Condensed Consolidated Balance Sheets (Unaudited) (USD $)	Mar. 31, 2012	Dec. 31, 2011
Current assets:
Cash and cash equivalents	$ 20,829,033	$ 13,856,893
Accounts receivable, less allowance of $0 at March 31, 2012 and December 31, 2011	12,969,623	13,388,909
Inventory	8,109,179	10,354,707
Prepaid expenses and other current assets	1,176,980	1,894,014
Total current assets	43,084,815	39,494,523
Property, plant and equipment, net	8,084,985	8,686,840
Intangible assets, net	7,001,738	7,474,636
Total assets	58,171,538	55,655,999
Current liabilities:
Accounts payable	2,903,785	4,668,721
Accrued expenses	2,378,956	3,172,998
Product warranty reserve	1,091,147	1,210,909
Borrowings under line of credit		5,405,110
Deferred revenue	6,983,501	5,542,004
Other current liabilities	650,300	80,000
Total current liabilities	14,007,689	20,079,742
Common stock warrant liability	4,082,240	5,320,990
Other liabilities	1,247,335	1,219,602
Total liabilities	19,337,264	26,620,334
Stockholders' equity:
Common stock, $0.01 par value per share; 245,000,000 shares authorized; Issued (including shares in treasury): 37,933,447 at March 31, 2012 and 22,924,411 at December 31, 2011	379,335	229,244
Additional paid-in capital	800,368,988	784,213,871
Accumulated other comprehensive income	1,005,247	928,744
Accumulated deficit	(761,366,914)	(754,783,812)
Less common stock in treasury: 165,906 shares at March 31, 2012 and December 31, 2011	(1,552,382)	(1,552,382)
Total stockholders' equity	38,834,274	29,035,665
Total liabilities and stockholders' equity	$ 58,171,538	$ 55,655,999