<PAGE>
                                                                     EXHIBIT 4.1



                              COMPUTER MOTION, INC.
                            TANDEM STOCK OPTION PLAN

         THIS TANDEM STOCK OPTION PLAN (the "Plan") is adopted by COMPUTER
MOTION, INC., A CALIFORNIA CORPORATION (the "Company"), with reference to the
following facts:

                                    RECITALS:
                                    ---------

         A. The Company desires to issue shares of its common stock to certain
employees, consultants and independent contractors (the "Recipients") in order
to reward those Recipients for their contributions to the growth and profits of
the Company.

         B. To accomplish that goal, the Company is adopting this Plan to
establish the terms and conditions on which the Company shall issue to such
Recipients options to acquire the Company's common stock.

                                      PLAN:
                                      -----

         NOW, THEREFORE, the Company hereby adopts the following Plan:

1.       DEFINITIONS
         -----------

         The following terms shall have the meanings indicated below:

         1.1 "BOARD" means the Board of Directors of the Company.

         1.2 "CODE" means the Internal Revenue Code of 1986, as amended.

         1.3 "EMPLOYMENT TERMINATION DATE" means the date on which a Recipient
ceases to be employed by the Company for any reason.

         1.4 "EXERCISE DATE" means the date on which the Recipient delivers to
the Company a written notice that such Recipient elects to exercise an Option
with respect to some or all of the Shares of Stock subject to that Option.

         1.5 "EXPIRATION DATE" means, with respect to each Option, the date
specified by the Board as the last date on which the Option may be exercised.

         1.6 "GRANT DATE" means the date on which the Board grants an Option to
a Recipient pursuant to this Plan.

         1.7 "INCENTIVE OPTION" means an Option which satisfies the requirements
of Code Section 422.

         1.8 "NONQUALIFIED OPTION" means an Option which is not an Incentive
Option.

         1.9 "OPTION" means an option granted under this Plan to a Recipient
which entitles the Recipient to acquire Shares.
<PAGE>
         1.10 "OPTION TERM" means the period of time which commences on the
Grant Date and ends on the earlier of the Expiration Date or the date which is
thirty (30) days after the Recipient's Employment Termination Date, during which
the Recipient may exercise an Option granted to the Recipient pursuant to this
Plan.

         1.11 "RECIPIENT" means an employee, consultant or independent
contractor of the Company to whom an Option is granted pursuant to this Plan.

         1.12 "SHARES" means the shares of common stock of the Company.

         1.13 "VESTED PERCENTAGE" means, with respect to each Option, the
portion of the Option in which the Recipient has become vested, as determined
under Section 4.3.2, below.

         1.14 "VESTED SHARES" means, with respect to each Option the number of
Shares determined by multiplying (a) the total number of Shares subject to the
Option, times (b) the Recipient's Vested Percentage.

2.       COVERED OPTIONS
         ---------------

         2.1 TYPES OF OPTIONS. The Company may grant to Recipients either
Incentive Options or Nonqualified Options. Unless the Board of Directors
designates an Option as an Incentive Option at the time the Option is granted to
the Recipient, the Option shall be a Nonqualified Option.

         2.2 APPLICATION OF PLAN. Except as otherwise expressly provided in this
Plan, all the provisions of this Plan relate equally to both Incentive Options
and Nonqualified Options.

3.       RESERVATION OF SHARES
         ---------------------

         3.1 NUMBER OF SHARES RESERVED. The Company shall establish a Stock
Option Reserve ("Stock Option Reserve") to which it shall credit Three Million
(3,000,000) Shares of its authorized and unissued stock.

         3.2 ISSUANCE OF OPTIONS. The Company may not grant an Option to acquire
Shares unless there are credited to the Stock Option Reserve, immediately prior
to the grant of the Option, the number of Shares to which the Option is to
apply. If an Option is granted for a number of Shares which exceeds the number
of Shares then credited to the Stock Option Reserve, then the Option shall be
effective only with respect to the number of Shares then credited to the Stock
Option Reserve.

         3.3 ADJUSTMENT TO RESERVE. So long as this Plan is in effect, the
Company shall not issue any of the Shares credited to the Stock Option Reserve,
except pursuant to the exercise of Options granted under this Plan.

