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                                                                    Exhibit 5.01

   Corning Incorporated                               William D. Eggers
   One Riverfront Plaza                               Senior Vice President
   Corning, New York 14831                            and General Counsel
       607.974.5656
       607.974.8656 fax

                                                              August 23, 2000


To the Board of Directors
Corning Incorporated

Ladies and Gentlemen:

      As General Counsel of Corning Incorporated (the "Company"), I am
furnishing this opinion in connection with the Registration Statement (the
"Registration Statement") on Form S-3 being filed with the Securities and
Exchange Commission (the "Commission") under the Securities Act of 1933, as
amended, with respect to the proposed offering from time to time of up to
$4,000,000,000 aggregate amount of (i) the Company's debt securities (the "Debt
Securities"), (ii) shares of the Company's Preferred Stock, par value $100 per
share (the "Preferred Shares"), which may be represented by depositary shares
(the "Depositary Shares"), (iii) shares of the Company's Common Stock, par value
$.50 per share (the "Common Shares"); (iv) warrants to purchase Debt Securities,
Preferred Shares or Common Shares (the "Warrants"), (v) the guaranteed debt
securities ("Guaranteed Debt Securities") of Corning Finance B.V., an indirect
wholly-owned subsidiary of the Company, and (vi) the guarantee by the Company of
any Guaranteed Debt Securities issued by Corning Finance B.V. pursuant to a
Guarantee Agreement to be executed by the Company (the "Guarantees"). The
Warrants, the Debt Securities, the Preferred Shares, the Depositary Shares, the
Common Shares and the Guarantees are collectively referred to as the
"Securities." Any Debt Securities and Preferred Shares may be convertible into
or exchangeable for Common Shares or other Securities.

      The Debt Securities will be issued in one or more series pursuant to an
Indenture (the "Indenture") dated as of __________ between the Company and The
Chase Manhattan Bank (the "Trustee"), a form of which is filed as Exhibit 4.01
to the Registration Statement on Form S-3, Registration Nos. 333-81299 and
333-81299-01. The Guaranteed Debt Securities will be issued in one or more
series pursuant to an Indenture (the "B.V. Indenture") dated as of __________
among Corning Finance B. V., The Chase Manhattan Bank (the "Trustee") and
Corning Incorporated, a form of which is filed as Exhibit 4.02 to the
Registration Statement on Form S-3, Registration Nos. 333-81299 and
333-81299-01. The Warrants will be issued under one or more warrant agreements
(each, a "Warrant Agreement") to be entered into between the Company and a
financial institution identified therein as warrant agent (each, a "Warrant
Agent"). The Depositary Shares will be issued under one or more deposit
agreements (each, a "Deposit Agreement") to be entered into between the Company
and a financial institution identified therein as depositary (each, a
"Depositary").

      I have examined the resolutions of the Board of Directors of the Company
(the "Resolutions") authorizing the issuance, offering and sale of the
Securities. I have also examined the originals, or copies identified to my
satisfaction, of such corporate records of the Company and Corning Finance B.V.,
respectively; such other agreements and instruments, certificates of public
officials and officers of the Company and Corning Finance B.V. and other
persons; and such other documents as I have deemed necessary as a basis for the
opinions hereinafter expressed.

      Based on the foregoing, and having regard for such legal considerations as
I have deemed relevant, I am of the opinion that:

      1. The Indenture, when duly authorized, executed and delivered by the
Company, assuming due authorization, execution and delivery thereof by the
Trustee, will constitute a legally binding instrument of the Company enforceable
against the Company in accordance with its terms.
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      2. The B.V. Indenture, when duly authorized, executed and delivered by
Corning Finance B.V., assuming due authorization, execution and delivery thereof
by the Trustee, will constitute a legally binding instrument of Corning Finance
B.V. enforceable against Corning Finance B.V. in accordance with its terms.

      3. The Debt Securities (including Debt Securities issuable upon conversion
of or exchange for any Security or upon exercise of any Warrant) have been duly
authorized and, when the final terms thereof have been duly established and
approved, when duly executed by the Company, in each case pursuant to the
authority granted in the Resolutions, when executed and authenticated in
accordance with the Indenture and when delivered and paid for, will constitute
legal, valid and binding obligations of the Company.

      4. The Preferred Shares (including Preferred Shares issuable upon
conversion of or exchange for any Security), which may be represented by
Depository Shares, have been duly authorized and, when the final terms thereof
have been duly established and approved, certificates representing such
Preferred Shares have been duly executed by the Company, in each case pursuant
to the authority granted in the Resolutions, and when such certificates have
been delivered and paid for, such shares will be legally issued, fully paid and
non-assessable.

      5. The Deposit Agreements, when duly authorized and when executed and
delivered by the Company and assuming due authorization, execution and delivery
thereof by the applicable Depositary, will constitute legal, valid and binding
instruments of the Company enforceable against the Company in accordance with
their respective terms.

      6. The Common Shares (including Common Shares issuable upon conversion of
or exchange for any Security) have been duly authorized and, when issued and
delivered pursuant to the authority granted in the Resolutions and paid for,
will be legally issued, fully paid and non-assessable.

      7. The Warrant Agreements, when duly authorized and when executed and
delivered by the Company and assuming due authorization, execution and delivery
thereof by the applicable Warrant Agent, will constitute legally binding
instruments of the Company enforceable against the Company in accordance with
their respective terms.

      8. The Warrants have been duly authorized and, when the final terms
thereof have been duly established and approved, certificates representing such
Warrants have been duly executed by the Company, in each case pursuant to the
authority granted in the Resolutions, and when executed, countersigned in
accordance with the applicable Warrant Agreement and when delivered and paid
for, will constitute legal, valid and binding obligations of the Company.

      9. The Guaranteed Debt Securities, when duly executed and authenticated in
accordance with the B.V. Indenture and when delivered and paid for, will have
been duly authorized by, and will constitute legal, valid and binding
obligations of, Corning Finance B.V.

      10. The Guarantees, when executed and delivered by the Company, will have
been duly authorized and will constitute legally binding instruments of the
Company enforceable against the Company in accordance with their respective
terms.
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      The opinions set forth above are subject, as to enforcement, to (i)
bankruptcy, insolvency (including, without limitation, all laws relating to
fraudulent transfers), reorganization, moratorium or other similar laws relating
to or affecting the enforcement of creditors' rights generally, and (ii) general
equitable principles (regardless of whether enforcement is considered in a
proceeding in equity or at law).

      I hereby consent to the use of this opinion as an exhibit to the
Registration Statement and to the use of my name under the heading "Validity of
Securities" in the related prospectus.

                                          Very truly yours,

                                          /s/ William D. Eggers