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                                                                     Exhibit 4.1

                                ZYGO CORPORATION
                           2002 EQUITY INCENTIVE PLAN
1. Purpose. The purpose of the Zygo Corporation 2002 Equity Incentive Plan (the
"Plan") is to establish a flexible vehicle through which Zygo Corporation, a
Delaware corporation (the "Company"), can offer equity-based compensation
incentives to eligible personnel of the Company or any one or more of its
subsidiaries, affiliates or associated entities in order to attract, motivate
and retain such personnel and to further align the interests of such personnel
with those of the stockholders of the Company.

2. Types of Awards. Awards under the Plan may be in the form of (a) options to
purchase shares of the Company's common stock, $.10 par value per share ("Common
Stock"), including options intended to qualify as "incentive stock options"
("Incentive Stock Options") within the meaning of Section 422 of the Internal
Revenue Code of 1986, as amended (the "Code"), and options which do not qualify
as Incentive Stock Options ("Non Qualified Stock Options"), (b) restricted
shares of Common Stock, and (c) such other forms (if any) as may be permitted by
the Board of Directors of the Company (the "Board") pursuant to Section 8 of the
Plan.

3. Administration.

         (a) Committee. The Plan shall be administered by the Stock Option and
Compensation Committee (the "Committee") of the Board, provided that the Board
may, in its sole discretion, make awards under the Plan, and provided further
that, to the extent permitted by applicable law, the Board may, in its sole
discretion, delegate to an executive officer or officers of the Company the
authority to grant a specified number of options under the Plan, on such terms
and conditions as the Board shall establish from time to time, to employees or
consultants of the Company or its subsidiaries or affiliates who are not
officers or directors of the Company.

         (b) Authority of Committee. Subject to the limitations of the Plan, the
Committee, acting in its sole and absolute discretion, shall have full power and
authority to (i) select the persons to whom awards shall be made under the Plan,
(ii) make awards to such persons and prescribe the terms and conditions of such
awards, (iii) construe, interpret and apply the provisions of the Plan and of
any agreement or other document evidencing an award made under the Plan, (iv)
prescribe, amend and rescind rules and regulations relating to the Plan,
including rules governing its own operations, (v) correct any defect, supply any
omission and reconcile any inconsistency in the Plan, (vi) amend any outstanding
award in any respect, including, without limitation, to accelerate the time or
times at which the award becomes vested, unrestricted or may be exercised, (vii)
carry out any responsibility or duty specifically reserved to the Committee
under the Plan, and (viii) make any and all determinations and interpretations
and take such other actions as may be necessary or desirable in order to carry
out the provisions, intent and purposes of the Plan. A majority of the members
of the Committee shall 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. All decisions of the Committee pursuant to the
provisions of the Plan, including questions of construction, interpretation and
administration, shall be final, conclusive and binding on all persons.

         (c) Indemnification. To the maximum extent permitted by law, the
Company shall indemnify and hold harmless each member of the Committee and any
employee or director of the Company to whom any duty or power relating to the
administration or interpretation of the Plan is delegated from and against any
loss, cost, liability (including any sum paid in settlement of a claim with the
approval of the Board), damage and expense (including legal and other expenses
incident thereto) arising out of or incurred in connection with the Plan, unless
and except to the extent it shall be judicially determined, and from which no
appeal is available, that any such loss, cost, liability, damage or expense is
attributable to such person's fraud or willful misconduct.


4. Share Limitations.

         (a) Aggregate Award Limitation. Subject to adjustment pursuant to
Section 11 of the Plan, the aggregate number of shares of Common Stock that may
be issued under the Plan is 1,500,000. For this







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purpose, the following shares shall be deemed not to have been issued and shall
be deemed to remain available for issuance: (i) shares covered by the
unexercised portion of an option that terminates, expires or is canceled, (ii)
shares of restricted stock that are forfeited or repurchased in accordance with
the terms of the award, (iii) shares represented by other-equity based awards
that are forfeited, canceled or otherwise terminated, and (iv) shares that are
withheld in order to pay the purchase price for shares covered by any award or
to satisfy the tax withholding obligations associated with any award under the
Plan. Shares of Common Stock available for issuance under the Plan may be
authorized and unissued, held by the Company in its treasury or otherwise
acquired for purposes of the Plan. No fractional shares of Common Stock shall be
issued under the Plan.

         (b) Individual Award Limitation. Subject to adjustment pursuant to
Section 11 of the Plan, the maximum number of shares of Common Stock with
respect to which options may be granted under the Plan to any employee during
any calendar year shall be 75,000.

