Nature of Business and Summary of Significant Accounting Policies - Income Statement location (Details) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022	Dec. 31, 2021
Research and development	$ 2,222,000	$ 1,978,000	$ 4,650,000	$ 3,909,000
Net sales	42,314,000	33,408,000	81,807,000	64,459,000
Cost of sales	27,960,000	21,965,000	52,887,000	39,560,000
Selling, General and Administrative Expenses
Advertising and promotion costs	505,000	512,000	1,259,000	1,598,000
Operating Expenses.
Research and development	2,222,000	1,978,000	4,650,000	3,909,000
Cost of sales | Shipping and Handling
Cost of sales	454,000	361,000	848,000	694,000
Sales revenue, net | Shipping and Handling
Net sales	$ 128,000	$ 106,000	$ 240,000	$ 212,000