Consolidated Statements of Stockholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Jan. 02, 2022	11,863
Balance at Jan. 02, 2022	$ 12	$ 310,222	$ (301,025)	$ 9,209
Common stock issued under stock plans and employee stock purchase plans (in shares)	542
Common stock issued under stock plans and employee stock purchase plans	$ 0	253	0	253
Common stock offering, net of issuance costs (in shares)	797
Common stock offering, net of issuance costs	$ 1	4,664	0	4,665
Stock-based compensation	0	2,035	0	2,035
Net loss	$ 0	0	(4,267)	(4,267)
Balance (in shares) at Jan. 01, 2023	13,202
Balance at Jan. 01, 2023	$ 13	317,174	(305,292)	11,895
Common stock issued under stock plans and employee stock purchase plans (in shares)	466
Common stock issued under stock plans and employee stock purchase plans		199	0	200
Common stock offering, net of issuance costs (in shares)	450
Common stock offering, net of issuance costs	$ 0	2,293	0	2,293
Stock-based compensation	0	2,770	0	2,770
Net loss	0	0	(263)	(263)
Common stock issued under stock plans and employee stock purchase plans	$ 1
Balance (in shares) at Dec. 31, 2023	14,118
Balance at Dec. 31, 2023	$ 14	322,436	(305,555)	16,895
Common stock issued under stock plans and employee stock purchase plans (in shares)	572
Common stock issued under stock plans and employee stock purchase plans	$ 0	310	0	310
Common stock offering, net of issuance costs (in shares)	646
Common stock offering, net of issuance costs	$ 1	6,758	0	6,759
Stock-based compensation	0	4,764	0	4,764
Net loss	$ 0	0	(3,841)	(3,841)
Balance (in shares) at Dec. 29, 2024	15,336
Balance at Dec. 29, 2024	$ 15	$ 334,268	$ (309,396)	$ 24,887