6th Amendment to Purchase and Sale


    Exhibit
      10.8.6

     

                SIXTH
      AMENDMENT
      TO

                PURCHASE
      AND SALE
      AGREEMENT

                AND
      PRELIMINARY
      ESCROW INSTRUCTIONS

    [Portion
      of DiCon Fiberoptics Inc. Land, Regatta Boulevard, Richmond,
      California]

    


    This
      Sixth Amendment to Purchase and Sale Agreement and Preliminary Escrow
      Instructions (the "Sixth
      Amendment") is
      entered into as of December 14, 2005, between DICON FIBEROPTICS, INC., a
      California corporation ("Seller") and
      PULTE
      HOME CORPORATION, a Michigan corporation ("Buyer").

    RECITALS

    


    
      	A.  	
              Seller
                and Buyer entered into a Purchase and Sale Agreement and Preliminary
                Escrow Instructions as of February 27, 2004, a First Amendment to
                Purchase
                and Sale Agreement and Preliminary Escrow Instructions as of March
                1,
                2004, a Second Amendment to Purchase and Sale Agreement and Preliminary
                Escrow Instructions as of April 29, 2004, a Third Amendment to Purchase
                and Sale Agreement and Preliminary Escrow Instructions as of February
                27,
                2005, a Fourth Amendment to Purchase and Sale Agreement and Preliminary
                Escrow Instructions as of July 27, 2005, and a Fifth Amendment to
                Purchase
                and Sale Agreement and Preliminary Escrow Instructions as of November
                17,
                2005 (collectively, the "Agreement").

            


    

    


    
      	B.  	
              Seller
                and Buyer desire to amend and restate certain provisions of the Agreement
                as provided in this Sixth
                Amendment.

            


    

    


    The
      parties agree as follows:

     

                                    AGREEMENT

    


    
      	1.  	
              Section
                8.1 of the Agreement is hereby amended by inserting the words "and
                live
                work" on line two thereof after the word "detached" and before the
                word
                "homes".

            


    

    


    
      	2.  	
              Section
                10.2 of the Agreement is hereby amended and restated in its entirety
                to
                read as follows:

            


    

    


    "10.2 Buyer's
      Covenants.

    


    
      	10.2.1  	
              Utilities.
                Within twelve (12) months after the Close of Escrow Buyer, at Buyer's
                cost
                and expense (including any fees) and subject to the approval of Seller,
                shall complete the design and engineering work and the construction
                work
                for the separation and the relocation of all utility services and
                all fire
                lines and fire lanes serving the Remaining Property and running over,
                under or across the Purchase Property, including the granting of
                new
                utility easements benefiting the Remaining Property and running over,
                under and across the Purchase Property and the installation of a
                new fire
                hydrant on the southeast corner of the Remaining Property. All deposits
                for utilities made by Seller and all refunds due from utilities shall
                be
                the property of Seller. Buyer shall be responsible for any required
                replacement of deposits. Seller shall release old utility easements
                that
                have been replaced by new utility easements pursuant to this Section
                10.2.1 after the completion of the construction work on the utility
                services using such new utility
                easements.

            


    

    


    
      	10.2.2  	
              Sanitary
                Sewer.
                Within twelve (12) months after the Close of Escrow Buyer, at Buyer's
                cost
                and expense (including any fees) and subject to the approval of Seller
                and
                with the cooperation of Seller, shall cause the City to accept
                responsibility for the construction, maintenance, repair and replacement
                of the existing sanitary sewers lying within the 10' private sanitary
                sewer easement and the 10' sanitary sewer easement, running from
                the
                boundary line of the Purchase Property and the Remaining Property
                along
                the southern boundary of the Purchase Property to Marina Bay Parkway
                and
                as shown on Parcel Map MS 754-01 recorded on December 24, 2001 in
                Book 182
                of Maps at pages 38-41, Contra Costa County Official Records and
                on the
                Acceptable Parcel Map, and the connection between the
                sewers.

            


    

    


    
      	10.2.3  	
              Fence.
                Within ten (10) days after the Close of Escrow Buyer, at Buyer's
                cost and
                expense (including any fees) and subject to the approval of Seller,
                shall
                install a temporary chain link fence separating the Purchase Property
                and
                the Remaining Property.

            


    

    


    
      	10.2.4  	
              New
                Parking Area.
                Within twelve (12) months after the Close of Escrow, for the areas
                to be
                designated by Seller on Lot 2, Buyer, at Buyer's cost and expense
                (including any fees) and subject to the approval of Seller, shall
                complete
                the design and engineering work and the construction work for new
                parking
                areas of not less than the greater of (i) three hundred (300) parking
                spaces or (ii) the number of parking spaces required by the City.
                The work
                for the new parking areas shall include, grading, paving, stripping
                parking spaces, landscaping, lighting, irrigation lines, fire lines,
                and
                fire lanes.

            


    

    


    
      	10.2.5  	
              Transformer;
                Utilities.
                Buyer shall not, and shall not permit any contractor or subcontractor
                or
                any other person to (a) use any electrical service from the existing
                transformer serving the Property, or (b) interfere with any utility
                service accessing the Remaining Property through the Purchase
                Property.

