GEOGRAPHIC INFORMATION (Tables)

9 Months Ended

Feb. 28, 2023

Geographic Information Disclosure Abstract

Revenue from External Customers by Geographic Areas [Table Text Block]

	Three Months Ended February 28,				Nine Months Ended February 28,
	2023		2022		2023		2022
Revenues from sales to unaffiliated customers:
Asia	$	345,000	$	4,877,000	$	1,822,000	$	8,925,000
Europe		301,000		2,416,000		1,268,000		3,683,000
North America		461,000		286,000		1,130,000		820,000
South America		5,000		81,000		11,000		87,000
Middle East		-		-		-		54,000
	$	1,112,000	$	7,660,000	$	4,231,000	$	13,569,000