SECURITY AGREEMENT

THIS IS A SECURITY AGREEMENT  made this 10th day of July, 1997 by and between


VISION CAPITAL GROUP, LLC
a Delaware limited liability company with an office at
1266 Main Street
Stamford, Connecticut 06902                                          ("Lender")

INTELLIGENT DECISION SYSTEMS, INC.
a Delaware corporation
with an office at
88 Danbury Road
Wilton, Connecticut 06897                                          ("Borrower")


                                   WITNESSETH:


         WHEREAS,  Borrower is this date entering into a letter  agreement  with
Lender (the  "Agreement")  pursuant to which,  among other things,  Borrower has
agreed to make  certain  payments to Lender  and,  to  evidence  certain of such
payments,  is  issuing  to  Lender  Borrower's  Secured  Promissory  Note in the
principal amount of $406,764 (the "Note");

         WHEREAS,  as an  inducement  to Lender to accept the  Agreement and the
Note  (collectively  the "Payment  Documents"),  Borrower has agreed to grant to
Lender  a  security  interest  and lien  upon the  assets  of  Borrower  and its
subsidiaries  who are or are  required to become  signatories  to this  Security
Agreement (collectively with Borrower,  jointly and severally the "Debtor"), all
as herein provided.

         NOW, THEREFORE, THE PARTIES HERETO DO HEREBY AGREE AS FOLLOWS:

         Section 1.        Security Interests; Subordination.

                  1.1      Creation of Security Interest.

         As security  for the  payments  due from  Borrower to Lender  under the
Payment  Documents and the performance by Borrower of its obligations under this
Agreement  the Debtor  hereby gives and grants to Lender a security  interest in
the collateral  described herein. The Collateral includes all accounts,  account
and lease receivable,  leases,  sales contracts and other agreements calling for
the lease or sale of Vision  and/or  Focus  Equipment  (as defined on Schedule A
hereto),  all  rights to  receive  payment  under any of the  foregoing  and all
instruments,  notes,  chattel  paper and other  evidences  of  payment  relating
thereto now existing or  hereafter  entered into or acquired by any of Borrower,
Digital Sciences,  Inc.,  Neptune Technology Leasing Corp. and/or any present or
future  subsidiaries  of any of the foregoing and all Vision and Focus Equipment
underlying or the subject of any of the foregoing. Lender agrees and


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acknowledges  that its interest in the  Collateral  is  subordinate  to existing
senior liens payable in full out of rentals under leases constituting Collateral
and to the right of "quiet  enjoyment"  on the part of lessees and  customers of
Vision and/or Focus Equipment.

         1.2      Subordination.

         In the event that Borrower,  in the ordinary course of its business for
purposes  of raising  funds to operate  and/or  expand  its  business  and/or to
purchase or otherwise acquire additional assets and/or other business (including
by merger,  stock or asset  acquisition or otherwise),  determines  from time to
time  to  raise  such  funds  through  a  third  party  financing   requiring  a
subordination  of Lender's  security  interest in any of the Collateral,  Lender
agrees,  upon  reasonable  notice thereof  (including a description of the terms
thereof and a copy of the  documentation  evidencing same) from such third party
financing source,  to subordinate its security interest  hereunder to such third
party  financing  lien so long as the  terms  of such  financing  are  fair  and
reasonable and consistent with industry practice.

         The foregoing  subordination  obligations and provisions  shall include
and  apply to  financing  transaction(s)  hereinafter  entered  into,  with,  or
arranged by Mid America Venture Capital Fund and/or its affiliates.

         Section 2.        Representations and Warranties and Covenants.

         Borrower  represents  and  warrants to Lender as of the date  hereafter
that:

         2.1      Organization, Charter, Laws and Capitalization.

         (A)      Borrower is a duly organized and validly existing  corporation
under the laws of the State of Delaware;

and

         (B) The  execution,  delivery and  performance  of this  Agreement  are
within each Debtor's  corporate  powers,  have been duly authorized,  are not in
contravention  of any law or any terms of any  Debtor's  charter  or  by-laws or
other  incorporation  papers or any agreement or undertaking to which any Debtor
is a party.


         2.2      Payments.

         Borrower shall pay punctually any and all of the payments, when due, as
required by the terms of the Payment Documents.

