<PAGE>

                                                                    EXHIBIT 4.10

              CERTIFICATE TO SET FORTH DESIGNATIONS, VOTING POWERS,
              PREFERENCES, LIMITATIONS, RESTRICTIONS, AND RELATIVE
                        RIGHTS OF SERIES D 8% CONVERTIBLE
                    PREFERRED STOCK, $.01 PAR VALUE PER SHARE

         It is hereby certified that:

         I.       The name of the corporation is JMAR Technologies, Inc. (the
"CORPORATION"), a Delaware corporation.

         II.      The certificate of incorporation of the Corporation, as
amended, authorizes the issuance of 5,000,000 shares of Preferred Stock, $.01
par value per share, and expressly vests in the Board of Directors of the
Corporation the authority provided therein to issue all of said shares in one or
more Series by resolution or resolutions, to establish the designation and
number and to fix the relative rights and preferences of each series to be
issued.

         III.     The Board of Directors of the Corporation, pursuant to the
authority expressly vested in it, has adopted the following resolution creating
a class of Series D Preferred Stock:

         RESOLVED, that a portion of the authorized shares of Preferred Stock of
the Corporation shall be designated as a separate series possessing the rights
and preferences set forth below:

         1.       Designation: Number of Shares. The designation of said series
of Preferred Stock shall be Series D 8% Cumulative Convertible Preferred Stock
(the "SERIES D PREFERRED STOCK"). The number of shares of Series D Preferred
Stock shall be 200,000. Each share of Series D Preferred Stock shall have a
stated value equal to $10 (as adjusted for any stock dividends, combinations or
splits with respect to such shares) (the "STATED VALUE"), and $.01 par value.

         2.       Ranking. The Series D Preferred Stock shall rank (i) prior to
the Corporation's common stock, par value $.01 per share ("COMMON STOCK"); (ii)
prior to any class or series of capital stock of the Corporation hereafter
created (unless such class or series of capital stock specifically, by its
terms, ranks senior to or Pari Passu with the Series D Preferred Stock); (iii)
on a parity with any class or series of capital stock of the Corporation
hereafter created specifically ranking, by its terms, on parity with the Series
D Preferred Stock ("PARI PASSU SECURITIES"); and (iv) junior to any class or
series of capital stock of the Corporation hereafter created specifically
ranking, by its terms, senior to the Series D Preferred Stock ("SENIOR
SECURITIES"), in each case as to distribution of assets upon liquidation,
dissolution or winding up of the Corporation, whether voluntary or involuntary.

         3.       Dividends.

                  (a)      Subject to Section 3(d), the Holders of outstanding
shares of Series D Preferred Stock shall be entitled to receive preferential
dividends in cash out of any funds of the Corporation legally available at the
time for declaration of dividends before any dividend or other distribution will
be paid or declared and set apart for payment on any shares of any Common Stock,
or other class of stock presently authorized or to be authorized, other than the
Corporation's Series A, Series B and Series C Preferred Stock which shall be
Senior Securities (the Common Stock, and such other stock being hereinafter
collectively the "JUNIOR STOCK") at the rate of 8% simple interest per annum on
the Stated Value per share of Series D Preferred Stock (the "DIVIDEND RATE")
then outstanding (as adjusted pursuant to Section 4 below) payable monthly
commencing February 1,

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2004 and on the first business day of each consecutive calendar month
thereafter; provided, however, that dividend payments may be made in fully paid
and non assessable registered shares of the Corporation's Common Stock at the
Conversion Price (as defined herein) then in effect, and the issuance of such
additional shares shall constitute full payment of such dividend.

                  (b)      The dividends on the Series D Preferred Stock at the
rates provided above shall be cumulative whether or not earned so that, if at
any time full cumulative dividends at the rate aforesaid on all shares of the
Series D Preferred Stock then outstanding from the date from and after which
dividends thereon are cumulative to the end of the monthly dividend period next
preceding such time shall not have been paid or declared and set apart for
payment, or if the full dividend on all such outstanding Series D Preferred
Stock for the then current dividend period shall not have been paid or declared
and set apart for payment, the amount of the deficiency shall be paid or
declared and set apart for payment (but without interest thereon) before any sum
shall be set apart for or applied by the Corporation or a subsidiary of the
Corporation to the purchase, redemption or other acquisition of the Series D
Preferred Stock or Parri Passu Securities and before any dividend or other
distribution shall be paid or declared and set apart for payment on any Junior
Stock and before any sum shall be set aside for or applied to the purchase,
redemption or other acquisition of Junior Stock.

