Note 2 - Significant Accounting Policies (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Jan. 31, 2021	Jan. 31, 2020
Foreign Currency Transaction Gain (Loss), Realized	$ 100	$ 400
Cash and Cash Equivalents, at Carrying Value, Ending Balance	7,174	13,371
Broker-Dealer, Draft Payable	100	100
Restricted Cash and Cash Equivalents, Total	1,201	1,287
Receivables, Long-term Contracts or Programs, Total	2,700	2,600
Depreciation, Total	4,700	4,400
Impairment of Long-Lived Assets Held-for-use	0	0
Goodwill, Impairment Loss	0	0
Finite-Lived Patents, Gross	2,600	2,700
Finite-Lived Intangible Assets, Accumulated Amortization	2,500	2,500
Amortization of Intangible Assets, Total	100
Finite-Lived Intangible Asset, Expected Amortization, Year One	100
Finite-Lived Intangible Assets, Amortization Expense, after Year Five	$ 100
Finite-Lived Intangible Asset, Useful Life (Year)	2 years 292 days
Research and Development Expense, Total	$ 300	300
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
Accounts Receivable [Member]
Accounts Receivable, before Allowance for Credit Loss	3,800	$ 4,100
Receivables, Long-term Contracts or Programs, Total	3,400
Proceeds from Sale and Collection of Receivables, Total	200
Accounts Receivable, Allowance for Credit Loss, Ending Balance	0
Accounts Receivable [Member] | Customer Concentration Risk [Member]
Concentration Risk, Percentage		13.30%
Accounts Receivable [Member] | Other Noncurrent Assets [Member]
Receivables, Long-term Contracts or Programs, Total	2,400	$ 2,100
Revenue Benchmark [Member] | Customer Concentration Risk [Member]
Concentration Risk, Percentage		11.50%
Geographic Distribution, Domestic [Member]
Cash and Cash Equivalents, at Carrying Value, Ending Balance	100	$ 300
Restricted Cash and Cash Equivalents, Total	0	0
Geographic Distribution, Foreign [Member]
Cash and Cash Equivalents, at Carrying Value, Ending Balance	7,100	13,100
Restricted Cash and Cash Equivalents, Total	$ 1,200	$ 1,300