Balance Sheets (USD $)	Mar. 31, 2013	Mar. 31, 2012
Current assets:
Cash and cash equivalents	$ 126,224	$ 564,671
Accounts receivable, net of allowance for doubtful accounts of $9,000 at March 31, 2013 and $15,500 at March 31, 2012	985,770	1,427,966
Inventories, net of reserve for obsolescence of $51,000 at March 31, 2013 and $117,000 at March 31, 2012	2,929,302	2,489,008
Prepaid expenses	65,891	28,568
Total current assets	4,107,187	4,510,213
Equipment, at cost:
Furniture, fixtures and equipment	2,691,057	2,497,471
Customer-site equipment	931,060	819,403
Equipment-in-progress	774,004	777,839
Accumulated depreciation	(2,767,195)	(2,476,004)
Equipment, net	1,628,926	1,618,709
Patents, net of accumulated amortization of $190,770 at March 31, 2013 and $169,084 at March 31, 2012	237,606	272,714
Other assets	9,215	7,415
TOTAL ASSETS	5,982,934	6,409,051
Current liabilities:
Accounts payable	823,347	1,039,923
Accrued compensation	319,116	283,366
Other accrued liabilities	446,171	349,136
Total current liabilities	1,588,634	1,672,425
Commitments and contingencies
Shareholders' equity:
Preferred stock, no par value: 10,000,000 shares authorized; none issued and outstanding
Common stock and additional paid-in capital, no par value: 100,000,000 shares authorized; 8,210,100 and 7,955,100 shares issued and outstanding at March 31, 2013 and 2012, respectively	21,569,993	21,296,646
Accumulated (deficit)	(17,175,693)	(16,560,020)
Total shareholders' equity	4,394,300	4,736,626
TOTAL LIABILITIES AND SHAREHOLDERS' EQUITY	$ 5,982,934	$ 6,409,051