Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 30, 2017	Dec. 31, 2016
Current assets:
Cash and cash equivalents	$ 34,899	$ 47,062
Marketable securities	82,130	82,899
Accounts receivable, net of allowances of $126 and $73, respectively	62,457	39,457
Inventories	52,860	38,837
Inventories-delivered systems	1,534	2,457
Prepaid expenses and other	6,234	5,667
Total current assets	240,114	216,379
Property, plant and equipment, net	44,810	44,226
Goodwill	10,232	8,940
Intangible assets, net	2,206	412
Deferred income tax assets	11,924	17,399
Other assets	413	474
Total assets	309,699	287,830
Current liabilities:
Accounts payable	13,857	11,342
Accrued payroll and related expenses	12,901	12,656
Deferred revenue	7,408	9,168
Other current liabilities	7,249	8,047
Income taxes payable	2,680	813
Total current liabilities	44,095	42,026
Deferred revenue	1,661	816
Income taxes payable	860	841
Deferred tax liability	179	20
Other long-term liabilities	521	353
Total liabilities	47,316	44,056
Commitments and contingencies (Note 9)
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: 24,628,722 and 25,070,889, respectively, issued and outstanding	26	25
Additional paid-in capital	255,368	271,969
Retained earnings (deficit)	9,113	(22,174)
Accumulated other comprehensive income (loss)	(2,124)	(6,046)
Total stockholders’ equity	262,383	243,774
Total liabilities and stockholders’ equity	$ 309,699	$ 287,830