Balance Sheets (Unaudited) (USD $)	Jan. 31, 2012	Apr. 30, 2011
Current assets
Cash	$ 743,993	$ 667,897
Accounts receivable, trade (Net of allowance for doubtful accounts of $500 at July 31, 2011 and April 30, 2011)	157,194	150,748
Inventories	91,361	86,662
Prepaid expenses	25,267	25,315
Total current assets	1,017,815	930,622
Equipment and leasehold improvements
Equipment	203,120	198,906
Leasehold improvements	20,022	20,022
[PropertyPlantAndEquipmentGross]	223,142	218,928
Less accumulated depreciation and amortization	(212,156)	(204,557)
Total equipment and leasehold improvements, net	10,986	14,371
Other assets
Patents less accumulated amortization	13,032	13,825
Pending patents	143,925	137,622
Deposits	5,937	5,947
Total other assets	162,894	157,394
[Assets]	1,191,695	1,102,387
Current Liabilities
Accounts payable	12,571	15,249
Accrued compensation and payroll taxes	3,472	24,631
Income Taxes Payable	12,993
Other accrued expenses	5,692	5,692
Accrued vacation	20,692	16,244
Total current liabilities	55,420	61,816
Deferred income taxes	28,534	28,534
Shareholders equity
Common stock, no par value: 20,000,000 authorized shares issued: 14,935,511 shares outstanding at July 31, 2011 and April 30, 2011	660,988	660,988
Receivable from Affiliate	(19,699)	(19,699)
Retained earnings	466,452	370,748
Total Shareholders Equity	1,107,741	1,012,037
[LiabilitiesAndStockholdersEquity]	$ 1,191,695	$ 1,102,387