1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details 1) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	May 31, 2014	May 31, 2013	May 31, 2012
Stock-based compensation in the form of employee stock options and ESPP shares included in:
Total stock-based compensation	$ 853	$ 601	$ 709
Effect on net income (loss) per share, Basic	$ 0.08	$ 0.06	$ 0.08
Effect on net income (loss) per share, Diluted	$ 0.07	$ 0.06	$ 0.08
Cost Of Sales
Stock-based compensation in the form of employee stock options and ESPP shares included in:
Total stock-based compensation	43	36	87
Selling, General and Administrative
Stock-based compensation in the form of employee stock options and ESPP shares included in:
Total stock-based compensation	643	446	430
Research And Development
Stock-based compensation in the form of employee stock options and ESPP shares included in:
Total stock-based compensation	$ 167	$ 119	$ 192