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                                                                     EXHIBIT 5.1

                                 August 27, 1999

IRIDEX Corporation
1212 Terra Bella Avenue
Mountain View, California  94043

        RE:     REGISTRATION STATEMENT ON FORM S-8

Ladies and Gentlemen:

        We have examined the Registration Statement on Form S-8 to be filed by
you with the Securities and Exchange Commission on or about August 27, 1999 (the
"Registration Statement") in connection with the registration under the
Securities Act of 1933, as amended, of a total of 150,000 shares of your Common
Stock reserved for issuance under the 1998 Stock Plan and 75,000 shares of your
Common Stock reserved for issuance under the 1995 Employee Stock Purchase Plan
(collectively, the "Shares") (collectively, the "Plans"). As legal counsel for
IRIDEX Corporation, we have examined the proceedings taken and are familiar with
the proceedings proposed to be taken by you in connection with the sale and
issuance of the Shares under the Plans.

        It is our opinion that, when issued and sold in the manner referred to
in the Plans and pursuant to the respective agreement which accompanies each
grant under the Plans, the Shares will be legally and validly issued, fully paid
and nonassessable.

        We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to the use of our name wherever it appears in the
Registration Statement and any amendments to it.


                                        Very truly yours,


                                        WILSON SONSINI GOODRICH & ROSATI
                                        Professional Corporation


                                        /s/ WILSON SONSINI GOODRICH & ROSATI
                                        Professional Corporation



