SECURITIES AND EXCHANGE COMMISSION

                     Washington, D.C. 20549

                          Schedule 13G


           Under the Securities Exchange Act of 1934
                      (Amendment No. 10)*


                  RICHARDSON ELECTRONICS LTD.
            _______________________________________
                        (Name of Issuer)


                          COMMON STOCK
            _______________________________________
                 (Title of Class of Securities)


                           763165107
            _______________________________________
                         (CUSIP Number)


Check the following box if a fee is being paid with this
statement.  (A fee is not required only if the filing person: (1)
has a previous statement on file reporting beneficial ownership
of more than five percent of the class of securities described in
Item 1; and (2) has filed no amendment subsequent thereto
reporting beneficial ownership of five percent or less of such
class.)  (See Rule 13d-7.)

*The remainder of this cover page shall be filled out for a
reporting person's initial filing on this form with respect to
the subject class of securities, and for any subsequent amendment
containing information which would alter the disclosures provided
in a prior cover page.

The information required in the remainder of this cover page
shall not be deemed to be "filed" for the purpose of Section 18
of the Securities Exchange Act of 1934 ("Act") or otherwise
subject to the liabilities of that section of the Act but shall
be subject to all other provisions of the Act (however, see the
Notes).

                (Continued on following page(s))

                       Page 1 of 8 Pages
CUSIP NO. 763165107             13G       Page 2 of 8 Pages

1  Name of Reporting Person
   S.S. or I.R.S. Identification No. of Above Person

   T. ROWE PRICE ASSOCIATES, INC.
   52-0556948

2  Check the Appropriate Box if a Member of a Group*

                                                       (a) ____
   NOT APPLICABLE                                      (b) ____

3  SEC Use Only

   ______________________________

4  Citizenship or Place of Organization

   MARYLAND

Number of      5  Sole Voting Power
               **
Shares            154,700

Beneficially   6  Shared Voting Power
               **
Owned By Each     NONE

Reporting      7  Sole Dispositive Power
               **
Person            1,452,266

With           8  Shared Dispositive Power

                  NONE

9  Aggregate Amount Beneficially Owned by Each Reporting Person

   1,452,266

10 Check Box if the Aggregate Amount in Row (9) Excludes Certain
   Shares*

   NOT APPLICABLE

11 Percent of Class Represented by Amount in Row 9

   9.7%

12 Type of Reporting Person*

   IA

              *SEE INSTRUCTION BEFORE FILLING OUT!
        **Any shares reported in Items 5 and 6 are also
                      reported in Item 7.
CUSIP NO. 763165107             13G       Page 3 of 8 Pages

1  Name of Reporting Person
   S.S. or I.R.S. Identification No. of Above Person

   T. Rowe Price Small-Cap Value Fund, Inc.
   52-1575325

2  Check the Appropriate Box if a Member of a Group*

                                                       (a) ____
   NOT APPLICABLE                                      (b) ____

3  SEC Use Only

   __________________________

4  Citizenship or Place of Organization

   MARYLAND

Number of      5  Sole Voting Power
               **
Shares            1,297,566

Beneficially   6  Shared Voting Power
               **
Owned By Each     NONE

Reporting      7  Sole Dispositive Power
               **
Person            NONE

With           8  Shared Dispositive Power

                  NONE

9  Aggregate Amount Beneficially Owned by Each Reporting Person

   1,297,566

10 Check Box if the Aggregate Amount in Row (9) Excludes Certain
   Shares*

   NOT APPLICABLE

11 Percent of Class Represented by Amount in Row 9

   8.7%

12 Type of Reporting Person*

   IV

              *SEE INSTRUCTION BEFORE FILLING OUT!
**The aggregate amount reported on this page is also included in
the aggregate amount reported by T. Rowe Price Associates, Inc.
on page 2 of this Schedule 13G.
SCHEDULE 13G
PAGE 4 OF 8

Item 1(a) Name of Issuer:

          Reference is made to page 1 of this Schedule 13G

Item 1(b) Address of Issuer's Principal Executive Offices:

          40W267 Keslinger Road, Lafox, Illinois 60147


Item 2(a) Name of Person(s) Filing:

          (1)  T. Rowe Price Associates, Inc. ("Price
               Associates")

          (2)  T. Rowe Price Small-Cap Value Fund, Inc.