                  (c)      Dividends on all shares of the Series D Preferred
Stock shall begin to accrue and be cumulative from and after the date of
issuance thereof. A dividend period shall be deemed to commence on the day
following a monthly dividend payment date herein specified and to end on the
next succeeding monthly dividend payment date herein specified.

                  (d)      If a current registration statement covering the
Securities shall have been declared effective by the Securities Exchange
Commission, the Dividend Rate shall be decreased by fifty basis points (50 b.p.)
for each incremental increase of twenty five percent (25%) of the volume
weighted average price of the Common Stock for the five (5) trading days prior
to the first calendar day of the month, above the Conversion Price (defined
below) then in effect.

         4.       Liquidation Rights.

                  (a)      Upon the dissolution, liquidation or winding-up of
the Corporation, whether voluntary or involuntary, the Holders of the Series D
Preferred Stock shall be entitled to receive before any payment or distribution
shall be made on the Junior Stock, out of the assets of the Corporation
available for distribution to stockholders, the Stated Value per share of Series
D Preferred Stock then outstanding and all accrued and unpaid dividends to and
including the date of payment thereof. Upon the payment in full of all amounts
due to Holders of the Series D Preferred Stock, the holders of the Common Stock
of the Corporation and any other class of Junior Stock shall receive all
remaining assets of the Corporation legally available for distribution. If the
assets of the Corporation available for distribution to the holders of the
Series D Preferred Stock shall be insufficient to permit payment in full of the
amounts payable as aforesaid to the holders of Series D Preferred Stock upon
such liquidation, dissolution or winding-up, whether voluntary or involuntary,
then all such assets of the Corporation shall be distributed ratably among the
holders of the Series D Preferred Stock.

                  (b)      Neither the purchase nor the redemption by the
Corporation of shares of any class of stock nor the merger or consolidation of
the Corporation with or into any other corporation or corporations nor the sale
or transfer by the Corporation of all or any part of its assets shall be deemed
to be a liquidation, dissolution or winding-up of the Corporation for the
purposes of this Section 4.

         5.       Conversion into Common Stock. Shares of Series D Preferred
Stock shall have the following conversion rights and obligations:

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                  (a)      Subject to the further provisions of this Section 5,
each holder of shares of Series D Preferred Stock shall have the right at any
time commencing after the issuance of the Series D Preferred Stock to such
holder to convert such shares into fully paid and non-assessable shares of
Common Stock of the Corporation (as further subject to the limitation set forth
in Section 5(i) below) at the Conversion Price provided in Section 5(b) below.
All issued or accrued but unpaid dividends may be converted at the election of
the holder simultaneously with the conversion of the Series D Preferred Stock
being converted.

         Notwithstanding anything contained herein to the contrary, no holder of
Series D Preferred Stock shall be entitled to convert pursuant to the terms of
this Section 5(a) that amount of the Preferred Stock convertible into that
number of shares of Common Stock which would result in the Holder's beneficial
ownership (as defined below) of the Corporation's Common Stock being in excess
of 4.99% of the outstanding shares of Common Stock of the Company. For the
purposes of the immediately preceding sentence, beneficial ownership shall be
determined in accordance with Section 13(d) of the Exchange Act and Regulation
13d-3 thereunder. Subject to the foregoing, a holder of Series D Preferred Stock
shall not be limited to aggregate conversions of only 4.99%. A holder of Series
D Preferred Stock may void the conversion limitation described in this Section
5(a) upon 75 days prior notice to the Corporation or upon an Event of Default
hereunder.

                  (b)      The number of shares of Common Stock issuable upon
conversion of each share of Series D Preferred Stock shall equal (i) the sum of
(A) the Stated Value per share, as amended pursuant to Section 5 hereof, and (B)
at the holder's election, accrued and unpaid dividends on such share, divided by
(ii) $1.56 (the "CONVERSION PRICE").

                  If after the Default Notice Period (as defined below) the
Corporation has not repaid in full the amounts then due hereunder or cured the
Event of Default, then the Conversion Price shall be reduced and shall be equal
to the lower of (i) the Conversion Price; or (ii) eighty percent (80%) of the
average of the three (3) lowest closing prices for the Common Stock on whichever
Principal Market is at the time the principal trading exchange or market for the
Common Stock, or on any securities exchange or other securities market on which
the Common Stock is then being listed or traded, for the thirty (30) trading
days prior to but not including the Conversion Date.

