Condensed Consolidated Statements of Operations (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 29, 2013	Jun. 30, 2012	Jun. 29, 2013	Jun. 30, 2012
Net revenues:
Products	$ 26,533	$ 41,556	$ 39,612	$ 89,414
Service	8,019	11,625	19,492	19,259
Total net revenues	34,552	53,181	59,104	108,673
Costs of net revenues:
Cost of products	14,832	22,627	22,792	47,446
Cost of service	4,593	5,158	10,041	10,128
Amortization of intangible assets	647	637	1,305	1,274
Total costs of net revenues	20,072	28,422	34,138	58,848
Gross profit	14,480	24,759	24,966	49,825
Operating expenses:
Research and development	8,321	7,644	15,768	15,120
Selling	6,613	7,041	13,545	14,252
General and administrative	5,507	5,583	11,019	11,664
Amortization of intangible assets	195	195	393	387
Total operating expenses	20,636	20,463	40,725	41,423
Income (loss) from operations	(6,156)	4,296	(15,759)	8,402
Other income (expense)
Interest income	20	33	45	85
Interest expense	(205)	(264)	(431)	(533)
Other, net	(637)	(49)	(597)	(224)
Total other expense, net	(822)	(280)	(983)	(672)
Income (loss) before income taxes	(6,978)	4,016	(16,742)	7,730
Provision for (benefit from) income taxes	(2,412)	(490)	(6,594)	1,521
Net income (loss)	$ (4,566)	$ 4,506	$ (10,148)	$ 6,209
Net income (loss) per share:
Basic (dollars per share)	$ (0.20)	$ 0.19	$ (0.44)	$ 0.27
Diluted (dollars per share)	$ (0.20)	$ 0.19	$ (0.44)	$ 0.26
Shares used in per share calculation:
Basic (shares)	23,138	23,395	23,240	23,372
Diluted (shares)	23,138	23,877	23,240	23,924