Segment Information (Tables)

6 Months Ended

Jun. 30, 2020

Segment Reporting [Abstract]

Schedule of geographic region

	Three months ended June 30,				Six months ended June 30,
	2020		2019		2020		2019
	(in thousands)				(in thousands)
North America	$	1,135	$	697	$	2,175	$	1,560
Asia		155		72		268		119
Other		—		—		7		10
Total revenue	$	1,290	$	769	$	2,450	$	1,689

	Three months ended June 30,				Six months ended June 30,
	2020		2019		2020		2019
	(in thousands)				(in thousands)
Optical	$	1,090	$	738	$	2,117	$	1,658
Direct Dose Rx		200		31		333		31
Total revenue	$	1,290	$	769	$	2,450	$	1,689

	As of June 30,		As of December 31,
	2020		2019
	(in thousands)
North America	$	25,038	$	29,703
Asia		6,843		5,094
Other		—		4
Total assets	$	31,881	$	34,801