UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2018	Jul. 02, 2017	Jul. 01, 2018	Jul. 02, 2017
Income Statement [Abstract]
Revenue	$ 3,122	$ 3,026	$ 5,886	$ 6,196
Cost of revenue	1,592	1,646	2,967	3,443
Gross profit	1,530	1,380	2,919	2,753
Operating expenses:
Research and development	2,366	2,319	5,065	4,746
Selling, general and administrative	2,610	2,614	5,171	5,028
Total operating expenses	4,976	4,933	10,236	9,774
Loss from operations	(3,446)	(3,553)	(7,317)	(7,021)
Interest expense	(32)	(21)	(56)	(82)
Interest income and other (expense), net	23	1	9	1
Loss before income taxes	(3,455)	(3,573)	(7,364)	(7,102)
Provision for income taxes	29	34	90	70
Net loss	$ (3,484)	$ (3,607)	$ (7,454)	$ (7,172)
Net loss per share:
Basic and Diluted	$ (0.04)	$ (0.05)	$ (0.09)	$ (0.10)
Weighted average shares outstanding:
Basic and Diluted	85,753	79,799	83,176	74,327