         2.3      Preservation of Collateral.

         Borrower shall, and shall cause each other Debtor (as applicable), to:

         (A)      Preserve the Collateral in good condition and order  (ordinary
wear and tear excepted) and not permit it to be abused or misused;





<PAGE>



         (B) Perfect a security interest (using a method satisfactory to Lender)
in goods covered by any instrument, document or chattel paper in the Collateral.

         (C) Execute and agree to be bound by the terms and  provisions  of this
Security Agreement.


         Section 3.        Events of Default - Acceleration.

         The Note shall,  at the sole option of Lender,  be immediately  due and
payable,  without notice or demand, upon the occurrence of any of the following,
(hereinafter, "Events of Default"): Default in the payment, when due or payable,
of any  installments  or other  amounts due under the Payment  Documents,  which
default continues for a period of ten (10) days.

         Section 4.        Remedies on Default: Provision re Collateral, Etc.

         If an Event of Default shall have  occurred,  Lender may accelerate and
declare to be  immediately  due and  payable all  obligations  under the Payment
Documents  and may  proceed to protect and enforce its rights by suit in equity,
action  at law or  other  appropriate  proceedings,  whether  for  the  specific
performance of any agreement contained therein or in any other document,  or for
an injunction  against a violation of any of the terms hereof or thereof,  or in
aid of the exercise of any right, power or remedy granted thereby law, equity or
otherwise.

         Without  limitation  of any rights and remedies of Lender as a security
party under the  Uniform  Commercial  Code and any rights or remedies  set forth
herein or in any other document,  if an Event of Default shall exist  hereunder,
Lender shall have all of the  following  rights and remedies with respect to the
Collateral or any portion thereof:

                  (i) Lender may at any time and from time to time with judicial
process where legally  required and the aid or assistance of others,  enter upon
any  premises  in  which  any of the  Collateral  may be  located  and,  without
resistance or  interference  by any Debtor,  take  possession of the  Collateral
and/or dispose of any part of all of the Collateral on any such premises; and/or
require  Debtor to  assemble  and make  available  to Lender,  at the expense of
Borrower,  any part or all of the Collateral at any place or time  designated by
Lender  which is  convenient  to  Lender,  and/or  remove any part or all of the
Collateral from any premises on which any part may be located for the purpose of
effecting sale or other disposition thereof,  and/or sell, resell, lease, assign
and  deliver,  grant  option  for  or  otherwise  dispose  of  any or all of the
Collateral  in its then  condition  or  following  any  commercially  reasonable
preparation  or processing at public or private sale or  proceedings,  by one or
more contracts,  in one or more parcels, at the same or different times, with or
without  having the  Collateral at the place of sale or other  disposition,  for
cash and/or credit, and upon any terms, at such place(s) and time(s) and to such
persons as Lender shall deem best,  all without  demand for  performance  or any
notice or  advertisement  whatsoever,  except that unless any of the  Collateral
shall be  perishable  or is of a type that can decline  speedily  in value,  the
Debtor  shall be given five  business  days' notice of the place and time of any
public  sale or of the time  after  which  any  private  sale or other  intended
disposition is to be made,  which notice  Borrower hereby agrees shall be deemed
reasonable  notice  thereof.  If any of the  Collateral  is sold by Lender  upon
credit or for future delivery, Lender shall not be liable for the failure of the
purchaser to pay for same and in such





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event Lender may resell such  Collateral.  Lender may buy any part or all of the
Collateral  at any public sale and if any part or all of the  Collateral is of a
type customarily sold in a recognized  market or is of the type which is subject
of widely  distribute  standard price quotations  Lender may buy at private sale
and may make  payment  therefor by  application  of all or a part of the Payment
Documents;

