Equity and Stock Based Compensation Plans (Tables)

9 Months Ended

Sep. 28, 2013

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Assumption of stock option's fair value

	Three Months Ended				Nine Months Ended
	September 28, 2013		September 29, 2012		September 28, 2013		September 29, 2012
Stock Options
Expected life	4.6 years		4.6 years		4.5 years		4.5 years
Volatility	64.38	%	75.44	%	71.04	%	77.96	%
Risk free interest rate	1.52	%	0.74	%	1.00	%	0.84	%
Dividends	—		—		—		—
Employee Stock Purchase Plan
Expected life	0.5 years		0.5 years		0.5 years		0.5 years
Volatility	25.94	%	38.58	%	26.75	%	45.47	%
Risk free interest rate	0.10	%	0.16	%	0.11	%	0.12	%
Dividends	—		—		—		—

Stock-based compensation expense for all share-based payment awards

Stock-based compensation expense for all share-based payment awards made to the Company’s employees and directors pursuant to the employee stock option and employee stock purchase plans by function was as follows (in thousands):

	Three Months Ended				Nine Months Ended
	September 28, 2013		September 29, 2012		September 28, 2013		September 29, 2012
Cost of products	$	55	$	50	$	153	$	128
Cost of service	74		62		204		195
Research and development	412		289		1,092		952
Selling	476		451		1,418		1,374
General and administrative	789		630		2,149		1,886
Restructuring	896		—		896		—
Total stock-based compensation expense	$	2,702	$	1,482	$	5,912	$	4,535

Stock Options [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock option plans activity

A summary of activity under the Company’s stock option plans during the nine month period ended September 28, 2013, is as follows:

	Number of Shares Outstanding (Options)		Weighted Average Exercise Price		Weighted Average Remaining Contractual Term (Years)	Aggregate Intrinsic Value (in Thousands)
Options
Outstanding at December 29, 2012	2,020,319		$	12.01	4.44	$	6,770
Exercised	(218,474	)	7.46
Granted	374,700		15.22
Cancelled	(121,881	)	15.10
Outstanding at September 28, 2013	2,054,664		$	12.90	4.28	$	7,158
Exercisable at September 28, 2013	1,258,894		$	11.43	3.49	$	6,150

Restricted Stock Units (RSUs) [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Stock option plans activity

A summary of activity for RSUs during the nine month period ended September 28, 2013, is as follows:

	Number of RSUs		Weighted Average Fair Value
Outstanding RSU as of December 29, 2012	235,162		$	16.32
Granted	292,360		15.41
Released	(85,707	)	15.55
Cancelled	(9,518	)	14.41
Outstanding RSU as of September 28, 2013	432,297		$	16.05