            


    

    


    
      	10.2.6  	
              Grading.
                Buyer shall not change the grade of the Purchase Property to a grade
                that
                will adversely affect the use of, or the storm water drainage to
                or from,
                the Remaining Property.

            


    

    


    
      	10.2.7  	
              Submission
                of Plans.
                Buyer shall submit the plans and specifications for the design and
                engineering work required under this Section 10.2 to Seller at least
                ten
                (10) Business Days prior to the commencement of the work pursuant
                to such
                plans and specifications so that Seller may inform Buyer whether
                the
                design and engineering work meets with Seller¡¦s
                approval.

            


    

    


    
      	10.2.8  	
              "As
                Built" Plans.
                Buyer shall furnish Seller with two hard copies and one soft copy
                of the
                "as built" plans and specifications for the work performed pursuant
                to
                this Section 10.2 as soon as such work is
                completed.

            


    

    


    
      	10.2.9  	
              Governmental
                Approvals.
                Buyer, at Buyer's cost and expense (including any fees), shall obtain
                in a
                timely manner all governmental approvals required in connection with
                the
                work contemplated by this Section 10.2. Buyer shall deliver to Seller
                the
                original or a copy of each such approval as soon as obtained by
                Buyer.

            


    

    


    
      	10.2.10  	
              Notice
                of Completion.
                With respect to any contract made by Buyer for the work to be performed
                under this Section 10.2, after completion of such work under such
                contract, Buyer shall execute and record, in the official records
                of the
                County of Contra Costa, a Notice of Completion meeting the requirements
                of
                California Civil Code Section 3093.

            


    

    


    
      	10.2.11  	
              Insurance.
                Buyer shall purchase and maintain insurance protecting Seller from
                claims
                which may arise out of or result from the work performed in connection
                with this Section 10.2, including liability, property damage and
                workmen¡¦s compensation. All such insurance shall name Seller as insured
                or additional insured, shall be issued by an insurer or insurers
                satisfactory to Seller, shall be written for not less than the limits
                of
                liability specified on Exhibit G hereto, and shall be otherwise
                satisfactory to Seller.

            


    

    


    Certificates
      of the insurance policies required under this Section 10.2.11 shall be delivered
      to Seller not less than thirty five (30 5)
/s/ SK /s/ HSL days prior to the commencement
      of the work to be performed
      under this Section 10.2."

    


    
      	3.  	
              Section
                11.1 of the Agreement is hereby amended by adding "SECTION 8," on
                lines
                three and ten thereof after "OBLIGATIONS UNDER" and before "SECTION
                10.2".

            


    

     

    Seller's
      Initials  /s/ HSL             
      Buyer's Initials /s/ SK


    
      	4.  	
              Section
                11.2 of the Agreement is hereby amended by adding "SECTION 8," on
                line two
                thereof after "OBLIGATIONS UNDER" and before "SECTION
                10.2".

            


    

    


    Seller's
      Initials  /s/ HSL 
Buyer's
      Initials /s/ SK

    


    
      	5.  	
              Except
                as amended and restated by this Sixth Amendment, all terms, conditions
                and
                provisions of the Agreement shall remain in full force and
                effect.

            


    

    


    
      	6.  	
              This
                Sixth Amendment may be executed by the different parties hereto on
                separate counterparts each of which, when so executed, shall be deemed
                an
                original but all such counterparts shall constitute but one and the
                same
                agreement.

            


    


    
      
        
        

      

      
        1

        
          

        

      

      
        
        

      

    


    IN
      WITNESS HEREOF, the
      parties hereto have executed this Sixth Amendment as of the date first above
      written.

    


    Seller:                                   
      Buyer:

    


    DICON
      FIBEROPTICS, INC.,                       
PULTE
      HOME
      CORPORATION

    a
      California corporation                    
      a
      Michigan corporation

    


    


    By:
      /s/ Ho-Shang
      Lee                     
                                                                                
      By: /s/ J. Steven
      Kalmbach       

    


    Name:
       Ho-Shang
      Lee, Ph.D.              Name:
       J.
      Steven
      Kalmbach

    Its: President
      and
      CEO                                              
              
      Its: Division
      President

     

                                Acceptance
      by Escrow
      Holder

    


    CHICAGO
      TITLE COMPANY hereby acknowledges that it has received originally executed
      counterparts or a fully executed original of the foregoing Sixth Amendment
      to
      Purchase and Sale Agreement and Preliminary Escrow Instructions and agrees
      to
      act as Escrow Agent thereunder and to be bound by and perform the terms thereof
      as such terms apply to Escrow Agent.

    


    CHICAGO
      TITLE COMPANY 

    


    By: _______________________________      

    


    Name:
       Laurie
      J.
      Edwards

    Its: Assistant
      Vice President

    Date
      of
      Execution: ____________________    

    



    
      
        
        

      

      
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    EXHIBIT
      G

    


    INSURANCE

    Liability       $5,000,000

    


    Property
      damage     $5,000,000

    


    Workers'
      compensation  $2,000,000

    


    Employer's
      practice liability   $1,000,000