Consolidated Condensed Balance Sheets (USD $)	Dec. 31, 2014	Mar. 31, 2014
Current assets:
Cash and cash equivalents	$ 7,217,340	$ 10,247,112
Short-term investments		63,029us-gaap_ShortTermInvestments
Accounts receivable, net	895,508us-gaap_AccountsReceivableNet	960,419us-gaap_AccountsReceivableNet
Costs and estimated earnings in excess of billings on uncompleted contracts	36,760	341,255
Inventories	9,651,769us-gaap_InventoryNet	10,054,422us-gaap_InventoryNet
Prepaid expenses and other current assets	337,789	263,988
Total current assets	18,139,166us-gaap_AssetsCurrent	21,930,225us-gaap_AssetsCurrent
Property and equipment, at cost:
Land	1,683,330us-gaap_Land	1,683,330us-gaap_Land
Building	4,516,301us-gaap_BuildingsAndImprovementsGross	4,516,301us-gaap_BuildingsAndImprovementsGross
Machinery and equipment	7,809,643us-gaap_MachineryAndEquipmentGross	7,706,066us-gaap_MachineryAndEquipmentGross
Property, plant and equipment, gross	14,009,274us-gaap_PropertyPlantAndEquipmentGross	13,905,697us-gaap_PropertyPlantAndEquipmentGross
Less accumulated depreciation	(7,113,238)	(6,337,924)
Net property and equipment	6,896,036us-gaap_PropertyPlantAndEquipmentNet	7,567,773us-gaap_PropertyPlantAndEquipmentNet
Patent costs, net of accumulated amortization of $891,090 and $878,707, respectively	239,528	227,015
Trademark costs, net of accumulated amortization of $71,943 and $68,718, respectively	103,898	107,123
Other assets	99,706us-gaap_OtherAssetsNoncurrent	2,997us-gaap_OtherAssetsNoncurrent
Total assets	25,478,334us-gaap_Assets	29,835,133us-gaap_Assets
Liabilities and Stockholders' Equity
Accounts payable	168,558us-gaap_AccountsPayableCurrent	386,293us-gaap_AccountsPayableCurrent
Other current liabilities	1,505,116	1,491,745
Billings in excess of costs and estimated earnings on uncompleted contracts	39,520us-gaap_BillingsInExcessOfCostCurrent
Total current liabilities	1,713,194us-gaap_LiabilitiesCurrent	1,878,038us-gaap_LiabilitiesCurrent
Long-term deferred compensation under executive employment agreements	257,657	182,100
Total liabilities	1,970,851us-gaap_Liabilities	2,060,138us-gaap_Liabilities
Commitments and contingencies
Stockholders' equity:
Common stock, $.01 par value, 50,000,000 shares authorized; 39,999,984 and 39,777,767 shares issued and outstanding	400,000us-gaap_CommonStockValue	397,778us-gaap_CommonStockValue
Additional paid-in capital	121,728,244	121,325,762
Accumulated deficit	(98,620,761)	(93,948,545)
Total stockholders' equity	23,507,483us-gaap_StockholdersEquity	27,774,995us-gaap_StockholdersEquity
Total liabilities and stockholders' equity	$ 25,478,334	$ 29,835,133

Net carrying amount after accumulated amortization as of the balance sheet date of the costs pertaining to the exclusive legal rights granted to the owner of the patent to exploit an invention or a process for a period of time specified by law. Such costs may have been expended to directly apply and receive patent rights, or to acquire such rights.

No definition available.