Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)
Cash and Cash Equivalent	$ 26,338	$ 6,895
Credit Terms for Trade Receivables (Day)		30 days
Extended Credit Terms for Trade Receivables (Day)		60 days
Short-Term Investments	0	$ 30,227
Impairment of Intangible Assets, Finite-Lived	$ 0	2,761
Emerging Markets [Member]
Impairment of Intangible Assets, Finite-Lived		$ 2,800
Accounts Receivable [Member] \| Customer Concentration Risk [Member]
Number of Major Customers	2	2
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Concentration Risk, Percentage	19.10%
Accounts and Financing Receivable, after Allowance for Credit Loss	$ 7,300
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Concentration Risk, Percentage		16.20%
Accounts and Financing Receivable, after Allowance for Credit Loss		$ 2,200
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Concentration Risk, Percentage		27.40%
Accounts and Financing Receivable, after Allowance for Credit Loss		$ 4,100
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Concentration Risk, Percentage		16.00%
Accounts and Financing Receivable, after Allowance for Credit Loss		$ 9,500
Revenue Benchmark [Member] \| Product Concentration Risk [Member] \| Thermal Film [Member]
Concentration Risk, Percentage	7.00%	5.00%
Non-US [Member]
Cash and Cash Equivalent	$ 800
Subsidiaries [Member] \| Non-US [Member]
Cash and Cash Equivalent	$ 800

Credit terms for trade receivables.

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Extended credit terms for trade receivables.

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Represents the number of major customers accounting for 10% or more of the specified concentration risk benchmark, which includes, but not limited to, sales revenue, accounts receivable, etc.

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Amount, after allowance for credit loss, of accounts and financing receivable. Includes, but is not limited to, notes and loan receivable.

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Amount of cash and cash equivalent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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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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The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of a finite-lived intangible asset to fair value.

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Amount of investments including trading securities, available-for-sale securities, held-to-maturity securities, and short-term investments classified as other and current.

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