CONDENSED CONSOLIDATED STATEMENTS OF INCOME (USD $) Share data in Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Jun. 30, 2012	Jul. 02, 2011
CONDENSED CONSOLIDATED STATEMENTS OF INCOME [Abstract]
Net sales	$ 16,059,000	$ 18,058,000
Cost of sales	8,565,000	8,992,000
Gross profit	7,494,000	9,066,000
Research and development	3,486,000	3,814,000
Selling, general and administrative	3,384,000	3,251,000
Total operating expenses	6,870,000	7,065,000
Income from operations	624,000	2,001,000
Interest income	301,000	252,000
Other (expense) income, net	(99,000)	116,000
Income before provision for income taxes	826,000	2,369,000
Provision for income taxes	229,000	700,000
Net income	$ 597,000	$ 1,669,000
Net income per share
Basic	$ 0.05	$ 0.13
Diluted	$ 0.05	$ 0.13
Shares used in per share computation:
Basic	11,999	12,755
Diluted	12,001	12,777