CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $)	6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Operating activities:
Net income	$ 2,211,395	$ 527,167
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	852,673	813,815
Amortization	505,394	506,337
Stock based compensation	383,795	563,667
Deferred income taxes	(76,228)	15,433
Changes in operating assets and liabilities:
Accounts receivable, net	3,600	(1,204,094)
Inventories	469,498	(20,175)
Prepaid expense and other current assets	(188,086)	(246,840)
Accounts payable	(767,485)	(398,174)
Income tax payable	(10,737)	171,883
Other current liabilities	182,668	(350,328)
Net cash provided by operating activities	3,566,487	378,691
Investing activities:
Purchase of property, plant and equipment	(1,849,729)	(913,199)
Purchases of patents	(26,310)	(251,880)
Sales and maturities of marketable securities	9,779,846	35,648,715
Purchases of marketable securities	(9,500,050)	(16,026,987)
Net cash (used in) provided by investing activities	(1,596,243)	18,456,649
Financing activities:
Proceeds from long-term debt		778,623
Payments on long-term debt		(18,640,808)
Repurchase of common stock		(1,088,619)
Proceeds from exercise of stock options	807,990	113,142
Net cash provided by (used in) financing activities	807,990	(18,837,662)
Effect of exchange rate on cash and cash equivalents	(407,852)	92,696
Increase in cash and cash equivalents	2,370,382	90,374
Cash and cash equivalents at beginning of period	13,921,363	8,722,935
Cash and cash equivalents at end of period	16,291,745	8,813,309
Supplemental Cash Flow Information
Cash paid for interest		164,178
Cash paid for income taxes	$ 376,472	$ 205,664