Balance Sheets (USD $)	Mar. 31, 2012	Mar. 31, 2011
ASSETS
Cash and cash equivalents	$ 1,544,536	$ 952,209
Marketable securities, short term	17,551,629	7,970,358
Accounts receivable, net of allowance for uncollectible accounts of $15,000	2,684,840	3,596,239
Inventories	3,229,376	3,343,857
Prepaid expenses and other assets	1,159,852	1,185,306
Total current assets	26,170,233	17,047,969
Fixed assets
Machinery and equipment	7,488,211	6,178,207
Leasehold improvements	720,882	612,682
Gross fixed assets	8,209,093	6,790,889
Less accumulated depreciation	5,697,861	5,259,773
Net fixed assets	2,511,232	1,531,116
Marketable securities, long term	54,445,298	53,257,140
Total assets	83,126,763	71,836,225
LIABILITIES AND SHAREHOLDERS' EQUITY
Accounts payable	663,702	731,580
Accrued payroll and other	867,331	987,403
Deferred taxes	136,872	146,693
Total current liabilities	1,667,905	1,865,676
Shareholders' equity
Common stock, $0.01 par value, 6,000,000 shares authorized; 4,824,745 issued and outstanding as of March 31, 2012 and 4,776,198 issued and outstanding as of March 31, 2011	48,247	47,762
Additional paid-in capital	20,974,477	20,894,766
Accumulated other comprehensive income	1,087,456	1,060,438
Retained earnings	59,348,678	47,967,583
Total shareholders' equity	81,458,858	69,970,549
Total liabilities and shareholders' equity	$ 83,126,763	$ 71,836,225