EXHIBIT 5.1

                                  June 10, 1999

ProtoSource Corporation
2800 28th Street, Suite 170
Santa Monica, California 90405

       RE:  REGISTRATION STATEMENT ON FORM S-3

Ladies and Gentlemen:

     We have examined the Registration  Statement on Form S-3 to be filed by you
with the  Securities  and  Exchange  Commission  on or about June 11,  1999 (the
"Registration   Statement")  in  connection  with  the  registration  under  the
Securities Act of 1933, as amended,  of a total of 1,568,667  shares  underlying
common stock  purchase  warrants (the  "Shares"),  to be offered for sale by the
selling stockholders named therein. As legal counsel for ProtoSource Corporation
we have examined the proceedings taken in connection with the sale of the Shares
by the  selling  stockholders  in  the  manner  set  forth  in the  Registration
Statement in the Section entitled "Plan of Distribution." It is our opinion that
the Shares are legally and validly issued, fully paid and nonassessable.

     We  consent to the use of this  opinion  as an exhibit to the  Registration
Statement,  including the prospectus  constituting  a part thereof,  and further
consent to the use of our name wherever it appears in the Registration Statement
and any amendments thereto.

                                              Very truly yours,



                                              Gary A. Agron
                                              Attorney at Law


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