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                                                                      EXHIBIT 11

                           SI DIAMOND TECHNOLOGY, INC.

                     COMPUTATION OF (LOSS) PER COMMON SHARE

<TABLE>
<CAPTION>
                                                               Three months ended                            Year ended
                                                                  December 31,                              December 31,
                                                        ---------------------------------         --------------------------------
                                                            2000                 1999                 2000                1999
                                                        ------------         ------------         ------------         -----------
<S>                                                     <C>                  <C>                  <C>                  <C>
Computation of income ( loss ) per common share:

   Net income (loss) applicable to common
          shareholders                                  $ (2,901,179)        $   (670,481)        $ (7,761,342)        $   977,971

   Weighted average number of common shares               59,671,805           53,651,504           57,379,240          51,188,385

   Net income (loss) per common share                   $      (0.05)        $      (0.01)        $      (0.14)        $      0.02


Computation of income ( loss ) per common
   share assuming full dilution:

   Net income (loss) applicable to common
      stockholders                                                                                                         977,971

   Plus: Income impact of assumed conversions
         Series G                                                                                                          140,163
         Interest                                                                                                           21,832

   Income available to common stockholders                                                                               1,139,966

   Weighted average number of common
          shares outstanding                                                                                            51,188,385

   Plus incremental shares from dilutive securities
        Convertible preferred stock                                                                                      1,625,116
        Convertible notes payable                                                                                          635,168
        Warrants                                                                                                           391,647
        Options                                                                                                          3,561,388

   Adjusted weighted average number of
         common shares outstanding                                                                                      57,401,654

Net income (loss) per common share                                                                                            0.02
</TABLE>

    No computation of diluted loss per common share is included for the 2000
      periods or for the three months ended December 31, 1999 because such
          computation results in an antidilutive loss per common share.


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