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                                                                   EXHIBIT 10.20

         THE SECURITIES IN THE FORM OF NON-QUALIFIED STOCK OPTION OF CELL
ROBOTICS INTERNATIONAL, INC. HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT
OF 1933, AS AMENDED, OR UNDER ANY STATE SECURITIES LAWS. SUCH SECURITIES CANNOT
BE SOLD, TRANSFERRED, ASSIGNED OR OTHERWISE DISPOSED OF EXCEPT IN ACCORDANCE
WITH THE SECURITIES ACT OF 1933, AS AMENDED, AND APPLICABLE STATE SECURITIES
LAWS.


                        CELL ROBOTICS INTERNATIONAL, INC.
                            (A COLORADO CORPORATION)


Option No. NQ-2001-0601                            50,000 Shares of Common Stock


                       CERTIFICATE FOR COMMON STOCK OPTION


         This certifies that, for value received, PAUL C. JOHNSON, or registered
assigns ("Optionholder"), is the registered owner of this Option entitling the
Optionholder, subject to the provisions of Section 1 below, to subscribe for,
purchase and receive 50,000 shares of fully paid and non-assessable share of
Common Stock, $.004 par value, (the "Common Stock") of Cell Robotics
International, Inc., a Colorado corporation (the "Company"), upon presentation
and surrender of this Certificate and upon payment of the Exercise Price as
hereinbelow defined, for the shares of Common Stock of the Company, but only
subject to the conditions set forth herein. The Exercise Price, the number of
shares purchasable upon exercise of this Option, the number of shares subject to
this Option and the Expiration Date are subject to adjustments upon the
occurrence of certain events. The Optionholder may exercise all or any number of
shares of Common Stock subject to this Option. Upon exercise of this Option, the
form of election hereinafter provided for must be duly executed and the
instructions for registration of the Common Stock acquired by such exercise must
be completed. If the subscription rights represented hereby shall not be
exercised at or before the Expiration Date, this Option shall become and be void
without further force or effect, and all rights represented hereby shall cease
and expire.

         1        Vesting.

                  This Option shall be immediately exercisable and vested.

         2        Term of Option.


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                  This Option may be exercised in whole or in part commencing
upon June 15, 2001 and ending on June 15, 2006 (the "Expiration Date").

         3        Exercise Price.

                  This Option shall be exercisable to purchase 50,000 shares of
Common Stock of the Company at an Exercise Price equal to $0.71 per share (the
"Exercise Price"). The Exercise Price is subject to adjustment under certain
circumstances more fully describe in Sections 4 and 5 below.

         4.       Adjustments of Exercise Price and Shares.

                  (a) Subject to any required action by the shareholders of the
Company, the number of shares of Common Stock covered by this Option (as well as
the Exercise Price covered by this Option) shall be proportionately adjusted for
any increase or decrease in the number of issued shares of Common Stock
resulting from a stock split, payment of a stock dividend with respect to the
Common Stock or any other increase or decrease in the number of issued shares of
Common Stock effected without receipt of consideration by the Company. Such
adjustment shall be made by the Board of Directors in its sole discretion, which
adjustment shall be final, binding and conclusive. Except as expressly provided
herein, no issuance by the Company of shares of stock of any class shall affect,
and no adjustment by reason thereof shall be made with respect to, the number or
price of shares of Common Stock subject to this Option.

                  (b) In the event of the dissolution or liquidation of the
Company, other than pursuant to a Reorganization (hereinafter defined), this
Option shall terminate as of a date to be fixed by the Board of Directors,
provided that not less than 30 days written notice of the date so fixed shall be
given to the Optionholder and the Optionholder shall have the right during such
period to exercise this Option as to all or any part of the shares of Common
Stock covered hereby.

