Note 6 - Stock-Based Compensation (Tables)

6 Months Ended

Nov. 24, 2013

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

Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table Text Block]

	Three Months Ended November 24, 2013		Three Months Ended November 25, 2012		Six Months Ended November 24, 2013		Six Months Ended November 25, 2012
Research and development	$	—	$	104,000	$	14,000	$	214,000
Sales, general and administrative	$	361,000	$	219,000	$	625,000	$	457,000
Total stock-based compensation	$	361,000	$	323,000	$	639,000	$	671,000