CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) (USD $)	6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Cash flows from operating activities:
Net loss	$ (1,658,881)	$ (2,609,794)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	576,665	552,275
Loss on disposal of equipment	2,797	6,475
Amortization of premium on marketable securities	26,716	17,039
Share-based consulting expense	1,623	2,787
Share-based compensation expense	353,060	288,754
Deferred income tax expense (benefit)	2,860	(3,040)
Deferred rent credit	(18,374)	(17,614)
Changes in operating assets and liabilities:
Accounts receivable, net	100,537	(196,435)
Inventories	(175,833)	(65,281)
Other current assets	(102,998)	(143,370)
Accounts payable	26,516	(27,130)
Accrued liabilities	10,040	(20,515)
Accrued pension liability, net	(36,401)	(65,303)
Net cash used in operating activities	(891,673)	(2,281,152)
Cash flows from investing activities:
Proceeds from maturity of held-to-maturity investments	3,800,000	3,500,016
Proceeds from maturity of available-for-sale investments	2,000,000	7,518,252
Purchases of held-to-maturity investments	(1,780,000)	(5,280,042)
Purchases of available-for-sale investments	(3,218,286)	0
Purchases of property, plant and equipment	(93,981)	(106,325)
Proceeds from sale of property, plant and equipment	7,276	0
Purchase of intangible assets	(4,440)	(67,198)
Net cash provided by investing activities	710,569	5,564,703
Cash flows from financing activities:
Net proceeds from exercise of options	150,000	207,050
Net cash provided by financing activities	150,000	207,050
Effect of exchange rate changes on cash and cash equivalents	(10,580)	(15,824)
Net (decrease) increase in cash and cash equivalents	(41,684)	3,474,777
Cash and cash equivalents at beginning of period	4,653,226	6,063,573
Cash and cash equivalents at end of period	4,611,542	9,538,350
Cash paid during the period for interest	0	57
Cash paid during the period for income taxes	$ 35,507	$ 24,074