                  3.3.1 STOCK SPLIT, ETC. If the Company effects a subdivision
or consolidation of Shares or any other capital readjustment, the payment of a
stock dividend, a stock split or reverse stock split, or any other increase or
decrease in the number of the outstanding Shares without receiving compensation
therefor in money, services, or property, then the number of Shares then
credited to the Stock Option Reserve shall:

                           A. In the event of an increase in the number of
outstanding Shares, be proportionately increased;



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                           B. In the event of a decrease in the number of
outstanding Shares, be proportionately decreased.

                  3.3.2 GRANT AND EXERCISE OF OPTIONS. The number of Shares
credited to the Stock Option Reserve shall be (a) reduced by the number of
Shares for which Options are granted under this Plan and (b) increased, upon the
expiration or sooner termination of an Option, by the number of Shares which
were subject to that Option but for which the Option was not exercised.

4.       GRANT OF OPTIONS
         ----------------

         4.1 ELIGIBLE INDIVIDUALS. The Company may grant:

                  4.1.1 INCENTIVE OPTIONS. Incentive Options only to employees
of the Company; provided, a person who is a member of the Board of Directors of
the Company shall be eligible to receive an Incentive Option only if that person
also is an employee of the Company.

                  4.1.2 NONQUALIFIED OPTIONS. Nonqualified Options to any
employee, independent contractor or consultant of the Company.

         4.2 DISCRETIONARY TERMS. Subject to Section 4.3, below, the Board in
its discretion shall determine with respect to each Option granted under this
Plan:

                  4.2.1 RECIPIENTS. Those Recipients, if any, to whom Options
shall be granted under this Plan.

                  4.2.2 NUMBER OF SHARES. The number of Shares subject to the
Option;

                  4.2.3 PRICE. The purchase price per Share subject to each
Option; provided, if the Option is an Incentive Option, then:

                           A. The purchase price per Share shall be equal to the
fair market value of each such Share as of the Grant Date, as determined by the
Board in good faith; and

                           B. If the Recipient directly or indirectly owns stock
of the Company possessing more than ten percent (10%) of the total voting power
of all classes of stock of the Company or any parent corporation or subsidiary
of the Company, then (1) the purchase price for the Shares subject to the Option
shall be equal to or greater than one hundred ten percent (110%) of the fair
market value of such Shares as of the Grant Date, and (2) the Option Term for
such Option may not exceed five (5) years.

                  4.2.4 OTHER MATTERS.  Whether:

                           A. To impose on each Option terms and conditions
which are in addition to, or different from, those imposed on other Options; and

                           B. To require as a condition to the receipt of an
Option that the Recipient surrender any Options then held by the Recipient to
purchase Shares, whether pursuant to options previously granted to the Recipient
under an employee stock option plan or pursuant to any other option, warrant or
other right then held by the Recipient.




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<PAGE>
         4.3 MANDATORY TERMS. Each Option granted pursuant to this Plan shall be
subject to the following terms and conditions:

                  4.3.1 VESTED SHARES. A Recipient may exercise an Option at any
time only with respect to the number of Vested Shares under the Option.

                  4.3.2 VESTING. Unless a different schedule has been prescribed
by the Board at the time an Option is granted, an Option shall vest at a rate of
five percent (5%) per calendar quarter.

                  4.3.3 ASSIGNMENTS. No Option granted under this Plan may be
assigned or transferred, except by will or the laws of descent and distribution,
and during the life of the Recipient no Option shall be exercisable by any
person other than the Recipient.

                  4.3.4 LIMITS ON INCENTIVE OPTIONS. With respect to Incentive
Options only:

                           A. No Incentive Option granted under this Plan may be
exercised unless the Recipient to whom such Option was granted was an employee
of the Company (or a successor thereto pursuant to a transaction described in
Section 424 of the Code) at all times during the period beginning on the Grant
Date and ending no more than three (3) months prior to the date on which the
option is exercised (subject to the 30-day period set forth in Section 4.3.7,
below).

                           B. At no time shall the aggregate fair market value
(determined at the time the option is granted) of all Shares with respect to
which Incentive Options (whether they are Options granted under this Plan or are
incentive stock options granted under any other plan sponsored by the Company)
are exercisable for the first time by any employee during any calendar year,
exceed $100,000.

