CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($)	3 Months Ended		6 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017
Income Statement [Abstract]
Revenues	$ 2,163,200	$ 1,892,400	$ 4,201,800	$ 3,173,300
Cost of revenues	1,187,500	1,126,700	2,280,400	1,955,900
Gross profit	975,700	765,700	1,921,400	1,217,400
Operating Expenses:
General and administrative	462,100	407,900	878,600	836,300
Selling	248,200	214,600	484,300	415,600
Research & development	109,400	132,900	226,700	262,000
Total operating expenses	819,700	755,400	1,589,600	1,513,900
Income (loss) from operations	156,000	10,300	331,800	(296,500)
Other income (expense):
Interest income	2,500	5,200	2,800	5,600
Other income, net	(9,300)	1,400	(7,400)	1,400
Interest expense	(400)	(500)	(800)	(600)
Total other income (expense), net	(7,200)	6,100	(5,400)	6,400
Income (loss) before income tax expense	148,800	16,400	326,400	(290,100)
Income tax expense (benefit):
Current	24,400	71,800	53,900	8,000
Deferred	6,000	25,600	12,000	15,500
Total income tax expense	30,400	97,400	65,900	23,500
Net income (loss)	$ 118,400	$ (81,000)	$ 260,500	$ (313,600)
Basic earnings (loss) per common share	$ 0.08	$ (.05)	$ 0.17	$ (.21)
Diluted earnings (loss) per common share	0.08	(0.05)	0.17	(.21)
Cash dividends declared per common share	$ 0.05	$ 0.00	$ 0.05	$ 0.00