                  (c)      The holder of any certificate for shares of Series D
Preferred Stock desiring to convert any of such shares may give notice of its
decision to convert the shares into common stock by delivering, along with the
certificate(s) representing the shares of Series D Preferred Stock to be
converted if requested by the Corporation, an executed and completed notice of
conversion ("NOTICE OF CONVERSION") to the Corporation (the "CONVERSION DATE").
Each date on which a notice of conversion is delivered or telecopied to the
Corporation in accordance with the provisions hereof shall be deemed a
Conversion Date. A form of Notice of Conversion that may be employed by a holder
is annexed hereto as Exhibit A. The Corporation will cause the transfer agent to
transmit the certificates representing the shares of the Corporation's Common
Stock issuable upon conversion of the Series D Preferred Stock (and a
certificate representing the balance of the Preferred Stock not so converted, if
requested by Purchaser) to the holder by (i) to the extent permitted by the
transfer agent for the Common Stock, crediting the account of the Holder's prime
broker with the Depository Trust Corporation ("DTC") through its Deposit
Withdrawal Agent Commission ("DWAC") system, or (ii) otherwise, by delivery to
the Holder of a stock certificate representing such shares of Common Stock,
within three (3) business days after receipt by the Corporation of the Notice of
Conversion and the certificate(s) representing the shares of Series D Preferred
Stock to be converted (the "DELIVERY DATE"). The Corporation is obligated to
deliver to the holder simultaneously with the aforedescribed Common Stock, at
the election of the

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Holder, additional Common Stock representing the conversion at the Conversion
Price, of dividends accrued on the Series D Preferred Stock being converted.

                  The Corporation understands that a delay in the delivery of
the Common Stock in the form required pursuant to this Section beyond the
Delivery Date could result in economic loss to the Holder. In the event that the
Corporation fails to direct its transfer agent to deliver the Common Stock to
the Holder within the time frame set forth in Section 5 and the Common Stock is
not delivered to the Holder by the Delivery Date, as compensation to the Holder
for such loss, the Corporation agrees to pay late payments to the Holder for
late issuance of the Common Stock in the form required pursuant to this Section
5 in the amount equal to $500 per business day after the Delivery Date. The
Corporation shall pay any payments incurred under this Section in immediately
available funds upon demand and, in the case of actual damages, accompanied by
reasonable documentation of the amount of such damages.

                  In the case of the exercise of the conversion rights set forth
in Section 5(a) the conversion privilege shall be deemed to have been exercised
and the shares of Common Stock issuable upon such conversion shall be deemed to
have been issued upon the date of receipt by the Corporation of the Notice of
Conversion. The person or entity entitled to receive Common Stock issuable upon
such conversion shall, on the date such conversion privilege is deemed to have
been exercised and thereafter, be treated for all purposes as the record holder
of such Common Stock and shall on the same date cease to be treated for any
purpose as the record holder of such shares of Series D Preferred Stock so
converted.

                  Upon the conversion of any shares of Series D Preferred Stock
no adjustment or payment shall be made with respect to such converted shares on
account of any dividend on the Common Stock, except that the holder of such
converted shares shall be entitled to be paid any dividends declared on shares
of Common Stock after conversion thereof.

                  The Corporation shall not be required, in connection with any
conversion of Series D Preferred Stock, and payment of dividends on Series D
Preferred Stock to issue a fraction of a share of its Series D Preferred Stock
and shall instead deliver a stock certificate representing the next whole
number.

                  In the event of any conversions of shares of Series D
Preferred Stock in part pursuant to this Section 5, such conversions shall be
deemed to constitute conversions of outstanding redemption amount applying to
Monthly Amounts (as defined in Section 10 below) for the Repayment Dates (as
defined in Section 10 below) in chronological order. By way of example, if the
original stated amount of the Series D Preferred Stock is $2,000,000 and the
Holder converted $300,000 of such original stated amount prior to the first
Repayment Date, then (1) the principal amount of the Monthly Amount due on the
first Repayment Date would equal $0, (2) the principal amount of the Monthly
Amount due on the second Repayment Date would equal $0 and (3) the principal
amount of the Monthly Amount due on the third Repayment Date would equal
$33,333.34, and (iv) the principal amount of the Monthly Amount due on each of
the remaining Repayment Dates would be $111,111.11 .