  X       Attached as Exhibit A is a copy of an agreement between
          the Persons Filing (as specified hereinabove) that this
          Schedule 13G is being filed on behalf of each of them.

Item 2(b) Address of Principal Business Office:

          100 E. Pratt Street, Baltimore, Maryland 21202

Item 2(c) Citizenship or Place of Organization:

          (1)  Maryland

          (2)  Maryland

Item 2(d) Title of Class of Securities:

          Reference is made to page 1 of this Schedule 13G

Item 2(e) CUSIP Number: 763165107


Item 3    The person filing this Schedule 13G is an:

  X       Investment Adviser registered under Section 203 of the
          Investment Advisers Act of 1940

  X       Investment Company registered under Section 8 of the
Investment Company Act of 1940
CUSIP 763165107
PAGE 5 OF 8

Item 4    Ownership                           Deemed
                                           Outstanding
                                               And
                                           Beneficially
                              Units       Owned Directly
                              Deemed        Subject to
                           Beneficially     Warrants &
                              Owned         Conversion
                             Directly       Privileges    Total
                           ____________   ______________ _______

(1) WITH RESPECT TO
    PRICE ASSOCIATES
    (includes shares
    reported in
    (2) below):

    (a) Amount
        Beneficially
        Owned . . . . . .     891,100     561,166       1,452,266

    (b) Percent of
        Class . . . . . . . . . . . . . . . . . . . . . .    9.7%

    (c) Number of
        units as
        to which
        such
        person has: . . .  ___________    ___________      ______

       (i)  *sole power
            to vote or
            to direct
            the vote . . .     154,700         -0-        154,700

      (ii)  *shared power
            to vote or
            to direct
            the vote . . .      -0-            -0-           -0-

     (iii)  *sole power
            to dispose or
            to direct the
            disposition
            of . . . . .       891,100      561,166     1,452,266
            *shared power
            to dispose or
            to direct the
            disposition
            of . . . . .         -0-            -0-          -0-
(2) WITH RESPECT TO                          CUSIP 763165107
    T. Rowe Price Small-Cap Value            Page 6 of 8 Pages
            Fund, Inc.
                                              Deemed
                                           Outstanding
                                               And
                                           Beneficially
                              Units       Owned Directly
                              Deemed        Subject to
                           Beneficially     Warrants &
                              Owned         Conversion
                             Directly       Privileges    Total
                           ____________   ______________ _______


    (a) Amount
        Beneficially
        Owned . . . . . .       736,400     561,166     1,297,566

    (b) Percent of
        Class . . . . . . . . . . . . . . . . . . . . . .  8.7%

    (c) Number of
        units as
        to which
        such person
        has . . . . . . .  ___________    ___________      ______

       (i)  *sole power to
            vote or to
            direct the
            vote . . . .        736,400      561,166    1,297,566

      (ii)  *shared power
            to vote or
            to direct
            the vote . . .         -0-          -0-        -0-

     (iii)  *sole power
            to dispose or
            to direct the
            disposition
            of . . . . .           -0-          -0-        -0-
      (iv)  *shared power
            to dispose or
            to direct the
            disposition
            of . . . . .           -0-          -0-        -0-

*Units reported in subcategories (i) and (ii) are also included
in subcategory (iii) or (iv).
SCHEDULE 13G                              Page 7 of 8

Item 5 Ownership of Five Percent or Less of a Class.

  X    Not Applicable.

_____  This statement is being filed to report the fact that, as
       of the date of this report, the reporting person(s) has
       (have) ceased to be the beneficial owner of more than five
       percent of the class of securities.

Item 6 Ownership of More than Five Percent on Behalf of Another
       Person

       (1) Price Associates does not serve as custodian of the
           assets of any of its clients; accordingly, in each
           instance only the client or the client's custodian or
           trustee bank has the right to receive dividends paid
           with respect to, and proceeds from the sale of, such
           securities.