                  (ii)  Lender  may,  in  Lender's  discretion,  apply  the cash
proceeds from any sale or other  disposition of the  Collateral,  first,  to the
reasonable expenses of retaking,  holding,  preparing for sale, selling, leasing
and otherwise disposing of such Collateral, to reasonable appraisal,  accounting
and attorneys' fees and all legal expenses,  travel and other expenses which are
to be paid or  reimbursed  to Lender,  pursuant  hereto or pursuant to any other
document,  (provided,  however,  that Lender may not apply said proceeds against
any such costs and  expenses  incurred by Lender  during the first  fifteen days
after  the  Event  of  Default  giving  rise  thereto)  second,  to all  accrued
interests,  fees and charges outstanding with respect to the Note in such order,
as Lender  shall  determine,  third,  any surplus to any other  secured  parties
having an interest in the  Collateral  known to Lender in accordance  with their
interests,  and  fourth,  any  surplus  to the  Debtor or other  party  entitled
thereto;  provided,  however,  that Borrower shall remain liable with respect to
unpaid  portions  of the  Payment  Documents  and will pay  Lender on demand any
deficiency remaining together with interest thereon.  Notwithstanding any of the
foregoing,  Lender shall have no liability to marshall assets for the benefit of
any other  creditor,  or be  subject  to any  restrictions  with  respect to the
liquidation or other disposal of the Collateral.

                  (iii)  Effective  upon an Event  of  Default,  subject  to the
rights and prior  approval  (which  shall not be  unreasonably  withheld) of any
third  party  financing  source to whom  Lender  has become  subordinated  under
Section 1.2  hereof,  Lender is hereby  granted by each  Debtor the  irrevocable
right  and  interest  to  collect  and  receive  proceeds  and  revenues  of the
Collateral,  to endorse such  Debtor's name on any checks,  notes,  acceptances,
money  orders,  drafts or other forms of payment or security with respect to the
Collateral;  to sign such Debtor's name on an invoice or bill of lading or other
document  relating to the  Collateral,  and on notices of assignment,  financing
statements  and  other  public  records;  to do any act  which  such  Debtor  is
obligated to do under the terms and  conditions of this  Agreement;  to exercise
such rights as such Debtor might  exercise and to do all other things  necessary
to enforce and carry out Lender's rights and remedies under this Agreement.

During the term of the Note,  each Debtor  shall give Lender  periodic  (no less
often than monthly) reports of all leases, sales agreements and other agreements
constituting  Collateral hereunder.  Such reports shall include the identify and
address of each  lessee,  buyer or other  party  thereto,  the  description  and
location of all Equipment  covered thereby and the payment terms under each such
agreement.

         Section 5.        Cumulative Remedies: No waivers, Etc.

         No right,  power or remedy  granted  to  Lender  in this  Agreement  is
intended to be exclusive,  but each shall be  cumulative  and in addition to any
other  rights,  power or remedies  referred to in this  Agreement  or  otherwise
available  to Lender at law or in  equity;  and the  exercise  or  beginning  of
exercise by Lender of any one or more of such rights, powers or remedies,  shall
not preclude  the  simultaneous  or later  exercise by Lender of any or all such
other rights,  powers or remedies. No waiver by, nor any failure or delay on the
part of Lender in any one or more instances to insist upon strict performance or
observance of one or more covenants or conditions hereof shall in any way be, or
be  construed  to be, a waiver of such  covenants  in any other  instance  or to
prevent Lender's rights to later require the strict


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performance  or  observance  of  such  covenants  or  conditions,  or  otherwise
prejudice Lender's rights, power or remedies.

         Section 6.        Partial Invalidity: Waivers.

         6.1 If any  term or  provision  of this  agreement  or the  application
thereof  to any  person or  circumstance  shall,  to any  extent,  be invalid or
unenforceable  by reason of any applicable law, the remainder of this Agreement,
or application of such term or provision to persons or circumstances  other than
those as to which it is held  invalid or  unenforceable,  shall not be  affected
thereby,  and each term and  provision of this  Agreement  shall be valid and be
enforced to the fullest  extent  permitted by law. To the full extent,  however,
that the provisions of any such  applicable  law may be waived,  they are hereby
waived by Borrower.

         6.2 To the extent  permitted by applicable law,  Borrower hereby waives
protest, notice of default or dishonor,  notice of payments and nonpayments,  or
of any default.

         Section 7.     Further Assurances Possession of Collateral: Custodians.

         Borrower will deliver,  and will cause each other Debtor to deliver, to
Lender  such  financing   statements  and  other  instruments   constituting  or
evidencing  items of the  Collateral,  as may be requested by Lender,  to better
assure it with respect to the security  interests granted to it pursuant to this
Agreement.  Borrower  will  execute  and  deliver,  and cause to be  executed an
delivered,  such other and further  instruments and/or documents as Lender shall
require to implement and carry out the transaction described herein.

