CONSOLIDATED STATEMENTS OF OPERATIONS (in thousands, except per share amounts) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Net Sales	$ 29,224	$ 34,051
Cost of goods sold	11,868	13,992
Gross margin	17,356	20,059
Operating expenses:
Research and development	7,361	6,896
Selling, general and administrative	8,257	8,116
Total operating expenses	15,618	15,012
Operating income	1,738	5,047
Non-operating income (expense):
Interest income	37	29
Gain on sale of assets	19	366
Foreign currency transaction gain (loss)	103	(281)
Total non-operating income (expense)	159	114
Income before income taxes	1,897	5,161
Income tax (expense) benefit	(291)	288
Net income	$ 1,606	$ 5,449
Basic earnings per share	$ 0.19	$ 0.67
Diluted earnings per share	$ 0.19	$ 0.65
Weighted-average basic shares	8,378	8,149
Weighted-average diluted shares	8,514	8,436