                  (d)      The Conversion Price determined pursuant to Section
5(b) shall be subject to adjustment from time to time as follows:

                           (i)      In case the Corporation shall at any time
(A) declare any dividend or distribution on its Common Stock or other securities
of the Corporation other than the Series A, B, or C Preferred Stock, (B) split
or subdivide the outstanding Common Stock, (C) combine the outstanding Common

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Stock into a smaller number of shares, or (D) issue by reclassification of its
Common Stock any shares or other securities of the Corporation, then in each
such event the Conversion Price shall be adjusted proportionately so that the
holders of Series D Preferred Stock shall be entitled to receive the kind and
number of shares or other securities of the Corporation which such holders would
have owned or have been entitled to receive after the happening of any of the
events described above had such shares of Series D Preferred Stock been
converted immediately prior to the happening of such event (or any record date
with respect thereto). Such adjustment shall be made whenever any of the events
listed above shall occur. An adjustment made to the Conversion Price pursuant to
this Section 5(d)(i) shall become effective immediately after the effective date
of the event for the event.

                  (e)      (i) In case of any merger of the Corporation with or
into any other corporation (other than a merger in which the Corporation is the
surviving or continuing corporation and which does not result in any
reclassification, conversion, or change of the outstanding shares of Common
Stock) then unless the right to convert shares of Series D Preferred Stock shall
have terminated, as part of such merger lawful provision shall be made so that
holders of Series D Preferred Stock shall thereafter have the right to convert
each share of Series D Preferred Stock into the kind and amount of shares of
stock and/or other securities or property receivable upon such merger by a
holder of the number of shares of Common Stock into which such shares of Series
D Preferred Stock might have been convertible by the holder immediately prior to
such consolidation or merger. Such provision shall also provide for adjustments
that shall be as nearly equivalent as may be practicable to the adjustments
provided for in Section (d) of this Section 5. The foregoing provisions of this
Section 5(e) shall similarly apply to successive mergers.

                           (ii)     In case of any sale or conveyance to another
person or entity of the property of the Corporation as an entirety, or
substantially as an entirety, in connection with which shares or other
securities or cash or other property shall be issuable, distributable, payable,
or deliverable for outstanding shares of Common Stock, then, unless the right to
convert such shares shall have terminated, lawful provision shall be made so
that the holders of Series D Preferred Stock shall thereafter have the right to
convert each share of the Series D Preferred Stock into the kind and amount of
shares of stock or other securities or property that shall be issuable,
distributable, payable, or deliverable upon such sale or conveyance with respect
to each share of Common Stock immediately prior to such conveyance.

                  (f)      Whenever the number of shares to be issued upon
conversion of the Series D Preferred Stock is required to be adjusted as
provided in this Section 5, the Corporation shall forthwith compute the adjusted
number of shares to be so issued and prepare a certificate setting forth such
adjusted conversion amount and the facts upon which such adjustment is based;
and the Corporation shall mail to each holder of record of Series D Preferred
Stock notice of such adjusted conversion price.

                  (g)      In case at any time the Corporation shall propose:

                           (i)      to pay any dividend or distribution payable
in shares upon its Common Stock or make any distribution (other than cash
dividends) to the holders of its Common Stock; or

                           (ii)     to offer for subscription to the holders of
its Common Stock any additional shares of any class or any other rights; or

                           (iii)    any capital reorganization or
reclassification of its shares or the merger of the Corporation with another
corporation (other than a merger in which the Corporation is the surviving or

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continuing corporation and which does not result in any reclassification,
conversion, or change of the outstanding shares of Common Stock); or

                           (iv)     the voluntary dissolution, liquidation or
winding-up of the Corporation;

then, and in any one or more of said cases, the Corporation shall cause at least
fifteen (15) days prior notice of the date on which (A) the books of the
Corporation shall close or a record be taken for such stock dividend,
distribution, or subscription rights, or (B) such capital reorganization,
reclassification, merger, dissolution, liquidation or winding-up shall take
place, as the case may be, to be mailed to the Transfer Agent for the Series D
Preferred Stock and to the holders of record of the Series D Preferred Stock.

                  (h)      So long as any shares of Series D Preferred Stock
shall remain outstanding and the holders thereof shall have the right to convert
the same in accordance with provisions of this Section 5 the Corporation shall
at all times reserve from the authorized and unissued shares of its Common Stock
a sufficient number of shares to provide for such conversions.