5. Eligibility. Awards under the Plan may be made to such current or future
employees, directors or consultants and other individuals who perform (or are
expected to perform) services for, or contribute (or are expected to contribute)
value to, the Company or any one or more of its subsidiaries, affiliates or
associated entities (collectively with the Company, the "Company Group"), all as
the Committee may select. In making awards under the Plan, the Committee may
give consideration to the functions and responsibilities of a potential
recipient, the potential recipient's previous and/or expected future
contributions to the business of any member of the Company Group and such other
factors as the Committee deems relevant under the circumstances.

6. Stock Options. Subject to the provisions of the Plan, the Committee may grant
options to eligible personnel upon such terms and conditions as the Committee
deems appropriate. The terms and conditions of any option shall be evidenced by
a written option agreement or other instrument approved for this purpose by the
Committee.

         (a) Exercise Price. The exercise price per share of Common Stock
covered by an option granted under the Plan may not be less than the par value
per share on the date of grant, provided that, in the case of an Incentive Stock
Option, the exercise price may not be less than the Fair Market Value (as
defined in Section 9 of the Plan) per share on the date of grant (or, in the
case of an Incentive Stock Option granted to an optionee who, at the time the
option is granted, owns stock possessing more than ten percent (10%) of the
total combined voting power of all classes of stock of the Company or a
"subsidiary" or "parent" of the Company within the meaning of Section 424 of the
Code, 110% of such Fair Market Value).

         (b) Term of Options. No option granted under the Plan may be
exercisable (if at all) more than ten (10) years after the date the option is
granted (or, in the case of an Incentive Stock Option granted to a ten percent
(10%) stockholder within the meaning of Section 424 of the Code, five (5)
years).

         (c) Exercisability of Options. Subject to the provisions of the Plan,
the Committee may establish such vesting and other conditions and restrictions
on the exercise of an option and/or upon the issuance of Common Stock in
connection with the exercise of an option as it deems appropriate. Unless the
Committee determines otherwise, an option will become vested and exercisable in
annual one-quarter increments on the first, second, third, and fourth
anniversaries of the date thereof, subject to the optionee remaining in the
continuous employment or other service with the Company Group, all as determined
by the Committee, following the date of grant.

         (d) Method of Exercise. Once vested and exercisable, an option may be
exercised by transmitting to the Company (i) a notice specifying the number of
shares to be purchased and (ii) payment of the aggregate exercise price of the
shares so purchased in cash or its equivalent, and any taxes due thereon in
accordance with Section 12 of the Plan, as determined by the Committee. As
determined by the Committee, in its sole discretion, payment of the exercise
price of an option in whole or in part may also be made (1) if the Common Stock
is publicly traded, by means of any cashless exercise procedure approved by the
Committee, (2) in the form of unrestricted shares of Common Stock which, (x) in
the case of shares acquired upon exercise of an option, have been owned by the
optionee for more than six (6) months on the date of surrender, and (y) have a
Fair Market Value on the date of surrender equal to the aggregate exercise price
of the shares of Common Stock as to which such option shall be exercised, (3)
any other form of consideration approved by the Committee and permitted by
applicable law (including a promissory note of






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the optionee) which the Committee determines to be consistent with the purposes
of the Plan or (4) any combination of the foregoing.

         (e) Termination of Employment or other Service. Unless otherwise
determined by the Committee at grant or, if no rights of the optionee are
thereby reduced, thereafter, the following rules apply with regard to options
held by an optionee at the time of his or her termination of employment or other
service with the Company Group:


              (i) Termination by Reason of Death. If an optionee's employment or
other service with the Company Group is terminated due to his or her death, then
(1) that portion of an option, if any, which is exercisable on the date of
termination shall remain exercisable by the optionee's beneficiary during the
one year period following the date of termination but in no event after
expiration of the stated term thereof and, to the extent not exercised during
such period, shall thereupon terminate, and (2) that portion of an option, if
any, which is not exercisable on the date of termination shall thereupon
terminate.

              (ii) Termination for Cause. If an optionee's employment or other
service is terminated by the Company Group for Cause (or at a time when grounds
for a termination for Cause exist), then, notwithstanding anything to the
contrary contained herein, any option held by the optionee (whether or not
otherwise exercisable) shall immediately terminate and cease to be exercisable.
A termination for "Cause" means (1) in the case where there is no employment,
consulting or similar service agreement between the optionee and the Company
Group or where such an agreement exists but does not define "cause" (or words of
like import), a termination classified by the Company Group, in its sole
discretion, as a termination due to the optionee's dishonesty, fraud,
insubordination, willful misconduct, refusal to perform services or materially
unsatisfactory performance of duties, or (2) in the case where there is an
employment, consulting or similar service agreement between the optionee and the
Company Group that defines "cause" (or words of like import), a termination that
is or would be deemed for "cause" (or words of like import) as classified by the
Company Group, in its sole discretion, under such agreement.