                           C. Each Incentive Option shall expire to the extent
it is not exercised within ten (10) years after the Grant Date.

                  4.3.5 TIME OF EXERCISE. Options may be exercised only once
during any calendar quarter and not more than four times in any calendar year.

                  4.3.6 PARTIAL EXERCISE. If a Recipient exercises an Option as
to some but not all the Shares which are subject to the Option, then the
remaining Shares subject to the Option shall continue to be subject to the
Option and may be purchased upon any subsequent exercise of the Option prior to
the end of the Option Term.

                  4.3.7 TERMINATION OF OPTION. If a Recipient of an Option who
is an employee terminates employment with the Company, then the Option shall
terminate on the earlier of (a) the Expiration Date, or (b) the date which is
thirty (30) days after the Recipient's Employment Termination Date; provided,
prior to termination the Recipient shall be entitled to exercise the Option with
respect to Vested Shares by delivering the Exercise Notice (as defined in
Section 5.1) to the Company prior to termination of the Option.

                  4.3.8 ADJUSTMENTS UPON CHANGES IN CAPITAL STRUCTURE. In the
event that the outstanding shares of common stock of the Company are increased
or decreased or changed into or exchanged for a different number or kind of
shares or other securities of the Company by reason of a recapitalization, stock
split, combination of shares, reclassification, stock dividend or other change
in the capital structure of the Company, then appropriate adjustment shall be
made by the Board to




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the number of Option Shares subject to the unexercised portion of this Option
and to the exercise price per share, in order to preserve, as nearly as
practical, but not to increase, the benefits of the Recipient under this Option.
Any such adjustment made by the Board shall be conclusive.

                  4.3.9 MERGERS, REORGANIZATIONS, ETC. In the event that the
Company at any time proposes to sell substantially all of its assets, merge
into, consolidate with or to enter into any other reorganization in which the
Company is not the surviving corporation, the Company shall cause either (a)
outstanding Options to be assumed by the successor corporation or (b) a new
option covering shares of the successor corporation of comparable value to
outstanding Options, with appropriate adjustments as to the number and kind of
shares and the exercise price, be granted to the Recipients. Upon such
assumption or substitution, the terms of the assumed or substituted Option shall
provide that if Recipient is terminated without cause by the successor
corporation all Options shall become immediately exercisable and remain
exercisable for a period of three (3) months after such termination.

                  4.3.10 RIGHTS AS SHAREHOLDER. No Recipient shall have any
rights as a shareholder of the Company with respect to any Share subject to an
Option until after (a) the Recipient has exercised the Option, and (b) there is
issued to the Recipient a stock certificate evidencing ownership of such share.
No adjustments shall be made for dividends or other rights for which the record
date is prior to the date such stock certificate is issued.

                  4.3.11 LISTING AND REGISTRATION. If at any time the Board
determines, in its discretion, that the listing, registration or qualification
of Options granted pursuant to the Plan, or the Shares to be sold and issued
upon exercise of such Options, upon any securities exchange or under any state
or federal law, or the consent or approval of any governmental regulatory body,
is necessary or desirable as a condition to or in connection with the granting
of Options pursuant to the Plan, or the sale of Shares upon the exercise of such
Options, then no further Options may be granted or Shares sold unless such
listing, registration, qualification, consent or approval shall have been
obtained free of any conditions not acceptable to the Board. The Board may cause
the Company, at its expense, to take any action related to the Plan which may be
required in connection with such listing, registration, qualification, consent
or approval.

                  4.3.12 STOCK OPTION AGREEMENT. Options granted under this Plan
shall be evidenced by a written Stock Option Agreement, substantially in the
form attached as Exhibit A to this Plan (in the case of Incentive Options), or
by a written Nonqualified Stock Option Agreement substantially in the form
attached as Exhibit B to this Plan (in the case of Nonqualified Options), and in
each case containing such additional terms and conditions consistent with the
provisions of the Plan as are imposed by the Board and which, in the opinion of
the Board, are necessary or desirable for the protection of the Company.