                  (i)      Overall Limit on Common Stock Issuable. The number of
shares of Common Stock issuable by the Corporation and acquirable by the Holder
under all securities issued by the Company to the Holder, shall not exceed an
aggregate of 4,769,535shares, subject to appropriate adjustment for stock
splits, stock dividends, or other similar recapitalizations affecting the Common
Stock (the "MAXIMUM COMMON STOCK ISSUANCE"), unless the issuance of shares
hereunder in excess of the Maximum Common Stock Issuance shall first be approved
by the Corporation's shareholders provided, however, that any shares of Common
Stock issued to Holder upon conversion of convertible securities or upon
exercise of warrants and subsequently sold by the Holder shall be excluded from
the calculation of the aggregate Maximum Common Stock Issuance. If at any point
in time and from time to time the number of shares of Common Stock issued
pursuant to conversion of the Preferred Stock, together with the number of
shares of Common Stock that would then be issuable by the Corporation in the
event of the conversion or exercise of all other securities issued by the
Company, would exceed the Maximum Common Stock Issuance but for this Section,
the Corporation shall promptly call a shareholders meeting to obtain shareholder
approval for the issuance of the shares of Common Stock hereunder in excess of
the Maximum Common Stock Issuance if required by the NASDAQ SmallCap listing
requirements.

                  (j)      The Corporation shall pay the amount of any and all
issue taxes (but not income taxes) which may be imposed in respect of any issue
or delivery of stock upon the conversion of any shares of Series D Preferred
Stock, but all transfer taxes and income taxes that may be payable in respect of
any change of ownership of Series D Preferred Stock or any rights represented
thereby or of stock receivable upon conversion thereof shall be paid by the
person or persons surrendering such stock for conversion.

                  (k)      Required Conversions. In the event that the volume
weighted average price (as determined using the AQR function on the Bloomberg
terminal) of the Corporation's Common Stock for all trades during any
consecutive eleven (11) day trading period on the Principal Market is at a price
greater than 118% of the Conversion Price, then the Corporation may, at its sole
option, provide the Holder irrevocable written notice ("CALL NOTICE") within
three (3) business days following such eleven (11) day period requiring the
conversion at the Conversion Price of all or a portion of the Stated Value held
by the Holder as of the date set forth in such Call Notice (the "CALL DATE"),
which such date shall be at least 11 trading days following the date of the Call
Notice, provided a registration statement covering resales of that number of
shares of Common Stock then issuable upon conversion of this Preferred Stock
pursuant to such Call Notice has been declared

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effective and is available for use. The amount of Common Stock to be issued in
connection with any such conversion pursuant to a particular Call Notice
pursuant to this Section 5(k) shall not exceed 25% of the aggregate dollar
trading volume of the Common Stock for the 11 trading days immediately preceding
the Call Date. If the volume weighted average price (as determined using the AQR
function on the Bloomberg terminal) of the Common Stock for all trades during
such consecutive eleven (11) day trading period preceding the Call Date falls
below 118% of the Conversion Price, then the Holder will no longer be required
to convert the Preferred Stock pursuant to such Call Notice.

         6.       Voting Rights. The shares of Series D Preferred Stock shall
not have voting rights.

         7.       Events of Default.

         The occurrence of any of the following events of default (each, an
"EVENT OF DEFAULT") shall, after the applicable period to cure the Event of
Default, cause the then applicable Dividend Rate described in Section 3 hereof
to become 20% from and after the occurrence of such event, and the Holder shall
have the option to require the Corporation to redeem the Series D Preferred
Stock held by such Holder by the immediate payment to the Holder by the
Corporation of a sum of money equal to 120% of the outstanding Stated Value,
plus accrued and unpaid dividends:

                  7.1      Failure to Make Payment. The Corporation fails to pay
any payment required to be paid pursuant to the terms of hereof or the failure
to timely pay any other sum of money due to the Holder from the Corporation and
such failure continues for a period of three (3) days after written notice to
the Corporation from the Holder.

                  7.2      Breach of Covenant. The Corporation breaches any
material covenant or other term or condition of this Certificate of Designations
or the Purchase Agreement in any material respect and such breach, if subject to
cure, continues for a period of five (5) days after written notice to the
Corporation from the Holder.

                  7.3      Breach of Representations and Warranties. Any
material representation or warranty of the Corporation made herein, in the
Purchase Agreement, or in any agreement, statement or certificate given in
writing pursuant hereto or in connection therewith shall have been false or
misleading when made.

