Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 28, 2014	Jun. 29, 2013	Jun. 28, 2014	Jun. 29, 2013
Net revenues:
Products	$ 39,224	$ 26,533	$ 82,504	$ 39,612
Service	8,805	8,019	17,101	19,492
Total net revenues	48,029	34,552	99,605	59,104
Costs of net revenues:
Cost of products	19,789	14,832	41,428	22,792
Cost of service	4,655	4,593	9,769	10,041
Amortization of intangible assets	677	647	1,351	1,305
Total costs of net revenues	25,121	20,072	52,548	34,138
Gross profit	22,908	14,480	47,057	24,966
Operating expenses:
Research and development	9,373	8,321	17,687	15,768
Selling	6,681	6,613	14,054	13,545
General and administrative	6,001	5,507	12,339	11,019
Amortization of intangible assets	107	195	215	393
Total operating expenses	22,162	20,636	44,295	40,725
Income (loss) from operations	746	(6,156)	2,762	(15,759)
Other income (expense):
Interest income	10	20	24	45
Interest expense	(96)	(205)	(196)	(431)
Other income (expense), net	(84)	(637)	168	(597)
Total other income (expense), net	(170)	(822)	(4)	(983)
Income (loss) before income taxes	576	(6,978)	2,758	(16,742)
Provision for (benefit from) income taxes	(12)	(2,412)	575	(6,594)
Net income (loss)	$ 588	$ (4,566)	$ 2,183	$ (10,148)
Net income (loss) per share:
Basic (dollars per share)	$ 0.02	$ (0.20)	$ 0.09	$ (0.44)
Diluted (dollars per share)	$ 0.02	$ (0.20)	$ 0.09	$ (0.44)
Weighted shares used in per share calculation:
Basic (shares)	23,939	23,138	23,825	23,240
Diluted (shares)	24,220	23,138	24,217	23,240