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                                                                    Exhibit 31.1

                                   TVIA, INC.

                           CERTIFICATIONS PURSUANT TO
                                 SECTION 302 OF
                         THE SARBANES-OXLEY ACT OF 2002

                                  CERTIFICATION

I, Eli Porat, certify that:

1. I have reviewed this quarterly report on Form 10-Q of Tvia, Inc.;

2. Based on my knowledge, this quarterly report does not contain any untrue
statement of a material fact or omit to state a material fact necessary to make
the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this quarterly
report;

3. Based on my knowledge, the financial statements, and other financial
information included in this quarterly report, fairly present in all material
respects the financial condition, results of operations and cash flows of the
registrant as of, and for, the periods presented in this quarterly report;

4. The registrant's other certifying officer and I are responsible for
establishing and maintaining disclosure controls and procedures (as defined in
Exchange Act Rules 13a-15(e) and 15d-15(e)) for the registrant and we have:

         a) designed such disclosure controls and procedures, or caused such
         disclosure controls and procedures to be designed under our
         supervision, to ensure that material information relating to the
         registrant, including its consolidated subsidiaries, is made known to
         us by others within those entities, particularly during the period in
         which this quarterly report is being prepared;

         b) evaluated the effectiveness of the registrant's disclosure controls
         and procedures; and presented in this quarterly report our conclusions
         about the effectiveness of the disclosure controls and procedures as of
         the end of the period covered by this report based on such evaluation;

         c) disclosed in this report any change in the registrant's internal
         control over financial reporting that occurred during the registrant's
         most recent fiscal quarter that has materially affected, or is
         reasonably likely to materially affect, the registrant's internal
         control over financial reporting.

5. The registrant's other certifying officers and I have disclosed, based on our
most recent evaluation of internal control over financial reporting, to the
registrant's auditors and the audit committee of registrant's board of directors
(or persons performing the equivalent function):

         a) all significant deficiencies in the design or operation of internal
         control over financial reporting which are reasonably likely to
         adversely affect the registrant's ability to record, process, summarize
         and report financial data; and

         b) any fraud, whether or not material, that involves management or
         other employees who have a significant role in the registrant's
         internal control over financial reporting.

                                          Date: August 13, 2003

                                          /s/ Eli Porat
                                          --------------------------------------

                                          Eli Porat
                                          Chief Executive Officer and President