         4.4 NOTICE. The Board shall give written notice of any Option granted
under this Plan to the Recipient and to the Company within ten (10) days after
the Grant Date. Each such notice shall specify (a) the number of shares subject
to the Option, (b) the type of Option (Incentive or Nonqualified), (c) the
purchase price for Shares under the Option, (d) the Option Term and (e) the
times at which the Option may be exercised.






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5.       ISSUANCE OF SHARES
         ------------------

         5.1 NOTICE OF EXERCISE. To the extent that an Option may be exercised
with respect to Vested Shares under Section 4, above, such Option shall be
exercised only by the Recipient delivering to the Company a written notice (the
"Exercise Notice") stating the number of Shares with respect to which the Option
is being exercised.

         5.2 CLOSING. The closing of the purchase and sale of Shares pursuant to
the exercise of an Option shall occur at the offices of the Company on a
mutually agreeable date not more than thirty (30) days after the date on which
the Exercise Notice is delivered to the Company pursuant to Section 5.1, above
(or, if later, the third business day after the date on which the condition
specified in Section 5.2.1, below, is satisfied).

                  5.2.1 CONDITION PRECEDENT. The obligations of the parties at
the closing shall be subject to the Company's obtaining any permits,
qualifications or other consents that may be required under state or federal
securities laws in connection with the issuance of the Shares.

                  5.2.2    DELIVERIES AT CLOSING.  At the closing:

                           A.       The Recipient shall deliver:

                                    (1) The purchase price for the Shares being
purchased, either in cash or by certified or cashier's check or money order or,
in the discretion of the Company, a number of Shares having a fair market value
as of the date of the closing (as determined by the Board in good faith) equal
to the purchase price due the Company.

                                    (2) An executed Stock Transfer Agreement
pursuant to Section 6, below;

                                    (3) An executed Investment Letter, in
substantially the form set forth as Exhibit C to this Plan; and

                                    (4) Such other documents and instruments as
the Company reasonably may request to effect the closing in compliance with this
Plan and applicable law.

                           B.       The Company shall deliver:

                                    (1) One or more stock certificates
evidencing the Shares being purchased by the Recipient; and

                                    (2) An executed Stock Transfer Agreement
pursuant to Section 6, below.

         5.3 LEGEND. All certificates evidencing Shares purchased pursuant to
exercise of an Option shall be imprinted with such legends, if any, as may be
necessary to comply with applicable federal and State securities laws, and also
bear a legend in substantially the following form:




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                  THE SHARES OF STOCK EVIDENCED BY THIS CERTIFICATE ARE SUBJECT
         TO THE TERMS OF THAT CERTAIN STOCK TRANSFER AGREEMENT BETWEEN THE
         COMPANY AND (RECIPIENT) DATED ____________, 19___, A COPY OF WHICH IS
         AVAILABLE FOR INSPECTION AT THE OFFICES OF THE COMPANY.

         5.4 FAILURE TO COMPLETE PURCHASE. If, upon tender and delivery by the
Company at the closing of the stock certificates required pursuant to Section
5.2, above, the Recipient fails to accept delivery of and to pay for all or any
part of the number of Shares specified in the Exercise Notice, then the Board,
in its discretion, may terminate the Recipient's right to exercise the Option
with respect to such undelivered shares and any other Shares subject to the
Option.

         5.5 FULLY PAID SHARES. All Shares issued upon the exercise of Options
granted under this Plan shall be fully paid and nonassessable shares.

6.       RESTRICTIONS ON SHARE TRANSFER
         ------------------------------

         6.1 GRANT OF RIGHTS. With respect to all Shares purchased pursuant to
the exercise of an Option (the "Option Shares"), the Company shall have:

                  6.1.1 FIRST REFUSAL. A right of first refusal to purchase the
Option Shares prior to any sale, encumbrance, or other transfer, whether
voluntarily or by operation of law, other than a transfer to a revocable inter
vivos trust of which the Recipient is the trustor, trustee, and beneficiary, as
further described in Section 6.2, below; and

                  6.1.2 REPURCHASE OPTION. The right and option (the "Repurchase
Option"), but not the obligation, to purchase such Option Shares upon (a) the
termination of the Recipient's employment or other service engagement with the
Company for any reason, and (b) the death of the Recipient, as further described
in Section 6.3, below.

