Note 2 - Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2022	Jan. 31, 2021
Foreign Currency Transaction Gain (Loss), Realized	$ 100	$ 100
Cash and Cash Equivalents, at Carrying Value, Ending Balance	8,214	7,174
Broker-Dealer, Draft Payable	200	100
Restricted Cash and Cash Equivalents, Total	1,557	1,201
Receivables, Long-term Contracts or Programs, Total	4,300	2,700
Depreciation, Total	4,100	4,300
Impairment, Long-Lived Asset, Held-for-Use, Total	0
Goodwill, Impairment Loss	0
Finite-Lived Patents, Gross	2,700	2,600
Finite-Lived Intangible Assets, Accumulated Amortization	2,600	2,500
Finite-Lived Intangible Asset, Expected Amortization, Year One	100
Finite-Lived Intangible Asset, Expected Amortization, Year Two	100
Finite-Lived Intangible Asset, Expected Amortization, Year Three	100
Finite-Lived Intangible Asset, Expected Amortization, Year Four	100
Finite-Lived Intangible Asset, Expected Amortization, Year Five	100
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	$ 100
Finite-Lived Intangible Asset, Useful Life (Year)	3 years 4 months 24 days
Research and Development Expense, Total	$ 400	300
Minimum [Member]
Property, Plant and Equipment, Useful Life (Year)	3 years
Maximum [Member]
Property, Plant and Equipment, Useful Life (Year)	30 years
Accounts Receivable [Member]
Accounts Receivable, before Allowance for Credit Loss	$ 3,600	3,800
Receivables, Long-term Contracts or Programs, Total	3,400	3,400
Proceeds from Sale and Collection of Receivables, Total	100
Accounts Receivable, Allowance for Credit Loss, Ending Balance	$ 0
Accounts Receivable [Member] | Customer Concentration Risk [Member] | One Customer [Member]
Concentration Risk, Percentage	11.90%
Accounts Receivable [Member] | Other Noncurrent Assets [Member]
Receivables, Long-term Contracts or Programs, Total	$ 2,000	2,400
Geographic Distribution, Domestic [Member]
Cash and Cash Equivalents, at Carrying Value, Ending Balance	100	100
Restricted Cash and Cash Equivalents, Total	0	0
Geographic Distribution, Foreign [Member]
Cash and Cash Equivalents, at Carrying Value, Ending Balance	8,200	7,100
Restricted Cash and Cash Equivalents, Total	$ 1,600	$ 1,200