3. Summary of Significant Accounting Policies (Details Narrative) - USD ($)	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016
Allowance for doubtful accounts	$ 14,000	$ 15,000
Allowance for sales discounts, rebates, distributor fees and returns	672,000	653,000
Inventory reserves	61,000	164,000
Transfers in or out of Level 3	0	0
Asset impairment charges	0	0
Research and development expenses	1,576,000	1,806,000
Advertising costs	149,000	175,000
Shipping and handling costs	49,000	59,000
Foreign currency translation adjustment	(324,000)	(347,000)
Foreign currency transaction gain (loss)	36,000	38,000
Accumulated other comprehensive loss	$ (4,178,000)	$ (3,854,000)
Accounts Receivable [Member] \| One Customer [Member]
Significant customer concentration	26.00%	33.00%
Accounts Receivable [Member] \| One Customer [Member]
Significant customer concentration	12.00%
Accounts Receivable [Member] \| One Customer [Member]
Significant customer concentration	10.00%
Revenues [Member] \| One Customer [Member]
Significant customer concentration	12.00%	40.00%
Revenues [Member] \| One Customer [Member]
Significant customer concentration		15.00%
Revenues [Member] \| One Customer [Member]
Significant customer concentration		14.00%
Revenues [Member] \| One Customer [Member]
Significant customer concentration	10.00%
Revenues [Member] \| One Customer [Member]
Significant customer concentration	10.00%
Revenues [Member] \| Two Customers [Member]
Significant customer concentration		12.00%

Allowance for sales discounts, rebates, distributor fees and returns

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of valuation reserve for inventory.

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Expenditures for planning and executing the conception, pricing, promotion, and distribution of ideas, goods, and services. Costs of public relations and corporate promotions are typically considered to be marketing costs.

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Amount before tax, after reclassification adjustments of gain (loss) on foreign currency translation adjustments, on foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature, attributable to parent entity.

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The aggregate costs incurred (1) in a planned search or critical investigation aimed at discovery of new knowledge with the hope that such knowledge will be useful in developing a new product or service, a new process or technique, or in bringing about a significant improvement to an existing product or process; or (2) to translate research findings or other knowledge into a plan or design for a new product or process or for a significant improvement to an existing product or process whether intended for sale or the entity's use, during the reporting period charged to research and development projects, including the costs of developing computer software up to the point in time of achieving technological feasibility, and costs allocated in accounting for a business combination to in-process projects deemed to have no alternative future use.

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Cost incurred during the reporting period in transporting goods and services to customers. Includes freight-out costs.

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