                  In the event of a Reorganization in which the Company is not
the surviving or acquiring company, or in which the Company is or becomes a
wholly-owned subsidiary of another company after the effective date of the
Reorganization, then

                  (i)      if there is no plan or agreement respecting the
                           Reorganization ("Reorganization Agreement") or if the
                           Reorganization Agreement does not specifically
                           provide for the change, conversion or exchange of the
                           shares of Common Stock under outstanding unexercised
                           options of the Company for securities of another
                           corporation, then the Board of Directors shall take
                           such action, and this Option shall terminate, as
                           provided above; or


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                  (ii)     if there is a Reorganization Agreement and if the
                           Reorganization Agreement specifically provides for
                           the change, conversion or exchange of the shares
                           under outstanding or unexercised options for
                           securities of another corporation, then the Board of
                           Directors shall adjust the shares of Common Stock
                           under this Option in a manner not inconsistent with
                           the provisions of the Reorganization Agreement for
                           the adjustment, change, conversion or exchange of
                           such options.

                  The term "Reorganization" as used in this Section 4(b) shall
mean any statutory merger, statutory consolidation, sale of all or substantially
all of the assets of the Company, or sale, pursuant to an agreement with the
Company, of securities of the Company pursuant to which the Company is or
becomes a wholly-owned subsidiary of another company after the effective date of
the Reorganization.

                  Except as provided above in this Section 4(b) and except as
otherwise provided by the Board of Directors in its sole discretion, this Option
shall terminate immediately prior to the consummation of such proposed action.

         5.       Adjustment to Exercise Price.

                  The Company may, in its sole discretion, lower the Exercise
Price at any time, or from time-to-time. When any adjustment is made in the
Exercise Price, the Company shall cause a copy of such statement to be mailed to
the Optionholder, as of a date within ten (10) days after the date when the
Exercise Price has been adjusted.

         6.       Manner of Exercise.

                  Subject to Section 4, the Optionholder of this Option
evidenced by this Certificate may exercise all or any whole number of such
Option prior to the Expiration Date in the manner stated herein. In connection
with the exercise of this Option, the purchase form provide for herein duly
executed by the Optionholder or by the Optionholder's duly authorized attorney,
plus payment of the Exercise Price applicable thereto, shall be surrendered to
the Company. If upon exercise of this Option the number shares covered by of
Options exercised shall be less than the total number of Option so evidenced,
then, subject to the terms hereof, the Optionholder shall continue to be
entitled to exercise that number of shares of Common Stock subject to this
Option that are not so exercised.

         7        Manner of Payment.

                  The payment of the Exercise Price of this Option shall be
paid, to the extent permitted by applicable statutes and regulations, either (i)
in cash at the time this Option is exercised, or (ii) by delivery to the Company
of other Common Stock of the Company valued at its then-established fair market
value (which Common Stock must have been owned by the


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Optionholder for at least six months prior to presentment), or (iii) in any
other form of legal consideration that may be acceptable to the Board of
Directors, in its discretion. For the purposes of this Section 7, the fair
market value of the Common Stock shall be (i) the closing sale price for the
Common Stock on the primary exchange upon which the shares are listed and traded
on the date this Option is exercised, or (ii) if the shares are not traded on
any national exchange, the closing sale price for the Common Stock on the NASDAQ
National Market on the date this Option is exercised, or (iii) if the shares or
neither traded on a national exchange nor listed on the NASDAQ National Market,
then the average of the bid and ask prices for the Common Stock in the
Over-The-Counter Market as quoted on the NASDAQ Small-Cap Market or (iv) if the
shares of Common Stock are neither traded on a national exchange or the NASDAQ
National Market nor quoted on the NASDAQ Small-Cap Market, the average of the
bid and ask prices for the Common Stock as quoted by any recognized securities
quotation service such as the National Quotation Bureau, Inc. or the OTC
Electronic Bulletin Board on the date this Option is exercised. In the case of
any deferred payment arrangement, any interest shall be payable at least
annually and shall be charged at the minimum rate of interest necessary to avoid
the treatment as interest, under any applicable provisions of the Internal
Revenue Code of 1986, as amended, of any amounts other than amounts stated to be
interest under the deferred payment arrangement.

