Stock-Based Compensation (Tables)

6 Months Ended

Jul. 04, 2015

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs

Stock-based compensation expense recognized under ASC Topic 718, Compensation – Stock Compensation (“ASC 718”), for employees and directors and the effect on our Condensed Consolidated Statements of Operations were as follows:



	Three Months Ended				Six Months Ended
(In thousands)	July 4, 2015		June 28, 2014		July 4, 2015		June 28, 2014
Cost of sales	$	217	$	208	$	444	$	398
Research, development, and engineering	801		700		1,661		1,339
Selling, general and administrative expenses	2,791		3,197		6,095		6,330
Total stock-based compensation expense	$	3,809	$	4,105	$	8,200	$	8,067

Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions

We used the following weighted-average assumptions to estimate the fair value of our stock options granted:



	Three Months Ended		Six Months Ended
	July 4, 2015	June 28, 2014	July 4, 2015	June 28, 2014
Expected life (in years)	5.9	5.9	5.9	5.9
Risk-free interest rate	1.5%	1.7%	1.6%	1.6%
Volatility	43%	47%	44%	47%
Dividend yield	—%	—%	—%	—%