              (iii) Other Termination. If an optionee's employment or other
service with the Company Group terminates for any reason other than those
described in Section 6(e)(i) or 6(e)(ii) above, then: (1) that portion of an
option, if any, which is exercisable on the date of termination shall remain
exercisable by the optionee during the ninety (90) day period following the date
of termination but in no event after expiration of the stated term thereof and,
to the extent not exercised during such period, shall thereupon terminate, and
(2) that portion of an option, if any, which is not exercisable on the date of
termination shall thereupon terminate. Notwithstanding the preceding sentence
and the provisions of Section 6(e)(i) above, if (A) upon the termination of an
optionee's employment or other service with the Company Group for any reason at
or after the optionee shall have attained age fifty-five (55) other than a
termination by the Company Group for Cause (or a termination at a time when
grounds for a termination for Cause exist), and (B) the optionee shall then have
completed not less than five (5) years of employment or other service with the
Company Group, then the optionee's options shall become fully exercisable and
shall remain exercisable for the three (3) year period commencing on the date of
such termination, but in no event after expiration of the stated term thereof,
and to the extent not exercised during such period, shall thereupon terminate.

         (f) Rights as a Stockholder. No shares of Common Stock shall be issued
in respect of the exercise of an option until full payment of the exercise price
and the applicable tax withholding obligation with respect to such exercise has
been made or provided for. The holder of an option shall have no rights as a
stockholder with respect to any shares covered by an option until the date such
shares are issued.

         (g) Buy Out and Settlement. The Committee, on behalf of the Company,
may at any time offer to buy out any outstanding option on such terms and
conditions as the Committee shall establish.

7. Restricted Stock. Subject to the provisions of the Plan, the Committee may
award restricted shares of Common Stock to eligible personnel upon such terms
and subject to such conditions and restrictions as the Committee deems
appropriate. The terms and conditions of any restricted stock award shall be
evidenced by a written agreement or other instrument approved for this purpose
by the Committee.

         (a) Purchase Price. The purchase price payable for shares of restricted
stock may be as low as zero, provided, however, that to the extent required by
applicable law, the purchase price per share shall be





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no less than the par value of a share of Common Stock. In the sole discretion of
the Committee, loans may be made to a recipient in connection with the purchase
of restricted stock.

         (b) Restrictions and Vesting. The Committee may establish such
conditions and restrictions on the vesting of restricted stock as it deems
appropriate, including, without limitation, conditions and restrictions based
upon continued service, the attainment of specified performance goals and/or
other factors and criteria deemed relevant for this purpose.

         (c) Rights as a Stockholder. The recipient of restricted stock shall
have the rights of a stockholder with respect to the restricted stock, subject
to any restrictions and conditions as the Committee may impose.

         (d) Stock Certificates for Restricted Stock. Unless the Committee
elects otherwise, shares of restricted stock shall be evidenced by book entries
on the Company's stock transfer records pending the expiration of restrictions
thereon. If a stock certificate for shares of restricted stock is issued, it
shall bear an appropriate legend to reflect the nature of the restrictions
applicable to the shares represented by the certificate, and the Committee may
require that any or all such stock certificates be held in custody by the
Company until the applicable restrictions have lapsed. The Committee may
establish such other conditions as it deems appropriate in connection with the
issuance of certificates for shares of restricted stock, including, without
limitation, a requirement that the recipient deliver a duly signed stock power,
endorsed in blank, for the shares covered by the award.

         (e) Lapse of Restrictions. If and when the vesting conditions and other
restrictions applicable to a restricted stock award are satisfied or expire and
upon the recipient's payment of any taxes due thereon in accordance with Section
12 of the Plan, a certificate for the shares covered or referenced by the award,
to the extent vested and free of restrictions, shall be delivered to the holder.
All legends shall be removed from said certificates at the time of delivery
except as otherwise required by applicable law.

         (f) Termination of Employment or Other Service. Unless otherwise
determined by the Committee at grant or, if no rights of the recipient are
thereby reduced, thereafter, upon the termination of a recipient's employment or
other service for any reason or no reason, any shares of restricted stock which
have not yet become fully vested shall be forfeited, and any certificate
therefor or book entry with respect thereto or other evidence thereof shall be
canceled.

