CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2014	Jan. 31, 2013
Revenues:
Sales of products	$ 3,699	$ 1,709	$ 19,724	$ 6,769
Services	298	297	1,013	924
Total revenues	3,997	2,006	20,737	7,693
Cost of sales:
Cost of product sales	2,083	1,372	12,829	4,222
Cost of services	76	146	314	349
Total cost of sales	2,159	1,518	13,143	4,571
Gross profit	1,838	488	7,594	3,122
Selling, general and administrative expenses	688	580	2,112	1,803
Income (loss) from operations	1,150	(92)	5,482	1,319
Other income:
Interest and dividend income	0	0	1	0
Income (loss) before provision for income taxes	1,150	(92)	5,483	1,319
Provision (benefit) for income taxes	200	(3)	1,899	20
Net income (loss)	$ 950	$ (89)	$ 3,584	$ 1,299
Net income (loss) per share:
Basic (in dollars per share)	$ 0.07	$ (0.01)	$ 0.27	$ 0.10
Weighted average shares used in computation of net income (loss) per share:
Basic (in shares)	12,963	12,963	12,963	12,963