CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Net revenues:
Total net revenues	$ 13,813	$ 28,842	$ 30,054	$ 47,682
Cost of net revenues:
Total cost of net revenues	10,705	17,422	23,892	28,105
Gross profit	3,108	11,420	6,162	19,577
Operating expenses:
Research and development	3,894	3,707	7,519	6,991
Selling, general and administrative	5,525	5,609	11,455	11,581
Total operating expenses	9,419	9,316	18,974	18,572
Income (loss) from operations	(6,311)	2,104	(12,812)	1,005
Interest income and other income (expense), net	20	62	50	204
Income (loss) before provision for (benefit from) income taxes	(6,291)	2,166	(12,762)	1,209
Provision for (benefit from) income taxes	(165)	642	(132)	909
Net income (loss)	$ (6,126)	$ 1,524	$ (12,630)	$ 300
Net income (loss) per share:
Basic	$ (0.25)	$ 0.06	$ (0.52)	$ 0.01
Diluted	$ (0.25)	$ 0.06	$ (0.52)	$ 0.01
Weighted average common shares outstanding:
Basic	24,241	23,561	24,137	23,522
Diluted	24,241	23,906	24,137	23,953
Systems and components
Net revenues:
Total net revenues	$ 10,651	$ 22,725	$ 23,710	$ 36,561
Cost of net revenues:
Total cost of net revenues	8,624	13,812	18,588	21,579
Technology development
Net revenues:
Total net revenues	3,162	6,117	6,344	11,121
Cost of net revenues:
Total cost of net revenues	$ 2,081	$ 3,610	$ 5,304	$ 6,526