Condensed Consolidated Balance Sheets (Unaudited) (USD $) In Thousands, unless otherwise specified	Sep. 27, 2014	Dec. 28, 2013
Current assets:
Cash and cash equivalents	$ 35,625	$ 44,765
Marketable securities	48,748	48,097
Accounts receivable, net of allowances of $253 and $293, respectively	26,061	31,436
Inventories	35,762	34,520
Inventories-delivered systems	501	6,901
Prepaid expenses and other	9,356	10,519
Deferred income tax assets	2,922	14,516
Total current assets	158,975	190,754
Property, plant and equipment, net	50,736	47,439
Goodwill	11,039	11,743
Intangible assets, net	5,255	7,864
Deferred income tax assets	362	4,338
Other assets	593	696
Total assets	226,960	262,834
Current liabilities:
Accounts payable	5,948	10,604
Accrued payroll and related expenses	8,395	7,853
Deferred revenue	5,944	21,749
Other current liabilities	7,834	7,993
Income taxes payable	639	758
Total current liabilities	28,760	48,957
Deferred revenue	3,253	3,718
Income taxes payable	635	1,171
Deferred tax liability	2,701	0
Other long-term liabilities	1,673	1,615
Total liabilities	37,022	55,461
Commitments and contingencies (Note 17)
Stockholders’ equity:
Preferred stock, $0.001 par value; 3,000,000 shares authorized; no shares issued or outstanding	0	0
Common stock, $0.001 par value, 47,000,000 shares authorized; 24,156,554 shares and 23,537,275 shares, respectively, issued and outstanding	24	24
Additional paid-in capital	255,036	244,733
Accumulated deficit	(64,475)	(37,996)
Accumulated other comprehensive income (loss)	(647)	612
Total stockholders’ equity	189,938	207,373
Total liabilities and stockholders’ equity	$ 226,960	$ 262,834