Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($)	Sep. 30, 2018	Jun. 30, 2018
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 200,000	$ 200,000
Accumulated amortization and depreciation	9,355,964	9,023,235
Patents, net of accumulated amortization	$ 1,097,252	$ 1,063,393
Common stock, authorized	40,000,000	40,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, issued	9,481,251	9,430,466
Common stock, outstanding	9,481,251	9,430,466