Statements of Operations (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 26, 2015	Sep. 27, 2014	Sep. 26, 2015	Sep. 27, 2014
Income Statement [Abstract]
Product sales	$ 5,423,107	$ 5,984,623	$ 16,307,008	$ 17,066,725
Research and development under cooperative agreement		85,607	42,254	124,218
Total Revenues	$ 5,423,107	6,070,230	16,349,262	17,190,943
Cost of product sales	$ 4,448,991	4,658,194	12,905,775	13,150,046
Cost of research and development under cooperative agreement		72,861	34,970	105,017
Gross Margin	$ 974,116	1,339,175	3,408,517	3,935,880
Selling, general and administrative expense	960,321	1,017,811	3,085,454	3,296,813
Operating income	13,795	321,364	323,063	639,067
Interest income (expense), net	1,454	(299)	2,305	(1,800)
Net income before income tax expense	15,249	321,065	325,368	637,267
Income tax expense	7,000	127,000	129,500	253,000
Net income	$ 8,249	$ 194,065	$ 195,868	$ 384,267
Net income per basic common share	$ 0.00	$ 0.01	$ 0.01	$ 0.03
Weighted average number of basic common shares outstanding	13,197,827	13,091,819	13,174,598	13,082,135
Net income per diluted common share	$ 0.00	$ 0.01	$ 0.01	$ 0.03
Weighted average number of diluted common shares outstanding	13,611,956	13,737,953	13,656,888	13,716,378