CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS (UNAUDITED) - USD ($)	3 Months Ended		9 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017
Income Statement [Abstract]
Revenues	$ 2,099,300	$ 1,910,900	$ 5,272,600	$ 6,153,800
Cost of revenues	1,331,500	1,054,800	3,287,300	3,833,200
Gross profit	767,800	856,100	1,985,300	2,320,600
Operating Expenses:
General and administrative	470,200	435,100	1,306,600	1,256,700
Selling	263,800	223,900	679,500	664,800
Research & development	117,700	114,100	379,700	334,500
Total operating expenses	851,700	773,100	2,365,800	2,256,000
Income (loss) from operations	(83,900)	83,000	(380,500)	64,600
Other income (expense):
Interest income	0	1,100	5,600	10,100
Other income, net	500	0	1,900	5,700
Interest expense	(500)	(1,200)	(1,100)	(2,200)
Total other income (expense), net	0	(100)	6,400	13,600
Income (loss) before income tax expense (benefit)	(83,900)	82,900	(374,100)	78,200
Income tax expense (benefit):
Current	9,700	38,900	17,800	23,400
Deferred	(55,900)	(21,600)	(40,400)	(7,400)
Total income tax expense (benefit)	(46,200)	17,300	(22,600)	16,000
Net income (loss)	$ (37,700)	$ 65,600	$ (351,500)	$ 62,200
Basic earnings (loss) per common share	$ (0.03)	$ 0.04	$ (0.24)	$ 0.04
Diluted earnings (loss) per common share	(0.03)	0.04	(0.24)	.04
Cash dividends declared per common share	$ .00	$ 0.03	$ .00	$ 0.03