Note 3 - Inventories (Details) - Inventories (USD $) In Thousands, unless otherwise specified	Jun. 29, 2013	Mar. 30, 2013
Inventories [Abstract]
Raw materials	$ 2,148	$ 2,157
Work-in-progress	1,902	2,049
Finished goods	124	50
Demonstration inventory	319	304
Total	$ 4,493	$ 4,560

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Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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Gross amount of merchandise, goods, commodities, or supplies to which the entity holds the title and uses for the specific purpose of showing the benefits and features of the entity's products to existing or potential customers.

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