualified Plan shall not exceed 4,850,000 and may be
authorized and unissued shares, or may be issued and reacquired shares, as the
Board of Directors may from time to time determine. If an option shall expire or
terminate for any reason without having been exercised in full, the unpurchased
shares covered thereby shall be added to the shares otherwise available for
options under the Non-Qualified Plan.

3. Effective Date and Term of Plan

     The Non-Qualified Plan became effective on September 3, 1987, the date on
which it was initially approved by affirmative vote of the Board of Directors of
the Company. The term during which options may be granted under the
Non-Qualified Plan commenced on its effective date and, subject to the approval
of the stockholders of the Company, shall continue as hereby amended and
restated until September 3, 2002.

4. Administration and Eligibility

     (a) The Non-Qualified Plan will be administered by a committee (the
"Committee") consisting of at least two directors appointed by and serving at
the pleasure of the Board. If a Committee is not so established, the Board will
perform the duties and functions ascribed herein to the Committee. Each member
of the Committee shall be a "disinterested person" in accordance with the
applicable provisions of Rule 16b-3 under the Securities Exchange Act of 1934.
Subject to the provisions of the Non-Qualified Plan, the Committee, acting in
its sole and absolute discretion, will have full power and authority to grant
options under the Non-Qualified Plan, to interpret the provisions of the
Non-Qualified Plan and option agreements under the Non-Qualified Plan, to
supervise the administration of the Non-Qualified Plan, and to take such other
action as may be necessary or desirable in order to carry out the provisions of
the Non-Qualified Plan. A majority of the members of the Committee will
constitute a quorum. The Committee may act by the vote of a majority of its
members present at a meeting at which there is a quorum or by unanimous written
consent. The decision of the Committee as to any disputed question, including
questions of construction, interpretation and administration, will be final and
conclusive on all persons. The Committee will keep a record of its proceedings
and acts and will keep or cause to be kept such books and records as may be
necessary in connection with the proper administration of the Non-Qualified
Plan.

     (b) Options may be granted under the Non-Qualified Plan to present or
future key employees of the Company or a subsidiary of the Company and to
directors of the Company, whether or not they are employees of the Company. A
"key employee" is an officer or employee who has substantial responsibility in
the direction and management of the Company or any division, branch or
subsidiary.


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5. Options

     The terms and conditions of each option granted under the Non-Qualified
Plan shall be set forth in a Stock Option Agreement issued by the Company to the
optionee. Such terms and conditions shall include the following as well as such
other provisions, not inconsistent with the provisions of the Non-Qualified
Plan, as may be deemed advisable:

      (a)   The number of shares subject to the option.

      (b)   The purchase price per share.

      (c)   A provision that the full purchase price of shares purchased under
            the option shall be paid upon exercise thereof.

      (d)   A provision permitting exercise of the option either in whole or
            from time to time in part, but only for full shares.

      (e)   The dates after which the option may be exercised, in whole or in
            part.

      (f)   A provision for the termination of the option, not later than ten
            years from the date the option is granted, or prior thereto, if the
            optionee ceases to be a director of the Company or employed by the
            Company or a subsidiary thereof (otherwise than by reason of the
            optionee's death) unless extended by the Committee acting in its
            sole discretion (provided that no such extension shall result in an
            option having a term greater than ten years).

      (g)   A provision that the option shall not be transferrable other than by
            will or by the laws of descent and distribution and is exercisable
            during the lifetime of the optionee, only by him or her.

      (h)   A provision that the Company's obligation to sell and deliver stock
            under the option is subject to such compliance with federal and
            state laws, rules and regulations applying to the authorization,
            issuance or sale of securities as the Company deems necessary or
            advisable.

6. Adjustments Upon Changes in Stock

     If (i) the Company shall at any time be involved in a complete or partial
liquidation or reorganization, including a merger, consolidation, or sale or
distribution of assets, (ii) the Company shall declare a stock dividend or
subdivide or combine its Common Stock, or (iii) any other event shall occur
which in the judgment of the Board of Directors necessitates action by way of
adjusting the terms of the option, the Board of Directors shall forthwith take
any such action as in its judgment shall be necessary to preserve to the
optionee rights substantially proportionate to the rights existing prior to such
event or, in the case of a liquidation or reorganization, terminate the option
upon notice given at least thirty (30) days prior to the effective date of the
transaction, or provide for its assumption by any surviving, consolidated, or
successor corporation; provided, that in the event that the option is
terminated, the option shall be exercisable until the effective date of such
liquidation or reorganization in whole or in part as to all shares then subject
thereto, without regard to any installment exercise provisions. Notwithstanding
the foregoing, the right to exercise options without regard to any installment
exercise provisions shall not apply to any option holder who initiated the
transaction resulting in the application of this paragraph 6 unless such person
initiated the transaction pursuant to instructions or authority from the
Company. For the purpose of the foregoing, actions taken by members of an option
holder's family shall be deemed to have been taken by him.


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7. Amendment and Termination of the Plan

     The Board may amend or terminate the Non-Qualified Plan. Except as
otherwise provided in the Non-Qualified Plan with respect to equity changes, any
amendment which would increase the aggregate number of shares of Common Stock as
to which options may be granted under the Non-Qualified Plan, materially
increase the benefits under the Non-Qualified Plan, or modify the class of
persons eligible to receive options under the Non-Qualified Plan shall be
subject to the approval of the stockholders. No amendment or termination may
affect adversely any outstanding option without the written consent of the
optionee.

8.    Definition

     The term "parent" and "subsidiary" shall have the meaning ascribed to such
terms by Section 424 of the Internal Revenue Code of 1986, as amended.


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