                                                        Exhibit 5.1


May 27, 2004


Energy Conversion Devices, Inc.
2956 Waterview Drive
Rochester Hills, Michigan 48309

   Re:   Post Effective Amendment No. 2 to Registration
         Statement on Form S-1 No. 333-111500

Ladies and Gentlemen:

      I am the General Counsel of Energy Conversion Devices, Inc., a Delaware
corporation (the "Company"). I am issuing this opinion in connection with the
preparation of Post Effective Amendment No. 2 to Registration Statement on
Form S-1 No. 333-111500 (the "Post Effective Amendment No. 2") being filed on
the date hereof with the Securities and Exchange Commission (the "SEC") under
the Securities Act of 1933, as amended (the "Act") relating to the offering
from time to time, in one or more offerings, by certain of the Company's
stockholders under Rule 415 of the General Rules and Regulations of the SEC
promulgated under the Act, of an aggregate of 5,385,830 shares of the
Company's Common Stock, par value $.01 per share (the "Shares").

      In connection with the delivery of this opinion, I have examined
originals or copies of the restated certificate of incorporation of the
Company, as amended and approved by the board of directors and stockholders
of the Company, the bylaws of the Company, as amended and approved by the
board of directors and stockholders of the Company, the Post Effective
Amendment No. 2, resolutions adopted by the Board of Directors and
stockholders of the Company, and such other records, agreements, instruments,
certificates and other documents of public officials, the Company and its
officers and representatives, and have made such inquiries of the Company and
its officers and representatives, as I have deemed necessary or appropriate
in connection with the opinions set forth herein. I am familiar with the
proceedings taken by the Company in connection with the authorization,
registration, issuance and sale of the Shares. With respect to certain
factual matters material to my opinion, I have relied upon representations
from, or certificates of, officers of the Company. In making such examination
and rendering the opinions set forth below, I have assumed without
verification the genuineness of all signatures, the authenticity of all
documents submitted to me as originals, the authenticity of the originals of
such documents submitted to me as certified copies, the conformity to
originals of all documents submitted to me as copies, the authenticity of the
originals of such latter documents, and that all documents submitted to me as
certified copies are true and correct copies of such originals.

      I am a member of the Bar of the State of Michigan, and I have not
considered, and I express no opinion as to, the laws of any jurisdiction
other than the laws of the United States of America, the State of Michigan
and the General Corporation Law of the State of Delaware.

      Based upon and subject to the foregoing qualifications, assumptions and
limitations and the further limitations set forth below, I hereby advise you
that in my opinion, the Shares have been duly authorized by all necessary
corporate action on the part of the Company, have been validly issued and are
fully paid and nonassessable.


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Energy Conversion Devices, Inc.
May 27, 2004
Page 2


      I hereby consent to the filing of this opinion with the SEC as Exhibit
5.1 to the Post Effective Amendment No. 2 and to the use of my name under the
heading "Legal Matters" in the prospectus which is part of the Post Effective
Amendment No. 2. In giving this consent, I do not hereby admit that I am in
the category of persons whose consent is required under Section 7 of the Act
or the rules and regulations of the SEC.

      I do not find it necessary for the purposes of this opinion, and
accordingly I do not purport to cover herein, the application of the
securities or "Blue Sky" laws of the various states to the issuance and sale
of the Shares.

      This opinion is limited to the specific issues addressed herein, and no
opinion may be inferred or implied beyond that expressly stated herein. I
assume no obligation to revise or supplement this opinion should the General
Corporation Law of the State of Delaware be changed by legislative action,
judicial decision or otherwise.

      This opinion is furnished to you in connection with the filing of the
Post Effective Amendment No. 2 and is not to be used, circulated, quoted or
otherwise relied upon for any other purpose.



                                          Very truly yours,


                                          /s/ Roger John Lesinski
                                          Roger John Lesinski
                                          General Counsel



