Other Current Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Mar. 29, 2014	Dec. 28, 2013
Summary of other current liabilities
Accrued warranty	$ 3,575	$ 3,426
Accrued professional services	799	545
Customer deposits	947	867
Fair value of contingent payments to Zygo Corporation related to acquisition - current portion	1,205	1,344
Other	1,659	1,811
Total other current liabilities	$ 8,185	$ 7,993

Carrying value as of the balance sheet date of obligations incurred through that date and payable for professional fees, such as for legal and accounting services received. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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