1. ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
	May. 31, 2015	May. 31, 2014	May. 31, 2013
STOCK BASED COMPENSATION:
Stock-based compensation costs capitalized as part of inventory	$ 20	$ 24	$ 0
Stock-based compensation expense related to stock options	857	723	551
Stock-based compensation related to the ESPP	140	$ 130	$ 50
Compensation cost related to purchase rights under the ESPP but not yet recognized	$ 135
Weighted average period for recognition of costs	1 year 3 months 18 days
ESPP shares issued	87,000	120,000	156,000
EARNINGS PER SHARE:
Options not included in the computation of diluted net (loss) income per share (in thousands)	3,686,000	301,000	2,956,000
ESPP
STOCK BASED COMPENSATION:
ESPP purchase rights granted	222,000	172,000	27,000
ESPP shares issued	87,000	120,000	156,000
ESPP shares available for issuance	268,000
EARNINGS PER SHARE:
Options not included in the computation of diluted net (loss) income per share (in thousands)	175,000	131,000	178,000
1996 Stock Option Plan and 2006 Equity Incentive Plan
STOCK BASED COMPENSATION:
Unrecognized stock-based compensation	$ 1,873
Estimated forfeitures of unvested stock based awards, amount	$ 5
Weighted average period for recognition of costs	2 years 10 months 24 days