CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Cash flows from operating activities:
Net loss	$ (3,305,146)	$ (4,250,371)	$ (4,648,303)
Adjustments to reconcile net loss to net cash used in operations:
Depreciation and amortization	1,152,929	1,118,243	1,119,227
Loss on disposal of equipment	7,617	8,447	5,358
Amortization of premium on marketable securities	47,559	35,277	18,910
Share-based consulting expense	1,623	5,448	11,261
Share-based compensation expense	810,016	679,471	422,893
Deferred income taxes	(29,053)	(40,116)	26,192
Deferred rent	(36,902)	(35,228)	(35,228)
Changes in operating assets and liabilities:
Accounts receivable, net	108,495	(653,110)	(752,970)
Inventories	(25,370)	(29,719)	(328,754)
Other current assets	(205,778)	(17,510)	(85,529)
Accounts payable	30,925	(59,025)	170,326
Accrued liabilities	138,875	63,981	711,832
Accrued pension liability, net	79,598	45,843	(11,680)
Net cash used in operating activities	(1,224,612)	(3,128,369)	(3,376,465)
Cash flows from investing activities:
Proceeds from maturity of available-for-sale marketable securities	4,200,000	10,018,252	2,261,568
Proceeds from maturity of held-to-maturity marketable securities	6,920,000	3,740,000	5,000,000
Purchases of available-for-sale marketable securities	(8,425,034)	(3,046,270)	(12,318,915)
Purchases of held-to-maturity marketable securities	(2,500,000)	(8,840,000)	(5,000,000)
Purchases of property, plant and equipment	(189,929)	(267,944)	(229,131)
Proceeds from sale of property, plant and equipment	5,591	0	0
Payments for intangible assets	(17,455)	(77,738)	(35,643)
Net cash provided by (used in) investing activities	(6,827)	1,526,300	(10,322,121)
Cash flows from financing activities:
Net proceeds from public offering of common stock	0	0	14,917,059
Net proceeds from exercise of warrants and options	150,000	208,825	2,542,207
Net cash provided by financing activities	150,000	208,825	17,459,266
Effect of exchange rates on cash and cash equivalents	(37,923)	(17,103)	(8,376)
Net increase (decrease) in cash and cash equivalents	(1,119,362)	(1,410,347)	3,752,304
Cash and cash equivalents at beginning of year	4,653,226	6,063,573	2,311,269
Cash and cash equivalents at end of year	3,533,864	4,653,226	6,063,573
Supplemental disclosure of cash flow information:
Cash paid during the year for interest	707	57	17
Cash paid during the year for income tax	$ 57,288	$ 39,005	$ 17,549