                  7.4      Receiver or Trustee. The Corporation shall make an
assignment for the benefit of creditors, or apply for or consent to the
appointment of a receiver or trustee for it or for a substantial part of its
property or business; or such a receiver or trustee shall otherwise be
appointed.

                  7.5      Judgments. Except for judgments related to
obligations of JMAR Semiconductor, Inc., which are reflected on the
Corporation's balance sheet, any money judgment, writ or similar final process
shall be entered or filed against Corporation or any of its property or other
assets for more than $250,000, and shall remain unvacated, unbonded or unstayed
for a period of forty-five (45) days.

                  7.6      Bankruptcy. Bankruptcy, insolvency, reorganization or
liquidation proceedings or other proceedings or relief under any bankruptcy law
or any law for the relief of debtors shall be instituted by or against the
Corporation.

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                  7.7      Stop Trade. An SEC stop trade order or Principal
Market trading suspension.

                  7.8      Default Under Related Agreement. An Event of Default
occurs under and as defined in any one or more of the following agreements which
is not cured during any applicable cure or grace period: (i) Purchase and
Security Agreement dated March 21, 2003 between the Corporation, certain of its
subsidiaries, and Laurus Master Fund, Ltd., (ii) Securities Purchase Agreement
dated March 14, 2003 between the Corporation and Laurus Master Fund, Ltd., (iii)
Stock Pledge Agreement dated March 14, 2003 between the Corporation and Laurus
Master Fund, Ltd. and (iv) Pledge and Security Agreement dated March 14, 2003
between the Corporation and Laurus Master Fund, Ltd., as each such agreement may
be amended, modified and supplemented from time to time.

         8.       Mandatory Redemption. In the event any shares of Series D
Preferred Stock are outstanding twenty four (24) months from the date of
issuance thereof, any remaining Stated Value of such shares shall be redeemed in
accordance with Section 4 hereof and such shares shall be cancelled.

         9.       Optional Redemption. The Corporation will have the option of
redeeming any outstanding amount of the Stated Value of the Preferred Stock
("OPTIONAL REDEMPTION") by paying to the holder 118% of such amount, together
with accrued but unpaid dividends thereon and any and all other sums due,
accrued or payable to the holder arising under this certificate or any other
document delivered herewith ("REDEMPTION AMOUNT") outstanding on the day notice
of redemption ("NOTICE OF REDEMPTION") is delivered to a holder ("REDEMPTION
DATE"). A Notice of Redemption may not be given in connection with any portion
of Preferred Stock for which a Notice of Conversion has been given by the holder
at any time before receipt of a Notice of Redemption or given pursuant to the
following sentence. The holder may elect within five (5) business days after
receipt of a Notice of Redemption to give the Corporation a Notice of Conversion
in connection with some or all of the amount which was the subject of the Notice
of Redemption. The Redemption Amount must be paid in good funds to the holder no
later than the seventh (7th) business day after the Redemption Date ("OPTIONAL
REDEMPTION PAYMENT DATE"). In the event the Corporation fails to pay the
Redemption Amount by the Optional Redemption Payment Date, then the Redemption
Notice will be null and void. A Notice of Redemption may be given by the
Corporation, provided no Event of Default shall have occurred or be continuing.

         10.      Amortization.

                  (a)      Monthly Payments. Subject to the terms of this
Section 10, the Corporation shall repay one-eighteenth of the original Stated
Value of the Series D Preferred Stock (to the extent such amount has not been
converted pursuant to Section 5 above), together with the dividend accrued to
date on such portion of the original Stated Value then due and payable
(collectively the "MONTHLY AMOUNT"), in accordance with Section 10(b) below, on
the first business day of each consecutive calendar month (each, a "REPAYMENT
DATE"), beginning on July 1, 2004.

