Nature of Business and Summary of Significant Accounting Policies - Income Statement location (Details) - USD ($)	3 Months Ended		9 Months Ended
	Mar. 31, 2023	Mar. 31, 2022	Mar. 31, 2023	Mar. 31, 2022
Research and development	$ 2,314,000	$ 2,009,000	$ 6,964,000	$ 5,918,000
Net sales	43,532,000	35,905,000	125,339,000	100,364,000
Cost of sales	22,253,000	20,872,000	75,140,000	60,432,000
Selling, General and Administrative Expenses
Advertising and promotion costs	926,000	655,000	2,185,000	2,253,000
Operating Expenses.
Research and development	2,314,000	2,009,000	6,964,000	5,918,000
Cost of sales | Shipping and Handling
Cost of sales	437,000	339,000	1,285,000	1,033,000
Sales revenue, net | Shipping and Handling
Net sales	$ 106,000	$ 106,000	$ 346,000	$ 318,000