STOCK BASED COMPENSATION (Details - Compensation Expense) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated stock-based compensation	$ 859	$ 847	$ 1,585	$ 1,578
Research and Development Expense [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated stock-based compensation	295	267	539	490
General and Administrative Expense [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated stock-based compensation	499	554	928	1,009
Selling and Marketing [Member]
Share-Based Payment Arrangement, Expensed and Capitalized, Amount [Line Items]
Allocated stock-based compensation	$ 65	$ 26	$ 118	$ 79