         6.2 FIRST REFUSAL RIGHTS. Prior to any transfer of any Option Shares,
the Recipient shall deliver to the Company a written notice (the "Transfer
Notice") describing (a) the name and address of the proposed transferee; (b) the
proposed purchase price; (c) the number of Option Shares to be sold or
transferred; and (d) the other terms and conditions of the transfer. Such
Transfer Notice shall be treated as an offer by the Recipient to sell the Option
Shares to the Company at the same price, and on the same other terms, as in the
proposed transfer described in the Transfer Notice.

                  6.2.1 EXERCISE. If the Company wishes to purchase the Option
Shares, then the Company shall deliver to the Recipient, within thirty (30) days
after receiving the Transfer Notice, a written acceptance of the offer. The
closing of the sale of the Option Shares to the Company thereafter shall occur,
at the offices of the Company, within thirty (30) days after the Company accepts
the Recipient's offer.

                  6.2.2 FAILURE TO EXERCISE. If the Company fails to deliver to
the Recipient within such 30-day period a written acceptance of the Recipient's
offer, then the Recipient may proceed with the proposed transfer to the proposed
transferee, and on the same terms and conditions, described in the Transfer
Notice. If such transfer fails to close within 60 days after the end of such
30-day period, then the Recipient shall be obligated to offer the Option Shares
to the Company





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pursuant to this Section 6.2 prior to transferring those Shares to the proposed
transferee or any other person.

         6.3 REPURCHASE OPTION. If a Recipient dies or the Recipient's
employment or other service engagement with the Company is terminated for any
other reason, then during the 90-day period after the occurrence of such event
(the "Marketing Period"), the Recipient shall have the opportunity to sell or
attempt to sell, to any purchaser at whatever price the Recipient is able to
negotiate, any Option Shares then owned by the Recipient. Any such sale or
attempted sale of those Option Shares shall be subject to the right of first
refusal described in Sections 6.1.1 and 6.2, above.

                  6.3.1 OPTION EXERCISE. If, during the Marketing Period, the
Recipient:

                           A. Delivers to the Company a Transfer Notice pursuant
to Section 6.2, above, describing a bona fide offer to purchase the Option
shares described in the notice, then the sale of such Option Shares shall be
governed by that Section. If the Company declines to exercise its right of first
refusal and the sale to the proposed transferee fails to close within the 60-day
period described in Section 6.2.2, above, then the Company thereafter shall be
entitled to exercise its Repurchase Option with respect to such Option Shares by
delivering to the Recipient, within 180 days after the end of such 60-day
period, a written notice of its election to exercise of that option (the
"Exercise Notice").

                           B. Fails to deliver to the Company a Transfer Notice
regarding a bona fide offer to purchase any Option Shares then held by the
Recipient, then the Company may exercise the Repurchase Option with respect to
those Option Shares by delivering an Exercise Notice to the Recipient within one
hundred eighty (180) days after the end of the Marketing Period.

                  6.3.2 CLOSING. The closing of the sale of the Option Shares to
the Company pursuant to the exercise of the Repurchase Option shall occur at the
offices of the Company on a mutually acceptable date within thirty (30) days
after delivery of the Exercise Notice.

                  6.3.3 PRICE. The purchase price for each of the Option Shares
shall be determined in accordance with this Section 6.3.3.

                           A. If the Shares:

                                    (1) Are then traded on an established
securities market, then the purchase price per Share shall be the closing bid
price per share of the Company's Stock quoted on the second business day prior
to the date of the closing; or

                                    (2) Are not then traded on an established
securities market, then the purchase price per Share shall be the greater of (a)
the net book value of such Shares as of the last day of the last calendar month
preceding the date of the closing, or (b) an amount determined by multiplying
ten (10) times the Company's earnings per Share during the twelve-month period
ending on the last day of the last full calendar month immediately preceding the
date of the closing.

                           B. The net book value per Share shall be determined,
by the Company's independent certified public accountant, by (1) first
allocating the book value of the Company to all of its outstanding capital stock
in such manner as that accountant deems appropriate, and (2) then dividing that
portion of such net book value allocable to all the Shares, by the number of
Shares outstanding on the last day of the last full calendar month preceding the
closing. The Company's net





                                      -8-
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book value shall be the excess of the amount of the Company's total assets over
the amount of the Company's total liabilities.