8. Other Equity-Based Awards. Without further action by the stockholders of the
Company, the Board may, in its sole discretion, amend the Plan to authorize the
Committee to grant other types of equity-based awards under the Plan, including,
without limitation, the grant or offer for sale of unrestricted shares of Common
Stock and/or the grant of restricted stock units, stock appreciation rights and
dividend equivalents, in such amounts and subject to such terms and conditions
as the Committee shall determine. Such awards may entail the transfer of actual
shares of Common Stock to recipients, or payment in cash or otherwise of amounts
based on the value of shares of Common Stock and may include, without
limitation, awards designed to comply with or take advantage of the applicable
local laws or jurisdictions other than the United States.

9. Fair Market Value. For purposes of the Plan, "Fair Market Value" on any date
shall be equal to the closing sale price per share as published by a national
securities exchange or NASDAQ National Market on which shares of the Common
Stock are traded on such date or, if there is no sale of Common Stock on such
date, the average of the bid and asked prices on such exchange at the closing of
trading on such date or, if shares of the Common Stock are not listed on a
national securities exchange or NASDAQ National Market on such date, the closing
price or, if none, the average of the bid and asked prices in the over the
counter market at the close of trading on such date, or if the Common Stock is
not traded on a national securities exchange or NASDAQ National Market or the
over the counter market, the fair market value of a share of the Common Stock on
such date as determined in good faith by the Committee.

10. Non-Transferability. Stock options granted under the Plan may not be
transferred by the optionee other than upon the optionee's death to a
beneficiary designated by the optionee in a manner acceptable to the Committee,
or, if no designated beneficiary shall survive the optionee, pursuant to the
optionee's will or by the laws of descent and distribution. All stock options
shall be exercisable during the optionee's lifetime only by the optionee (or, in
the event of the optionee's incapacity, his or her guardian or legal
representative). Shares of restricted stock granted under the Plan may not be
transferred prior to the date on






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which shares are issued or, if later, the date on which such shares have vested
and are free of any applicable restriction imposed hereunder. Except as
otherwise specifically provided by the provisions hereof or the applicable award
agreement or instrument, no award received under the Plan may be transferred in
any manner, and any attempt to transfer any such award shall be void, and no
such award shall in any manner be liable for or subject to the debts, contracts,
liabilities, engagements or torts of any person who shall be entitled to such
award, nor shall it be subject to attachment or legal process for or against
such person. Notwithstanding the foregoing, the Committee may determine at the
time of grant or thereafter that a stock option is transferable in whole or part
to such persons, under such circumstances, and subject to such conditions as the
Committee may prescribe.

11. Adjustments Upon a Capital Change. Upon any increase, reduction, or change
or exchange of the Common Stock for a different number or kind of shares or
other securities, cash or property by reason of a reclassification,
recapitalization, merger, consolidation, reorganization, stock split in the form
of a stock dividend, stock split or reverse stock split, combination or exchange
of shares, or any other similar corporate transaction or event that affects the
capitalization of the Company (a "Capital Change"), an equitable substitution or
adjustment may be made in (a) the aggregate number and/or kind of shares
reserved for issuance under the Plan, (b) the maximum number and/or kind of
shares with respect to which options may be granted under the Plan to any
employee during any calendar year, (c) the kind, number and/or exercise price of
shares or other property subject to outstanding options granted under the Plan,
and (d) the kind, number and/or purchase price of shares or other property
subject to outstanding awards of restricted stock or any other equity-based
awards granted under the Plan, in each case as may be determined by the Board,
in its sole discretion. Such other equitable substitutions or adjustments shall
be made as may be determined by the Board, in its sole discretion. Without
limiting the generality of the foregoing, in connection with a Capital Change,
the Board may provide, in its sole discretion, on a case by case basis, for: (A)
the cancellation of any outstanding awards (i) in exchange for payment in cash
or other property of the Fair Market Value of the shares of Common Stock covered
by such awards (whether or not otherwise vested or exercisable), reduced, in the
case of options, by the exercise price thereof, or (ii) for no consideration, in
the case (and to the extent) of awards which are not otherwise then vested or
exercisable; or (B) in the event of a liquidation or reorganization of the
Company (including a merger, consolidation or sale or distribution of assets of
the Company), the termination of any outstanding options upon notice given at
least thirty (30) days prior to the effective date of the transaction, provided
that such vested and exercisable options (or, in the Board's discretion, all
options whether or not otherwise vested or exercisable), shall be exercisable
until the effective date of such liquidation or reorganization in whole or in
part as to all shares then subject thereto. In the event of any adjustment in
the number of shares covered by any award pursuant to the provisions hereof, any
fractional shares resulting from such adjustment shall be disregarded, and each
such award shall cover only the number of full shares resulting from the
adjustment. All adjustments under this Section 11 shall be made by the Board,
and its determination as to what adjustments shall be made, and the extent
thereof, shall be final, binding and conclusive.

