CONSOLIDATED STATEMENTS OF OPERATIONS (in thousands, except per share amounts) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Net Sales	$ 6,588	$ 6,159	$ 17,002	$ 17,019
Cost of goods sold	2,945	2,990	7,743	8,270
Gross margin	3,643	3,169	9,259	8,749
Operating expenses:
Research and development	1,358	1,188	3,655	3,530
Selling, general and administrative	1,664	1,505	4,766	4,457
Total operating expenses	3,022	2,693	8,421	7,987
Operating income	621	476	838	762
Non-operating income (expense):
Interest income	11	30	34	88
Foreign currency transaction gain (loss)	(3)	(50)	41	(237)
Total non-operating income (expense)	8	(20)	75	(149)
Income before income taxes	629	456	913	613
Income tax (expense)	(4)	(17)	(12)	(24)
Net income	$ 625	$ 439	$ 901	$ 589
Basic earnings per share	$ 0.08	$ 0.06	$ 0.11	$ 0.07
Diluted earnings per share	$ 0.08	$ 0.05	$ 0.11	$ 0.07
Weighted-average basic shares	7,977	7,930	7,955	7,896
Weighted-average diluted shares	8,183	8,042	8,083	8,055