                           C. The Company's earnings per Share shall be
determined, by the Company's independent certified public accountant, by (1)
allocating the Company's earnings for the 12-month period described in Section
6.3.3.A(2)(b), above, to all the Company's outstanding capital stock in such
manner as that accountant deems appropriate, and (2) then dividing that portion
of such earnings allocable to all the Shares, by the number of Shares
outstanding on the last day of the 12-month period described in Section
6.3.3A(2)(b).

                           D. All such determinations shall be made in
accordance with generally accepted accounting principles applied on a basis
consistent with those previously applied by the Company.

         6.4 STOCK TRANSFER AGREEMENT. Concurrently with a Recipient's purchase
of Shares pursuant to the exercise of an Option, the Recipient and the Company
shall execute a Stock Transfer Agreement in substantially the form set forth at
Exhibit D, evidencing the right of first refusal and Repurchase Option described
in this Section 6.

7.       TERM AND AMENDMENT OF PLAN
         --------------------------

         7.1 TERM. Unless sooner terminated pursuant to Section 7.2, below, this
Plan shall have a term of ten (10) years and shall expire on the tenth (10th)
anniversary of (a) the date of its adoption by the Board, or (b) the date of its
approval by the shareholders of the Company, whichever first occurs.

         7.2 AMENDMENT AND TERMINATION. The Board in its sole and absolute
discretion may amend, suspend or terminate the Plan in whole or in part at any
time, but no such amendment, suspension or termination shall adversely affect
the rights or obligations of Recipients with respect to Options granted prior to
the date of any such amendment, suspension or termination; provided,
notwithstanding the foregoing, the shareholders shall be required to approve any
amendment which has the effect of (a) increasing the number of shares subject to
the Plan or (b) changing the designation of the class of employees eligible to
receive options under the Plan.

8.       MISCELLANEOUS
         -------------

         8.1 APPROVAL OF SHAREHOLDERS. This Plan shall be effective only if it
is approved by the shareholders of the Company within the period beginning
twelve (12) months before and ending within twelve (12) months after the date of
its adoption by the Board. Options may be granted under this Plan prior to the
date of its approval by the Company's shareholders, but no such Option may be
exercised until this Plan has been so approved by the shareholders. Upon such
approval, Options previously granted under this Plan shall be given effect
retroactive to their Grant Date.

         8.2 USE OF PROCEEDS. The proceeds from the sale of Shares pursuant to
Options granted under this Plan shall constitute general funds of the Company.

         8.3 NO RIGHT TO ALLOCATION. No person shall be entitled to receive an
Option under this Plan and no person shall have authority to enter into an
agreement for the granting of an Option or to make any representation or
warranty with respect thereto. No Options shall be earmarked for the





                                      -9-
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account of a Recipient nor shall a Recipient have any rights with respect to
such Options until such Options have been issued in accordance with the
provisions of this Plan.

         8.4 NO EMPLOYMENT RIGHTS. Neither the adoption of this Plan, nor any
action taken by the Board under the Plan, nor any provision of the Plan, shall
be construed as giving to any person the right to be retained in the employ of
the Company.

         8.5 NOTICES. All notices permitted or required by this Plan shall be in
writing and shall be deemed to be delivered and received (a) when personally
delivered, or (b) on the day on which telecopied, or (c) on the third (3rd)
business day after the day on which deposited in the United States mail,
first-class-certified mail, postage prepaid, transmitted or addressed to the
person for whom intended, at the telecopy number or address appearing on the
records of the Company, or such other telecopy number or address, notice of
which is given in the manner contemplated by this Section 8.5.

         8.6 GOVERNING LAW. The Plan shall be governed by the Internal Revenue
Code of 1986, as amended, and by the laws of the State of California.

         8.7 EFFECTIVE DATE. The effective date of this Plan shall be March 1,
1993.

EXHIBITS
--------

A        Stock Option Agreement (Incentive Options)

B        Stock Option Agreement (Nonqualified Options)

C        Form of Investment Letter

D        Stock Purchase Agreement




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