Condensed Consolidated Balance Sheets (USD $)	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 6,033,685	$ 8,190,302
Accounts receivable, net of allowance	2,909,542	2,425,417
Inventories	4,317,117	3,931,007
Other current assets	421,049	510,710
Total current assets	13,681,393	15,057,436
Property and equipment:
Leasehold improvements	139,970	139,970
Equipment at customers	3,634,288	3,365,636
Machinery and equipment	5,728,949	5,597,385
Property and equipment, gross	9,503,207	9,102,991
Accumulated depreciation and amortization	(7,209,110)	(6,849,543)
Property and equipment, net	2,294,097	2,253,448
Intangible and other assets, net	851,549	851,737
Total assets	16,827,039	18,162,621
Current liabilities:
Accounts payable	2,061,927	1,594,147
Accrued expenses	1,465,567	1,737,312
Current portion of long-term debt	1,603,351	994,898
Total current liabilities	5,130,845	4,326,357
Deferred gain on sale and leaseback of property	461,855	495,515
Long-term debt, less current portion	3,320,853	3,915,949
Total liabilities	8,913,553	8,737,821
Commitments and contingencies
Stockholders' equity:
Common stock, $.004 par value per share, 40,000,000 shares 19,502,629 and 19,324,549 shares issued at March 31, 2014 and December 31, 2013, respectively, including shares held in treasury	78,011	77,298
Common stock held in treasury, at cost - 86,000 shares	(101,480)	(101,480)
Additional paid-in capital	19,276,929	18,939,869
Accumulated deficit	(25,277,614)	(23,428,527)
Total stockholders' equity	7,913,486	9,424,800
Total liabilities and stockholders' equity	16,827,039	18,162,621
Series A Convertible Preferred Stock [Member]
Stockholders' equity:
Preferred stock	8,802,000	8,802,000
Series A Exchangeable Preferred Stock [Member]
Stockholders' equity:
Preferred stock	$ 5,135,640	$ 5,135,640