Note 2 - Summary of Significant Accounting Policies (Details Textual)	3 Months Ended
Sep. 30, 2016 USD ($) shares	Sep. 30, 2015 USD ($) shares
Minimum [Member]
Media Content Service Period	30 days
Finite-Lived Intangible Asset, Useful Life	7 years
Standard Warranty Term	1 year
Maximum [Member] \| Leasehold Improvements [Member]
Property, Plant and Equipment, Useful Life	15 years
Maximum [Member] \| Product Warranty Exceptions [Member]
Standard Warranty Term	10 years
Maximum [Member]
Media Content Service Period	1 year
Finite-Lived Intangible Asset, Useful Life	20 years
Standard Warranty Term	5 years
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Asset	$ 0
Fair Value Disclosure, Off-balance Sheet Risks, Amount, Liability	$ 0
Number of Revenue Sources	5
Cash, FDIC Insured Amount	$ 250,000
Cash, Uninsured Amount	34,816,000	$ 37,883,000
Depreciation	1,728,000	1,450,000
Research and Development Expense	$ 1,401,000	$ 1,311,000
Incremental Common Shares Attributable to Dilutive Effect of Contingently Issuable Shares \| shares	914,000	693,000

The period of time for media content service.

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- Definition

Represents the number of sources (for example, categories of activities to provide goods and services) from which the Company earns revenue.

+ References

No definition available.

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- Definition

This item represents the amount of time covered by the Company's standard product warranty.

+ References

No definition available.

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- Definition

The amount of cash deposited in financial institutions as of the balance sheet date that is insured by the Federal Deposit Insurance Corporation.

+ References

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The amount of cash as of the balance sheet date that is not insured by the Federal Deposit Insurance Corporation.

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The fair value of financial assets, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of contingently issuable shares. Contingently issuable shares are those shares that are issuable for little or no cash contingent on certain conditions being met.

+ References

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

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.

+ References

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