STOCK-BASED COMPENSATION (Tables)

6 Months Ended

Jun. 28, 2015

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

The Black-Scholes model requires the input of highly subjective assumptions, which are summarized in the table below for the three and six months ended June 28, 2015 and June 29, 2014:



	Three Months Ended		Six Months Ended
	June 28, 2015	June 29, 2014	June 28, 2015	June 29, 2014
Expected dividend yield	—	—	—	—
Expected stock price volatility	65%	67%	66%	67%
Risk-free interest rate	1.3%	1.3%	1.1%	1.3%
Expected life of options in years	4.0	4.0	4.0	4.0

Schedule of Stock-Based Compensation

Our stock-based compensation for the three and six months ended June 28, 2015 and June 29, 2014 was as follows (in thousands):



	Three Months Ended				Six Months Ended
	June 28, 2015		June 29, 2014		June 28, 2015		June 29, 2014
Stock-based compensation by type of award:
Stock options	$	266	$	249	$	511	$	496
Restricted stock units	307		126		573		165
Employee stock purchase plan	5		12		10		24
	$	578	$	387	$	1,094	$	685
Stock-based compensation by category of expense:
Cost of goods sold	$	39	$	8	$	73	$	11
Research, development and engineering	70		47		133		87
Selling, general and administrative	469		332		888		587
	$	578	$	387	$	1,094	$	685