Condensed Statements of Operations - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Revenue:
Product	$ 407,177	$ 577,127	$ 948,321	$ 1,177,317
Service	1,353,579	1,318,689	2,183,604	1,583,731
Total revenue	1,760,756	1,895,816	3,131,925	2,761,048
Cost of revenue	1,236,904	932,976	2,532,206	1,776,446
Gross margin	523,852	962,840	599,719	984,602
Operating expenses:
Selling, general and administrative	4,413,437	4,712,637	8,651,904	9,406,345
Research and development	1,618,889	2,611,591	2,885,952	4,605,692
Total operating expenses	6,032,326	7,324,228	11,537,856	14,012,037
Operating loss	(5,508,474)	(6,361,388)	(10,938,137)	(13,027,435)
Other income (expense):
Interest expense	(350,058)	(538,889)	(748,478)	(931,346)
Interest income	17,622	31,092	29,711	66,571
Total other income (expense)	(332,428)	(489,355)	(718,759)	(846,333)
Other income	8	18,442	8	18,442
Net loss before income taxes	(5,840,902)	(6,850,743)	(11,656,896)	(13,873,768)
Provision for income taxes		860	280	4,259
Net loss	$ (5,840,902)	$ (6,851,603)	$ (11,657,176)	$ (13,878,027)
Net loss per share, basic and diluted	$ (0.60)	$ (0.98)	$ (1.31)	$ (2.00)
Shares used in computing net loss per share, basic and diluted	9,769,322	7,018,502	8,875,177	6,952,012