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                                  Exhibit 11.1

                    PHOTOELECTRON CORPORATION AND SUBSIDIARY
                         (A Development Stage Company)
                 STATEMENT OF COMPUTATION OF PER SHARE EARNINGS
<TABLE>
<CAPTION>
 
                                              1992          1993          1994          1995          1996
                                          ------------  ------------  ------------  ------------  ------------
 
<S>                                       <C>           <C>           <C>           <C>           <C>
Computation of Primary Loss Per Share     ($1,586,239)  ($2,267,460)  ($2,671,648)  ($4,117,158)  ($4,958,771)
   Net Loss                               
Shares                                    
   Weighted average shares outstanding        926,146      1,126,500    1,328,992     1,107,310     1,587,954
Add:  Shares issuable from assumed        
   exercise of stock options and          
   warrants and conversion of other       
   common stock equivalents issued            
   within one year prior to the           
   filing of this registration statement       33,106        33,106        33,106        33,106        33,106
                                          
Add:  Shares issuable from                
   assumed conversion of the preferred            ___           ___           ___           ___           ___
   stock upon closing of the offering      ----------    ----------    ----------    ----------    ----------
                                          
Weighted average common and common        
   equivalents shares outstanding             959,252     1,159,606     1,362,098     1,140,416     1,621,060
                                          
Loss per share:                           
   Net loss                                     (1.65)        (1.96)        (1.96)        (3.61)        (3.06)
                                          
Computation of Fully Diluted Loss Per     
Share                                     
   Net Loss                               ($1,586,239)  ($2,267,460)  ($2,671,648)  ($4,117,158)  ($4,958,771)
                                          
Shares:                                   
   Weighted average shares outstanding        926,146     1,126,500     1,328,992     1,107,310     1,587,954
                                          
Add:  Shares issuable from                
   assumed exercise of stock options and  
   warrants and conversion of common stock   
   equivalents                                 33,106        33,106        33,106        33,106        33,106
                                          
Add:  Shares issuable from                
   assumed conversion of the preferred            ___           ___           ___           ___           ___
   stock upon closing of the offering      ----------    ----------    ----------    ----------    ----------
                                          
Weighted average common and common            959,252     1,159,606     1,362,098     1,140,416     1,621,060       
   equivalents shares outstanding          ----------    ----------    ----------    ----------    ----------  
                                         
Loss per share:                                  
   Net Loss                                     (1.65)        (1.96)        (1.96)        (3.61)       ($3.06)
                                           ----------    ----------    ----------    ----------    ----------      
                                                                                                  
 
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<TABLE>
<CAPTION>
 
                                                     1996 Pro Forma
<S>                                              <C>
Computation of Primary Loss Per Share  
   Net Loss                                           ($4,958,771)

Shares                                 
   Weighted average shares outstanding                  1,587,954
Add:  Shares issuable from assumed         
   exercise of stock options and           
   warrants and conversion of other    
   common stock equivalents issued                   
   within one year prior to the                      
   filing of this registration statement                   33,106             
                                                     
Add:  Shares issuable from                              2,894,644
   assumed conversion of the preferred               
   stock upon closing of the offering       
                                         
Weighted average common and common        
   equivalents shares outstanding                       4,515,704
                                          
Loss per share:                           
   Net loss                                                ($1.10)
                                          
Computation of Fully Diluted Loss Per     
Share                                     
   Net Loss                                            $4,958,771
                                          
Shares:                                   
   Weighted average shares outstanding                  1,587,954
                                          
Add:  Shares issuable from                
   assumed exercise of stock options and  
   warrants and conversion of common stock 
   equivalents                                             33,106       
                                          
Add:  Shares issuable from                
   assumed conversion of the preferred     
   stock upon closing of the offering                   2,894,644
                                          
Weighted average common and common         
   equivalents shares outstanding                       4,515,704
                                          
Loss per share:                            
   Net Loss                                                ($1.10)


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