Nature of Business and Summary of Significant Accounting Policies - Additional information (Details)		3 Months Ended		9 Months Ended
	Jul. 01, 2019 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)	Mar. 31, 2021 USD ($) segment	Mar. 31, 2020 USD ($)	Jun. 30, 2020 USD ($)
Research and development		$ 1,902,000	$ 1,815,000	$ 5,675,000	$ 5,387,000
Valuation allowances and reserves, balance		196,000		$ 196,000		$ 326,000
Number of share incentive programs				four
Stock based compensation expense		84,000	172,000	$ 272,000	497,000
Foreign currency realized/unrealized gains(loss)		0	0	$ 0	0
Operating segments | segment				1
Cost of sales		15,318,000	14,283,000	$ 43,601,000	42,752,000
Operating lease liability	$ 7,700,000
Operating lease asset	$ 7,700,000	7,379,000		7,379,000		$ 7,395,000
Lease, Practical Expedients, Package [true false]	true
Selling, General and Administrative
Advertising and promotion costs		229,000	307,000	919,000	1,448,000
Cost of sales
Research and development		1,902,000	1,815,000	5,675,000	5,387,000
Shipping and Handling | Cost of sales
Cost of sales		91,000	135,000	290,000	355,000
Shipping and Handling | Sales revenue, net
Cost of sales		$ 281,000	$ 300,000	$ 732,000	$ 831,000