                  (b)      Cash or Common Stock. Subject to the terms hereof,
the Corporation has the sole option to determine whether to satisfy payment of
the Monthly Amount in full on each Repayment Date either in cash or in
registered shares of Common Stock, or a combination of both. The Corporation
shall deliver to the Holder a written irrevocable notice in the form of Exhibit
B attached hereto electing to pay such Monthly Amount in full on such Repayment
Date in either cash or registered Common Stock, or a combination of both
("REPAYMENT ELECTION NOTICE"). Such Repayment Election Notice shall be delivered
to the Holder at least ten (10) days prior to the applicable Repayment Date (the
date of such notice being hereinafter referred to as the

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"NOTICE DATE"). If such Repayment Election Notice is not delivered within the
prescribed period set forth in the preceding sentence, then the repayment shall
be made in either cash or shares of Common Stock on the same terms hereunder at
the Holder's sole option. If the Corporation elects or is required to repay all
or a portion of the Monthly Amount in cash on a Repayment Date, then on such
Repayment Date the Corporation shall pay to the Holder an amount equal to 102%
of the Monthly Amount in satisfaction of such obligation. If the Corporation
repays all or a portion of the Monthly Amount in shares of Common Stock, the
number of such shares to be issued for such Repayment Date shall be the number
determined by dividing (x) the portion of the Monthly Amount to be paid in
shares of Common Stock, by (y) the Conversion Price (as defined herein) as of
such date.

                  (c)      No Effective Registration. Notwithstanding anything
to the contrary herein, the Corporation shall be prohibited from exercising its
right to repay the Monthly Amount in shares of Common Stock (and must deliver
cash in respect thereof) on the applicable Repayment Date if at any time from
the Notice Date until the time at which the Holder receive such shares there
fails to exist an effective registration statement or an Event of Default
hereunder exists or occurs, unless otherwise waived in writing by the Holder in
whole or in part at the Holder's option.

                  (d)      Share Price/Issuance Limitations. Notwithstanding
anything to the contrary herein, if the closing price of the Common Stock as
reported by Bloomberg, L.P. on the Principal Market for any of the 11 trading
days preceding a Repayment Date was less than 118% of the Conversion Price, and
the Corporation has elected to pay all or a portion of the Monthly Amount in
shares of Common Stock, then, in lieu of the Corporation delivering the required
number of shares of Common Stock on the Repayment Date, Corporation shall pay
the Monthly Amount, or the unconverted part thereof, in cash.

                  (e) Deemed Conversions. Any repayment of the Monthly Amount in
shares of Common Stock pursuant to the terms hereof shall constitute and be
deemed a conversion of such portion of the applicable Stated Value of the Series
D Preferred Stock for all purposes under this Certificate and the Purchase
Agreement (as defined herein) (except as otherwise provided herein).

                  (f)      Deemed Ownership. In the case of the exercise of the
conversion rights or payment of the Monthly Amount set forth herein the
conversion privilege shall be deemed to have been exercised and the shares of
Common Stock issuable upon such conversion or Repayment shall be deemed to have
been issued upon the date of receipt by the Corporationof the Notice of
Conversion or on the Repayment Date if the Monthly Amount is paid in shares of
Common Stock, as the case may be. The person or entity entitled to receive
Common Stock issuable upon such conversion shall, on the date such conversion
privilege is deemed to have been exercised and thereafter, be treated for all
purposes as the record holder of such Common Stock.

         11.      Status of Converted or Redeemed Stock. In case any shares of
Series D Preferred Stock shall be redeemed or otherwise repurchased or
reacquired, the shares so redeemed, converted, or reacquired shall resume the
status of authorized but unissued shares of Preferred Stock and shall no longer
be designated as Series D Preferred Stock.

         In witness whereof, JMAR Technologies, Inc. has caused this Certificate
to be executed by Joseph G. Martinez, its Senior Vice President and General
Counsel, this 17th day of December, 2003.

                           JMAR TECHNOLOGIES, INC.

                           By: /s/ JOSEPH G. MARTINEZ

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<PAGE>

                                    EXHIBIT A

                              NOTICE OF CONVERSION

(To Be Executed By the Registered Holder in Order to Convert the Series D
Convertible Preferred Stock of JMAR Technologies, Inc.)

         The undersigned hereby irrevocably elects to convert ______________
shares of Series D Convertible Preferred Stock and $_____________ of the
dividend due, into shares of Common Stock of JMAR Technologies, Inc. (the
"Corporation") according to the conditions hereof, as of the date written below.

Date of Conversion:_____________________________________________________________

Applicable Conversion Price Per Share:__________________________________________

Number of Common Shares Issuable Upon This Conversion:__________________________

Signature:______________________________________________________________________

Print Name:_____________________________________________________________________

Address:________________________________________________________________________

________________________________________________________________________________

Deliveries Pursuant to this Notice of Conversion Should Be Made to:

________________________________________________________________________________

________________________________________________________________________________

________________________________________________________________________________

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