         Section 8.        Failure to Perform.

         If  Borrower  shall fail to observe  or  perform  any of the  covenants
hereof,  Lender  may pay  amounts or incur  liabilities  to remedy or attempt to
remedy any such  failure and all such  payments  made and  liabilities  incurred
shall be for the account of  Borrower,  and  consequently,  and all such amounts
shall be repaid by Borrower on demand.  The  provisions  of this Section and any
such  action by Lender  shall not  prevent  any  default  in the  observance  or
performance of any covenant hereof constituting an Event of Default hereunder.

         Section 9.        Notices, Etc.

         All  notices,  requests,  consents and other  communications  hereunder
shall be in writing and shall be deemed to be duly delivered if mailed,  postage
prepaid, by first class registered mail, return requested,  or by any nationally
recognized  receipted delivery or courier service,  to the respective address of
the parties set forth at the head of this  Agreement or at such other address as
may have been furnished by either party to the other.

         Section 10.       Amendments and Waivers.

         This  Agreement may not be changed,  waived,  discharged or terminated,
except by writing signed by the party to be charged.


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         Section 11.       Miscellaneous.

         11.1 This  Agreement  shall be deemed a security  agreement  within the
meaning of the  Connecticut  Uniform  Commercial  Code.  This Agreement shall be
construed and enforced in accordance  with and governed by the laws of the State
of  Connecticut.  Borrower and Lender hereby consent to the  jurisdiction of the
courts  of the  State of  Connecticut  and to be bound by the  decisions  of the
courts of the State of Connecticut.  All of the terms of this Agreement shall be
binding  upon and inure to the  benefit  of and be  enforced  by the  respective
successors and assigns of the parties  hereto,  whether so expressed or not, and
other holder or holders at the time of the Note.  The headings in this Agreement
are for the purpose of reference  only and shall not limit or  otherwise  affect
any  of  the  terms  hereof.  This  Agreement  may be  executed  in two or  more
counterparts,  each of which  shall be deemed an  original,  and by the  several
partied  hereto  in  separate  counterparts,  but all of  which  together  shall
constitute one and the same instrument.

         11.2  This  Agreement  shall not be  relied  upon by any  third  party.
Without  limiting  the  foregoing,  Lender  shall have no liability to any party
whatever (including,  without limitation,  Borrower,  any other Debtor or anyone
conducting  business with any of the  foregoing)  in the event  Lender,  for any
reason and at any time, exercise its rights under this Agreement.

         Section 12.       Release.

         Upon full payment and  satisfaction  of the Payment  Documents and upon
termination   of  this  Agreement  by  Lender,   the  parties  shall   thereupon
automatically each be fully,  finally,  and forever released and discharged from
any further claim,  liability or obligation in connection  with the payments due
thereunder. Notwithstanding the foregoing, in the event any payment is recovered
from Lender in whole or in part, as a result of any  insolvency  proceedings  or
otherwise,  the rights,  benefits  and  security  interests of Lender under this
Agreement  shall  remain  in full  force  and  effect  as to any and all of such
recovered sums.

         IN  WITNESS  WHEREOF,  each of the  parties  hereto has  executed  this
Agreement on the day first above mentioned.

INTELLIGENT DECISION SYSTEMS, INC.(Debtor)   DIGITAL SCIENCES, INC.(Debtor)

BY:  /s/  David Horowitz                     BY:  /s/  David Horowitz
    ---------------------------------           -----------------------------
ITS:  Chairman                              ITS:  President
    ---------------------------------           -----------------------------

VISION CAPITAL GROUP, LLC                      NEPTUNE TECHNOLOGY LEASING, CORP.
                                               (Debtor)

BY:  /s/  Stephen M. Chaleff                 BY:  /s/ Jonathan Preiser
    ---------------------------------            ----------------------------
ITS:  Member                                ITS:  Vice President
    ---------------------------------            ----------------------------




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                                   SCHEDULE A



                  Vision  and  focus  systems  as  currently   manufactured  and
                  marketed by IDSI and  subsidiaries and third parties using the
                  nomenclature  "Vision" and "Focus" together with all upgrades,
                  modifications, enhancements and replacements hereafter created
                  whether or not called "Vision" and "Focus"