           The ultimate power to direct the receipt of dividends
           paid with respect to, and the proceeds from the sale
           of, such securities, is vested in the individual and
           institutional clients which Price Associates serves as
           investment adviser.  Any and all discretionary
           authority which has been delegated to Price Associates
           may be revoked in whole or in part at any time.

           Except as may be indicated if this is a joint filing
           with one of the registered investment companies
           sponsored by Price Associates which it also serves as
           investment adviser ("T. Rowe Price Funds"), not more
           than 5% of the class of such securities is owned by
           any one client subject to the investment advice of
           Price Associates.

       (2) With respect to securities owned by any one of the T.
           Rowe Price Funds, only State Street Bank and Trust
           Company, as custodian for each of such Funds, has the
           right to receive dividends paid with respect to, and
           proceeds from the sale of, such securities.  No other
           person is known to have such right, except that the
           shareholders of each such Fund participate
           proportionately in any dividends and distributions so
           paid.

Item 7 Identification and Classification of the Subsidiary Which
       Acquired the Security Being Reported on By the Parent
       Holding Company.

       Not Applicable.
Item 8 Identification and Classification of Members of the Group.

       Not Applicable.

SCHEDULE 13G
PAGE 8 OF 8

Item 9   Notice of Dissolution of Group.

         Not Applicable.

Item 10  Certification.

         By signing below I (we) certify that, to the best of my
         (our) knowledge and belief, the securities referred to
         above were acquired in the ordinary course of business
         and were not acquired for the purpose of and do not have
         the effect of changing or influencing the control of the
         issuer of such securities and were not acquired in
         connection with or as a participant in any transaction
         having such purpose or effect.  T. Rowe Price
         Associates, Inc. hereby declares and affirms that the
         filing of Schedule 13G shall not be construed as an
         admission that Price Associates is the beneficial owner
         of the securities referred to, which beneficial
         ownership is expressly denied.

                           Signature.

         After reasonable inquiry and to the best of my (our)
         knowledge and belief, I (we) certify that the
         information set forth in this statement is true,
         complete and correct.

Dated: February 14, 2006           Dated: February 14, 2006


T. ROWE PRICE SMALL-CAP            T. ROWE PRICE ASSOCIATES, INC.
   VALUE FUND, INC.



By:  /s/ Joseph A. Carrier         By:  /s/ Henry H. Hopkins
     Joseph A. Carrier,                 Henry H. Hopkins,
     Treasurer                          Vice President

Note:    This Schedule 13G, including all exhibits, must be filed
         with the Securities and Exchange Commission, and a copy
         hereof must be sent to the issuer by registered or
         certified mail not later than February 14th following
         the calendar year covered by the statement or within the
         time specified in Rule 13d-1(b)(2), if applicable.

12/31/2005
                                                  EXHIBIT A


                           AGREEMENT

                  JOINT FILING OF SCHEDULE 13G


     T. Rowe Price Associates, Inc. (an investment adviser
registered under the Investment Advisers Act of 1940) and T. Rowe
Price Small-Cap Value Fund, Inc., a Maryland corporation, hereby
agree to file jointly the statement on Schedule 13G to which this
Agreement is attached, and any amendments thereto which may be
deemed necessary, pursuant to Regulation 13D-G under the
Securities Exchange Act of 1934.

     It is understood and agreed that each of the parties hereto
is responsible for the timely filing of such statement and any
amendments thereto, and for the completeness and accuracy of the
information concerning such party contained therein, but such
party is not responsible for the completeness or accuracy of
information concerning the other party unless such party knows or
has reason to believe that such information is inaccurate.

     It is understood and agreed that a copy of this Agreement
shall be attached as an exhibit to the statement on Schedule 13G,
and any amendments hereto, filed on behalf of each of the parties
hereto.


Dated: February 14, 2006           Dated: February 14, 2006


T. ROWE PRICE SMALL-CAP            T. ROWE PRICE ASSOCIATES, INC.
   VALUE FUND, INC.



By:  /s/ Joseph A. Carrier         By:  /s/ Henry H. Hopkins
     Joseph A. Carrier,                 Henry H. Hopkins,
     Treasurer                          Vice President