12. Tax Withholding. As a condition to the exercise of any award or the delivery
of any shares of Common Stock pursuant to any award or the lapse of restrictions
on any award, or in connection with any other event that gives rise to a federal
or other governmental tax withholding obligation on the part of the Company
Group relating to an award, (a) the Company Group may deduct or withhold (or
cause to be deducted or withheld) from any payment or distribution to an award
recipient whether or not pursuant to the Plan or (b) the Company Group shall be
entitled to require that the recipient remit cash to the Company Group (through
payroll deduction or otherwise), in each case in an amount sufficient in the
opinion of the Company to satisfy such withholding obligation. If the event
giving rise to the withholding obligation involves a transfer of shares of
Common Stock, then, at the sole discretion of the Committee, the recipient may
satisfy the withholding obligation described under this Section 12 by electing
to have the Company withhold shares of Common Stock (which withholding shall be
at a rate not in excess of the statutory minimum rate) or by tendering
previously-owned shares of Common Stock, in each case having a Fair Market Value
equal to the amount of tax to be withheld (or by any other mechanism as may be
required or appropriate to conform with local tax and other rules).

13. Amendment and Termination. The Board may amend or terminate the Plan,
provided, however, that no such action may affect adversely the rights of the
holder of any outstanding award without the consent of the holder. Except as
otherwise provided in Section 11 of the Plan, any amendment which would






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increase the number of shares of Common Stock which may be issued under the Plan
shall be subject to the approval of the Company's stockholders. The Committee
may amend the terms of any agreement or certificate made or issued hereunder at
any time and from time to time, provided, however, that no amendment which would
affect adversely the rights of the holder of any outstanding award may be made
without the consent of such holder.

14. General Provisions.

         (a) Compliance with Law. Shares of Common Stock shall not be issued
pursuant to the Plan unless the issuance and delivery of such shares pursuant
thereto shall comply with all relevant provisions of law, including, without
limitation, the Securities Act of 1933, as amended (the "Securities Act"), the
Exchange Act and the requirements of any stock exchange or market upon which the
Common Stock may then be listed, and shall be further subject to the approval of
counsel for the Company with respect to such compliance.

         (b) Investment Representation. The Committee may require each person
acquiring shares of Common Stock to represent to and agree with the Company in
writing that such person is acquiring the shares without a view to distribution
thereof. The certificates for such shares may include any legend that the
Committee deems appropriate to reflect any restrictions on transfer.

         (c) Transfer Orders; Placement of Legends. All certificates for shares
of Common Stock delivered under the Plan shall be subject to such stock-transfer
orders and other restrictions as the Committee may deem advisable under the
rules, regulations, and other requirements of the Securities and Exchange
Commission, any stock exchange or market upon which the Common Stock may then be
listed, and any applicable federal or state securities law. The Committee may
cause a legend or legends to be placed on any such certificates to make
appropriate reference to such restrictions.

         (d) No Employment or other Service Rights. Nothing contained in the
Plan or in any award agreement shall confer upon any recipient of an award any
right with respect to the continuation of his or her employment or other service
with any one or more of the Company Group or interfere in any way with the right
of the Company Group at any time to terminate such employment or other service
or to increase or decrease, or otherwise adjust, the other terms and conditions
of the recipient's employment or other service with the Company Group.

         (e) Decisions and Determinations Final. All decisions and
determinations made by the Board pursuant to the provisions hereof and, except
to the extent rights or powers under the Plan are reserved specifically to the
discretion of the Board, all decisions and determinations of the Committee,
shall be final, binding and conclusive on all persons.

         (f) Governing Law. All rights and obligations under the Plan and each
award agreement or instrument shall be governed by and construed in accordance
with the laws of the State of Delaware, without regard to its principles of
conflict of laws.

         (g) Term of the Plan. The Plan shall become effective upon its adoption
by the Board, subject to approval by the stockholders of the Company within
twelve (12) months of the date of such adoption. Unless sooner terminated by the
Board, the Plan shall terminate on the tenth anniversary of the date of its
adoption by the Board. The rights of any person with respect to an award made
under the Plan that is outstanding at the time of the termination of the Plan
shall not be affected solely by reason of the termination of the Plan and shall
continue in accordance with the terms of the award (as then in effect or
thereafter amended) and the Plan (as then in effect or thereafter amended).