CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 29, 2018	Sep. 30, 2017	Sep. 29, 2018	Sep. 30, 2017
Revenues	$ 85,917	$ 70,967	$ 196,541	$ 143,651
Cost of sales	46,850	44,435	104,276	90,699
Gross profit	39,067	26,532	92,265	52,952
Operating expenses:
Selling, service and administration	10,838	11,648	20,968	24,456
Research, development and engineering	9,154	8,274	19,213	17,208
Restructuring Costs	0	2,162	0	3,373
Net operating expenses	19,992	22,084	40,181	45,037
Operating (loss) income	19,075	4,448	52,084	7,915
Non-operating (expense) income:
Interest and other (expense) income, net	383	(229)	835	(413)
Other Nonoperating Income (Expense)	383	(229)	835	(413)
Income (loss) before income taxes	19,458	4,219	52,919	7,502
Provision for (benefit from) income taxes	2,623	(41)	4,941	340
Net (loss) income	$ 16,835	$ 4,260	$ 47,978	$ 7,162
Net (loss) income per share - basic	$ 0.49	$ 0.13	$ 1.39	$ 0.21
Net (loss) income per share - diluted	$ 0.47	$ 0.12	$ 1.34	$ 0.21
Weighted average number of shares - basic	34,606	33,861	34,529	33,647
Weighted Average Number of Shares Outstanding, Diluted	35,959	34,874	35,916	34,716
Product [Member]
Revenues	$ 71,263	$ 60,316	$ 168,120	$ 122,409
Cost of sales	40,539	38,179	90,633	79,605
Service Market [Member]
Revenues	14,654	10,651	28,421	21,242
Cost of sales	$ 6,311	$ 6,256	$ 13,643	$ 11,094