         8.       Reservation of Common Stock.

                  The Company agrees that the number of shares of Common Stock
sufficient to provide for the exercise of this Option upon the basis herein set
forth will at all times during the term of this Option be reserved for the
exercise thereof.

         9        Issuance of Common Stock upon Exercise.

                  The Company, at its expense, shall cause to be issued, within
ten (10) days after exercise of this Option, a certificate or certificates in
the name requested by the Optionholder of the number of shares of Common Stock
to which the Optionholder is entitled upon such exercise. All shares of Common
Stock or other securities delivered upon the exercise of this Option shall be
validly issued, fully paid and non-assessable.

         10       No Right as Stockholder.

                  The Optionholder is not, by virtue of ownership of this
Option, entitled to any rights whatsoever of a shareholder of the Company.

         11       Assignment.

                  This Option may not be sold, pledged, assigned, hypothecated,
transferred or disposed of in any manner other than by will or by the laws of
descent and distribution or pursuant to a qualified domestic relations order as
defined by the Internal Revenue Code of 1986,


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as amended, or Title I of the Employee Retirement Income Security Act, or the
rules thereunder, and is not assignable by operation of law or subject to
execution, attachment or similar process. Except as otherwise provided herein,
this Option may be exercised during the Optionholder's lifetime only by the
Optionholder. Any attempted sale, pledge, assignment, hypothecation or other
transfer of this Option contrary to the provisions hereof and the levy of any
execution, attachment or similar process upon this Option shall be null and void
and without force or effect. No transfer of this Option by will or by the laws
of descent and distribution shall be effective to bind the Company unless the
Company shall have been furnished with written notice thereof and an
authenticated copy of the will and/or such other evidence as the Board of
Directors may deem necessary to establish the validity of the transfer and the
acceptance by the transferee or transferees of the terms and conditions of this
Certificate with respect to this Option. The terms of this Certificate shall be
binding upon the executors, administrators, heirs and successors of the
Optionholder.


Dated: June 15, 2001                 CELL ROBOTICS INTERNATIONAL, INC.
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/s/ Paul C. Johnson                  By:  /s/ Ronald K. Lohrding
---------------------                   ------------------------------
Optionholder


                                  PURCHASE FORM


                                                        Dated:____________, 200_


         Pursuant to the terms and provisions of the Certificate for Common
Stock Option dated ______________ (the "Certificate"), executed between me and
Cell Robotics International, Inc. (the "Company"), I hereby give notice that I
elect to exercise today the option (the "Option") evidenced by the Certificate
with respect to shares of the common stock of the Company (the "Option Shares").
Accordingly, I hereby agree to purchase such Option Shares at the price and
terms established under the Certificate.

         I understand that both the Option and any Option Shares purchased upon
its exercise are securities, the issuance of which by the Company requires
compliance with state and federal securities laws. I understand the Company
shall not be under any obligation to issue any Option Shares upon the exercise
of the Option unless and until the Company has determined that:

(i)      it has taken all actions required to register the Option Shares under
         the Securities Act of 1933, as amended, or to perfect an exemption from
         the registration requirements thereof, including, but not limited to
         any investment representation;


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(ii)     any applicable listing requirement of any stock exchange on which the
         Option Shares are listed has been satisfied; and

(iii)    all other applicable provisions of state and federal law have been
         satisfied.

         I hereby warrant that I am entitled under the Certificate to purchase
under the Option the number of Option Shares which I have agreed to purchase
herein.

                                      Sincerely,


                                      ----------------------------------------
                                                                  , Optionholder

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                     INSTRUCTIONS FOR REGISTRATION OF STOCK

Name
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                                    (please typewrite or print in block letters)
Address
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Signature
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