Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Operating activities:
Net loss	$ (1,727)	$ (2,478)
Adjustments to reconcile net loss to cash used in operating activities:
Depreciation and amortization	742	875
Share-based compensation	188	242
Gain on disposal of equipment		(23)
Allowance for excess inventory quantities		52
Changes in assets and liabilities related to operations:
Trade accounts receivable	(336)	979
Other receivables	1	26
Inventories	26	111
Prepaid expenses and other assets	(167)	39
Accounts payable	5	(180)
Accrued expenses	87	(165)
Net cash used in operating activities	(1,181)	(522)
Investing activities:
Proceeds from disposal of equipment		23
Acquisition of equipment and leasehold improvements	(216)	(279)
Payment of accounts payable incurred for the purchase of equipment and leasehold improvements	(23)	(20)
Net cash used in investing activities	(239)	(276)
Financing activities:
Principal payment on capital leases	(34)	(57)
Proceeds from sale of investment	30
Proceeds from exercise of stock options	10	7
Net cash provided by (used in) financing activities	6	(50)
Decrease in cash and cash equivalents	(1,414)	(848)
Cash and cash equivalents at beginning of period	3,276	4,124
Cash and cash equivalents at end of period	1,862	3,276
Supplemental cash flow information:
Interest paid	6	12
Supplemental non-cash investing and financing activities:
Accounts payable incurred for the purchase of equipment and leasehold improvements	8	23
Capital lease obligations incurred in the purchase of equipment	$ 184